Environmental mycobacterial diseases in patients with and without HIV infection: epidemiology, clinical features and evolution

The objective of the present study was to ascertain the clinical features, risk factors, microbiologic spectrum and course of disease after treatment of infections by environmental mycobacteria (EM) in patients with and witho ut HIV infection in our community. Eighty-eight patients with diseases caus ed by EM diagnosed between 1989 and 1997 were studied; 46 (52.7%) were HIV- positive. Mycobacterium kansasii was the most prevalent pathogen (54%) over all, followed by M. avium complex (40%). However, M. avium complex was most prevalent among HIV-positive patients (61%) and M. kansasii was most preva lent among HIV-negative patients (76%). Localized lung infectious were most common among HIV-negative patients, whereas 74% of HIV-positive patients h ad disseminated disease. Among HIV-negative patients, chronic obstructive p ulmonary disease and corticosteroid use were common associations. Pulmonary disease was subacute and non-specific in both patient groups, whereas abdo minal pain was the first symptom of most patients with disseminated disease . On the chest films of 76% of the HIV-negative patients, we observed cavit ation and infiltrates; 60% of HIV-negative patients had normal x-rays. No d ifferences in antibiotic sensitivity were observed between strains from HIV -positive and HIV-negative patients. The prognosis was good in the HIV-nega tive group with combined therapy with 2 to 4 first-line antituberculous dru gs, whereas response was poor in HIV-positive patients in spite of prolonge d treatment with 3 to 5 drugs. Nevertheless, thanks to the highly effective anti-retroviral treatment of recent years, we seem to be observing improve d response to therapy with less aggressive forms of EM disease.