Mycobacterial infection of the musculoskeletal tissues: the use of pathological specimens for identification of causative species by PCR-direct sequencing of 16S rDNA.

Mycobacterial infection of musculoskeletal tissue is a rare disease that may cause destruction of the tissues. Both Mycobacterium tuberculosis and non-tuberculous mycobacteria affect the tissues. Although surgical debridement and antibiotic therapy are required for the treatment, it is necessary to identify the causative species before selecting the antibiotics. However, it is difficult to identify the species in clinical samples from musculoskeletal tissue. In the current study, using pathological specimens, the causative species was identified by PCR amplification and direct sequencing of mycobacterial 16S rDNA containing a hypervariable region. Twelve cases of chronic granulomatous inflammation of musculoskeletal tissues were used for the study. DNA was extracted from paraffin sections, and mycobacterial 16S rDNA was amplified by PCR. The amplicons were obtained in 5 of 12 cases (41%), even in specimens in which the microorganism was only scarcely detected by using special stains. Direct sequencing of the amplified products presented high homology with M. tuberculosis in four cases and M. avium in one. Therefore, PCR-direct sequencing of 16S rDNA containing hypervariable region using pathological specimens is useful for the diagnosis and identification of causative species in mycobacterial infection of musculoskeletal tissues.