ACQUIRED DRUG-RESISTANCE IN MYCOBACTERIUM-TUBERCULOSIS ISOLATES RECOVERED FROM COMPLIANT PATIENTS WITH HUMAN IMMUNODEFICIENCY VIRUS-ASSOCIATED TUBERCULOSIS

We describe five compliant patients with human immunodeficiency virus (HIV)-associated tuberculosis (TB) that relapsed, with acquisition of resistance by the original Mycobacterium tuberculosis strains. Both th e first and second isolates from each patient had the same IS (inserti on sequence) 6110-based DNA fingerprint patterns. Three of the five pa tients developed TB that was resistant to rifampin alone; no mutation in the region of the rpoB gene was detected by a line probe assay in t wo of the isolates from these patients. We discuss several factors pre sumably associated with acquired drug resistance in HIV-infected patie nts, including exogenous reinfection, drug interactions, malabsorption of drugs, and the presence of a large organism burden.