Objective: Acute kidney injury (AKI) is still an important cause of morbidity and mortality in the neonatal period, despite recent improvements on perinatal care. In this study, the frequency, etiological causes, clinical characteristics, and mortality of newborns with AKI in a tertiary neonatal intensive unit (NICU) were investigated.

Methods: Medical records of newborns admitted between 2007 and 2011 were evaluated and patients who developed AKI in the first 28 days of life were determined. Clinical characteristics, primary cause, mortality, and highest creatinine of newborns with AKI were recorded.

Results: It was determined that 94 of 677 (13.9%) patients (80% of them in the first seven days of life) developed AKI. Hypovolemia, birth asphyxia, congenital heart disease, sepsis, and genitourinary system (GUS) anomalies were found to be the most frequent causes of AKI. The incidence of AKI and mortality rates were higher in patients with gestational age under 28 week and birth weight under 1000 g. Mortality tends to rise in the presence of AKI regardless of the underlying disease, but this was statistically significant only for sepsis and cardiac disease. The presence of AKI increases length of stay and, the creatinine level was found to be lower in those who survived.

Conclusion: AKI is still an important morbidity in patients treated in NICU despite improvement on perinatal care. Low birth weight, prematurity, birth asphyxia, sepsis, hypovolemia, cardiac diseases, and GUS anomalies were common causes and mortality increases in patients with AKI regardless of gestational age, birth weight, and underlying etiology.

Keywords: Newborn, neonatal intensive care unit, acute kidney injury