Document Type: Research article
Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Department of Infectious Disease, Loghman Hospital, Shahid Beheshti University of Medical Sciences
Department of Clinical Pharmacy, School of Pharmacy, Shahid Beheshti University of Medical Sciences
Pathologist director of Khatam laboratory, Khatam hospital
BACKGROUND: Nephrotoxicity has been a major long-standing concern about colistin. This study was designed to compare nephrotoxicity of high dose and conventional dose of colistin.
METHODS: A randomized open-labeled clinical trial on 40 patients with multi-drug resistant gram negative infections was designed. Patients were allocated into two equal-size groups receiving high and conventional dose of colistin. Blood samples were taken on day 1, 3, 5, 7 and 10 of treatment for measuring serum cystatin C (Cys C) levels. Incidence of acute kidney injury (AKI) was also evaluated based on RIFLE criteria.
RESULTS: Mean±sd of the difference between baseline and day 10 Cys C levels in high dose and conventional dose groups were 1.61±0.90 and 1.32±0.48, respectively (P=0.30). Within group analysis showed increase in Cys C levels in both groups (P= 0.001), however, no significant difference in Cys C levels was seen in between groups analysis (P=0.13). Prevalence of AKI based on RIFLE criteria was 60% and 15% in high dose and conventional dose groups, respectively (P= 0.003). Comparison of Cys C between AKI (mean±sd) and non-AKI (mean±sd) patients, irrespective of colistin dosage regimens, confirmed a significant difference (P< 0.0001).
CONCLUSION: Although, colistin-induced nephrotoxicity, determined by Cys C levels, was not confirmed by our findings, however, higher incidence of AKI in high-dose group, defined by RIFLE criteria, along with higher levels of Cys C in AKI patients are supportive of the higher risk of renal toxicity associated with high-dose regimen of colistin.