Pneumonia that is unresponsive to appropriate antibiotic therapy
suggests an infection due to more unusual or resistant organisms. In
this report, a child with unilateral pneumonia, pleural effusion, and
anti-I cold hemagglutinin antibodies is presented. The usual causes of
this clinical picture were suspected and treated, but the child did not
improve. Features of her history suggested a more unusual etiology, and
a diagnosis of leptospirosis was made. A brief discussion of
leptospiral disease in children is provided.