Frequency of Legionella Infection in Patients with Community-Acquired Pneumonia / 대한진단검사의학회지

ABSTRACT

BACKGROUND: Legionella spp. cannot be cultivated in routine bacterial culture media, causing underdiagnosis of community-acquired pneumonia (CAP) due to this microorganism. The purpose of this study was to evaluate the prevalence of legionellosis in patients with CAP by using several diagnostic techniques. METHODS: Patients' sputum, serum and urine samples were collected from 38 patients with CAP in Pusan National University Hospital during November 2002 to May 2004. The laboratory procedures for diagnosis of legionellosis was performed by sputum cultures, urine antigen tests, nucleic acid amplification tests, and serologic indirect immunofluorescence antibody tests. RESULTS: Legionella pneumonia was diagnosed in 2 of the 38 patients (5.3%); one was L. pneumophila serogroup 1 positive in urine, and the other was serum IgG antibody positive for L. micdadei. CONCLUSIONS: Legionellosis may play an important role in adult CAP in Korea. The diagnosis of legionellosis may require various testing methods, such as sputum culture, urine antigen test, nucleic acid amplification test, and serologic antibody test.