Renal dysfunction in falciparum - Malaria is detected more often when assessed by serum concentration of cystatin C instead of creatinine

Objectives: To estimate the frequency of renal dysfunction in falciparum malaria by serum concentration of cystatin C, a new sensitive indicator of the glomerular filtration rate (GFR). Methods: Retrospective study of stored sera and patient files. Assessment of renal function by serum concentration of creatinine and cystatin C and comparison of the results from both indicators of GFR. Results: A total of 108 adult patients with falciparum malaria were included in the study. Concentration of creatinine and cystatin C correlated well (r = 0.706; P < 0.001). Elevated cystatin C was more frequent than elevated creatinine (54.6% vs. 20.4%; P < 0.001). Patients older than 50 years developed renal dysfunction more often (P < 0.05) than younger ones. Results from cystatin C and creatinine were concordant in 63 (58.3%) and contradictory in 45 (41.6%) cases. Four (3.7%) patients had elevated creatinine but normal cystatin C levels, hence 63 patients (58.3%) showed elevation of at least one indicator of GFR. The frequency of elevated cystatin C and elevated creatinine was unrelated to body weight, gender or bilirubin level. Conclusions: The prevalence of impaired renal function in patients with falciparum malaria seems to have been underestimated in the past. Using a sensitive marker, 55% of the patients have a reduced GFR.