Introduction: Acute kidney injury (AKI) in neonates is a frequently disregarded morbidity within the intensive care unit (ICU).
Aim of the study: was to measure the serum beta2-microglobulin level in high-risk neonates in order to predict AKI injury early. 
Methods: This cross-sectional research was performed on 40 critically ill neonates who got admitted to our Hospital NICU.
Results: AKI occurred in 72.5% of study group. Regarding renal functions, no statistically significant disparity was seen among the groups with regards to creatinine and urea levels on the first day. However, serum creatinine 2nd day was statistically significantly higher among AKI group (p<0.001). In the group with AKI, the GFR was substantially lower in comparison to the group without AKI (p0.001). Nevertheless, regarding UOP, a lack of statistical significance was observed between the groups. In our study, serum beta2-microglobulin level at day 1 and 3 were statistically significantly greater among the AKI group than the non-AKI group (p<0.001). ROC curve analysis disclosed that serum beta2-microglobulin level on day 1 and day 3 could be an excellent predictive test of AKI. Serum beta2-microglobulin was significant on Day 1 and Day 3, with corresponding cutoff values with an area under the curve (AUC) values of 0.91 and 0.92 for Day 1 and Day 3, respectively with the sensitivities (82.8%) and specificities (81.8%) for both time points were comparable.
Conclusion: Serum beta2-microglobulin level may serve as promising biomarker for risk assessment and early detection of AKI in newborns that are seriously ill.