Pulmonary infection with Nocardia species: a report of 10 cases and review

Abstract

Pulmonary nocardiosis (PN) is an infrequent and severe infection due to Nocardia spp., microorganisms that may behave both as opportunists and as primary pathogens. The aim of this study and review was to evaluate the clinical features, evolution and prognostic factors of PN.The study group comprised 10 consecutive patients with pulmonary nocardiosis acquired in a community setting, diagnosed and followed in a tertiary teaching hospital.Chronic obstructive pulmonary disease (COPD), neoplastic disease and human immunodeficiency virus (HIV) infection were the most frequent predisposing factors. Four patients were receiving corticosteroid treatment. Clinical course was chronic and diagnosis was delayed 3 weeks or more in seven of the patients. Lobar or multilobar condensation was the most frequent radiographic pattern. Antimicrobial susceptibility testing showed: 100% sensitivity for amikacin; 83% for imipenem; 71% for cefotaxime; and 71% for trimethoprim-sulphamethoxazole. The disease remained localized in the lung in five cases, with a trend toward chronicity in one with bronchiectasis. In the other five, the disease disseminated, affecting subcutaneous tissue, the central nervous system and the kidney. Three patients died, one with disseminated disease and two who were receiving corticosteroid therapy.The following conclusions were reached: 1) pulmonary nocardiosis is difficult to diagnose, diagnosis is frequently delayed and a high level of suspicion is, thus, required in patients with underlying diseases or chronic corticosteroid therapy; 2) there is frequent dissemination and high mortality; and 3) antimicrobial combinations with proven synergy, such as imipenem and amikacin, are recommended for initial therapy. Eur Respir J 1997; 10: 1542-1546

HIV-Associated Bacterial Pneumonia

“…Nocardia is an aerobic actinomycete that can cause infections, including pneumonia, usually in association with immunosuppression, including HIV infection [67,68]. The clinical course is often chronic, although dissemination can occur and be associated with a high mortality [68].…”

“…The clinical course is often chronic, although dissemination can occur and be associated with a high mortality [68]. The diagnosis is frequently delayed and a high index of suspicion is required [68]. Treatment with antimicrobial agents with proven synergy is recommended for initial therapy [68].…”

“…The diagnosis is frequently delayed and a high index of suspicion is required [68]. Treatment with antimicrobial agents with proven synergy is recommended for initial therapy [68].…”

Diagnosis of Nocardial Infection by Microscopic Analysis of Infected Specimens

“…The clinical manifestations of infection are non-specific, including fever, fatigue, productive cough, dyspnea, pleuritic chest pain and weight loss (2,4). The most frequent radiographic abnormality is consolidation of variable size which may cavitate (3)(4)(5). Single or multiple nodules are common (5).…”

“…Pulmonary nocardiosis likely arises from inhalation of organisms from contaminated soil. Patients deficient in cell-mediated immunity, especially those receiving systemic corticosteroids, with lymphoma, AIDS, or following transplantation, are at high risk from this opportunistic infection (1)(2)(3)(4). Nocardiosis is also associated with pulmonary alveolar proteinosis, tuberculosis, chronic obstructive pulmonary disease, and chronic granulomatous disease ( 1-3).…”