Urinary Neutrophil Gelatinase-Associated Lipocalin Concentration: A Baseline Study for Establishing Reference Ranges in Preterm Neonates

Urinary Neutrophil Gelatinase-Associated Lipocalin Concentration: A Baseline Study for Establishing Reference Ranges in Preterm Neonates | 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 Article Urinary Neutrophil Gelatinase-Associated Lipocalin Concentration: A Baseline Study for Establishing Reference Ranges in Preterm Neonates Nicole Asdell, Jonathan Slaughter, Shivam Joshi, Elizabeth Bonachea, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7179930/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 12 You are reading this latest preprint version Abstract Background: Acute kidney injury (AKI) is common in preterm neonates and is associated with morbidity and mortality. Urinary neutrophil gelatinase-associated lipocalin (uNGAL) is a promising biomarker for early AKI detection, but its clinical utility is hindered by a lack of normative reference ranges in preterm infants. Objective: To characterize baseline uNGAL concentrations during the first postnatal week in preterm neonates without AKI and evaluate associations with gestational age (GA), birth weight (BW), and sex. Methods: Retrospective cohort study of 100 neonates <32 weeks’ gestation without AKI, NEC, sepsis, or UTI. uNGAL and uNGAL/uCr ratios were measured and analyzed by GA, BW, and sex. Results: uNGAL and uNGAL/uCr levels decreased with increasing GA and BW (p<0.001). Females had higher uNGAL levels than males (p=0.007) Conclusions: Baseline uNGAL varies with GA, BW, and sex in preterm neonates. Development of age-specific reference ranges would enhance the diagnostic utility of uNGAL in neonatal AKI. Health sciences/Biomarkers/Predictive markers Biological sciences/Developmental biology Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Acute kidney injury (AKI) is increasingly recognized as a major contributor to morbidity in preterm neonates, with an incidence as high as 48% in babies born less than 27 weeks' gestation. The impact of AKI is profound - studies have associated neonatal AKI with prolonged mechanical ventilation and worse lung outcomes, longer hospital stays, intraventricular hemorrhage (IVH), and increased risk of mortality [ 1 – 3 ] . AKI in infancy has also been linked to later development of chronic kidney disease and hypertension [ 4 – 7 ] . Despite its prevalence and consequences, AKI remains challenging to diagnose in neonates due to limitations of conventional diagnostic tools. Serum creatinine, the most commonly used marker, reflects maternal levels during the first few days of life and fluctuates with muscle mass, fluid status, and renal perfusion, making it unreliable for AKI detection in this population [ 4 – 9 ] . Urine output is an important element of many neonatal AKI definitions, but measuring urine output accurately in preterm infants is challenging. Neutrophil gelatinase-associated lipocalin (NGAL), a 25-kDa protein expressed in neutrophils and renal tubular cells, rises rapidly in the urine following tubular kidney injury and has demonstrated diagnostic value as a urinary biomarker in pediatric and adult patients with AKI [ 4 , 10 – 12 ] . In neonates, particularly those born prematurely, the clinical utility of NGAL remains hindered by the absence of well-defined normative reference ranges. Limited studies have examined urinary NGAL (uNGAL) concentrations in neonates without AKI, and findings suggest that levels are influenced by gestational age, birth weight, and sex [ 4 , 9 , 10 ] . De Mul et al. reported significantly elevated uNGAL in females and in those with renal stressors [ 12 ] , while Mohammed et al. observed a wide range of values in healthy neonates without AKI [ 10 ] . Still, no standardized reference ranges exist, and current data are limited by small sample sizes, inconsistent methodologies, and variable exclusion criteria. To bridge this gap, we conducted a retrospective cohort study of 100 preterm neonates < 32 weeks' gestation without AKI or associated renal insults. Our aim was to describe baseline uNGAL concentrations during the first postnatal week and evaluate their association with gestational age, sex, and birth weight. These findings are intended to inform future efforts to establish clinically meaningful reference intervals for neonatal AKI diagnostics. Methods Study Design and Setting This retrospective cohort study was conducted in the Level IV NICU at Nationwide Children’s Hospital in Columbus, Ohio. The study protocol was approved by the institutional IRB. Informed consent was obtained from the parent or legal guardian of each enrolled neonate. Inclusion and Exclusion Criteria Neonates born < 32 weeks GA between 2010–2020 admitted to the Nationwide Children’s level IV NICU who had urine obtained and stored in the Ohio Perinatal Research Network (OPRN) database within the first week of life were considered for the study. Individualized chart reviews were performed for each subject. Urine NGAL has shown to be elevated in response to systemic inflammation and infection, so infants who had AKI, urinary tract infection (UTI), necrotizing enterocolitis (NEC), or sepsis during their initial hospital admission were excluded [ 12 – 13 ] . AKI was identified using the creatinine-only neonatal modified KDIGO criteria. UTI was defined by a positive urine culture that received treatment with antibiotics. NEC was defined as concern for abnormal radiograph findings with pneumatosis or concern for pneumatosis when the infant required NPO status and antibiotic treatment for at least 7 days, or need for surgery. Infants were considered to have sepsis if they received antibiotics for > 48h after birth, if sepsis was recorded on the diagnostic problem list in the medical record, or if they had a positive blood culture. Sample Collection and Processing Urine samples were collected using sterile cotton balls placed in the diaper and transferred via syringe into cryotubes, then stored at -80C in the Ohio Perinatal Research Biorepository. All samples were obtained during the first 7 days of life. Laboratory Analysis Urinary NGAL (uNGAL) concentrations were quantified via particle-enhanced immunoturbidimetry using BioPorto Diagnostics reagents and a Roche Cobas analyzer. Urinary creatinine (uCr) was measured enzymatically. Data Collection and Stratification Demographic data, including sex, gestational age (GA), and birth weight were abstracted from the electronic medical record. Participants were grouped into GA categories: 23–25, 26–28, and 29–31 weeks. uNGAL and the uNGAL/uCr ratio were compared across these strata. Individualized chart reviews were conducted to capture other key clinical variables. Statistical Analysis The Chi-squared test was used to examine the association between categorical variables and GA groups, while the Kruskal-Wallis rank sum test and ANOVA were used to identify differences in the distribution of continuous variables across GA groups. Pearson’s correlation assessed the relationship between GA and uNGAL and GA and the uNGAL/uCr ratio. Statistical significance was determined at an alpha level of 0.05. Results A total of 100 neonates were included. The median gestational age was 27.3 weeks and the median birth weight was 950g. Forty-eight percent of the subjects were female. The median urine NGALs for infants born 23–25, 26–28, and 29–31 weeks were 653, 205, and 78 ng/dL respectively. Similarly, the uNGAL/uCr ratios at these GA were 62,19, and 7.9 ng/dL respectively. Baseline urinary concentrations of both uNGAL (R=-0.606, p < 0.001) and uNGAL/uCr (R=-0503, p = < 0.0001) decreased significantly as GA increased (Fig. 1). Baseline concentrations of uNGAL (R=-0.483, p = < 0.0001) and uNGAL/uCr ratio (R= -0.567, p < 0.0001) decreased with increasing birth weight (Fig. 3, Fig. 4). Females had significantly higher uNGAL levels compared to males (mean 225 vs 165ng/mL; p = 0.007). Discussion This study provides foundational data on baseline uNGAL concentrations in preterm neonates by different gestational ages during the first week of life. Our results affirm the strong influence of gestational age, birth weight, and sex on uNGAL levels, and underscore the importance of establishing age-specific reference intervals to improve the utility of uNGAL in AKI diagnosis and risk stratification in this population. We observed an inverse relationship between gestational age and both raw and normalized uNGAL concentrations, consistent with previous smaller studies. The higher values in earlier gestational ages likely reflect either immature tubular function and increased permeability of the glomerular barrier and/or physiologically higher levels of NGAL during tubular maturation. These findings validate the need to interpret uNGAL values within the context of developmental maturity. Sex-based differences in uNGAL have been previously reported and were confirmed here. Possible explanations include sex-based differences in tubular enzyme expression, hormonal effects, and differences in urinary white blood cell (WBC) excretion and the potential for subclinical or asymptomatic leukocyturia, which is more prevalent in females [ 16 – 18 ] . The use of the unGAL/uCr ratio to normalize urine concentration variability adds robustness to our findings. This approach is particularly relevant in preterm infants, where fluid status and urine output may fluctuate widely and affect baseline biomarker concentration. Study strengths include a robust number of ELGANs. Detailed personalized chart reviews were conducted on each subject to search for comorbidities so that infants could be excluded as appropriate. Our study is limited by its single-center design and reliance on spot urine samples rather than timed collections. We also excluded infants with AKI, NEC, sepsis, and PDA treatment, which, while necessary for establishing normative data, limits generalizability to all ELGAN populations. Conclusion Baseline urinary neutrophil gelatinase-associated lipocalin (uNGAL) levels were shown to be elevated in preterm neonates. NGAL is detectable in the urine as early as 23 weeks gestation and its’ concentration decreases with increasing gestational age. Additionally, baseline uNGAL levels decrease with increasing birth weight and are higher in female neonates compared to male neonates. These findings underscore the variability of uNGAL levels based on gestational age, birth weight, and sex, highlighting the need for further studies to establish precise reference intervals for uNGAL in preterm neonates. Establishing these reference intervals is crucial for improving the diagnostic utility of uNGAL as a non-invasive and blood-sparing biomarker for early detection of AKI in this vulnerable population. Early detection of AKI using uNGAL could potentially lead to timely interventions and better clinical outcomes, as it allows for the identification of kidney injury before changes in urine output or serum creatinine levels become apparent. Future research should focus on larger cohorts and diverse populations to validate these findings and refine the use of uNGAL in clinical practice. Declarations The authors have no financial conflicts of interest to disclose. This study was approved by the IRB at Nationwide Children’s Hospital. The study was performed in accordance with the Declaration of Helsinki. Drs. Nicole Asdell and Tahagod Mohamed conceptualized and designed the study. Dr. Nicole Asdell performed chart review and drafted the original paper. Shivam Joshi analyzed data and created figures. All authors contributed to manuscript writing and editing and approved the final draft. References Jetton JG, Boohaker LJ, Sethi SK, et al. Incidence and outcomes of neonatal acute kidney injury (AWAKEN): a multicentre, multinational, observational cohort study. Lancet Child Adolesc Health . 2017;1(3):184–194. doi: 10.1016/S2352-4642(17)30069-X . Starr MC, Boohaker L, Eldredge LC, et al. Acute Kidney Injury is Associated with Poor Lung Outcomes in Infants Born ≥ 32 Weeks of Gestational Age. Am J Perinatol. 2020;37(2):231–240. doi: 10.1055/s-0039-1698836 Coleman C, Tambay Perez A, Selewski DT, Steflik HJ. Neonatal Acute Kidney Injury. Front Pediatr. 2022;10:842544. doi: 10.3389/fped.2022.842544 . PMID: 35463895; PMCID: PMC9021424. Panza R, Schirinzi A, Baldassarre ME, et al. Evaluation of uNGAL and TIMP-2*IGFBP7 as early biomarkers of Acute Kidney Injury in Caucasian term and preterm neonates: a prospective observational cohort study. Ital J Pediatr . 2025;51(1):64. doi: 10.1186/s13052-025-01899-8 . Askenazi DJ, Heagerty PJ, Schmicker RH, et al. Prevalence of acute kidney injury (AKI) in extremely low gestational age neonates (ELGAN). Pediatr Nephrol . 2020;35(9):1737–1748. doi: 10.1007/s00467-020-04599-5 . Filler, G., et al., How should we assess renal function in neonates and infants? Acta Paediatr, 2021. 110(3): p. 773–780. Ameta P, Stoops C, Askenazi DJ. Risk of chronic kidney disease in children who developed acute kidney injury secondary to nephrotoxic medication exposure in infancy. Ren Fail. 2023;45(1):2218486. doi: 10.1080/0886022X.2023.2218486. PMID: 37254865; PMCID: PMC10234137. Chaturvedi S, Ng KH, Mammen C. The path to chronic kidney disease following acute kidney injury: a neonatal perspective. Pediatr Nephrol. 2017;32(2):227–241. doi: 10.1007/s00467-015-3298-9 . Epub 2016 Jan 25. PMID: 26809804. Harer MW, Pope CF, Conaway MR, Charlton JR. Follow-up of Acute kidney injury in Neonates during Childhood Years (FANCY): a prospective cohort study. Pediatr Nephrol. 2017;32(6):1067–1076. doi: 10.1007/s00467-017-3603-x . Epub 2017 Mar 3. PMID: 28255805. Miall, L.S., et al., Plasma creatinine rises dramatically in the first 48 hours of life in preterm infants. Pediatrics, 1999. 104(6): p. e76. Lavery AP, Meinzen-Derr J, Anderson E, et al. Urinary NGAL in premature infants. Pediatr Res . 2008;64(4):423–428. doi: 10.1203/PDR.0b013e318181b4c1 Mohamed D, et al. Urinary Neutrophil Gelatinase-Associated Lipocalin Values in Preterm Neonates: A Systematic Review and Meta-analysis. Am J Perinatol . 2024;41(3):e1-e9. doi: 10.1055/a-2417-4087 . Lu Y, Fan Y, et al. Urinary NGAL and KIM-1 Are the Early Detecting Biomarkers of Preterm Infants with Acute Kidney Injury. J Neonatal Perinatal Med . 2023;16(2):123–130. doi: 10.3233/NPM-220015 . De Mul N, et al. Reference Values of Urinary Neutrophil Gelatinase-Associated Lipocalin in Very Low Birth Weight Infants. Pediatr Res . 2009;66(4):433–437. doi: 10.1203/PDR.0b013e3181b3b9e7 . Chen JJ, Lee TH, Lee CC, Chang CH. Using lipocalin as a prognostic biomarker in acute kidney injury. Expert Rev Mol Diagn. 2021;21(5):455–464. doi: 10.1080/14737159.2021.1917384. Epub 2021 Apr 19. PMID: 33874823. Marakala V. Neutrophil gelatinase-associated lipocalin (NGAL) in kidney injury - A systematic review. Clin Chim Acta. 2022;536:135–141. doi: 10.1016/j.cca.2022.08.029 . Epub 2022 Sep 21. PMID: 36150522. Cullen MR, Murray PT, Fitzgibbon MC. Establishment of a reference interval for urinary neutrophil gelatinase-associated lipocalin. Ann Clin Biochem. 2012;49(Pt 2):190–3. doi: 10.1258/acb.2011.011105 . Epub 2012 Feb 9. PMID: 22323662. Decavele AS, Dhondt L, De Buyzere ML, Delanghe JR. Increased urinary neutrophil gelatinase associated lipocalin in urinary tract infections and leukocyturia. Clin Chem Lab Med. 2011;49(6):999–1003. doi: 10.1515/CCLM.2011.156. Epub 2011 Mar 11. PMID: 21391867. Morita Y, Kurano M, Tanaka M, Hisasue T, Sato M, Ono Y, Sato T, Shukuya K, Yatomi Y. Midstream urine sampling is necessary for accurate measurement of the urinary level of neutrophil gelatinase-associated lipocalin in healthy female subjects. Clin Biochem. 2020;79:70–74. doi: 10.1016/j.clinbiochem.2020.03.005. Epub 2020 Mar 14. PMID: 32184106. Additional Declarations There is NO conflict of interest to disclose. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: revise 15 Oct, 2025 Review # 3 received at journal 02 Oct, 2025 Review # 2 received at journal 01 Oct, 2025 Reviewer # 3 agreed at journal 30 Sep, 2025 Review # 1 received at journal 26 Aug, 2025 Reviewer # 2 agreed at journal 23 Aug, 2025 Reviewer # 1 agreed at journal 19 Aug, 2025 Reviewers invited by journal 04 Aug, 2025 Submission checks completed at journal 24 Jul, 2025 First submitted to journal 23 Jul, 2025 Unknown event 22 Jul, 2025 Editor assigned by journal 21 Jul, 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-7179930","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":495720174,"identity":"6d6841a6-1244-40a3-b067-21a551542601","order_by":0,"name":"Nicole Asdell","email":"data:image/png;base64,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","orcid":"https://orcid.org/0009-0001-9289-9580","institution":"Natiownide Children's Hospital","correspondingAuthor":true,"prefix":"","firstName":"Nicole","middleName":"","lastName":"Asdell","suffix":""},{"id":495720175,"identity":"051cbefa-d3e9-4288-b123-3077749b7182","order_by":1,"name":"Jonathan Slaughter","email":"","orcid":"https://orcid.org/0000-0001-6831-7520","institution":"The Ohio State University","correspondingAuthor":false,"prefix":"","firstName":"Jonathan","middleName":"","lastName":"Slaughter","suffix":""},{"id":495720176,"identity":"0284c871-5bb5-403f-b7ca-ba991b6b48f1","order_by":2,"name":"Shivam Joshi","email":"","orcid":"https://orcid.org/0009-0000-9164-4036","institution":"Ohio State University","correspondingAuthor":false,"prefix":"","firstName":"Shivam","middleName":"","lastName":"Joshi","suffix":""},{"id":495720177,"identity":"d5855c42-6e9a-4f1c-8b86-dddacafb1cb9","order_by":3,"name":"Elizabeth Bonachea","email":"","orcid":"","institution":"Nationwide Children's Hospital and The Ohio State University","correspondingAuthor":false,"prefix":"","firstName":"Elizabeth","middleName":"","lastName":"Bonachea","suffix":""},{"id":495720178,"identity":"0e77f0a3-d4ad-47d5-a9f6-0e8433a9a06b","order_by":4,"name":"Tahagod Mohamed","email":"","orcid":"https://orcid.org/0000-0002-6010-0711","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Tahagod","middleName":"","lastName":"Mohamed","suffix":""}],"badges":[],"createdAt":"2025-07-21 17:35:21","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7179930/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7179930/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":88645515,"identity":"43209acf-8172-4f1f-989c-0dfd353b7caa","added_by":"auto","created_at":"2025-08-08 16:26:01","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":95203,"visible":true,"origin":"","legend":"\u003cp\u003eu\u003cstrong\u003eNGAL by Gestational Age Group in Preterm Infants\u003c/strong\u003e\u003cbr\u003e\n Median uNGAL concentrations (ng/mL) in preterm neonates stratified by gestational age: 23–25 weeks (n=29), 26–28 weeks (n=38), and 29–31 weeks (n=33). uNGAL levels declined significantly with increasing gestational age (\u003cem\u003ep\u003c/em\u003e\u0026lt;0.001).\u003c/p\u003e","description":"","filename":"Picture1.png","url":"https://assets-eu.researchsquare.com/files/rs-7179930/v1/735f9c030612e0d1f79b93cc.png"},{"id":88645517,"identity":"283c4df3-9976-4f4c-b0cb-98642a0c7adc","added_by":"auto","created_at":"2025-08-08 16:26:02","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":131848,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003euNGAL/uCr Ratio by Gestational Age \u003c/strong\u003e\u003cbr\u003e\n Box-and-whisker plot showing urinary neutrophil gelatinase-associated lipocalin (uNGAL) normalized to urinary creatinine (uNGAL/uCr, ng/mg) across gestational age groups: 23–25 weeks, 26–28 weeks, and 29–31 weeks. Median values declined significantly with increasing gestational age (\u003cem\u003ep\u003c/em\u003e\u0026lt;0.001).\u003c/p\u003e","description":"","filename":"Picture2.png","url":"https://assets-eu.researchsquare.com/files/rs-7179930/v1/04da73e05b035b7fc3194081.png"},{"id":88645514,"identity":"8e13dcdd-49dc-42d1-8016-4ae0908f33fc","added_by":"auto","created_at":"2025-08-08 16:26:01","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":86224,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eBirth Weight and Log-Transformed uNGAL \u003c/strong\u003e\u003cbr\u003e\n Scatter plot showing the relationship between birth weight (g) and log-transformed urinary NGAL concentration (ng/mL). A significant inverse correlation was observed (R = −0.483, \u003cem\u003ep\u003c/em\u003e \u0026lt; 0.0001).\u003c/p\u003e","description":"","filename":"Picture3.png","url":"https://assets-eu.researchsquare.com/files/rs-7179930/v1/68199cd60be4b1fdc9896c4c.png"},{"id":88643860,"identity":"b44884f7-5782-4cb6-ba13-a4bb15f31d87","added_by":"auto","created_at":"2025-08-08 16:18:01","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":92047,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eBirth Weight and Log-Transformed uNGAL/uCr Ratio \u003c/strong\u003e\u003cbr\u003e\n \u0026nbsp;Scatter plot showing the relationship between birth weight (g) and the log-transformed urinary NGAL-to-creatinine ratio (uNGAL/uCr). A significant inverse correlation was observed (R = −0.567, \u003cem\u003ep\u003c/em\u003e\u0026lt; 0.0001).\u003c/p\u003e","description":"","filename":"Picture4.png","url":"https://assets-eu.researchsquare.com/files/rs-7179930/v1/efd3a2e367aa715895c9f8c1.png"},{"id":88643858,"identity":"06207fef-5d8d-441e-bd30-87a724369b02","added_by":"auto","created_at":"2025-08-08 16:18:01","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":21959,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSex-Based Differences in Urinary NGAL Concentrations \u003c/strong\u003e\u003cbr\u003e\n Box-and-whisker plot showing urinary NGAL concentrations (ng/mL) in male (M) and female (F) preterm neonates. Female infants exhibited significantly higher uNGAL levels compared to males (\u003cem\u003ep\u003c/em\u003e = 0.007).\u003c/p\u003e","description":"","filename":"Picture5.png","url":"https://assets-eu.researchsquare.com/files/rs-7179930/v1/cc76fbf6231f2206cfdbb4ee.png"},{"id":88643861,"identity":"79aab5a4-ecbe-4716-b21b-55879c4c2256","added_by":"auto","created_at":"2025-08-08 16:18:01","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":21604,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eSex-Based Differences in uNGAL/uCr Ratio \u003c/strong\u003e\u003cbr\u003e\nBox-and-whisker plot comparing urinary NGAL-to-creatinine ratios (uNGAL/uCr, ng/mg) between male (M) and female (F) preterm neonates. Female infants exhibited significantly higher normalized uNGAL concentrations than males (\u003cem\u003ep\u003c/em\u003e = 0.01).\u003c/p\u003e","description":"","filename":"Picture6.png","url":"https://assets-eu.researchsquare.com/files/rs-7179930/v1/bde51d995ea868d9c40642f9.png"},{"id":88646233,"identity":"d42e8243-3a12-4222-b9f1-b1e38da4b27e","added_by":"auto","created_at":"2025-08-08 16:34:06","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":817905,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7179930/v1/b5c98aa1-0a5d-4a59-bd3d-ec57a83674d6.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e conflict of interest to disclose.","formattedTitle":"Urinary Neutrophil Gelatinase-Associated Lipocalin Concentration: A Baseline Study for Establishing Reference Ranges in Preterm Neonates","fulltext":[{"header":"Introduction","content":"\u003cp\u003eAcute kidney injury (AKI) is increasingly recognized as a major contributor to morbidity in preterm neonates, with an incidence as high as 48% in babies born less than 27 weeks' gestation. The impact of AKI is profound - studies have associated neonatal AKI with prolonged mechanical ventilation and worse lung outcomes, longer hospital stays, intraventricular hemorrhage (IVH), and increased risk of mortality \u003csup\u003e[\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e–\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e. AKI in infancy has also been linked to later development of chronic kidney disease and hypertension \u003csup\u003e[\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e–\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eDespite its prevalence and consequences, AKI remains challenging to diagnose in neonates due to limitations of conventional diagnostic tools. Serum creatinine, the most commonly used marker, reflects maternal levels during the first few days of life and fluctuates with muscle mass, fluid status, and renal perfusion, making it unreliable for AKI detection in this population \u003csup\u003e[\u003cspan additionalcitationids=\"CR5 CR6 CR7 CR8\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e–\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/sup\u003e. Urine output is an important element of many neonatal AKI definitions, but measuring urine output accurately in preterm infants is challenging.\u003c/p\u003e\u003cp\u003eNeutrophil gelatinase-associated lipocalin (NGAL), a 25-kDa protein expressed in neutrophils and renal tubular cells, rises rapidly in the urine following tubular kidney injury and has demonstrated diagnostic value as a urinary biomarker in pediatric and adult patients with AKI \u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e–\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e. In neonates, particularly those born prematurely, the clinical utility of NGAL remains hindered by the absence of well-defined normative reference ranges.\u003c/p\u003e\u003cp\u003eLimited studies have examined urinary NGAL (uNGAL) concentrations in neonates without AKI, and findings suggest that levels are influenced by gestational age, birth weight, and sex [\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e. De Mul et al. reported significantly elevated uNGAL in females and in those with renal stressors \u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e, while Mohammed et al. observed a wide range of values in healthy neonates without AKI \u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e. Still, no standardized reference ranges exist, and current data are limited by small sample sizes, inconsistent methodologies, and variable exclusion criteria.\u003c/p\u003e\u003cp\u003eTo bridge this gap, we conducted a retrospective cohort study of 100 preterm neonates \u0026lt; 32 weeks' gestation without AKI or associated renal insults. Our aim was to describe baseline uNGAL concentrations during the first postnatal week and evaluate their association with gestational age, sex, and birth weight. These findings are intended to inform future efforts to establish clinically meaningful reference intervals for neonatal AKI diagnostics.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cem\u003eStudy Design and Setting\u003c/em\u003e\u003c/p\u003e\u003cp\u003eThis retrospective cohort study was conducted in the Level IV NICU at Nationwide Children’s Hospital in Columbus, Ohio. The study protocol was approved by the institutional IRB. Informed consent was obtained from the parent or legal guardian of each enrolled neonate.\u003c/p\u003e\u003cp\u003e\u003cem\u003eInclusion and Exclusion Criteria\u003c/em\u003e\u003c/p\u003e\u003cp\u003eNeonates born \u0026lt; 32 weeks GA between 2010–2020 admitted to the Nationwide Children’s level IV NICU who had urine obtained and stored in the Ohio Perinatal Research Network (OPRN) database within the first week of life were considered for the study. Individualized chart reviews were performed for each subject. Urine NGAL has shown to be elevated in response to systemic inflammation and infection, so infants who had AKI, urinary tract infection (UTI), necrotizing enterocolitis (NEC), or sepsis during their initial hospital admission were excluded \u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e–\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. AKI was identified using the creatinine-only neonatal modified KDIGO criteria. UTI was defined by a positive urine culture that received treatment with antibiotics. NEC was defined as concern for abnormal radiograph findings with pneumatosis or concern for pneumatosis when the infant required NPO status and antibiotic treatment for at least 7 days, or need for surgery. Infants were considered to have sepsis if they received antibiotics for \u0026gt; 48h after birth, if sepsis was recorded on the diagnostic problem list in the medical record, or if they had a positive blood culture.\u003c/p\u003e\u003cp\u003e\u003cem\u003eSample Collection and Processing\u003c/em\u003e\u003c/p\u003e\u003cp\u003eUrine samples were collected using sterile cotton balls placed in the diaper and transferred via syringe into cryotubes, then stored at -80C in the Ohio Perinatal Research Biorepository. All samples were obtained during the first 7 days of life.\u003c/p\u003e\u003cp\u003e\u003cem\u003eLaboratory Analysis\u003c/em\u003e\u003c/p\u003e\u003cp\u003eUrinary NGAL (uNGAL) concentrations were quantified via particle-enhanced immunoturbidimetry using BioPorto Diagnostics reagents and a Roche Cobas analyzer. Urinary creatinine (uCr) was measured enzymatically.\u003c/p\u003e\u003cp\u003e\u003cem\u003eData Collection and Stratification\u003c/em\u003e\u003c/p\u003e\u003cp\u003eDemographic data, including sex, gestational age (GA), and birth weight were abstracted from the electronic medical record. Participants were grouped into GA categories: 23–25, 26–28, and 29–31 weeks. uNGAL and the uNGAL/uCr ratio were compared across these strata. Individualized chart reviews were conducted to capture other key clinical variables.\u003c/p\u003e\u003ch2\u003eStatistical Analysis\u003c/h2\u003e\u003cp\u003eThe Chi-squared test was used to examine the association between categorical variables and GA groups, while the Kruskal-Wallis rank sum test and ANOVA were used to identify differences in the distribution of continuous variables across GA groups. Pearson’s correlation assessed the relationship between GA and uNGAL and GA and the uNGAL/uCr ratio. Statistical significance was determined at an alpha level of 0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 100 neonates were included. The median gestational age was 27.3 weeks and the median birth weight was 950g. Forty-eight percent of the subjects were female. The median urine NGALs for infants born 23\u0026ndash;25, 26\u0026ndash;28, and 29\u0026ndash;31 weeks were 653, 205, and 78 ng/dL respectively. Similarly, the uNGAL/uCr ratios at these GA were 62,19, and 7.9 ng/dL respectively. Baseline urinary concentrations of both uNGAL (R=-0.606, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and uNGAL/uCr (R=-0503, p\u0026thinsp;=\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) decreased significantly as GA increased (Fig.\u0026nbsp;1). Baseline concentrations of uNGAL (R=-0.483, p\u0026thinsp;=\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) and uNGAL/uCr ratio (R= -0.567, p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) decreased with increasing birth weight (Fig.\u0026nbsp;3, Fig.\u0026nbsp;4). Females had significantly higher uNGAL levels compared to males (mean 225 vs 165ng/mL; p\u0026thinsp;=\u0026thinsp;0.007).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study provides foundational data on baseline uNGAL concentrations in preterm neonates by different gestational ages during the first week of life. Our results affirm the strong influence of gestational age, birth weight, and sex on uNGAL levels, and underscore the importance of establishing age-specific reference intervals to improve the utility of uNGAL in AKI diagnosis and risk stratification in this population.\u003c/p\u003e\u003cp\u003eWe observed an inverse relationship between gestational age and both raw and normalized uNGAL concentrations, consistent with previous smaller studies. The higher values in earlier gestational ages likely reflect either immature tubular function and increased permeability of the glomerular barrier and/or physiologically higher levels of NGAL during tubular maturation. These findings validate the need to interpret uNGAL values within the context of developmental maturity. Sex-based differences in uNGAL have been previously reported and were confirmed here. Possible explanations include sex-based differences in tubular enzyme expression, hormonal effects, and differences in urinary white blood cell (WBC) excretion and the potential for subclinical or asymptomatic leukocyturia, which is more prevalent in females \u003csup\u003e[\u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eThe use of the unGAL/uCr ratio to normalize urine concentration variability adds robustness to our findings. This approach is particularly relevant in preterm infants, where fluid status and urine output may fluctuate widely and affect baseline biomarker concentration.\u003c/p\u003e\u003cp\u003eStudy strengths include a robust number of ELGANs. Detailed personalized chart reviews were conducted on each subject to search for comorbidities so that infants could be excluded as appropriate. Our study is limited by its single-center design and reliance on spot urine samples rather than timed collections. We also excluded infants with AKI, NEC, sepsis, and PDA treatment, which, while necessary for establishing normative data, limits generalizability to all ELGAN populations.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eBaseline urinary neutrophil gelatinase-associated lipocalin (uNGAL) levels were shown to be elevated in preterm neonates. NGAL is detectable in the urine as early as 23 weeks gestation and its\u0026rsquo; concentration decreases with increasing gestational age. Additionally, baseline uNGAL levels decrease with increasing birth weight and are higher in female neonates compared to male neonates. These findings underscore the variability of uNGAL levels based on gestational age, birth weight, and sex, highlighting the need for further studies to establish precise reference intervals for uNGAL in preterm neonates.\u003c/p\u003e\u003cp\u003eEstablishing these reference intervals is crucial for improving the diagnostic utility of uNGAL as a non-invasive and blood-sparing biomarker for early detection of AKI in this vulnerable population. Early detection of AKI using uNGAL could potentially lead to timely interventions and better clinical outcomes, as it allows for the identification of kidney injury before changes in urine output or serum creatinine levels become apparent. Future research should focus on larger cohorts and diverse populations to validate these findings and refine the use of uNGAL in clinical practice.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eThe authors have no financial conflicts of interest to disclose. This study was approved by the IRB at Nationwide Children’s Hospital. The study was performed in accordance with the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003eDrs. Nicole Asdell and Tahagod Mohamed conceptualized and designed the study.\u003cbr\u003e\u0026nbsp;Dr. Nicole Asdell performed chart review and drafted the original paper.\u003cbr\u003e\u0026nbsp;Shivam Joshi analyzed data and created figures.\u003cbr\u003e\u0026nbsp;All authors contributed to manuscript writing and editing and approved the final draft.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eJetton JG, Boohaker LJ, Sethi SK, et al. 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Urinary NGAL in premature infants. \u003cem\u003ePediatr Res\u003c/em\u003e. 2008;64(4):423\u0026ndash;428. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1203/PDR.0b013e318181b4c1\u003c/span\u003e\u003cspan address=\"10.1203/PDR.0b013e318181b4c1\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMohamed D, et al. Urinary Neutrophil Gelatinase-Associated Lipocalin Values in Preterm Neonates: A Systematic Review and Meta-analysis. \u003cem\u003eAm J Perinatol\u003c/em\u003e. 2024;41(3):e1-e9. doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1055/a-2417-4087\u003c/span\u003e\u003cspan address=\"10.1055/a-2417-4087\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLu Y, Fan Y, et al. 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Increased urinary neutrophil gelatinase associated lipocalin in urinary tract infections and leukocyturia. Clin Chem Lab Med. 2011;49(6):999\u0026ndash;1003. doi: 10.1515/CCLM.2011.156. Epub 2011 Mar 11. PMID: 21391867.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMorita Y, Kurano M, Tanaka M, Hisasue T, Sato M, Ono Y, Sato T, Shukuya K, Yatomi Y. Midstream urine sampling is necessary for accurate measurement of the urinary level of neutrophil gelatinase-associated lipocalin in healthy female subjects. Clin Biochem. 2020;79:70\u0026ndash;74. doi: 10.1016/j.clinbiochem.2020.03.005. Epub 2020 Mar 14. PMID: 32184106.\u003c/span\u003e\u003c/li\u003e\u003c/ol\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":"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":"","lastPublishedDoi":"10.21203/rs.3.rs-7179930/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7179930/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e Acute kidney injury (AKI) is common in preterm neonates and is associated with morbidity and mortality. Urinary neutrophil gelatinase-associated lipocalin (uNGAL) is a promising biomarker for early AKI detection, but its clinical utility is hindered by a lack of normative reference ranges in preterm infants.\u003cbr\u003e\n\u003cstrong\u003eObjective:\u003c/strong\u003e To characterize baseline uNGAL concentrations during the first postnatal week in preterm neonates without AKI and evaluate associations with gestational age (GA), birth weight (BW), and sex.\u003cbr\u003e\n\u003cstrong\u003eMethods:\u003c/strong\u003e Retrospective cohort study of 100 neonates \u0026lt;32 weeks’ gestation without AKI, NEC, sepsis, or UTI. uNGAL and uNGAL/uCr ratios were measured and analyzed by GA, BW, and sex.\u003cbr\u003e\n\u003cstrong\u003eResults:\u003c/strong\u003e uNGAL and uNGAL/uCr levels decreased with increasing GA and BW (p\u0026lt;0.001). Females had higher uNGAL levels than males (p=0.007)\u003cbr\u003e\n\u003cstrong\u003eConclusions:\u003c/strong\u003e Baseline uNGAL varies with GA, BW, and sex in preterm neonates. Development of age-specific reference ranges would enhance the diagnostic utility of uNGAL in neonatal AKI.\u003c/p\u003e","manuscriptTitle":"Urinary Neutrophil Gelatinase-Associated Lipocalin Concentration: A Baseline Study for Establishing Reference Ranges in Preterm Neonates","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-08-08 16:17:57","doi":"10.21203/rs.3.rs-7179930/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"revise","date":"2025-10-15T13:54:34+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"This content is not available.","date":"2025-10-02T05:01:00+00:00","index":3,"fulltext":"This content is not available."},{"type":"editorInvitedReview","content":"This content is not available.","date":"2025-10-01T05:05:40+00:00","index":2,"fulltext":"This content is not available."},{"type":"reviewerAgreed","content":"This content is not available.","date":"2025-09-30T07:25:49+00:00","index":3,"fulltext":"This content is not available."},{"type":"editorInvitedReview","content":"This content is not available.","date":"2025-08-26T20:49:15+00:00","index":1,"fulltext":"This content is not available."},{"type":"reviewerAgreed","content":"This content is not available.","date":"2025-08-23T15:46:05+00:00","index":2,"fulltext":"This content is not available."},{"type":"reviewerAgreed","content":"This content is not available.","date":"2025-08-19T10:43:42+00:00","index":1,"fulltext":"This content is not available."},{"type":"reviewersInvited","content":"","date":"2025-08-05T03:29:52+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-24T09:29:36+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Perinatology","date":"2025-07-23T19:56:55+00:00","index":"","fulltext":""},{"type":"checksFailed","content":"","date":"2025-07-22T10:41:25+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-21T17:32:50+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":"3d49cfbc-f593-460d-bdb1-1f2ef4e99f66","owner":[],"postedDate":"August 8th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":52645682,"name":"Health sciences/Biomarkers/Predictive markers"},{"id":52645683,"name":"Biological sciences/Developmental biology"}],"tags":[],"updatedAt":"2026-02-28T18:05:46+00:00","versionOfRecord":[],"versionCreatedAt":"2025-08-08 16:17:57","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7179930","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7179930","identity":"rs-7179930","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}