Thrombocytopenia in leptospirosis.

In a retrospective study undertaken to document the frequency of thrombocytopenia in cases of leptospirosis, 18 of 32 patients (56.3%) had a platelet count of 100 x 10(3)/mm3 or less. Renal failure occurred in 72.2% of thrombocytopenic patients and in 21.4% of patients with normal platelet counts. The association of thrombocytopenia and renal failure was significant (P less than 0.02). The common occurrence of thrombocytopenia and its association with acute renal failure in patients with leptospirosis has not previously been reported.