Pulmonary nocardiosis: Clinical experience in ten cases

Background. Pulmonary nocardiosis is an infrequent infection whose incidenc e seems to be increasing due to a higher degree of clinical suspicion and t he increasing number of immunosuppressive factors. Objective: To study the predisposing factors, clinical characteristics, diagnostic procedures, trea tment and progress of pulmonary nocardiosis (PN). Methods: Review of 10 pat ients (9 male, 1 female, mean age 61) with PN in a 600-bed teaching hospita l, diagnosed from 1992 to 1999. Results: Associated diseases observed were chronic obstructive pulmonary disease (COPD) in 6 patients, human immunodef iciency virus (HIV) infection in 3 and polymyalgia rheumatica in 1. Four pa tients had received oral corticotherapy for COPD for over a year (mean dose 13 mg/day of prednisone or equivalent). The main reason for consultation w as an increase in dyspnea in the patients with COPD (6/6) and fever in thos e with HIV (3/3). Mean time between onset of symptoms and diagnosis was 5 w eeks. In 8 patients, the infection occurred outside the hospital setting. T he infection was restricted to the lung in 9/10; in the remaining case, the central nervous system (CNS) and subcutaneous tissue were affected. Lobar or multilobar consolidation was the most frequent radiographic pattern foun d (6/10). Sputum culture was positive when performed (8 cases). Diagnosis w as made or confirmed by bronchoscopy (bronchoaspirate or protected specimen brush) in 5 patients. Germs isolated were: Nocardia asteroides (8/10), Noc ardia farcinica (1/10), Nocardia otitidiscaviarum (1/10). Cotrimoxazole was the most used empirical treatment (6/10). Resolution was achieved in 5 cas es. Four subjects died: 1 HIV patient with disseminated nocardiosis, and 3 COPD patients, 2 of whom had received long-term corticotherapy. Illness rec urred in only 1 case, due to failure to comply with treatment. Conclusions: (1) In our geographical setting Nocardia presents as a subacute or chronic pulmonary infection, mainly outside the hospital. (2) It tends to affect o nly the lung. (3) Diagnosis requires a high clinical suspicion, and can be made on the basis of a sputum culture. (4) Nocardia tends to attack patient s with underlying COPD, or immunodepressed patients treated with glucocorti coids, or patients with HIV infection. (5) Mortality is high in both COPD a nd HIV patients. (6) In our area, cotrimoxazole seems to be the most common ly prescribed treatment. Copyright (C) 2001 S. Karger AG, Basel.