Introduction: Acute kidney injury is associated with high mortality in critically ill patients. We usually measure serum creatinine to detect AKI, but it is a poor predictor of accuracy particularly in the early stages of AKI⁽¹⁾. We studied the utility of urinary cystatin C and its significance in AKI.

Materials and Methods: This prospective observational study was done in 83 critically ill patients admitted in ICU. Serum creatinine was done on day 1 and day 3 which was compared with Urinary Cystatin C done on day 1.

Results:  Out of the 83 patients, 36 (43.3%;) developed AKI. Serum creatinine on day 1 and  day 3 were compared with urinary cystatin C  done on day 1. We observed that in the AKI group there was significant elevation of urinary cystatin C (15% (p=0.001)). On contrary in the non AKI group there was a marginal level of increase in urinary cystatin C. As the urinary cystatin C is the early excretory product it can be used as an early biomarker of AKI.

Conclusions: We found that the urinary cystatin C levels were significantly elevated in AKI groups when compared with the creatinine levels. Hence we suggest that urinary cystatin C is a significant early biomarker for AKI. Moreover, further studies are warranted with large number of sample size with multicentric population to confirm these results

Keywords: urinary cystatin C, acute kidney injury, critically ill patients.

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