Patterns of anti-tuberculosis drug resistance among HIV-infected patients in Maputo, Mozambique, 2002-2003.

SETTING: Two tuberculosis (TB) reference hospitals in Maputo, Mozambique. OBJECTIVES: To assess the pattern of TB drug resistance and its risk factors in human immunodeficiency virus (HIV) patients. DESIGN: Adult HIV-positive patients with TB diagnosed by culture of sputum or bronchial washing were enrolled during 2002-2003. Cultures of 111 patients were tested for rifampicin, isoniazid, streptomycin and ethambutol sensitivity. Chest X-ray, haemoglobin (Hb), total lymphocyte and CD4 counts were also performed. RESULTS: Overall resistance to any drugs was found in 18% and multidrug-resistant TB (MDR-TB) in 9%. New cases of TB accounted for 62% of the studied group. Drug resistance in this subgroup was 13% compared with 26.3% in the previously treated subgroup, and MDR-TB was 5.8% vs. 15.8%. All patients presented Hb levels < 9 g/dl and total lymphocyte counts < 1200/microl. CD4 counts were significantly low in the drug resistance subgroup, with levels mostly < 100/microl. Cavities on X-ray were seen only in drug-sensitive patients. No risk factors for drug resistance were detected. CONCLUSIONS: Overall observed drug resistance was 18%, and MDR-TB 9%. Previously treated patients had high drug resistance (26.3%) and MDR-TB (15.8%).

IS1245 restriction fragment length polymorphism typing of Mycobacterium avium from patients admitted to a reference hospital in Campinas, Brazil

Mycobacterium avium is an important pathogen among immunodeficient patients, especially patients with AIDS. The natural history of this disease is unclear. Several environmental sources have been implicated as the origin of this infection. Polyclonal infection with this species is observed, challenging the understanding of its pathogenesis and treatment. In the present study 45 M. avium strains were recovered from 39 patients admitted to a reference hospital between 1996 and 1998. Species identification was performed using a species-specific nucleic acid hybridization test (AccuProbe«) from Gen-Probe«. Strains were genotyped using IS1245 restriction fragment length polymorphism typing. Blood was the main source of the organism. In one patient with disseminated disease, M. avium could be recovered more than once from potentially sterile sites. Strains isolated from this patient had different genotypes, indicating that the infection was polyclonal. Four patient clones were characterized in this population, the largest clone being detected in eight patients. This finding points to a common-source transmission of the organism

IS1245 restriction fragment length polymorphism typing of Mycobacterium avium from patients admitted to a reference hospital in Campinas, Brazil.

Mycobacterium avium is an important pathogen among immunodeficient patients, especially patients with AIDS. The natural history of this disease is unclear. Several environmental sources have been implicated as the origin of this infection. Polyclonal infection with this species is observed, challenging the understanding of its pathogenesis and treatment. In the present study 45 M. avium strains were recovered from 39 patients admitted to a reference hospital between 1996 and 1998. Species identification was performed using a species-specific nucleic acid hybridization test (AccuProbe) from Gen-Probe. Strains were genotyped using IS1245 restriction fragment length polymorphism typing. Blood was the main source of the organism. In one patient with disseminated disease, M. avium could be recovered more than once from potentially sterile sites. Strains isolated from this patient had different genotypes, indicating that the infection was polyclonal. Four patient clones were characterized in this population, the largest clone being detected in eight patients. This finding points to a common-source transmission of the organism.