Isolation of a novel sequevar of Mycobacterium flavescens from the synovial fluid of an AIDS patient.

This report describes the characterisation of a mycobacterium involved in a case of septic arthritis in an AIDS patient that was treated successfully with specific anti-mycobacterial drugs. The biochemical and cultural features, and the mycolic acid pattern as assessed by high-performance liquid chromatography, were fully compatible with the isolate being Mycobacterium flavescens. However, the isolate's 16S rDNA sequence differed by five nucleotides from the two known sequevars of M. flavescens, thus indicating that this isolate belonged to a new 16S rDNA sequevar.