The aim of this study was to determine the clinical characteristics and outcomes of critically ill adults with septic acute kidney injury (AKI) stratified according to the AKI staging. The Acute Kidney Injury Network (AKIN) definition for AKI had been shown to predict important clinical outcomes such as hospital mortality 1. Sepsis is the most common cause of AKI resulting in worse clinical outcomes when compared with other causes 2.

An observational study conducted in a medical ICU of a general hospital in Singapore over a 6-month period. Patients who were admitted to the ICU with a diagnosis of sepsis and AKI (as defined by the AKIN criteria) were prospectively enrolled. The clinical characteristics and outcomes were determined and stratified according to the AKIN criteria.

A total of 71 consecutive septic patients (60.6% Chinese, 32.4% Malays, 2.8% Indians) were enrolled. The mean age was 63.7 years with a male predominance of 67.6%. The median Simplified Acute Physiology Score (SAPS) II score was 54. The majority (60.6%) was AKI III, with 22.9% in stage II and 16.9% in stage I. Overall hospital mortality was 39.4%. Patients who met septic AKI III had significantly higher mortality compared with AKI I and II (55.8% vs. 16.7% and 12.5%, respectively, P < 0.001). There was a significant difference in the mean SAPS II score between the dead and alive patients (70 vs. 46, P < 0.001). Multiple logistic regression analysis showed that AKI III (OR = 5.75, 95% CI = 1.2 to 25.5) and SAPS II score ≥ 65 (OR = 15.6, 95% CI = 3.5 to 68.2) were found to be independent predictors of hospital mortality.

In septic patients, AKI III appeared to be a strong predictor of hospital mortality. This finding is similar to a previous study 3, which also showed that in patents with AKI only AKI III was an independent risk factor for hospital death.