Infection due to nontuberculous Mycobacterium other than MAC in AIDS patients at Siriraj hospital during 1998-2000: saprophyte vs pathogen.

HIV is a major health problem in Thailand. These patients are vulnerable to opportunistic infections, especially Mycobacterium tuberculosis and MAC infection. However, NTM was considered a rare disease in Thailand before the AIDS era. In this study, there were 38 HIV seropositive patients with NTM (other than MAC) identified from clinical specimens during the 3 year period 1998-2000 at Siriraj Hospital, which has a higher prevalence than the previous report. Among these patients, 29 cases were likely to have had definite infection from NTM, 5 cases possibly had NTM as a pathogen, and 4 cases had NTM as colonization. The most common site of infection was the lung (87%) and most common symptoms were cough (62.2%), fever (34.2%), weight loss (42.1%), and lymphadenopathy (5.3%). The outcome was poor because many NTM are not susceptible to standard medication for tuberculosis which is the empirical treatment for the majority of HIV seropositive patients with a clinical finding suspected of mycobacterial infection. The fatality rate was as high as 58.6 per cent. Awareness of NTM as a potential pathogen in HIV seropositive patientsand adjustment of medications even before the availability of culture results may improve the outcome of treatment of NTM infection in HIV seropositive patients.