[Legionnaires' disease: a cause of pulmonary fibrosis and bronchopulmonary disease? (author's transl)].

Antibody titres against Legionella pneumophila (serogroups 1 and 2) were determined by the indirect immunofluorescence test on 206 patients with various forms of bronchopulmonary disease. In one third of cases there was a very weak titre (1:32 to 1:64), a moderately to markedly elevated one against one or both bacterial strains (greater than or equal to 1:128) in 4%. In one of four cases with a titre greater than or equal to 1:512 Legionnaires' disease, contracted via an air-conditioning unit, was suspected. In another case there was probably chronic Legionnaires' disease with subsequent pulmonary fibrosis. In the remaining two cases chronic Legionnaires' disease was the likely diagnosis, the clinical picture being one of nonspecific bronchopneumonia. These findings suggest that the causative organism of Legionnaires' disease is widespread also in Southern Germany and that the disease does not always lead to severe pneumonic complications.