these assays were compared with the previously standardized indirect immunofluorescence test in four groups of subjects : ( i ) pneumonia patients with culture-proven legionnaires disease with serogroup 1 isolates , ( ii ) pneumonia patients with serogroup 1 organisms detected by direct immunofluorescence testing of respiratory secretions but without culture confirmation , ( iii ) pneumonia patients with negative culture and direct immunofluorescence tests , and ( iv ) healthy hospital employees .
C0023241
legionnaires disease
C0032285
pneumonia