Haploinsufficiency of A20 caused by heterozygous mutations in the TNFAIP3 gene:A Case Series

Haploinsufficiency of A20 caused by heterozygous mutations in the TNFAIP3 gene:A Case Series | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Haploinsufficiency of A20 caused by heterozygous mutations in the TNFAIP3 gene:A Case Series Hengpan Yao, Yijing Liu, MengJun Dong, Kairui Yang, Zhidan Yv, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6493389/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 3 You are reading this latest preprint version Abstract Objectives Children with A20 haploinsufficiency, resulting from heterozygous mutations in the TNFAIP3 gene, are increasingly being identified. However, their diagnosis and treatment remain challenging and are not yet fully optimized. The clinical, genetic characteristics and treatment methods of five children with HA20 from different families were collected from Henan Children's Hospital between April 2019 and August 2023 to evaluated for accumulating experience in the management of this rare condition. Results We identified five heterozygous mutations inthe TNFAIP3 gene among the five children, including c.866delA: p.H289Pfs* 3, c.1243_1247delAAAAC: p.N416Tfs* 11, chr6: 136693638_138817508del, c.133C>T: p.R45X, c.1903_1906delAAAC: p.K635fs* 61. The mutations in Patients 1, 2, 4, and 5 were de novo, while the three mutations in Patient 3 were inherited from the mother. Mutations in patients 3 and 5 have not been reported. All five patients presented with childhood-onset recurrent fever and intermittent diarrhea, which are hallmark features of HA20. Additionally, two of the five patients experienced intermittent bloody stool, three had oral ulcers, and two presented with skin symptoms, further aligning with the clinical manifestations of HA20. Laboratory tests revealed elevated inflammatory markers, including increased white blood cell (WBC) counts, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). Endoscopic observation, there were ulcers in different parts of the intestine. Each child was treated with the oral drug thalidomide, 4 children (80%) received glucocorticoids to reduce inflammation, and had different biological agents according to individual differences. During follow-up, we observed significant improvement in all children who received targeted treatment. Conclusions HA20 is a rare monogenic early-onset auto-inflammatory disease. It can present with a variety of clinical manifestations, including Behçet-like syndrome, inflammatory bowel disease, lupus-like syndrome and periodic fever syndrome. Whole-exome sequencing should be actively considered for children who present with early-onset symptoms or features suggestive of autoimmune diseases. A20 haploinsufficiency TNFAIP3 autoinflammatory diseases heterozygous mutations Figures Figure 1 Figure 2 Figure 3 Introduction HA20 (Haploinsufficiency of A20) was first reported in 2016 by Zhou et al [ 1 ] . To date, over 100 cases have been documented, predominantly among Japanese populations, with relatively fewer reports from China. HA20 is an autosomal dominant hereditary disorder caused by pathogenic mutations in the tumor necrosis factor (TNF)-α-induced protein 3 gene ( TNFAIP3 ) [ 2 – 4 ] . The A20 protein, encoded by TNFAIP3 , contains two functional domains: the N-terminal OTU domain and the C-terminal ZnF (zinc finger) domain, both of which play critical roles in regulating the nuclear factor κB (NF-κB) signaling pathway. Specifically, A20 facilitates the degradation of activated NF-κB through ubiquitination, thereby inhibiting inflammatory responses. In HA20 patients, mutations in TNFAIP3 typically result in loss-of-function of the A20 protein, leading to dysregulation of the NF-κB pathway and subsequent recurrent autoinflammatory responses. These mutations often manifest as nonsense mutations, causing premature termination of A20 protein translation and production of a truncated, non-functional protein. Clinical manifestations of HA20 are diverse and include recurrent fever, diarrhea, oral and genital ulcers, uveitis, and vasculitis [ 5 – 11 ] . When these symptoms appear, especially in pediatric patients, HA20 should be considered as a differential diagnosis. Early-stage HA20 often presents with recurrent mucosal ulcers, necessitating differentiation from conditions such as rheumatoid arthritis, juvenile idiopathic arthritis, periodic fever with aphthous stomatitis, pharyngitis, and adenitis (PFAPA), hyperimmunoglobulinemia D syndrome (HIDS), and inflammatory bowel disease. Whole-exome sequencing (WES) aids clinicians in identifying TNFAIP3 mutations, thus confirming the diagnosis of HA20. Several studies highlight that clinical presentations of HA20 can vary even among patients with identical mutations or within the same family. Moreover, patients with the same pathogenic variant may respond differently to the same treatment regimen, suggesting that other genetic or environmental factors may influence HA20 pathogenesis. Currently, there is no standardized treatment approach for HA20. While most children respond well to glucocorticoids, long-term use is associated with significant side effects. Colchicine therapy has shown efficacy in mild to moderate cases. Treatment selection appears to depend on the patient's primary clinical phenotype. Responses to immunosuppressive agents (methotrexate, cyclosporine, hydroxychloroquine, thalidomide, tacrolimus, and malacenthol) have been variable. For refractory cases, biologics (TNF-α inhibitors, anti-IL-1 drugs, anti-IL-6 drugs, and JAK inhibitors) offer potential new treatment options [ 12 , 13 ] . A minority of patients have achieved remission through hematopoietic stem cell transplantation (HSCT), including both autologous and allogeneic transplants. Given the limited number of HA20 studies, clear diagnostic criteria have yet to be established. Gene sequencing combined with clinical manifestations can assist in diagnosis. This study analyzed the clinical and genetic data of five unrelated Chinese families to enhance understanding of HA20 diagnosis and treatment. Methods A retrospective analysis was conducted on five children diagnosed with HA20 at Henan Children's Hospital between April 2019 and August 2023. Informed consent was obtained from all legal guardians to review the electronic medical records of the diagnosed children. Genetic testing data from whole-exome sequencing (WES), along with demographic, clinical, and laboratory data, were collected for each child. Imaging results, including ultrasound and magnetic resonance imaging, and gastrointestinal findings were also reviewed for some patients. The course of illness, symptom exacerbation and relief, targeted drug usage (corticosteroids, infliximab, adalimumab, etc. ), symptom changes, and treatment outcomes post-discharge were recorded. Case series Demographic and Clinical Characteristics Five children with HA20 were confirmed in the Gastroenterology Department of Henan Children's Hospital between April 2019 and August 2023. Table 1 summarizes their baseline demographics and clinical characteristics and treatment follow-up. All patients aged from 2 to 10 years and experienced childhood-onset symptoms, with two female and three male patients. None of the patients reported a family history of genetic disorders or any special allergies. All five children with HA20 exhibited common symptoms of recurrent fever and gastrointestinal symptoms, including abdominal pain, diarrhoea and gastrointestinal ulcers at the onset of the disease. Oral ulcers were observed in three patients (60%), skin lesions on the extremities and trunk in two patients (40%), genital ulcers in one patient (20%) and arthritis in one patient (20%). In routine blood tests, inflammatory markers (CRP, ESR) were elevated in all five children. Notably, CRP levels were particularly high in cases 2, 3 and 4, while significant hematological sedimentation was observed in cases 1, 3 and 5 (Table 2 ) . Characteristics of mutant genes Genomic testing revealed heterozygous mutations in the TNFAIP3 gene among the five patients (Fig. 1). Specifically, Patient 4 exhibited a nonsense mutation characterized by a base substitution of c.133C > T, resulting in an amino acid sequence alteration of p.R45X. Patient 3 presented with a large segmental deletion, detailed as chr6: 136693638_138817508del. Patients 1, patient 2 and patient 5 showed frameshift mutations including c.866delA: p.H289Pfs* 3, c.1243_1247delAAAAC: p.N416Tfs* 11, c.1903_1906delAAAC: p.K635fs* 61. Further analysis indicated that the mutations in Patients 1, 2, 4, and 5 were de novo, while the three mutations in Patient 3 were inherited from the mother. Mutations in patients 3 and 5 have not been reported. Endoscopic characteristics Gastrointestinal ulcers are a common issue in children with HA20, varying in location and severity (Fig. 2). Specifically, patients 1, 2, and 3 exhibited multiple ulcers in the colon and rectum. Patient 4 had ulcers in the transverse colon, descending colon, sigmoid colon, and rectum. Patient 5 presented with ulcers in the ileocecum, ascending colon, transverse colon, and descending colon. Treatment and follow-up Patient 1 developed severe hormone-dependent allergic reactions during treatment with glucocorticoids, thalidomide, and infliximab. Symptoms improved after switching to adalimumab. Patients 2, 3, and 5 were treated with corticosteroids and thalidomide. Patient 4 underwent surgical repair for jejunal perforation and was subsequently treated with oral thalidomide. Additionally, patient 2 was diagnosed with HA20 and methylmalonic aciduria (MMA) and received hydroxocobalamin (1 mg daily). After one week, urine organic acid screening and blood homocysteine levels normalized, and hydroxocobalamin dosage was tapered to 1.5 mg weekly. Patients 4, 2, and 3 were followed up for 3 years and 4 months, 3 years, and 1 year, respectively, with complete resolution of symptoms. Patient 1 was followed for 2 years and 3 months, showing improvement in digestive tract symptoms but persistent cecal ulcers. Patient 5 experienced improvement in gastrointestinal symptoms after one month. Discussion We conducted a systematic literature review of articles reporting TNFAIP3 mutations from 2016 to January 2024 [ 14 ] . We conducted a systematic literature review of articles reporting TNFAIP3 mutations from 2016 to January 2024. A total of 168 patients from 85 families with genetically confirmed HA20 were included, excluding those with additional gene mutations or incomplete data. The cohort comprised 61 males and 101 females, with the earliest onset at five days and the longest disease duration exceeding 60 years. Mutation sites in the TNFAIP3 gene varied widely (Fig. 3) [ 15 , 16 ] . The TNFAIP3 gene encodes the A20 protein, which plays a crucial role in regulating NF-κB signaling. Aberrant activation of NF-κB signaling is closely associated with multiple autoimmune diseases [ 17 – 19 ] . Therefore, these mutations may impair A20 protein function, affecting NF-κB regulation and increasing the risk of autoimmune diseases [ 20 – 22 ] . Notably, despite all patients having heterozygous TNFAIP3 mutations, clinical manifestations varied, likely due to differences in mutation type, location, and genetic background. For instance, segmental deletions in patient 3 may affect a broader region of the gene with more complex physiological effects, while spontaneous mutations in patients 1, 2, 4, and 5 may result in varying degrees of impaired A20 function. Future studies will explore how these mutations influence clinical presentation and treatment response, aiding in understanding disease pathogenesis and improving treatment options. Clinical phenotypic differences in HA20 are not solely determined by genetic mutation sites. A20 is a highly conserved protein with two domains: the amino-terminal OTU domain and seven carboxyl-terminal ZnF domains [ 23 – 25 ] . Patients with impaired OTU or ZnF domains alone do not develop ocular dysfunction, atrophic gastritis, or dental abnormalities. Specifically, OTU domain mutations do not cause musculoskeletal disease, autoimmune thyroid disease, liver injury, recurrent respiratory infections, or interstitial lung disease, while ZnF domain mutations do not lead to kidney injury or other symptom variations. Thus, clinical phenotype variation may be influenced by modifier genes and/or environmental factors. Mutations in ZnF domains correlate with earlier HA20 onset compared to OTU domain mutations. Studies show that patients in the OTU group (median onset age: 10 years, IQR: 8–14) have later onset than those in the ZnF group (median onset age: 2.5 years, IQR: 0.6–5). In our study, three TNFAIP3 variants affected the ZnF domain (patients 2, 3, 5), with onset ages of 6 months, 1 year 7 months, and 1 year 6 months, consistent with Chen's study. Two variants affected the OTU domain (patients 1, 4), with onset ages of five years and shortly after birth. The small sample size in this study led to discrepancies with the median onset age of the OTU group in Chen's study. Chen also observed diverse clinical manifestations in HA20 patients evaluated for his study [ 26 ] . Specifically, the most common symptom was oral ulcers (70%), followed by recurrent fever (42%), gastrointestinal ulcers (40%), skin lesions (38%), genital ulcers (36%), and musculoskeletal disorders (34%). In contrast, in this report, recurrent fever was the most frequent symptom (100%), followed by gastrointestinal ulcers (80%), oral ulcers (60%), skin lesions (40%), musculoskeletal disorders (20%), and genital ulcers (20%). These discrepancies from previous literature may be attributed to the small sample size. HA20 must also be differentiated from other diseases such as Behçet's disease (BS) [ 27 – 29 ] . Many clinical features of HA20 are similar to BS, including oral ulcers, genital ulcers, gastrointestinal ulcers, and skin lesions [ 28 , 30 ] , leading to initial misdiagnosis. For instance, patient 1 and patient 4 exhibited gastrointestinal ulcers; patient 2 had rash, gastrointestinal ulcers, and oral ulcers; patient 3 presented with rash, gastrointestinal ulcers, and perianal ulcers, all of which can be easily confused with BS. The median age at onset for HA20 patients was 5.92 years (IQR: 1–10), typically occurring in early childhood, whereas BS usually manifests in early adulthood. Recurrent fever, severe intestinal inflammation, elevated acute phase reactants, and fluctuations in autoantibodies are less common in BS patients [ 31 ] . Infantile-onset inflammatory bowel disease (IBD) with perianal lesions is a form of monogenic IBD, and some HA20 cases exhibit varying degrees of perianal lesions, including severe perianal fistula. A rare disease study identified a 187 kb de novo microdeletion in the TNFAIP3 gene in an infant with infantile-onset IBD and perianal lesions, leading to a diagnosis of HA20 [ 32 ] . Therefore, HA20 should be differentiated from infantile-onset IBD with perianal lesions, and CNV analysis should be considered alongside whole exome sequencing (WES) to assess TNFAIP3 loss [ 33 ] . This approach provides more comprehensive genetic information for accurate diagnosis and treatment. Familial Mediterranean fever (FMF), caused by biallelic mutations in exon 10 of the MEFV gene, is characterized by recurrent fever, abdominal pain, and joint inflammation. Although HA20 and FMF share clinical similarities and both develop in early childhood, they are distinct autoinflammatory diseases. Treatment strategies also overlap, with most FMF patients responding well to colchicine, while a minority require IL-1 blockers. Given that HA20 patients exhibit excessive production of pro-inflammatory cytokines [ 34 – 36 ] , biologics targeting cytokines effectively inhibit systemic inflammatory responses, These include anti-TNF-α agents (infliximab, adalimumab), anti-IL-1 agents (anakinra, canakinumab), and anti-IL-6 agents (tocilizumab). Corticosteroids are routinely used for symptomatic control, and some patients respond to colchicine therapy, either alone or in combination with glucocorticoids or mesalazine [ 37 ] . Other immunotherapies, such as anti-CD20 monoclonal antibodies (rituximab), JAK-1 and − 3 inhibitors (tofacitinib), and thalidomide, have also been widely used [ 38 – 40 ] . Hematopoietic stem cell transplantation can be considered for severe refractory cases. Patient 2 had methylmalonic acidemia (MMA) from infancy. Early genetic testing, diagnosis, and treatment are crucial for managing such complex diseases. Patients with both HA20 and MMA provide valuable clinical insights into HA20, although this case is not representative of the general pediatric population. HA20 exhibits highly variable clinical manifestations, making clinical diagnosis challenging. Gene sequencing is essential for definitive diagnosis. This study has improved our understanding and diagnostic and therapeutic approaches. Accumulating more patient data will help establish phenotypes associated with the A20 genotype and provide a basis for clinical management. Abbreviations ACMG, American College of Medical Genetics and Genomics; ANA, antinuclear antibody; BS, Beasccet's disease; CRP, C-reactive protein; CMV, cytomegalovirus; CD, Cluster of Differentiation; CoA, coenzyme; CNKI, China National Knowledge Infrastructure; DUB, deubiquitinase; EBV, Epstein-Barr virus; ESR, erythrocyte sedimentation rate; HA20, haploinsufficiency of A20; Ig, Immunoglobulin; IL, interleukin; IQR, interquartile range; JAK, Janus kinase; MMA, Methylmalonic Acidaemia; NEMO, nuclear factor-κ-gene binding essential modulator; (NF)-κB, nuclear factor-κ-gene binding; OUT, ovarian tumour; TNFAIP3, tumor necrosis factor alpha induced protein 3; WES, Whole exome sequencing;WBC, white blood cell; ZnF, zinc finger; Declarations Ethics approval and consent to participate Ethical approval was waived by the local Ethics Committee of University Zhengzhou in view of the retrospective nature of the study and all the procedures being performed were part of the routine care. Consent for publication Patients signed informed consent regarding publishing their data and photographs. Availability of data and materials The dataset(s) supporting the conclusions of this article is(are) included within the article (and its additional file(s)). Competing interests The authors have no relevant financial or non-financial interests to disclose. Funding This work was supported by Key Medical Science and Technology Project of Henan Province (NO.SBGJ202002125) and Henan Provincial Science and Technology Plan Project (NO.232102311124). Authors' contributions All authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by Yijing Liu , MengJun Dong and Kairui Yang . The first draft of the manuscript was written by Hengpan Yao and all authors commented on previous versions of the manuscript. Fang Zhou and Zhidan Yv edited the manuscript . All authors read and approved the final manuscript . Acknowledgements First of all, l would like to give my heartfelt thanks to all thepeople who have ever helped me in this paper. My sincere and hearty thanks and appreciations go frstly to my supervisor, Ms. Fang Zhou, whose suggestions and encouragement have given me much insight into these translation studies. lt has been a great privilege and joy to study under his guidance and supervision. l am also extremely grateful to all my friends who have kindly provided me assistance and companionship in thecourse of preparing this paper. In addition, many thanks go to my family for their unfailing loveand unwavering support. Finally, l am really grateful to all those who devote much time toreading this thesis and give me much advice, Which will benefit mein my later study. References Zhou Q, Wang H, Schwartz DM, et al. Loss-of-function mutations in TNFAIP3 leading to A20 haploinsufficiency cause an early-onset autoinflammatory disease. Nat Genet. 2016. 48(1): 67-73. 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Characteristics of patients with TNFAIP3 mutations Characteristics Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 Genotype c.866delA: p.H289Pfs* 3 c.1243_1247delAAAAC: p.N416Tfs* 11 chr6: 136693638_138817508del c.133C>T: p.R45X c.1903_1906delAAAC: p.K635fs* 61 Sex F M M F M Age at genetic diagnosis (years) 5y8m 6m 2y7m 10m 1y6m Recurrent fever YES YES YES YES YES Oral ulcers YES NO YES NO YES Genital ulcers NO NO YES NO NO Skin lesions NO YES YES NO NO Gastrointestinal lesions YES YES YES YES YES Arthritis NO NO YES NO NO Treatment Thalidomide, glucocorticoid, infliximab, adalimumab Thalidomide, glucocorticoid Thalidomide, glucocorticoid Thalidomide Thalidomide, glucocorticoid Follow-up 2y3m; There is an ulcer in the ileocecal region 3y; Symptoms and endoscopic findings were completely relieved 1y; Symptoms and endoscopic findings were completely relieved 3y4m; Symptoms and endoscopic findings were completely relieved 1m; Symptoms were completely relieved a F: Female; b M: Male; c y: year; d m: month; Table 2. Laboratory findings of HA20 patients Laboratory findings Patient 1 Patient 2 Patient 3 Patient 4 Patient 5 WBC (5~12 × 109 /L) 13.45 20.2 18.45 13.41 10.98 Hemoglobin (11~16 g/dl) 90 110 91 94.2 103 Platelets (100~300 × 109 /L) 303 221 378 454 304 CRP (0~10.0 mg/L) 15.5 43.91 99.19 108.54 12.25 ESR (0~15 mm/h) 68 27 46 19 86 IL-6 (0-7pg/mL) 35.99 39.6 / / 19.76 Autoantibodies Negative ANA(1∶100) Negative / / Cite Share Download PDF Status: Under Review Version 1 posted Reviewers invited by journal 31 Jul, 2025 Editor assigned by journal 01 May, 2025 First submitted to journal 24 Apr, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6493389","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":493620718,"identity":"484c50c5-9aef-41c4-b998-bba57928b385","order_by":0,"name":"Hengpan Yao","email":"","orcid":"","institution":"Children's Hospital Affiliated of Zhengzhou University: Zhengzhou Children's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Hengpan","middleName":"","lastName":"Yao","suffix":""},{"id":493620719,"identity":"b750e72e-77d1-4b43-a96b-374de25ae27a","order_by":1,"name":"Yijing Liu","email":"","orcid":"","institution":"Children's Hospital Affiliated of Zhengzhou University: Zhengzhou Children's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Yijing","middleName":"","lastName":"Liu","suffix":""},{"id":493620720,"identity":"24d4e94e-73da-4ca4-bbe6-fc9cd726ffd4","order_by":2,"name":"MengJun Dong","email":"","orcid":"","institution":"Children's Hospital Affiliated of Zhengzhou University: Zhengzhou Children's Hospital","correspondingAuthor":false,"prefix":"","firstName":"MengJun","middleName":"","lastName":"Dong","suffix":""},{"id":493620721,"identity":"de600c88-75a3-4514-945e-926501bd8bd2","order_by":3,"name":"Kairui Yang","email":"","orcid":"","institution":"Children's Hospital Affiliated of Zhengzhou University: Zhengzhou Children's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Kairui","middleName":"","lastName":"Yang","suffix":""},{"id":493620722,"identity":"d1130126-5c21-4768-a43b-a3d4a3c5b0d3","order_by":4,"name":"Zhidan Yv","email":"","orcid":"","institution":"Children's Hospital Affiliated of Zhengzhou University: Zhengzhou Children's Hospital","correspondingAuthor":false,"prefix":"","firstName":"Zhidan","middleName":"","lastName":"Yv","suffix":""},{"id":493620723,"identity":"7d3f6dee-5455-4388-92fd-ffdf479b3387","order_by":5,"name":"Fang Zhou","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7ElEQVRIiWNgGAWjYDACCSCuAGL7442NDz4Y2NgRp+UMiHHm8GHDGQVpySRouZGWJszz4RBjAyEd8rObj0kcqLlj19hzxozZxuAAMwP74aMb8GlhnHMsTeLAsWfJzew9Zo9zDO7wMfCkpd3Ap4VZIsdM+gPb4WQ2njPmxjkGz5gZJHjM8GphA2qROPDvcDIPSK+FwWHGBkJaQColDrYdtpOQSEuTZiBGC1BlssXBvsMJBjzAQO4xSAO6kIBf5GckH7xx4NthewN2YFT++GNjx89++BheLTCQ2AD3HTHKQcCeWIWjYBSMglEwAgEAUAtO3NhnHv8AAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0003-0722-4253","institution":"Children's Hospital Affiliated of Zhengzhou University: Zhengzhou Children's Hospital","correspondingAuthor":true,"prefix":"","firstName":"Fang","middleName":"","lastName":"Zhou","suffix":""}],"badges":[],"createdAt":"2025-04-21 07:15:40","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6493389/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6493389/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88421389,"identity":"9c2bd086-cc40-445b-a918-5b8244d34fe6","added_by":"auto","created_at":"2025-08-06 09:28:30","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":262663,"visible":true,"origin":"","legend":"\u003cp\u003eGenetic Mutation Profile\u003c/p\u003e\n\u003cp\u003eA: Genetic Mutation Profileof Patient 1 showing c.866delA: p.H289Pfs* 3 variant.\u003c/p\u003e\n\u003cp\u003eB: Genetic Mutation Profileof Patient 2 showing c.1243_1247delAAAAC: p.N416Tfs* 11 variant.\u003c/p\u003e\n\u003cp\u003eC-D: Genetic Mutation Profile of Patient 2 showing c.349G\u0026gt;C: p.A117P variant and c.482G\u0026gt;A: p.R161Q variant.\u003c/p\u003e\n\u003cp\u003eE: Genetic Mutation Profile of Patient 3 showing chr6: 136693638_138817508del variant.\u003c/p\u003e\n\u003cp\u003eF: Genetic Mutation Profile of Patient 4 showing c.133C\u0026gt;T: p.R45X variant.\u003c/p\u003e\n\u003cp\u003eG: Genetic Mutation Profile of Patient 5 showing c.1903_1906delAAAC: p.K635fs* 61 variant.\u003c/p\u003e","description":"","filename":"1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6493389/v1/2697d0e0db8e32823de09f6f.jpg"},{"id":88421388,"identity":"441f996f-38f7-48cb-adca-04dba13da0fb","added_by":"auto","created_at":"2025-08-06 09:28:29","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":61494,"visible":true,"origin":"","legend":"\u003cp\u003eEndoscopic characteristics\u003c/p\u003e\n\u003cp\u003eA:Multiple ulcers in the descending colon in patient 1.\u003c/p\u003e\n\u003cp\u003eB:Multiple ulcers in the ascending colon in patient 2.\u003c/p\u003e\n\u003cp\u003eC: Multiple ulcers in the transverse colon in patient 3.\u003c/p\u003e\n\u003cp\u003eD: Multiple ulcers in the descending colon in patient 4.\u003c/p\u003e\n\u003cp\u003eE: Multiple ulcers in the ileumecal valve in patient 5.\u003c/p\u003e","description":"","filename":"2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6493389/v1/0f680b2ee336267f27a6f8fd.jpg"},{"id":88421393,"identity":"8a71161f-6ecb-4418-9b07-30c8ed91754e","added_by":"auto","created_at":"2025-08-06 09:28:30","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":112944,"visible":true,"origin":"","legend":"\u003cp\u003eThe locations of variants in the \u003cem\u003eTNFAIP3\u003c/em\u003e gene\u003c/p\u003e\n\u003cp\u003eThe black represents the frameshift mutation\u003c/p\u003e\n\u003cp\u003eThe red represents the missense mutation\u003c/p\u003e\n\u003cp\u003eThe green represents the nonsense mutation\u003c/p\u003e\n\u003cp\u003eThe purple represents the splicing mutation\u003c/p\u003e\n\u003cp\u003eThe blue represents the duplication mutation\u003c/p\u003e","description":"","filename":"3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6493389/v1/4a4bcec75dad19211abb9df7.jpg"},{"id":88426013,"identity":"7668232b-7c3e-46c6-89b4-a55f45bb0f94","added_by":"auto","created_at":"2025-08-06 10:00:30","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":903647,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6493389/v1/88b14d0c-ade4-4563-9764-465e8ef2da2b.pdf"}],"financialInterests":"","formattedTitle":"Haploinsufficiency of A20 caused by heterozygous mutations in the TNFAIP3 gene:A Case Series","fulltext":[{"header":"Introduction","content":"\u003cp\u003eHA20 (Haploinsufficiency of A20) was first reported in 2016 by Zhou et al\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. To date, over 100 cases have been documented, predominantly among Japanese populations, with relatively fewer reports from China. HA20 is an autosomal dominant hereditary disorder caused by pathogenic mutations in the tumor necrosis factor (TNF)-α-induced protein 3 gene (\u003cem\u003eTNFAIP3\u003c/em\u003e) \u003csup\u003e[\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. The A20 protein, encoded by \u003cem\u003eTNFAIP3\u003c/em\u003e, contains two functional domains: the N-terminal OTU domain and the C-terminal ZnF (zinc finger) domain, both of which play critical roles in regulating the nuclear factor κB (NF-κB) signaling pathway. Specifically, A20 facilitates the degradation of activated NF-κB through ubiquitination, thereby inhibiting inflammatory responses. In HA20 patients, mutations in \u003cem\u003eTNFAIP3\u003c/em\u003e typically result in loss-of-function of the A20 protein, leading to dysregulation of the NF-κB pathway and subsequent recurrent autoinflammatory responses. These mutations often manifest as nonsense mutations, causing premature termination of A20 protein translation and production of a truncated, non-functional protein. Clinical manifestations of HA20 are diverse and include recurrent fever, diarrhea, oral and genital ulcers, uveitis, and vasculitis\u003csup\u003e[\u003cspan additionalcitationids=\"CR6 CR7 CR8 CR9 CR10\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e. When these symptoms appear, especially in pediatric patients, HA20 should be considered as a differential diagnosis. Early-stage HA20 often presents with recurrent mucosal ulcers, necessitating differentiation from conditions such as rheumatoid arthritis, juvenile idiopathic arthritis, periodic fever with aphthous stomatitis, pharyngitis, and adenitis (PFAPA), hyperimmunoglobulinemia D syndrome (HIDS), and inflammatory bowel disease. Whole-exome sequencing (WES) aids clinicians in identifying \u003cem\u003eTNFAIP3\u003c/em\u003e mutations, thus confirming the diagnosis of HA20.\u003c/p\u003e\u003cp\u003eSeveral studies highlight that clinical presentations of HA20 can vary even among patients with identical mutations or within the same family. Moreover, patients with the same pathogenic variant may respond differently to the same treatment regimen, suggesting that other genetic or environmental factors may influence HA20 pathogenesis. Currently, there is no standardized treatment approach for HA20. While most children respond well to glucocorticoids, long-term use is associated with significant side effects. Colchicine therapy has shown efficacy in mild to moderate cases. Treatment selection appears to depend on the patient's primary clinical phenotype. Responses to immunosuppressive agents (methotrexate, cyclosporine, hydroxychloroquine, thalidomide, tacrolimus, and malacenthol) have been variable. For refractory cases, biologics (TNF-α inhibitors, anti-IL-1 drugs, anti-IL-6 drugs, and JAK inhibitors) offer potential new treatment options\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. A minority of patients have achieved remission through hematopoietic stem cell transplantation (HSCT), including both autologous and allogeneic transplants. Given the limited number of HA20 studies, clear diagnostic criteria have yet to be established. Gene sequencing combined with clinical manifestations can assist in diagnosis. This study analyzed the clinical and genetic data of five unrelated Chinese families to enhance understanding of HA20 diagnosis and treatment.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eA retrospective analysis was conducted on five children diagnosed with HA20 at Henan Children's Hospital between April 2019 and August 2023. Informed consent was obtained from all legal guardians to review the electronic medical records of the diagnosed children. Genetic testing data from whole-exome sequencing (WES), along with demographic, clinical, and laboratory data, were collected for each child. Imaging results, including ultrasound and magnetic resonance imaging, and gastrointestinal findings were also reviewed for some patients. The course of illness, symptom exacerbation and relief, targeted drug usage (corticosteroids, infliximab, adalimumab, etc. ), symptom changes, and treatment outcomes post-discharge were recorded.\u003c/p\u003e"},{"header":"Case series","content":"\u003cp\u003eDemographic and Clinical Characteristics\u003c/p\u003e\u003cp\u003eFive children with HA20 were confirmed in the Gastroenterology Department of Henan Children's Hospital between April 2019 and August 2023. Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e summarizes their baseline demographics and clinical characteristics and treatment follow-up. All patients aged from 2 to 10 years and experienced childhood-onset symptoms, with two female and three male patients. None of the patients reported a family history of genetic disorders or any special allergies. All five children with HA20 exhibited common symptoms of recurrent fever and gastrointestinal symptoms, including abdominal pain, diarrhoea and gastrointestinal ulcers at the onset of the disease. Oral ulcers were observed in three patients (60%), skin lesions on the extremities and trunk in two patients (40%), genital ulcers in one patient (20%) and arthritis in one patient (20%). In routine blood tests, inflammatory markers (CRP, ESR) were elevated in all five children. Notably, CRP levels were particularly high in cases 2, 3 and 4, while significant hematological sedimentation was observed in cases 1, 3 and 5 (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) .\u003c/p\u003e\u003cp\u003eCharacteristics of mutant genes\u003c/p\u003e\u003cp\u003eGenomic testing revealed heterozygous mutations in the \u003cem\u003eTNFAIP3\u003c/em\u003e gene among the five patients (Fig.\u0026nbsp;1). Specifically, Patient 4 exhibited a nonsense mutation characterized by a base substitution of c.133C \u0026gt; T, resulting in an amino acid sequence alteration of p.R45X. Patient 3 presented with a large segmental deletion, detailed as chr6: 136693638_138817508del. Patients 1, patient 2 and patient 5 showed frameshift mutations including c.866delA: p.H289Pfs* 3, c.1243_1247delAAAAC: p.N416Tfs* 11, c.1903_1906delAAAC: p.K635fs* 61. Further analysis indicated that the mutations in Patients 1, 2, 4, and 5 were de novo, while the three mutations in Patient 3 were inherited from the mother. Mutations in patients 3 and 5 have not been reported.\u003c/p\u003e\u003cp\u003eEndoscopic characteristics\u003c/p\u003e\u003cp\u003eGastrointestinal ulcers are a common issue in children with HA20, varying in location and severity (Fig.\u0026nbsp;2). Specifically, patients 1, 2, and 3 exhibited multiple ulcers in the colon and rectum. Patient 4 had ulcers in the transverse colon, descending colon, sigmoid colon, and rectum. Patient 5 presented with ulcers in the ileocecum, ascending colon, transverse colon, and descending colon.\u003c/p\u003e\u003cp\u003eTreatment and follow-up\u003c/p\u003e\u003cp\u003ePatient 1 developed severe hormone-dependent allergic reactions during treatment with glucocorticoids, thalidomide, and infliximab. Symptoms improved after switching to adalimumab. Patients 2, 3, and 5 were treated with corticosteroids and thalidomide. Patient 4 underwent surgical repair for jejunal perforation and was subsequently treated with oral thalidomide. Additionally, patient 2 was diagnosed with HA20 and methylmalonic aciduria (MMA) and received hydroxocobalamin (1 mg daily). After one week, urine organic acid screening and blood homocysteine levels normalized, and hydroxocobalamin dosage was tapered to 1.5 mg weekly. Patients 4, 2, and 3 were followed up for 3 years and 4 months, 3 years, and 1 year, respectively, with complete resolution of symptoms. Patient 1 was followed for 2 years and 3 months, showing improvement in digestive tract symptoms but persistent cecal ulcers. Patient 5 experienced improvement in gastrointestinal symptoms after one month.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWe conducted a systematic literature review of articles reporting \u003cem\u003eTNFAIP3\u003c/em\u003e mutations from 2016 to January 2024\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/sup\u003e. We conducted a systematic literature review of articles reporting \u003cem\u003eTNFAIP3\u003c/em\u003e mutations from 2016 to January 2024. A total of 168 patients from 85 families with genetically confirmed HA20 were included, excluding those with additional gene mutations or incomplete data. The cohort comprised 61 males and 101 females, with the earliest onset at five days and the longest disease duration exceeding 60 years. Mutation sites in the \u003cem\u003eTNFAIP3\u003c/em\u003e gene varied widely (Fig.\u0026nbsp;3)\u003csup\u003e[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e. The \u003cem\u003eTNFAIP3\u003c/em\u003e gene encodes the A20 protein, which plays a crucial role in regulating NF-κB signaling. Aberrant activation of NF-κB signaling is closely associated with multiple autoimmune diseases\u003csup\u003e[\u003cspan additionalcitationids=\"CR18\" citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]\u003c/sup\u003e. Therefore, these mutations may impair A20 protein function, affecting NF-κB regulation and increasing the risk of autoimmune diseases\u003csup\u003e[\u003cspan additionalcitationids=\"CR21\" citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e. Notably, despite all patients having heterozygous \u003cem\u003eTNFAIP3\u003c/em\u003e mutations, clinical manifestations varied, likely due to differences in mutation type, location, and genetic background. For instance, segmental deletions in patient 3 may affect a broader region of the gene with more complex physiological effects, while spontaneous mutations in patients 1, 2, 4, and 5 may result in varying degrees of impaired A20 function. Future studies will explore how these mutations influence clinical presentation and treatment response, aiding in understanding disease pathogenesis and improving treatment options.\u003c/p\u003e\u003cp\u003eClinical phenotypic differences in HA20 are not solely determined by genetic mutation sites. A20 is a highly conserved protein with two domains: the amino-terminal OTU domain and seven carboxyl-terminal ZnF domains\u003csup\u003e[\u003cspan additionalcitationids=\"CR24\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e. Patients with impaired OTU or ZnF domains alone do not develop ocular dysfunction, atrophic gastritis, or dental abnormalities. Specifically, OTU domain mutations do not cause musculoskeletal disease, autoimmune thyroid disease, liver injury, recurrent respiratory infections, or interstitial lung disease, while ZnF domain mutations do not lead to kidney injury or other symptom variations. Thus, clinical phenotype variation may be influenced by modifier genes and/or environmental factors. Mutations in ZnF domains correlate with earlier HA20 onset compared to OTU domain mutations. Studies show that patients in the OTU group (median onset age: 10 years, IQR: 8\u0026ndash;14) have later onset than those in the ZnF group (median onset age: 2.5 years, IQR: 0.6\u0026ndash;5). In our study, three \u003cem\u003eTNFAIP3\u003c/em\u003e variants affected the ZnF domain (patients 2, 3, 5), with onset ages of 6 months, 1 year 7 months, and 1 year 6 months, consistent with Chen's study. Two variants affected the OTU domain (patients 1, 4), with onset ages of five years and shortly after birth. The small sample size in this study led to discrepancies with the median onset age of the OTU group in Chen's study. Chen also observed diverse clinical manifestations in HA20 patients evaluated for his study\u003csup\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]\u003c/sup\u003e. Specifically, the most common symptom was oral ulcers (70%), followed by recurrent fever (42%), gastrointestinal ulcers (40%), skin lesions (38%), genital ulcers (36%), and musculoskeletal disorders (34%). In contrast, in this report, recurrent fever was the most frequent symptom (100%), followed by gastrointestinal ulcers (80%), oral ulcers (60%), skin lesions (40%), musculoskeletal disorders (20%), and genital ulcers (20%). These discrepancies from previous literature may be attributed to the small sample size.\u003c/p\u003e\u003cp\u003eHA20 must also be differentiated from other diseases such as Beh\u0026ccedil;et's disease (BS)\u003csup\u003e[\u003cspan additionalcitationids=\"CR28\" citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]\u003c/sup\u003e. Many clinical features of HA20 are similar to BS, including oral ulcers, genital ulcers, gastrointestinal ulcers, and skin lesions\u003csup\u003e[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]\u003c/sup\u003e, leading to initial misdiagnosis. For instance, patient 1 and patient 4 exhibited gastrointestinal ulcers; patient 2 had rash, gastrointestinal ulcers, and oral ulcers; patient 3 presented with rash, gastrointestinal ulcers, and perianal ulcers, all of which can be easily confused with BS. The median age at onset for HA20 patients was 5.92 years (IQR: 1\u0026ndash;10), typically occurring in early childhood, whereas BS usually manifests in early adulthood. Recurrent fever, severe intestinal inflammation, elevated acute phase reactants, and fluctuations in autoantibodies are less common in BS patients\u003csup\u003e[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]\u003c/sup\u003e. Infantile-onset inflammatory bowel disease (IBD) with perianal lesions is a form of monogenic IBD, and some HA20 cases exhibit varying degrees of perianal lesions, including severe perianal fistula. A rare disease study identified a 187 kb de novo microdeletion in the \u003cem\u003eTNFAIP3\u003c/em\u003e gene in an infant with infantile-onset IBD and perianal lesions, leading to a diagnosis of HA20\u003csup\u003e[\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]\u003c/sup\u003e. Therefore, HA20 should be differentiated from infantile-onset IBD with perianal lesions, and CNV analysis should be considered alongside whole exome sequencing (WES) to assess \u003cem\u003eTNFAIP3\u003c/em\u003e loss\u003csup\u003e[\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]\u003c/sup\u003e. This approach provides more comprehensive genetic information for accurate diagnosis and treatment. Familial Mediterranean fever (FMF), caused by biallelic mutations in exon 10 of the MEFV gene, is characterized by recurrent fever, abdominal pain, and joint inflammation. Although HA20 and FMF share clinical similarities and both develop in early childhood, they are distinct autoinflammatory diseases. Treatment strategies also overlap, with most FMF patients responding well to colchicine, while a minority require IL-1 blockers. Given that HA20 patients exhibit excessive production of pro-inflammatory cytokines\u003csup\u003e[\u003cspan additionalcitationids=\"CR35\" citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]\u003c/sup\u003e, biologics targeting cytokines effectively inhibit systemic inflammatory responses, These include anti-TNF-α agents (infliximab, adalimumab), anti-IL-1 agents (anakinra, canakinumab), and anti-IL-6 agents (tocilizumab). Corticosteroids are routinely used for symptomatic control, and some patients respond to colchicine therapy, either alone or in combination with glucocorticoids or mesalazine\u003csup\u003e[\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]\u003c/sup\u003e. Other immunotherapies, such as anti-CD20 monoclonal antibodies (rituximab), JAK-1 and \u0026minus;\u0026thinsp;3 inhibitors (tofacitinib), and thalidomide, have also been widely used\u003csup\u003e[\u003cspan additionalcitationids=\"CR39\" citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e]\u003c/sup\u003e. Hematopoietic stem cell transplantation can be considered for severe refractory cases.\u003c/p\u003e\u003cp\u003ePatient 2 had methylmalonic acidemia (MMA) from infancy. Early genetic testing, diagnosis, and treatment are crucial for managing such complex diseases. Patients with both HA20 and MMA provide valuable clinical insights into HA20, although this case is not representative of the general pediatric population. HA20 exhibits highly variable clinical manifestations, making clinical diagnosis challenging. Gene sequencing is essential for definitive diagnosis. This study has improved our understanding and diagnostic and therapeutic approaches. Accumulating more patient data will help establish phenotypes associated with the A20 genotype and provide a basis for clinical management.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eACMG, American College of Medical Genetics and Genomics; ANA, antinuclear antibody; BS, Beasccet\u0026apos;s disease; CRP, C-reactive protein; CMV, cytomegalovirus; CD, Cluster of Differentiation; CoA, coenzyme; CNKI, China National Knowledge Infrastructure; DUB, deubiquitinase; EBV, Epstein-Barr virus; ESR, erythrocyte sedimentation rate; HA20, haploinsufficiency of A20; Ig, Immunoglobulin; IL, interleukin; IQR, interquartile range; JAK, Janus kinase; MMA, Methylmalonic Acidaemia; NEMO, nuclear factor-\u0026kappa;-gene binding essential modulator; (NF)-\u0026kappa;B, nuclear factor-\u0026kappa;-gene binding; OUT, ovarian tumour; TNFAIP3, tumor necrosis factor alpha induced protein 3; WES, Whole exome sequencing;WBC, white blood cell; ZnF, zinc finger; \u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eEthics approval and consent to participate\u003c/p\u003e\n\u003cp\u003eEthical approval was waived by the local Ethics Committee of University Zhengzhou in view of the retrospective nature of the study and all the procedures being performed were part of the routine care.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eConsent for publication\u003c/p\u003e\n\u003cp\u003ePatients signed informed consent regarding publishing their data and photographs.\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials\u003c/p\u003e\n\u003cp\u003eThe dataset(s) supporting the conclusions of this article is(are) included within the article (and its additional file(s)).\u003c/p\u003e\n\u003cp\u003eCompeting interests\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eThis work was supported by Key Medical Science and Technology Project of Henan Province (NO.SBGJ202002125) and Henan Provincial Science and Technology Plan Project (NO.232102311124).\u003c/p\u003e\n\u003cp\u003eAuthors\u0026apos; contributions\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAll authors contributed to the study conception and design. Material preparation, data collection and analysis were performed by\u0026nbsp;\u003c/em\u003eYijing Liu\u003cem\u003e,\u0026nbsp;\u003c/em\u003eMengJun Dong\u003cem\u003e\u0026nbsp;and\u0026nbsp;\u003c/em\u003eKairui Yang\u003cem\u003e. The first draft of the manuscript was written by\u0026nbsp;\u003c/em\u003eHengpan Yao \u003cem\u003eand all authors commented on previous versions of the manuscript.\u003c/em\u003eFang Zhou and Zhidan Yv\u003cem\u003eedited the manuscript\u003c/em\u003e\u003cem\u003e.\u003c/em\u003e\u003cem\u003e\u0026nbsp;All authors read and approved the final manuscript\u003c/em\u003e\u003cem\u003e.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eAcknowledgements\u003c/p\u003e\n\u003cp\u003eFirst of all, l would like to give my heartfelt thanks to all thepeople who have ever helped me in this paper. My sincere and hearty thanks and appreciations go frstly to my supervisor, Ms. Fang Zhou, whose suggestions and encouragement have given me much insight into these translation studies. lt has been a great privilege and joy to study under his guidance and supervision. l am also extremely grateful to all my friends who have kindly provided me assistance and companionship in thecourse of preparing this paper. In addition, many thanks go to my family for their unfailing loveand unwavering support. Finally, l am really grateful to all those who devote much time toreading this thesis and give me much advice, Which will benefit mein my later study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eZhou Q, Wang H, Schwartz DM, et al. Loss-of-function mutations in TNFAIP3 leading to A20 haploinsufficiency cause an early-onset autoinflammatory disease. Nat Genet. 2016. 48(1): 67-73.\u003c/li\u003e\n\u003cli\u003eKim HY, Song JY, Kim WI, et al. 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Two distinct ubiquitin-binding motifs in A20 mediate its anti-inflammatory and cell-protective activities. Nat Immunol. 2020. 21(4): 381-387.\u003c/li\u003e\n\u003cli\u003eBagyinszky E, An S. Genetic Mutations Associated With TNFAIP3 (A20) Haploinsufficiency and Their Impact on Inflammatory Diseases. Int J Mol Sci. 2024. 25(15): 8275.\u003c/li\u003e\n\u003cli\u003eLi GM, Liu HM, Guan WZ, Xu H, Wu BB, Sun L. Expanding the spectrum of A20 haploinsufficiency in two Chinese families: cases report. BMC Med Genet. 2019. 20(1): 124.\u003c/li\u003e\n\u003cli\u003eWu Y, He X, Huang N, Yu J, Shao B. A20: a master regulator of arthritis. Arthritis Res Ther. 2020. 22(1): 220.\u003c/li\u003e\n\u003cli\u003eKarri U, Harasimowicz M, Carpio Tumba M, Schwartz DM. The Complexity of Being A20: From Biological Functions to Genetic Associations. J Clin Immunol. 2024. 44(3): 76.\u003c/li\u003e\n\u003cli\u003eChen Y, Ye Z, Chen L, et al. Association of Clinical Phenotypes in Haploinsufficiency A20 (HA20) With Disrupted Domains of A20. Front Immunol. 2020. 11: 574992.\u003c/li\u003e\n\u003cli\u003eShiraki M, Kadowaki S, Kadowaki T, Kawamoto N, Ohnishi H. Primary Immunodeficiency Disease Mimicking Pediatric Bechet\u0026apos;s Disease. Children (Basel). 2021. 8(2): 75.\u003c/li\u003e\n\u003cli\u003eLv Q, Li Y, Wei Q, et al. Autoinflammatory syndromes mimicking Beh\u0026ccedil;et\u0026apos;s disease with gastrointestinal involvement: a retrospective analysis. Clin Exp Rheumatol. 2024. 42(10): 2076-2085.\u003c/li\u003e\n\u003cli\u003eOhnishi H, Kawamoto N, Seishima M, Ohara O, Fukao T. A Japanese family case with juvenile onset Beh\u0026ccedil;et\u0026apos;s disease caused by TNFAIP3 mutation. Allergol Int. 2017. 66(1): 146-148.\u003c/li\u003e\n\u003cli\u003ePerazzio SF, Allenspach EJ, Eklund KK, et al. Beh\u0026ccedil;et disease (BD) and BD-like clinical phenotypes: NF-\u0026kappa;B pathway in mucosal ulcerating diseases. Scand J Immunol. 2020. 92(5): e12973.\u003c/li\u003e\n\u003cli\u003eKadowaki T, Kadowaki S, Ohnishi H. A20 Haploinsufficiency in East Asia. Front Immunol. 2021. 12: 780689.\u003c/li\u003e\n\u003cli\u003eTaniguchi K, Inoue M, Arai K, et al. Novel TNFAIP3 microdeletion in a girl with infantile-onset inflammatory bowel disease complicated by a severe perianal lesion. Hum Genome Var. 2021. 8(1): 1.\u003c/li\u003e\n\u003cli\u003eChen Y, Huang H, He Y, et al. A20 Haploinsufficiency in a Chinese Patient With Intestinal Behcet\u0026apos;s Disease-Like Symptoms: A Case Report. Front Immunol. 2020. 11: 1414.\u003c/li\u003e\n\u003cli\u003eYan M, Li D, Aknai S, Zhu H, Abudureyim M. Mutation analysis of the TNFAIP3 in A20 haploinsufficiency: A case report. Medicine (Baltimore). 2021. 100(20): e25954.\u003c/li\u003e\n\u003cli\u003eMartens A, van Loo G. A20 at the Crossroads of Cell Death, Inflammation, and Autoimmunity. Cold Spring Harb Perspect Biol. 2020. 12(1): a036418.\u003c/li\u003e\n\u003cli\u003eYu MP, Xu XS, Zhou Q, Deuitch N, Lu MP. Haploinsufficiency of A20 (HA20): updates on the genetics, phenotype, pathogenesis and treatment. World J Pediatr. 2020. 16(6): 575-584.\u003c/li\u003e\n\u003cli\u003eLiu J, Lin Y, Li X, et al. Haploinsufficiency of A20 in a Chinese child caused by loss-of-function mutations in TNFAIP3: A case report and review of the literature. Front Pediatr. 2022. 10: 990008.\u003c/li\u003e\n\u003cli\u003eShaheen ZR, Williams S, Binstadt BA. Case Report: A Novel TNFAIP3 Mutation Causing Haploinsufficiency of A20 With a Lupus-Like Phenotype. Front Immunol. 2021. 12: 629457.\u003c/li\u003e\n\u003cli\u003eDeshayes S, Bazille C, El Khouri E, et al. Chronic hepatic involvement in the clinical spectrum of A20 haploinsufficiency. Liver Int. 2021. 41(8): 1894-1900.\u003c/li\u003e\n\u003cli\u003eZhang C, Yu Z, Gao S, et al. Efficacy and safety of thalidomide in children with monogenic autoinflammatory diseases: a single-center, real-world-evidence study. Pediatr Rheumatol Online J. 2023. 21(1): 124.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"566\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" style=\"width: 566px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 1.\u0026nbsp;\u003c/strong\u003eCharacteristics of patients with\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eTNFAIP3 mutations\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"29\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCharacteristics\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"29\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eGenotype\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003ec.866delA: p.H289Pfs* 3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003ec.1243_1247delAAAAC: p.N416Tfs* 11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003echr6: 136693638_138817508del\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003ec.133C\u0026gt;T: p.R45X\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003ec.1903_1906delAAAC:\u003cbr\u003e\u0026nbsp;p.K635fs* 61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"100\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eSex\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"29\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 85px;\"\u003e\n \u003cp\u003eAge at genetic diagnosis (years)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 100px;\"\u003e\n \u003cp\u003e5y8m\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 86px;\"\u003e\n \u003cp\u003e6m\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 106px;\"\u003e\n \u003cp\u003e2y7m\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 85px;\"\u003e\n \u003cp\u003e10m\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 104px;\"\u003e\n \u003cp\u003e1y6m\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"31\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd height=\"38\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eRecurrent fever\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"29\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eOral ulcers\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"29\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eGenital ulcers\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"29\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eSkin lesions\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"42\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" style=\"width: 85px;\"\u003e\n \u003cp\u003eGastrointestinal\u0026nbsp;\u003cbr\u003e\u0026nbsp;lesions\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 100px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 86px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 106px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 85px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" style=\"width: 104px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"31\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd height=\"31\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eArthritis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003eYES\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eNO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"29\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eTreatment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003eThalidomide,\u003cbr\u003e\u0026nbsp;glucocorticoid, infliximab, adalimumab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eThalidomide,\u003cbr\u003e\u0026nbsp;glucocorticoid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003eThalidomide,\u003cbr\u003e\u0026nbsp;glucocorticoid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eThalidomide\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003eThalidomide,\u003cbr\u003e\u0026nbsp;glucocorticoid\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"124\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003eFollow-up\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 100px;\"\u003e\n \u003cp\u003e2y3m;\u003cbr\u003e\u0026nbsp;There is an ulcer\u0026nbsp;\u003cbr\u003e\u0026nbsp;in the ileocecal region\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e3y;\u003cbr\u003e\u0026nbsp;Symptoms and endoscopic findings were completely relieved\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 106px;\"\u003e\n \u003cp\u003e1y;\u003cbr\u003e\u0026nbsp;Symptoms and endoscopic findings\u003cbr\u003e\u0026nbsp; were completely relieved\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 85px;\"\u003e\n \u003cp\u003e3y4m;\u003cbr\u003e\u0026nbsp;Symptoms and endoscopic findings\u003cbr\u003e\u0026nbsp; were completely relieved\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 104px;\"\u003e\n \u003cp\u003e1m;\u003cbr\u003e\u0026nbsp;Symptoms were completely relieved\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"176\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" style=\"width: 566px;\"\u003e\n \u003cp\u003e\u003csup\u003ea\u003c/sup\u003e\u003csup\u003e\u0026nbsp;\u003c/sup\u003eF: Female;\u003csup\u003eb\u003c/sup\u003e M: Male;\u003csup\u003e\u0026nbsp;c\u003c/sup\u003ey: year; \u003csup\u003ed\u003c/sup\u003em: month;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd height=\"29\" style=\"width: 0px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"565\" class=\"fr-table-selection-hover\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"6\" style=\"width: 565px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003e2.\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eLaboratory findings of HA20 patients\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLaboratory findings\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 2\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 82px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 3\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 4\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePatient 5\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003eWBC (5~12 \u0026times; 109 /L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e13.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e20.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 82px;\"\u003e\n \u003cp\u003e18.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e13.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e10.98\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003eHemoglobin (11~16 g/dl)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e110\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 82px;\"\u003e\n \u003cp\u003e91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e94.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e103\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003ePlatelets (100~300 \u0026times; 109 /L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e303\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e221\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 82px;\"\u003e\n \u003cp\u003e378\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e454\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e304\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003eCRP (0~10.0 mg/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e15.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e43.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 82px;\"\u003e\n \u003cp\u003e99.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e108.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e12.25\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003eESR (0~15 mm/h)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e68\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 82px;\"\u003e\n \u003cp\u003e46\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e86\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003eIL-6 (0-7pg/mL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e35.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003e39.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 82px;\"\u003e\n \u003cp\u003e/\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e/\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e19.76\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 130px;\"\u003e\n \u003cp\u003eAutoantibodies\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003eNegative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 83px;\"\u003e\n \u003cp\u003eANA(1∶100)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 82px;\"\u003e\n \u003cp\u003eNegative\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 86px;\"\u003e\n \u003cp\u003e/\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 98px;\"\u003e\n \u003cp\u003e/\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"italian-journal-of-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"itjp","sideBox":"Learn more about [Italian Journal of Pediatrics](http://ijponline.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ITJP/default.aspx","title":"Italian Journal of Pediatrics","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"A20 haploinsufficiency, TNFAIP3, autoinflammatory diseases, heterozygous mutations","lastPublishedDoi":"10.21203/rs.3.rs-6493389/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6493389/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eObjectives Children with A20 haploinsufficiency, resulting from heterozygous mutations in the\u003cem\u003e TNFAIP3\u003c/em\u003egene, are increasingly being identified. However, their diagnosis and treatment remain challenging and are not yet fully optimized. The clinical, genetic characteristics and treatment methods of five children with HA20 from different families were collected from Henan Children's Hospital between April 2019 and August 2023 to evaluated for accumulating experience in the management of this rare condition.\u003c/p\u003e\n\u003cp\u003eResults We identified five heterozygous mutations inthe \u003cem\u003eTNFAIP3\u003c/em\u003egene among the five children, including c.866delA: p.H289Pfs* 3, c.1243_1247delAAAAC: p.N416Tfs* 11, chr6: 136693638_138817508del, c.133C\u0026gt;T: p.R45X, c.1903_1906delAAAC: p.K635fs* 61. The mutations in Patients 1, 2, 4, and 5 were de novo, while the three mutations in Patient 3 were inherited from the mother. Mutations in patients 3 and 5 have not been reported. All five patients presented with childhood-onset recurrent fever and intermittent diarrhea, which are hallmark features of HA20. Additionally, two of the five patients experienced intermittent bloody stool, three had oral ulcers, and two presented with skin symptoms, further aligning with the clinical manifestations of HA20. Laboratory tests revealed elevated inflammatory markers, including increased white blood cell (WBC) counts, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). Endoscopic observation, there were ulcers in different parts of the intestine. Each child was treated with the oral drug thalidomide, 4 children (80%) received glucocorticoids to reduce inflammation, and had different biological agents according to individual differences. During follow-up, we observed significant improvement in all children who received targeted treatment.\u003c/p\u003e\n\u003cp\u003eConclusions HA20 is a rare monogenic early-onset auto-inflammatory disease. It can present with a variety of clinical manifestations, including Behçet-like syndrome, inflammatory bowel disease, lupus-like syndrome and periodic fever syndrome. Whole-exome sequencing should be actively considered for children who present with early-onset symptoms or features suggestive of autoimmune diseases.\u003c/p\u003e","manuscriptTitle":"Haploinsufficiency of A20 caused by heterozygous mutations in the TNFAIP3 gene:A Case Series","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-06 09:28:25","doi":"10.21203/rs.3.rs-6493389/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewersInvited","content":"","date":"2025-07-31T08:49:30+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-05-01T13:16:27+00:00","index":"","fulltext":""},{"type":"submitted","content":"Italian Journal of Pediatrics","date":"2025-04-24T12:43:07+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"italian-journal-of-pediatrics","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"itjp","sideBox":"Learn more about [Italian Journal of Pediatrics](http://ijponline.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/ITJP/default.aspx","title":"Italian Journal of Pediatrics","twitterHandle":"@BioMedCentral","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"b7ba09b7-6b67-4fc3-b8c6-00a785dfa1e0","owner":[],"postedDate":"August 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-08-06T09:28:25+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-06 09:28:25","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6493389","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6493389","identity":"rs-6493389","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}