Background: Pulmonary involvement is common in leptospirosis and usually characterized by hemoptysis, dyspnea and diffuse bilateral infiltrates in chest X-rays. Such findings may be compatible with alveolar hemorrhage, already described by some authors both in autopsies and bronchoalveolar lavage (BAL). Objective: To evaluate the presence of alveolar hemorrhage, diagnosed through BAL, in bearers of leptospirosis patients with pulmonary involvement emphasizing the method's importance for early detection of this complication. Method: Seven patients with leptospirosis were submitted to BAL. All presented respiratory symptoms and/or infiltrates in the chest X-rays and/or hypoxemia. Alveolar hemorrhage was defined by the following findings in BAL: percentage of siderophages e"20% and/or Golde score >100 and/or hemorrhagic fluid. Culture and direct tests for leptospirosis were performed in BAL. Diagnosis of disease was confirmed by microscopy serum agglutination. Results: The aspect of the bronchoscopy was normal in five patients, showed blood in the bronchial tree in one case and inflammatory manifestations in another. The BAL aspect was hemorrhagic for all patients portraying alveolar hemorrhage. Culture and direct tests were negative for Leptospiras in the BAL. Conclusions: Leptospirosis must be taken into account in the differential diagnosis of alveolar hemorrhage. The BAL was confirmed as an efficient method for detection of alveolar hemorrhage in leptospirosis, to recommend immediate therapy for the purpose of preventing its evolution to massive hemoptysis and respiratory failure.

Keywords: Leptospirosis. Bronchoalveolar lavage fluid. Radiography, thoracic.