Thrombocytopenia and acute renal failure in Puumala hantavirus infections.

Nephropathia epidemica, caused by Puumala virus (PUUV) infection, is a form of hemorrhagic fever with renal syndrome of variable severity. Early prognostic markers for the severity of renal failure have not been established. We evaluated clinical and laboratory parameters of 15 consecutive patients with acute PUUV infection, which is endemic in the Alb-Danube region, South Germany. Severe renal failure (serum creatinine >620 micromol/L) was observed in seven patients; four required hemodialysis treatment. Low platelet count (<60 x 109/L), but not leukocyte count, C-reactive protein, or other parameters obtained at the initial evaluation, was significantly associated with subsequent severe renal failure (p = 0.004). Maximum serum creatinine was preceded by platelet count nadirs by a median of 4 days. Thrombocytopenia <60 x 109/L appears predictive of a severe course of acute renal failure in nephropathia epidemica, with potential value for risk-adapted clinical disease management.