Pneumonia due to Leptospira spp.: results of an epidemiological and clinical study.

Objective: To evaluate the prevalence of Leptospira spp. infections in a population of in- and out-patients with community acquired pneumonia (CAP) and the incidence of leptospiral pneumonia.
Design and Results: Of 176 patients infected with CAP who were evaluated for the presence of Leptospira spp. as causative agent, 10 were found positive for leptospiral antibodies (prevalence rate: 5.7%), but seroconversion was observed in only one case (incidence rate: 0.6%). The patient had had recent contact with possibly contaminated water. She had pulmonary involvement and signs of mild hepatic damage, but recovered fully.
Conclusion: The authors highlight the importance of testing for leptospirosis in case of pneumonia in endemic areas where the more common causative pathogens for CAP can not be documented and when initial empiric therapy is ineffective.