Acute kidney injury without previous renal disease in critical care unit

Background: Acute kidney injury (AKI) is common in hospitalized and critically ill children. Apart from primary kidney disease, etiologies of AKI are usually related to systemic disease and nephrotoxic insult. This study examines the incidence, characteristics, and mortality risks of AKI in critically ill children without primary renal disease or previously known chronic kidney disease. Methods: A retrospective cohort study was conducted of patients aged 1–18 years, diagnosed with AKI (excluding severe glomerulonephritis and previously known chronic kidney disease) in pediatric intensive care units between 2013 and 2016. Acute kidney injury was defined according to the Kidney Disease Improving Global Outcomes classifications. Cox proportional hazards regression analysis was employed to assess the relationship between the risk factors and mortality. Results: Of 1,377 pediatric intensive care unit patients, 253 (18.4%) developed AKI and only 169 (12.3%) who did not have previously known renal disease were included. Of these 169 AKI patients, the mean age was 8.1 ± 4.7 years; 88 (52.1%) patients were male; and 60 (35.5%) patients had AKI stage 3. The most common etiologies of AKI were sepsis (76.9%) and shock (64.5%). Fifty-three (31.4%) of those patients died during admission. The risk factors for death were the need for mechanical ventilation (adjusted hazard ratio, 17.82; 95% CI, 2.41–132.06) and AKI stage 3 (adjusted hazard ratio, 2.32; 95% CI, 1.07–5.00). Conclusions: Acute kidney injury in critically ill children without previously known renal disease was approximately two-thirds of the overall incidence. The risk factors of in-hospital death were the use of mechanical ventilation, and AKI stage 3.