Blood Absolute Monocyte Count Trends in Preterm Infant with Suspected Necrotizing Enterocolitis, an Adjunct Tool for Diagnosis?

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Meghan Meghan, Michel Mikhael, Grant Shafer, W. Nathan Holmes, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3722321/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 01 Aug, 2024 Read the published version in Journal of Perinatology → Version 1 posted 9 You are reading this latest preprint version Abstract Objective We investigated the trends of blood absolute monocyte count (AMC) over 72 hours after suspecting necrotizing enterocolitis (NEC). Study Design A single center, retrospective study, the AMC was plotted over 72 hours after NEC evaluation. Receiver operating characteristic (ROC) curve analysis assessed change in AMC to identify absence of NEC and different NEC stages. Results In 130 infants, the AMC decreased in patients with NEC stage 2 or 3. Stages 2 and 3 NEC experienced a drop in AMC compared to an increase in no NEC, Stage 1, or positive culture (p<0.05). AMC increase 24% or less can differentiate NEC stage 2/3 from stage 1 with an area under the curve (AUC) of 0.78. There wasn’t statistical difference between any NEC and no NEC (AUC, 0.57). Discussion/Conclusions A decrease in AMC can be an adjunct biomarker to identify NEC stage 2 and 3, when compared to no NEC/stage 1. Health sciences/Health care/Diagnosis/Laboratory techniques and procedures Health sciences/Biomarkers/Diagnostic markers Absolute Monocyte Count Necrotizing Enterocolitis Pneumatosis Intestinalis Figures Figure 1 Figure 2 Figure 3 Introduction Necrotizing enterocolitis (NEC) is associated with significant morbidity and mortality in preterm infants ( 1 ). It is the most common surgical emergency in the neonatal intensive care unit (NICU), with an incidence of 6–10% ( 2 ). NEC mortality ranges between 20–40% ( 2 , 3 ). The associated morbidities include intestinal obstruction, liver failure, and malnutrition ( 4 – 6 ). There is also evidence that NEC negatively affects neurodevelopmental outcomes in preterm infants independently of other risk factors ( 7 ). Due to the limited knowledge of NEC pathophysiology, its nonspecific presentation, rapid progression, and its association with serious short- and long-term complications, there is a low threshold to suspect NEC based on vague manifestations. This may unnecessarily expose infants without NEC to antibiotics, diagnostic investigations, withholding of enteral nutrition, and prolonged hospital stay. Diagnosis of NEC is often challenging. Since it was first described in 1978, NEC has been classified according to Bell’s criteria, which categorizes NEC stages based on clinical and radiographic findings ( 4 , 8 , 9 ). Pneumatosis intestinalis and portal venous air are pathognomonic radiographic findings, combined with other imprecise radiological or clinical manifestations such as emesis, bloody stools, abdominal distention, and vital sign instability. Thus, Bell’s criteria cannot differentiate between NEC and other conditions, such as sepsis or feeding intolerance. Additionally, stage 1 NEC does not always progress to stage 2/3, leading many to believe that stage 1 NEC is a pre-NEC condition ( 4 , 8 ). Stage 3 NEC is easier to diagnose as it involves intestinal perforation, peritonitis, and severe systemic involvement ( 4 ). It is sometimes difficult to differentiate it from spontaneous intestinal perforation (SIP), as both could have pneumoperitoneum ( 10 ). Currently, no biomarker can reliably identify NEC ( 11 ). One theory for the etiology of NEC posits that intestinal epithelia damage and subsequent inflammatory cascades activate an influx of immune cells, including monocytes ( 12 , 13 ). Previous studies have shown that peripheral monocytes may be recruited to the intestine during an acute NEC episode ( 1 , 14 – 16 ). Desiraju et al. noted a correlation between the degree of AMC decrease and NEC severity. They concluded that percent AMC change may help identify NEC at onset and prognosticate disease severity ( 14 ). However, the AMC trend over time after suspected NEC has not been studied. This study investigates the trends of AMC over 72 hours after the onset of clinical suspicion of NEC in preterm infants and explores its utilization as an adjunct tool to rule out NEC. Methods This retrospective study included infants born at < 32-week gestation age (GA) admitted in the first 30 days of life between January 2011 and December 2021 who underwent a NEC diagnostic evaluation after the first week of life. We excluded infants with major congenital gastrointestinal anomalies and those transferred after the NEC evaluation was started at another hospital. The hospital's institutional review board approved the study. The outcome of NEC evaluation was determined based on a detailed review of the clinical course and radiological studies by neonatologist investigators (MM, GS, and MM) as follows. If a patient received two days of antibiotics and enteral feeds were resumed, along with normal imaging studies, they were considered to have no NEC. Those who received 7–10 days of antibiotics and feeds were held, with no definite pneumatosis intestinalis on imaging studies; they were considered to have stage 1 NEC. Infants with pneumatosis intestinalis who received 10–14 days of antibiotic treatment, were categorized as stage 2. Patients who underwent surgical intervention and/or had severe multiorgan failure were considered stage 3. Infants who died within 72 hours of onset of NEC suspicion with acute abdominal signs and no other apparent etiology were classified as death. According to the surgical findings and clinical picture, those with bowel perforation and no other signs of NEC, that is, younger age with minimal or no enteral feeds, were classified as having SIP. Infants with positive blood culture results were classified as having sepsis if there were no other signs of NEC. AMC was calculated from complete blood counts (CBC) by multiplying the total white blood cell count by the monocyte percentage. The AMC was then plotted for the baseline before the onset of illness and over 72 hours after the NEC evaluation. Statistical Analyses The study population was characterized by the median [IQR] for gestational age, birthweight, age of illness, and antibiotic duration. The Kruskal-Wallis test was used to evaluate the significance of distributional variations across groups, including pairwise comparisons. The significance of differences in the average AMC across time within each group was evaluated using gamma regression in the generalized linear mixed model (GLMM) procedure. We also analyzed the percentage change (delta) in AMC from baseline to NEC suspicion for infants with no NEC, those with NEC stages 1–3, those who died within 72 hours of work-up, and those with SIP or a positive culture. Receiver operating characteristic (ROC) curve analysis was performed to assess the percentage delta in AMC to identify the absence of NEC and different NEC stages. Imaging studies of infants with no NEC, stage 1 or stage 2, were also independently reviewed by two pediatric radiologists (AE and WNH). Radiologists were blinded to the clinical course of the infants and their evaluation was based on imaging alone. A comparison of NEC staging based on imaging only to a comprehensive review was performed, and percent agreement was reported. All analyses were performed using SPSS v29.0. Results A total of 1,296 preterm infants were admitted during the study duration. 338 infants’ records were reviewed for study eligibility based on antibiotic exposure, suggesting possible suspicion of NEC. Of the screened records, 130 infants underwent NEC evaluations that were ultimately included in the study, and their outcomes were evaluated (Table 1). A total of 208 infants were excluded for the following reasons: 113 received antibiotics for reasons other than NEC suspicion, six were excluded for gastrointestinal anomalies, 25 patients had NEC evaluation before seven days of life, and 64 patients had an evaluation for NEC that started at an outside hospital. Table 1 demonstrates that infants diagnosed with SIP or those who died were characterized by younger GA and lower birthweight than infants with no NEC or NEC stage 1–3 (p < 0.05). It also demonstrates that age at illness onset was significantly earlier in infants with SIP at a median of 12 days [IQR: 8.8, 17.2] compared to the longest at 35 days [IQR: 26.4, 43.3] in stage 3 NEC patients (p < 0.05). As expected, antibiotic days for NEC evaluation episodes increased with NEC disease stage from a median of 7 days [IQR: 7, 10] in infants with stage 1 NEC, 10 days [9.5, 14] with stage 2 NEC, and 21 days [14, 21] with stage 3 NEC (Table 1). In patients with NEC stage 2 or 3, the AMC dropped by an average of 43% of the baseline value at the onset of suspicion (mean rate ratio = 0.57 (95% CI 0.41, 0.80), with the lower levels continuing to be observed at follow-up (p < 0.05), Fig. 1 . However, this was not observed in the other groups. The percentage change in AMC from baseline to illness onset significantly differed by diagnosis, p = 0.008. Patients with stage 2 and 3 NEC experienced a significant decrease in AMC compared to those with no NEC, stage 1 NEC, or positive blood culture, who demonstrated an increase in AMC (p < 0.05; Fig. 2 ). ROC curve analysis was used to assess the validity of the percentage change in AMC from baseline to NEC suspicion in order to identify different stages of NEC (Fig. 3 ). An increase in AMC of 24% or less can differentiate NEC stage 2 or 3 from stage 1 with an area under the curve (AUC) of 0.78. A decrease in AMC of more than 32% can differentiate stage 2 or 3 vs. stage 1 or no NEC with an AUC of 0.71. There is no statistically significant difference between any NEC and no NEC (AUC 0.57). Radiologists reviewed the imaging studies of 93 infants with no NEC or stage 1/2 NEC. A comparison of NEC stages based on imaging only to stages based on comprehensive clinical revision is listed in table 2. There were 14 infants in whom imaging review identified possible stage 2 NEC, whereas their clinical outcomes suggested no NEC. The percentage of AMC change among these infants was compared to that in other infants with confirmed stage 2 NEC, yielding no statistically significant difference. The comparison showed a median change of -33% [IQR: -67, 13] for these infants, as opposed to -47% [IQR: -67, 10] for the latter group, p = 0.963. Discussion It has been previously shown that the percentage change in AMC may correlate with NEC severity ( 14 , 16 , 17 ). This study similarly demonstrates a decrease in the peripheral AMC in infants with stage 2 and 3 NEC, indicating that this can be an adjunct diagnostic tool. Comparing the AMC at the onset of illness to a prior baseline can increase the suspicion of whether a patient is developing NEC and help guide treatment plans in real-time. Complete blood counts, which include the monocyte count, are frequently obtained from preterm infants admitted to the NICU. Therefore, utilizing delta AMC as an adjunct biomarker is feasible in clinical settings with a quick turnaround time. Other biomarkers investigated for NEC are challenging to obtain in the clinical setting or nonspecific markers of inflammation, which could be elevated for alternative diagnoses such as sepsis ( 3 , 8 , 18 – 20 ). This study aimed to evaluate the AMC as a tool to delineate between no NEC and any NEC to improve diagnostic accuracy and efficiency. However, there was no statistically significant difference in AMC between no NEC and to all stages of NEC. The AMC in infants with stage 1 NEC increased rather than decreased, similar to that observed in infants with sepsis in our cohort. We reason that stage 1 NEC may not show the same decrease in monocyte count because this is a subjective diagnosis without well-defined criteria. Therefore, this group may include patients without intestinal inflammation, which is hypothesized to be the etiology of the lower AMC among infants with NEC. Stage 1 NEC may overlap with culture-negative sepsis in which body fluid cultures testing is negative, but there are other laboratory or clinical findings concerning for infection ( 21 ). The lack of change in AMC for stage 1 NEC may support the hypothesis by Gregory et al. and others that stage 1 NEC could be a pre-NEC condition and, therefore, would not experience a drop in AMC seen in proven NEC stage 2–3 ( 22 ). Our findings do not allow for a complete delineation of this hypothesis; however, further studies are required. This study has several limitations. As this was a retrospective review, variations were observed in the timing of the CBCs obtained. This study also does not consider aspects of care in the NICU. However, this was a single-institution study with a relatively uniform standard of care, as most of these infants were cared for in our extremely low birthweight infants’ program ( 23 ). Finally, a few patients underwent multiple NEC evaluations. However, only their first evaluations were included, and there was no statistical difference if the groups were broken down by subjects or by NEC evaluation episodes. Our study has several strengths. NEC staging was not based on a pre-existing database. However, the three neonatologist investigators reviewed the patients' records in detail a with consensus to determine the clinical outcome. Analysis of AMC also included patients who might have overlapping diagnoses such as SIP or sepsis to help better understand the role of AMC in differentiating between NEC and other conditions. In addition, blinded verification of NEC staging by two separate radiologists was performed. The results of our study reinforce that NEC remains a challenging diagnosis with a high risk of diagnostic error. Often defined as a missed opportunity to establish a timely, accurate diagnosis ( 24 ), diagnostic errors are expected when considering intra-abdominal pathology, such as NEC ( 25 ). However, the increasing availability of diagnostic testing in the NICU can lead to over-testing and over-diagnosis of NEC ( 26 ). This is complicated by the fact that the diagnostic process in the NICU, similar to other dynamic rapid-pace settings, is non-linear. Critically ill neonates may present with active deterioration, which requires prioritizing stabilization over a formal diagnostic evaluation. This highlights the need for continued study of potential biomarkers with high diagnostic accuracy and rapid turnaround time when clinicians suspect a patient is developing NEC. Our data also suggest that stage 1 NEC remains an elusive entity to define; however the heavy burden of overtreatment versus the risks of missed cases that may progress reinforces the need for additional diagnostic tools. Thus, future studies to better describe stage 1 NEC would help identify those with alternative etiologies, target treatment length, and improve antibiotic stewardship ( 27 , 28 ). Notably, 40 out of 50 (80%) infants with no NEC were suspected to have stage 1 or stage 2 NEC based on imaging studies only. This suggests the need for continued refinement of the radiological approach for diagnosing NEC. Recent improvements in ultrasound technology as a modality for NEC diagnosis are exciting ( 29 , 30 ), as pathognomonic radiological findings such as pneumatosis intestinalis were visualized more accurately with ultrasound than with X-rays ( 31 ). Future directions toward utilizing machine learning and artificial intelligence might augment the clinical capabilities for accurate and timely diagnosis of necrotizing enterocolitis( 32 ). Conclusions A decrease in the AMC over time can be used as an adjunctive biomarker to identify NEC stage 2 and 3, when compared to no NEC or stage 1 NEC. However, AMC values cannot be used to rule out NEC reliably, and future studies are needed to elucidate a reliable biomarker to rule out the presence of NEC. Declarations Statement of Ethics Study approval statement : The study protocol was reviewed and approved by Children’s Hospital of Orange County IRB Committee, IRB ID 1919772-1 internal number 200574. No ethics approval was needed. Consent to participate statement : This study was granted by the Children’s Hospital of Orange County IRB, an exemption from written informed consent given the retrospective nature of the study. Conflict of Interest Statement The authors have no conflicts of interest to declare. Funding Sources No funding sources to disclose. Author Contributions Drs. Moroze, Shafer, and Mikhael contributed to the conceptualization and design of the study, the collection, analysis, and interpretation of the data. They drafted the initial manuscript and approved the final manuscript as submitted. Mrs. Morphew and Dr. Sayrs contributed to the analysis and interpretation of the data. They contributed to all drafts of the manuscript and approved the final manuscript as submitted. Drs. Eghbal and Holmes contributed to the collection, analysis, and interpretation of the data. They contributed to all drafts of the manuscript and approved the final manuscript as submitted. 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Pediatr Res. 2023 Jan;93(2):376–81. Tables Tables 1-2 are available in the Supplementary Files section Additional Declarations There is NO conflict of interest to disclose. Supplementary Files Table1JPerinatologysubmission.jpg Table2JournalofPerinatologySubmission.jpg Cite Share Download PDF Status: Published Journal Publication published 01 Aug, 2024 Read the published version in Journal of Perinatology → Version 1 posted Editorial decision: revise 05 Feb, 2024 Review # 2 received at journal 25 Jan, 2024 Reviewer # 2 agreed at journal 18 Jan, 2024 Review # 1 received at journal 12 Jan, 2024 Reviewer # 1 agreed at journal 31 Dec, 2023 Reviewers invited by journal 26 Dec, 2023 Submission checks completed at journal 08 Dec, 2023 First submitted to journal 07 Dec, 2023 Editor assigned by journal 07 Dec, 2023 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-3722321","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":263546577,"identity":"cb15ddce-65bb-4bc7-9ad6-dfed0ecba591","order_by":0,"name":"Meghan Meghan","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzklEQVRIiWNgGAWjYDCCA3AWM4gpIUOKFrYEkBYeUrTwGIBJgjr4bh9g3XSj4p6cfHvP51c3aix4GNgPH92AT4vkuQS22zlnio0Ze85us845BnQYT1raDXxaDM4wsN3ObUtIbJbI3WacwwbUIsFjRpyWNvk3z4xz/pGipUeCh/lxbhsRWiTPMLYB/ZJgLMGTZsac2yfBw0bIL3xnmI/dzqlIAIbY4cefc77VyfGzHz6GVwsDA2MDjMUmASbxK0cFzB9IUT0KRsEoGAUjBwAARQhFfjoMH2YAAAAASUVORK5CYII=","orcid":"","institution":"Pediatrix Fort Worth Neonatology","correspondingAuthor":true,"prefix":"","firstName":"Meghan","middleName":"","lastName":"Meghan","suffix":""},{"id":263546578,"identity":"54988001-7242-4db9-bc4e-b38ac88a6ee2","order_by":1,"name":"Michel Mikhael","email":"","orcid":"https://orcid.org/0000-0001-8307-6569","institution":"Children's Hospital of Orange County","correspondingAuthor":false,"prefix":"","firstName":"Michel","middleName":"","lastName":"Mikhael","suffix":""},{"id":263546579,"identity":"4c238b67-090a-4c22-91bd-dc46b57d14db","order_by":2,"name":"Grant Shafer","email":"","orcid":"","institution":"Children's Hospital of Orange County","correspondingAuthor":false,"prefix":"","firstName":"Grant","middleName":"","lastName":"Shafer","suffix":""},{"id":263546580,"identity":"f51d0f4d-135a-42d5-88f3-c316deb5960d","order_by":3,"name":"W. Nathan Holmes","email":"","orcid":"","institution":"Children's Hospital of Orange County","correspondingAuthor":false,"prefix":"","firstName":"W.","middleName":"Nathan","lastName":"Holmes","suffix":""},{"id":263546581,"identity":"fcbf3d7f-f4de-4758-959c-bf3e17f31b5f","order_by":4,"name":"Azam Eghbal","email":"","orcid":"","institution":"Children's Hospital of Orange County","correspondingAuthor":false,"prefix":"","firstName":"Azam","middleName":"","lastName":"Eghbal","suffix":""},{"id":263546582,"identity":"e5fa5093-eb18-4844-9838-346829f04586","order_by":5,"name":"Tricia Morphew","email":"","orcid":"","institution":"Children's Hospital of Orange County","correspondingAuthor":false,"prefix":"","firstName":"Tricia","middleName":"","lastName":"Morphew","suffix":""},{"id":263546583,"identity":"c3a8a423-e591-468e-a8aa-b83b8209ebb7","order_by":6,"name":"Lois Sayrs","email":"","orcid":"https://orcid.org/0000-0003-1633-0576","institution":"Children's Hospital of Orange County","correspondingAuthor":false,"prefix":"","firstName":"Lois","middleName":"","lastName":"Sayrs","suffix":""}],"badges":[],"createdAt":"2023-12-07 20:45:07","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-3722321/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-3722321/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41372-024-02070-7","type":"published","date":"2024-08-01T04:00:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":49080087,"identity":"0c265dc7-e109-41ed-8ed3-542edd689f97","added_by":"auto","created_at":"2024-01-02 19:54:06","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":271735,"visible":true,"origin":"","legend":"\u003cp\u003eEvaluation of average AMC across time.\u003c/p\u003e","description":"","filename":"Figure1JournalofPerinatologysubmission.png","url":"https://assets-eu.researchsquare.com/files/rs-3722321/v1/0672b0a4e7e4910dd13df62f.png"},{"id":49080088,"identity":"95adfa54-b49d-4434-b442-9d20b5bd090b","added_by":"auto","created_at":"2024-01-02 19:54:06","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":154971,"visible":true,"origin":"","legend":"\u003cp\u003ePercentage change in AMC from baseline to illness onset.\u003c/p\u003e","description":"","filename":"Figure2JournalofPerinatologySubmission.png","url":"https://assets-eu.researchsquare.com/files/rs-3722321/v1/f287a54589ad3bb987b0d5d8.png"},{"id":49080091,"identity":"2b3c1257-6b26-4a54-9150-4ebd0f2b3b09","added_by":"auto","created_at":"2024-01-02 19:54:06","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":220643,"visible":true,"origin":"","legend":"\u003cp\u003eROC curve analyses to assess validity of percentage change in AMC from baseline to NEC suspicion to identify the following:\u003c/p\u003e\n\u003cp\u003eA. Stage 2 or 3 (+) vs. Stage 1 (-)\u003c/p\u003e\n\u003cp\u003eB. Stage 2 or 3 (+) vs. No NEC (-)\u003c/p\u003e\n\u003cp\u003eC. Stage 2 or 3 (+) vs. Stage 1 or No NEC (-)\u003c/p\u003e\n\u003cp\u003eD. Any NEC (+) vs. No NEC (-)\u003c/p\u003e","description":"","filename":"FIgure3JournalofPerinatologySubmission.png","url":"https://assets-eu.researchsquare.com/files/rs-3722321/v1/15f31e974389b6016b2af9b2.png"},{"id":61627468,"identity":"aa3e54b0-0e40-40ac-b934-c69597757578","added_by":"auto","created_at":"2024-08-02 07:06:28","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":839370,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-3722321/v1/06ddfd0d-b557-4d05-8e2e-e6f8c5b8ff5a.pdf"},{"id":49080090,"identity":"5b401452-cdb1-4731-a441-51bdcd490edb","added_by":"auto","created_at":"2024-01-02 19:54:06","extension":"jpg","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":129979,"visible":true,"origin":"","legend":"","description":"","filename":"Table1JPerinatologysubmission.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3722321/v1/f79f493a00d674e5c4874f7d.jpg"},{"id":49080089,"identity":"1e45e914-667c-4edd-8e8c-690b87375aa2","added_by":"auto","created_at":"2024-01-02 19:54:06","extension":"jpg","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":70881,"visible":true,"origin":"","legend":"","description":"","filename":"Table2JournalofPerinatologySubmission.jpg","url":"https://assets-eu.researchsquare.com/files/rs-3722321/v1/22e03d5d9be4c4710eae5c06.jpg"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e conflict of interest to disclose.","formattedTitle":"Blood Absolute Monocyte Count Trends in Preterm Infant with Suspected Necrotizing Enterocolitis, an Adjunct Tool for Diagnosis?","fulltext":[{"header":"Introduction","content":"\u003cp\u003eNecrotizing enterocolitis (NEC) is associated with significant morbidity and mortality in preterm infants (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e). It is the most common surgical emergency in the neonatal intensive care unit (NICU), with an incidence of 6\u0026ndash;10% (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e). NEC mortality ranges between 20\u0026ndash;40% (\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). The associated morbidities include intestinal obstruction, liver failure, and malnutrition (\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e). There is also evidence that NEC negatively affects neurodevelopmental outcomes in preterm infants independently of other risk factors (\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e). Due to the limited knowledge of NEC pathophysiology, its nonspecific presentation, rapid progression, and its association with serious short- and long-term complications, there is a low threshold to suspect NEC based on vague manifestations. This may unnecessarily expose infants without NEC to antibiotics, diagnostic investigations, withholding of enteral nutrition, and prolonged hospital stay.\u003c/p\u003e \u003cp\u003eDiagnosis of NEC is often challenging. Since it was first described in 1978, NEC has been classified according to Bell\u0026rsquo;s criteria, which categorizes NEC stages based on clinical and radiographic findings (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). Pneumatosis intestinalis and portal venous air are pathognomonic radiographic findings, combined with other imprecise radiological or clinical manifestations such as emesis, bloody stools, abdominal distention, and vital sign instability. Thus, Bell\u0026rsquo;s criteria cannot differentiate between NEC and other conditions, such as sepsis or feeding intolerance.\u003c/p\u003e \u003cp\u003eAdditionally, stage 1 NEC does not always progress to stage 2/3, leading many to believe that stage 1 NEC is a pre-NEC condition (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e). Stage 3 NEC is easier to diagnose as it involves intestinal perforation, peritonitis, and severe systemic involvement (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e). It is sometimes difficult to differentiate it from spontaneous intestinal perforation (SIP), as both could have pneumoperitoneum (\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eCurrently, no biomarker can reliably identify NEC (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). One theory for the etiology of NEC posits that intestinal epithelia damage and subsequent inflammatory cascades activate an influx of immune cells, including monocytes (\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e). Previous studies have shown that peripheral monocytes may be recruited to the intestine during an acute NEC episode (\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan additionalcitationids=\"CR15\" citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e). Desiraju et al. noted a correlation between the degree of AMC decrease and NEC severity. They concluded that percent AMC change may help identify NEC at onset and prognosticate disease severity (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). However, the AMC trend over time after suspected NEC has not been studied. This study investigates the trends of AMC over 72 hours after the onset of clinical suspicion of NEC in preterm infants and explores its utilization as an adjunct tool to rule out NEC.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eThis retrospective study included infants born at \u0026lt;\u0026thinsp;32-week gestation age (GA) admitted in the first 30 days of life between January 2011 and December 2021 who underwent a NEC diagnostic evaluation after the first week of life. We excluded infants with major congenital gastrointestinal anomalies and those transferred after the NEC evaluation was started at another hospital. The hospital's institutional review board approved the study.\u003c/p\u003e \u003cp\u003eThe outcome of NEC evaluation was determined based on a detailed review of the clinical course and radiological studies by neonatologist investigators (MM, GS, and MM) as follows. If a patient received two days of antibiotics and enteral feeds were resumed, along with normal imaging studies, they were considered to have no NEC. Those who received 7\u0026ndash;10 days of antibiotics and feeds were held, with no definite pneumatosis intestinalis on imaging studies; they were considered to have stage 1 NEC. Infants with pneumatosis intestinalis who received 10\u0026ndash;14 days of antibiotic treatment, were categorized as stage 2. Patients who underwent surgical intervention and/or had severe multiorgan failure were considered stage 3. Infants who died within 72 hours of onset of NEC suspicion with acute abdominal signs and no other apparent etiology were classified as death. According to the surgical findings and clinical picture, those with bowel perforation and no other signs of NEC, that is, younger age with minimal or no enteral feeds, were classified as having SIP. Infants with positive blood culture results were classified as having sepsis if there were no other signs of NEC.\u003c/p\u003e \u003cp\u003eAMC was calculated from complete blood counts (CBC) by multiplying the total white blood cell count by the monocyte percentage. The AMC was then plotted for the baseline before the onset of illness and over 72 hours after the NEC evaluation.\u003c/p\u003e \u003cp\u003eStatistical Analyses\u003c/p\u003e \u003cp\u003eThe study population was characterized by the median [IQR] for gestational age, birthweight, age of illness, and antibiotic duration. The Kruskal-Wallis test was used to evaluate the significance of distributional variations across groups, including pairwise comparisons. The significance of differences in the average AMC across time within each group was evaluated using gamma regression in the generalized linear mixed model (GLMM) procedure. We also analyzed the percentage change (delta) in AMC from baseline to NEC suspicion for infants with no NEC, those with NEC stages 1\u0026ndash;3, those who died within 72 hours of work-up, and those with SIP or a positive culture. Receiver operating characteristic (ROC) curve analysis was performed to assess the percentage delta in AMC to identify the absence of NEC and different NEC stages. Imaging studies of infants with no NEC, stage 1 or stage 2, were also independently reviewed by two pediatric radiologists (AE and WNH). Radiologists were blinded to the clinical course of the infants and their evaluation was based on imaging alone. A comparison of NEC staging based on imaging only to a comprehensive review was performed, and percent agreement was reported. All analyses were performed using SPSS v29.0.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 1,296 preterm infants were admitted during the study duration. 338 infants\u0026rsquo; records were reviewed for study eligibility based on antibiotic exposure, suggesting possible suspicion of NEC. Of the screened records, 130 infants underwent NEC evaluations that were ultimately included in the study, and their outcomes were evaluated (Table\u0026nbsp;1). A total of 208 infants were excluded for the following reasons: 113 received antibiotics for reasons other than NEC suspicion, six were excluded for gastrointestinal anomalies, 25 patients had NEC evaluation before seven days of life, and 64 patients had an evaluation for NEC that started at an outside hospital.\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;1 demonstrates that infants diagnosed with SIP or those who died were characterized by younger GA and lower birthweight than infants with no NEC or NEC stage 1\u0026ndash;3 (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). It also demonstrates that age at illness onset was significantly earlier in infants with SIP at a median of 12 days [IQR: 8.8, 17.2] compared to the longest at 35 days [IQR: 26.4, 43.3] in stage 3 NEC patients (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05). As expected, antibiotic days for NEC evaluation episodes increased with NEC disease stage from a median of 7 days [IQR: 7, 10] in infants with stage 1 NEC, 10 days [9.5, 14] with stage 2 NEC, and 21 days [14, 21] with stage 3 NEC (Table\u0026nbsp;1).\u003c/p\u003e \u003cp\u003eIn patients with NEC stage 2 or 3, the AMC dropped by an average of 43% of the baseline value at the onset of suspicion (mean rate ratio\u0026thinsp;=\u0026thinsp;0.57 (95% CI 0.41, 0.80), with the lower levels continuing to be observed at follow-up (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. However, this was not observed in the other groups.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe percentage change in AMC from baseline to illness onset significantly differed by diagnosis, p\u0026thinsp;=\u0026thinsp;0.008. Patients with stage 2 and 3 NEC experienced a significant decrease in AMC compared to those with no NEC, stage 1 NEC, or positive blood culture, who demonstrated an increase in AMC (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05; Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eROC curve analysis was used to assess the validity of the percentage change in AMC from baseline to NEC suspicion in order to identify different stages of NEC (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). An increase in AMC of 24% or less can differentiate NEC stage 2 or 3 from stage 1 with an area under the curve (AUC) of 0.78. A decrease in AMC of more than 32% can differentiate stage 2 or 3 vs. stage 1 or no NEC with an AUC of 0.71. There is no statistically significant difference between any NEC and no NEC (AUC 0.57).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eRadiologists reviewed the imaging studies of 93 infants with no NEC or stage 1/2 NEC. A comparison of NEC stages based on imaging only to stages based on comprehensive clinical revision is listed in table 2. There were 14 infants in whom imaging review identified possible stage 2 NEC, whereas their clinical outcomes suggested no NEC. The percentage of AMC change among these infants was compared to that in other infants with confirmed stage 2 NEC, yielding no statistically significant difference. The comparison showed a median change of -33% [IQR: -67, 13] for these infants, as opposed to -47% [IQR: -67, 10] for the latter group, p\u0026thinsp;=\u0026thinsp;0.963.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIt has been previously shown that the percentage change in AMC may correlate with NEC severity (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e). This study similarly demonstrates a decrease in the peripheral AMC in infants with stage 2 and 3 NEC, indicating that this can be an adjunct diagnostic tool. Comparing the AMC at the onset of illness to a prior baseline can increase the suspicion of whether a patient is developing NEC and help guide treatment plans in real-time. Complete blood counts, which include the monocyte count, are frequently obtained from preterm infants admitted to the NICU. Therefore, utilizing delta AMC as an adjunct biomarker is feasible in clinical settings with a quick turnaround time. Other biomarkers investigated for NEC are challenging to obtain in the clinical setting or nonspecific markers of inflammation, which could be elevated for alternative diagnoses such as sepsis (\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan additionalcitationids=\"CR19\" citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThis study aimed to evaluate the AMC as a tool to delineate between no NEC and any NEC to improve diagnostic accuracy and efficiency. However, there was no statistically significant difference in AMC between no NEC and to all stages of NEC. The AMC in infants with stage 1 NEC increased rather than decreased, similar to that observed in infants with sepsis in our cohort. We reason that stage 1 NEC may not show the same decrease in monocyte count because this is a subjective diagnosis without well-defined criteria. Therefore, this group may include patients without intestinal inflammation, which is hypothesized to be the etiology of the lower AMC among infants with NEC. Stage 1 NEC may overlap with culture-negative sepsis in which body fluid cultures testing is negative, but there are other laboratory or clinical findings concerning for infection (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e). The lack of change in AMC for stage 1 NEC may support the hypothesis by Gregory et al. and others that stage 1 NEC could be a pre-NEC condition and, therefore, would not experience a drop in AMC seen in proven NEC stage 2\u0026ndash;3 (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e). Our findings do not allow for a complete delineation of this hypothesis; however, further studies are required.\u003c/p\u003e \u003cp\u003eThis study has several limitations. As this was a retrospective review, variations were observed in the timing of the CBCs obtained. This study also does not consider aspects of care in the NICU. However, this was a single-institution study with a relatively uniform standard of care, as most of these infants were cared for in our extremely low birthweight infants\u0026rsquo; program (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e). Finally, a few patients underwent multiple NEC evaluations. However, only their first evaluations were included, and there was no statistical difference if the groups were broken down by subjects or by NEC evaluation episodes.\u003c/p\u003e \u003cp\u003eOur study has several strengths. NEC staging was not based on a pre-existing database. However, the three neonatologist investigators reviewed the patients' records in detail a with consensus to determine the clinical outcome. Analysis of AMC also included patients who might have overlapping diagnoses such as SIP or sepsis to help better understand the role of AMC in differentiating between NEC and other conditions. In addition, blinded verification of NEC staging by two separate radiologists was performed.\u003c/p\u003e \u003cp\u003eThe results of our study reinforce that NEC remains a challenging diagnosis with a high risk of diagnostic error. Often defined as a missed opportunity to establish a timely, accurate diagnosis (\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e), diagnostic errors are expected when considering intra-abdominal pathology, such as NEC (\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e). However, the increasing availability of diagnostic testing in the NICU can lead to over-testing and over-diagnosis of NEC (\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e). This is complicated by the fact that the diagnostic process in the NICU, similar to other dynamic rapid-pace settings, is non-linear. Critically ill neonates may present with active deterioration, which requires prioritizing stabilization over a formal diagnostic evaluation. This highlights the need for continued study of potential biomarkers with high diagnostic accuracy and rapid turnaround time when clinicians suspect a patient is developing NEC.\u003c/p\u003e \u003cp\u003eOur data also suggest that stage 1 NEC remains an elusive entity to define; however the heavy burden of overtreatment versus the risks of missed cases that may progress reinforces the need for additional diagnostic tools. Thus, future studies to better describe stage 1 NEC would help identify those with alternative etiologies, target treatment length, and improve antibiotic stewardship (\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e). Notably, 40 out of 50 (80%) infants with no NEC were suspected to have stage 1 or stage 2 NEC based on imaging studies only. This suggests the need for continued refinement of the radiological approach for diagnosing NEC. Recent improvements in ultrasound technology as a modality for NEC diagnosis are exciting (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e), as pathognomonic radiological findings such as pneumatosis intestinalis were visualized more accurately with ultrasound than with X-rays (\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e). Future directions toward utilizing machine learning and artificial intelligence might augment the clinical capabilities for accurate and timely diagnosis of necrotizing enterocolitis(\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e).\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eA decrease in the AMC over time can be used as an adjunctive biomarker to identify NEC stage 2 and 3, when compared to no NEC or stage 1 NEC. However, AMC values cannot be used to rule out NEC reliably, and future studies are needed to elucidate a reliable biomarker to rule out the presence of NEC.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eStatement of Ethics\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eStudy approval statement\u003c/u\u003e: The study protocol was reviewed and approved by Children\u0026rsquo;s Hospital of Orange County IRB Committee, IRB ID 1919772-1 internal number 200574. No ethics approval was needed.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cu\u003eConsent to participate statement\u003c/u\u003e: This study was granted by the Children\u0026rsquo;s Hospital of Orange County IRB, an exemption from written informed consent given the retrospective nature of the study.\u003c/p\u003e\n\u003cp\u003eConflict of Interest Statement\u003c/p\u003e\n\u003cp\u003eThe authors have no conflicts of interest to declare.\u003c/p\u003e\n\u003cp\u003eFunding Sources\u003c/p\u003e\n\u003cp\u003eNo funding sources to disclose.\u003c/p\u003e\n\u003cp\u003eAuthor Contributions\u003c/p\u003e\n\u003cp\u003eDrs. Moroze, Shafer, and Mikhael contributed to the conceptualization and design of the study, the collection, analysis, and interpretation of the data. They drafted the initial manuscript and approved the final manuscript as submitted. Mrs. Morphew and Dr. Sayrs contributed to the analysis and interpretation of the data. They contributed to all drafts of the manuscript and approved the final manuscript as submitted. Drs. Eghbal and Holmes contributed to the collection, analysis, and interpretation of the data. They contributed to all drafts of the manuscript and approved the final manuscript as submitted.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eDuchon J, Barbian ME, Denning PW. Necrotizing Enterocolitis. Vol. 48, Clinics in Perinatology. W.B. Saunders; 2021. p. 229\u0026ndash;50.\u003c/li\u003e\n \u003cli\u003eMeinzen-Derr J, Morrow AL, Hornung RW, Donovan EF, Dietrich KN, Succop PA. Epidemiology of necrotizing enterocolitis temporal clustering in two neonatology practices. J Pediatr. 2009 May;154(5):656\u0026ndash;61.\u003c/li\u003e\n \u003cli\u003eNeu J, Walker WA. Necrotizing Enterocolitis. New England Journal of Medicine. 2011 Jan 20;364(3):255\u0026ndash;64.\u003c/li\u003e\n \u003cli\u003eHunter CJ, Upperman JS, Ford HR, Camerini V. Understanding the Susceptibility of the Premature Infant to Necrotizing Enterocolitis (NEC). Vol. 63, Pediatr Res. 2008.\u003c/li\u003e\n \u003cli\u003eZozaya C, Garc\u0026iacute;a Gonz\u0026aacute;lez I, Avila-Alvarez A, Oikonomopoulou N, S\u0026aacute;nchez Tamayo T, Salguero E, et al. Incidence, Treatment, and Outcome Trends of Necrotizing Enterocolitis in Preterm Infants: A Multicenter Cohort Study. Front Pediatr. 2020 May 13;8.\u003c/li\u003e\n \u003cli\u003eBlakely ML, Lally KP, McDonald S, Brown RL, Barnhart DC, Ricketts RR, et al. Postoperative Outcomes of Extremely Low Birth-Weight Infants With Necrotizing Enterocolitis or Isolated Intestinal Perforation. Ann Surg. 2005 Jun;241(6):984\u0026ndash;94.\u003c/li\u003e\n \u003cli\u003eBell EF, Hintz SR, Hansen NI, Bann CM, Wyckoff MH, DeMauro SB, et al. Mortality, In-Hospital Morbidity, Care Practices, and 2-Year Outcomes for Extremely Preterm Infants in the US, 2013-2018. JAMA. 2022 Jan 18;327(3):248.\u003c/li\u003e\n \u003cli\u003eHackam D, Caplan M. Necrotizing enterocolitis: Pathophysiology from a historical context. Semin Pediatr Surg. 2018 Feb 1;27(1):11\u0026ndash;8.\u003c/li\u003e\n \u003cli\u003eBELL MJ, TERNBERG JL, FEIGIN RD, KEATING JP, MARSHALL R, BARTON L, et al. Neonatal Necrotizing Enterocolitis. Ann Surg. 1978 Jan;187(1):1\u0026ndash;7.\u003c/li\u003e\n \u003cli\u003eShah J, Singhal N, da Silva O, Rouvinez-Bouali N, Seshia M, Lee SK, et al. Intestinal perforation in very preterm neonates: risk factors and outcomes. Journal of Perinatology. 2015 Aug 30;35(8):595\u0026ndash;600.\u003c/li\u003e\n \u003cli\u003eGoldstein GP, Sylvester KG. Biomarker Discovery and Utility in Necrotizing Enterocolitis. Clin Perinatol. 2019 Mar;46(1):1\u0026ndash;17.\u003c/li\u003e\n \u003cli\u003eAlganabi M, Lee C, Bindi E, Li B, Pierro A. Recent advances in understanding necrotizing enterocolitis [version 1; referees: 2 approved]. Vol. 8, F1000Research. F1000 Research Ltd; 2019.\u003c/li\u003e\n \u003cli\u003eMohanKumar K, Namachivayam K, Ho TTB, Torres BA, Ohls RK, Maheshwari A. Cytokines and growth factors in the developing intestine and during necrotizing enterocolitis. Semin Perinatol. 2017 Feb;41(1):52\u0026ndash;60.\u003c/li\u003e\n \u003cli\u003eDesiraju S, Bensadoun J, Bateman D, Kashyap S. The role of absolute monocyte counts in predicting severity of necrotizing enterocolitis. Journal of Perinatology. 2020 Jun 1;40(6):922\u0026ndash;7.\u003c/li\u003e\n \u003cli\u003eMaheshwari A. Immunologic and Hematological Abnormalities in Necrotizing Enterocolitis. Clin Perinatol. 2015 Sep;42(3):567\u0026ndash;85.\u003c/li\u003e\n \u003cli\u003eRemon J, Kampanatkosol R, Kaul RR, Muraskas JK, Christensen RD, Maheshwari A. Acute drop in blood monocyte count differentiates NEC from other causes of feeding intolerance. Journal of Perinatology. 2014 Jul 27;34(7):549\u0026ndash;54.\u003c/li\u003e\n \u003cli\u003eWang Z, Chong Q, Zhou J, Gao T, Zhu K, Gong X, et al. Reduction of absolute monocyte counts is associated with the severity of preterm necrotizing enterocolitis. J Pediatr (Rio J). 2023 Apr;\u003c/li\u003e\n \u003cli\u003eEdelson MB, Sonnino RE, Bagwell CE, Lieberman JM, Marks WH, Rozycki HJ. Plasma intestinal fatty acid binding protein in neonates with necrotizing entercolitis: A pilot study. J Pediatr Surg. 1999 Oct;34(10):1453\u0026ndash;7.\u003c/li\u003e\n \u003cli\u003eLobe TE, Richardson CJ, Rassin DK, Mills R, Schwartz M. Hexosaminidase: A biochemical marker for necrotizlng enterocolitls in the preterm infant. The American Journal of Surgery. 1984 Jan;147(1):49\u0026ndash;52.\u003c/li\u003e\n \u003cli\u003eAgakidou E, Agakidis C, Gika H, Sarafidis K. Emerging Biomarkers for Prediction and Early Diagnosis of Necrotizing Enterocolitis in the Era of Metabolomics and Proteomics. Vol. 8, Frontiers in Pediatrics. Frontiers Media S.A.; 2020.\u003c/li\u003e\n \u003cli\u003eCantey JB, Prusakov P. A Proposed Framework for the Clinical Management of Neonatal \u0026ldquo;Culture-Negative\u0026rdquo; Sepsis. Vol. 244, Journal of Pediatrics. Elsevier Inc.; 2022. p. 203\u0026ndash;11.\u003c/li\u003e\n \u003cli\u003eGregory KE, DeForge CE, Natale KM, Phillips M, Van Marter LJ. Necrotizing enterocolitis in the premature infant: Neonatal nursing assessment, disease pathogenesis, and clinical presentation. Advances in Neonatal Care. 2011 Jun;11(3):155\u0026ndash;64.\u003c/li\u003e\n \u003cli\u003eMorris M, Cleary JP, Soliman A. Small Baby Unit Improves Quality and Outcomes in Extremely Low Birth Weight Infants. Pediatrics. 2015 Oct 1;136(4):e1007\u0026ndash;15.\u003c/li\u003e\n \u003cli\u003eSingh H. Editorial: Helping health care organizations to define diagnostic errors as missed opportunities in diagnosis. Jt Comm J Qual Patient Saf. 2014 Mar;40(3):99\u0026ndash;101.\u003c/li\u003e\n \u003cli\u003eShafer GJ, Singh H, Thomas EJ, Thammasitboon S, Gautham KS. Frequency of diagnostic errors in the neonatal intensive care unit: a retrospective cohort study. J Perinatol. 2022 Oct;42(10):1312\u0026ndash;8.\u003c/li\u003e\n \u003cli\u003eWelch HG. Responding to the challenge of overdiagnosis. Acad Radiol. 2015 Aug;22(8):945\u0026ndash;6.\u003c/li\u003e\n \u003cli\u003eShah D, Sinn JKH. Antibiotic regimens for the empirical treatment of newborn infants with necrotising enterocolitis. Cochrane Database Syst Rev. 2012 Aug 15;(8):CD007448.\u003c/li\u003e\n \u003cli\u003eBull KE, Gainey AB, Cox CL, Burch AK, Durkin M, Daniels R. Evaluation of Time to Resolution of Medical Necrotizing Enterocolitis Using Severity-Guided Management in a Neonatal Intensive Care Unit. J Pediatr Pharmacol Ther. 2021;26(2):179\u0026ndash;86.\u003c/li\u003e\n \u003cli\u003eChen S, Hu Y, Liu Q, Li X, Wang H, Wang K, et al. Application of abdominal sonography in diagnosis of infants with necrotizing enterocolitis. Medicine. 2019 Jul;98(28):e16202.\u003c/li\u003e\n \u003cli\u003eMuchantef K, Epelman M, Darge K, Kirpalani H, Laje P, Anupindi SA. Sonographic and radiographic imaging features of the neonate with necrotizing enterocolitis: correlating findings with outcomes. Pediatr Radiol. 2013 Nov 15;43(11):1444\u0026ndash;52.\u003c/li\u003e\n \u003cli\u003eBłaż W. Usefulness of Ultrasound Examinations in the Diagnostics of Necrotizing Enterocolitis. Pol J Radiol. 2014;79:1\u0026ndash;9.\u003c/li\u003e\n \u003cli\u003eSitek A, Seliga-Siwecka J, Płotka S, Grzeszczyk MK, Seliga S, Włodarczyk K, et al. Artificial intelligence in the diagnosis of necrotising enterocolitis in newborns. Pediatr Res. 2023 Jan;93(2):376\u0026ndash;81.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTables 1-2 are available in the Supplementary Files section\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-perinatology","isNatureJournal":false,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"jp","sideBox":"Learn more about [Journal of Perinatology](http://www.nature.com/jp/)","snPcode":"41372","submissionUrl":"https://mts-jper.nature.com/cgi-bin/main.plex","title":"Journal of Perinatology","twitterHandle":"@jperinatology","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Absolute Monocyte Count, Necrotizing Enterocolitis, Pneumatosis Intestinalis","lastPublishedDoi":"10.21203/rs.3.rs-3722321/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3722321/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe investigated the trends of blood absolute monocyte count (AMC) over 72 hours after suspecting necrotizing enterocolitis (NEC).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStudy Design\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA single center, retrospective study, the AMC was plotted over 72 hours after NEC evaluation. Receiver operating characteristic (ROC) curve analysis assessed change in AMC to identify absence of NEC and different NEC stages.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn 130 infants, the AMC decreased in patients with NEC stage 2 or 3. \u0026nbsp;Stages 2 and 3 NEC experienced a drop in AMC compared to an increase in no NEC, Stage 1, or positive culture (p\u0026lt;0.05). AMC increase 24% or less can differentiate NEC stage 2/3 from stage 1 with an area under the curve (AUC) of 0.78. There wasn’t statistical difference between any NEC and no NEC (AUC, 0.57).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDiscussion/Conclusions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA decrease in AMC can be an adjunct biomarker to identify NEC stage 2 and 3, when compared to no NEC/stage 1.\u003c/p\u003e","manuscriptTitle":"Blood Absolute Monocyte Count Trends in Preterm Infant with Suspected Necrotizing Enterocolitis, an Adjunct Tool for Diagnosis?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-01-02 19:54:02","doi":"10.21203/rs.3.rs-3722321/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"revise","date":"2024-02-05T16:03:26+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"This content is not available.","date":"2024-01-25T13:52:13+00:00","index":2,"fulltext":"This content is not available."},{"type":"reviewerAgreed","content":"This content is not available.","date":"2024-01-18T18:24:56+00:00","index":2,"fulltext":"This content is not available."},{"type":"editorInvitedReview","content":"This content is not available.","date":"2024-01-12T22:58:23+00:00","index":1,"fulltext":"This content is not available."},{"type":"reviewerAgreed","content":"This content is not available.","date":"2023-12-31T16:03:46+00:00","index":1,"fulltext":"This content is not available."},{"type":"reviewersInvited","content":"","date":"2023-12-27T03:23:57+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2023-12-08T12:31:14+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Perinatology","date":"2023-12-07T20:40:08+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2023-12-07T20:40:08+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-perinatology","isNatureJournal":false,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"jp","sideBox":"Learn more about [Journal of Perinatology](http://www.nature.com/jp/)","snPcode":"41372","submissionUrl":"https://mts-jper.nature.com/cgi-bin/main.plex","title":"Journal of Perinatology","twitterHandle":"@jperinatology","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"5cb4a00f-042f-422f-b986-291282db1802","owner":[],"postedDate":"January 2nd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":27796319,"name":"Health sciences/Health care/Diagnosis/Laboratory techniques and procedures"},{"id":27796320,"name":"Health sciences/Biomarkers/Diagnostic markers"}],"tags":[],"updatedAt":"2024-08-02T07:06:22+00:00","versionOfRecord":{"articleIdentity":"rs-3722321","link":"https://doi.org/10.1038/s41372-024-02070-7","journal":{"identity":"journal-of-perinatology","isVorOnly":false,"title":"Journal of Perinatology"},"publishedOn":"2024-08-01 04:00:00","publishedOnDateReadable":"August 1st, 2024"},"versionCreatedAt":"2024-01-02 19:54:02","video":"","vorDoi":"10.1038/s41372-024-02070-7","vorDoiUrl":"https://doi.org/10.1038/s41372-024-02070-7","workflowStages":[]},"version":"v1","identity":"rs-3722321","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3722321","identity":"rs-3722321","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}