Factors associated with thrombocytopenia in severe leptospirosis (Weil’s disease)

OBJECTIVE: This study was conducted to investigate factors associated with thrombocytopenia in a large cohort of patients with leptospirosis in an endemic area. METHODS: This retrospective study included 374 consecutive patients with leptospirosis who were admitted to tertiary hospitals in Fortaleza, Brazil. All patients had a diagnosis of severe leptospirosis (Weil’s disease). Acute kidney injury was defined according to the RIFLE criteria. Thrombocytopenia was defined as a platelet count,100,000/mm3. RESULTS: A total of 374 patients were included, with a mean age of 36.1¡15.5 years, and 83.4 % were male. Thrombocytopenia was present at the time of hospital admission in 200 cases (53.5%), and it developed during the hospital stay in 150 cases (40.3%). The patients with thrombocytopenia had higher frequencies of dehydration (53 % vs. 35.3%, p=0.001), epistaxis (5.7 % vs. 0.8%, p=0.033), hematemesis (13 % vs. 4.6%, p=0.006), myalgia (91.5 % vs. 84.5%, p=0.038), hematuria (54.8 % vs. 37.6%, p=0.011), metabolic acidosis (18% vs. 9.2%, p=0.016) and hypoalbuminemia (17.8 % vs. 7.5%, p=0.005). The independent risk factors associated with thrombocytopenia during the hospital stay were lengthy disease (OR: 1.2, p=0.001) and acute kidney injury (OR: 6.6, p=0.004). Mortality was not associated with thrombocytopenia at admission (12.5 % vs. 12.6%, p=1.000) or during the hospital stay (12.6 % vs. 11.3%, p=0.748). CONCLUSIONS: Thrombocytopenia is a frequent complication in leptospirosis, and this condition was present i