Systemic Nocardiosis as Unusual Clinical Onset of Late Advanced HIV Infection: A Case Report

Abstract

The genus Nocardia includes aerobic actinomycetes causing disease in both humans and animals. Nocardiosis is a rare bacterial infection, but the incidence of human disease has increased in the recent years in association with an increasing population of immune-compromised hosts and the improved methods for detection and identification of Nocardia spp. in the clinical laboratory. All those situations of immune-system compromise are conditions associated with increased risk, especially when cell-mediated immunity is involved. The prognosis depends both upon the immediacy of therapy initiation, concomitant disorders and the immune status of the patient. Recently cases of multi-drug resistance nocardiosis and the epidemiology and drug susceptibility of less common Nocardia species have been described. In HIV positive patients pulmonary nocardiosis, the most common clinical presentation, has a low reported prevalence of 0.3%, and it is not considered an AIDS-defining disease. The difficulties in isolation, the non-specific clinical and radiologic presentation, and the widespread use of cotrimoxazole (TMP/SMX) prophylaxis could be responsible for this low prevalence. In this paper, it is described a rare and fatal case of systemic nocardiosis arising with chest pain in a patient with a severe immune deficiency, unaware of his HIV positivity. Systemic nocardiosis is generally caused by <i>N. asteroids</i> and the prognosis is good, but in patients with AIDS, mortality in disseminated forms with central nervous system involvement is more than 50%.