Isolation of Legionella pneumophila serogroup 3 from pericardial fluid in a case of pericarditis.

A 43-year-old woman was hospitalized for fulminant pericarditis. During diagnostic work-up, an as yet unknown bronchial carcinoma was detected. In the pericardial exudate Legionella pneumophila serogroup 3 was demonstrated by direct fluorescent antibody technique and by culture. In a lung biopsy L. pneumophila serogroup 3 was found, too. Using an antigen-ELISA for L. pneumophila serogroup 1, antigenuria was demonstrated. In cases of pericarditis negative for common bacterial pathogens, all diagnostic tests for legionellae, e.g. culture, antigen detection in pericardial, pleural effusion and urine and antibody detection should be included in the diagnostic programme.