Pulmonary Disease From Nontuberculous Mycobacteria in Patients With Human Immunodeficiency Virus: Mycobacterium xenopi
Mycobacterium xenopi is a nonchromogenic mycobacterial species with antigenic similarity to MAC. It is commonly cultured from water sources and grows optimally at somewhat higher temperatures (42 to 43°C) than other mycobacteria. Outbreaks of human infection have been associated with contaminated hospital water supplies.
Pulmonary disease resembling tuberculosis has been reported in immunocompetent hosts (many of whom had preexisting lung disease) and in immunocompromised groups, including transplant recipients receiving immunosuppressive drugs comments buy allegra online. Shafer and Sierra reviewed NTM cultures from Kings County Hospital in Brooklyn, NY, and found that M xenopi was the most common species cultured after MAC and M gordonae and that having a positive culture for M xenopi was significantly associated with HIV infection.
Most patients with positive cultures had concurrent opportunistic infections and the clinical significance of infection with M xenopi was not clear. Tenholder et al reviewed NTM cultures from 36 bronchoalveolar lavage specimens. Mycobacterium xenopi was cultured from five patient specimens but was not believed to be pathogenic in any. Eng et al in 1984 reported a case of a 32-year-old man with AIDS who had reticular pulmonary infiltrates, cough, fever, and hepatomegaly. Mycobacterium xenopi was cultured from multiple sputum samples and from a liver biopsy specimen. This patient responded favorably to treatment with isoniazid, rifampin, and pyrazinamide. In another case report, a young woman with cough, lethargy, night sweats, and bilateral apical infiltrates was treated empirically for tuberculosis after initial sputum and bronchoscopy studies were unrevealing. Three months later, multiple sputum cultures were positive for M xenopi. The patient continued intermittently to receive antituberculous therapy with sterilization of sputum cultures, but died of other complications of HIV infection. Disseminated infection with M xenopi appears to be very uncommon; Shafer and Sierra described one patient with M xenopi bacteremia and AIDS without clinical details.
Category: Respiratory Symptoms
Tags: AIDS, atypical Mycobacterium infections, HIV infection, Mycobacterium avium-intracellulare infection