Accuracy of acute kidney injury diagnosis in the neonatal intensive care unit

low birthweight (VLBW, i.e., <1500 grams) infants that are associated with cortisol checks and (2) investigate associations between cortisol and acute kidney injury (AKI).Methods Used: We conducted a single-center retrospective chart review of VLBW infants admitted between 1/1/18-12/31/20.AKI was diagnosed using the neonatal modified Kidney Disease: Improving Global Outcomes (KDIGO) serum creatinine criteria.Comparisons between those with and without cortisol levels drawn were made using Chi Square, Fisher's Exact, Student's T, and Wilcoxon Rank Sum Test as appropriate.Bivariate and multivariate generalized linear mixed modeling was used to examine associations between cortisol and AKI.Summary of Results: Of 567 infants, 154 (27.2%) had cortisol levels drawn in the NICU.Birth weight (cortisol: 821 ± 245 grams vs no cortisol: 1165 ± 248 grams), gestational age (26.1 ± 2.5 weeks vs 29.3 ± 2.4 weeks), gender (male 56.5% vs 45.5%), pre-eclampsia (27.9% vs 40.4%), chorioamnionitis (9.1% vs 3.4%), intrauterine growth restriction (7.8% vs 14%), preterm labor (48.7% vs 35.1%),APGAR (1 minute 4 [2,6] vs 5 [3,4]; 5 minutes 7 [2,6] vs 8 [2,7]) (all p < 0.05).Among those with cortisol checks, 286 cortisol levels were drawn, with a median cortisol 6 mg/dL IQR [2.8,11.9]and a mean 2.0 ± 1.7 levels drawn per patient.Cortisol levels were drawn at median 10 days of life [1.5,21.5].AKI occurred in 130 (22.9%).When examining associations between cortisol checks and AKI, neonates who had a cortisol level checked were at increased risk for AKI, recurrent AKI, and increased length of stay (LOS, median 115 [89,140] days vs 48 [28,75] days; aRR 1.00 95% CI 1.002-1.005;p < 0.01) after adjusting for potential confounders (Table ).No association was detected between cortisol and AKI severity by KDIGO stage.Conclusions: There were significant differences in baseline and demographic characteristics in our cohort when comparing VLBW infants who did and did not have cortisol levels drawn in the NICU.Those with cortisol levels drawn were at increased risk for AKI, recurrent AKI, and had lengths of stay nearly 2.5× higher than those without cortisol levels checked.Further investigations into the relationship of AKI and cortisol are warranted.