OBJECTIVES: Acute kidney injury (AKI) during dengue infection has been stratified by several definitions which resulted in variations in reported incidence and clinico-laboratory characteristics of AKI. We conducted a retrospective study to compare three commonly used definitions of AKI among dengue patients in order to emphasize the uniformity of definition for future studies.

METHODS: A total 413 dengue patients were defined and staged according to conventional definition (CD), AKIN and RIFLE criteria. All three definitions were compared by using Chi-square, student t test and one way ANOVA. Logistic regression was used to determine predictors of AKI.

RESULTS: The incidence of AKI was 12.4%, 11.3% and 5.1% by using AKIN, RIFLE and CD respectively. AKIN and RIFLE criteria were comparable but higher number of patients were stratified as AKIN-I as compared to RIFLE-R (67.8% vs 71.4% respectively). The patients stratified by CD were severe cases with worse form of dengue and AKI. Overall mortality was 1.4% and increased fatal cases were observed in worse AKIN and RIFLE stages. A total 8 risk factors of AKI were identified with AKIN criteria followed by 7 and 4 risk factors by RIFLE and CD respectively. ROC curve analysis demonstrated excellent prediction accuracy of AKIN, RIFLE and CD regression models with AUC = 0.931, 0.930, 0.911 respectively.

CONCLUSIONS: The AKIN and RIFLE classifications were comparable and identified more AKI patients than CD. Use of different classifications to define AKI affects incidence, clinico-laboratory characteristics and results of multivariate analysis in dengue patients. Therefore a consensus to define AKI is needed for uniformity of research findings. The implication of newer classifications (i.e. AKIN and RIFLE) should be a part of routine clinical practice for better understanding of disease course.