[Detection of mycobacterium bovis BCG Tokyo in sputum from a tuberculosis patient and administrative action in public health].

PURPOSE

We encountered a tuberculosis patient with the BCG strain in his sputum. Based on this experience, we investigated ideal surveillance and quality assurance for bacteriological examination as well as cooperation between medical organizations and public administrative organizations such as public health centers for prompt and appropriate measures against tuberculosis.

METHODS

Acid-fast bacilli isolated in the laboratory of a hospital were analyzed by restriction fragment length polymorphism (RFLP) and molecular epidemiological data for pathogen were provided to the public health center in charge.

RESULTS

DNA of acid-fast bacilli isolated from sputum of a tuberculosis patient showed a BCG like pattern on RFLP analysis using two IS6110 and PGRS (polymorphic GC-rich sequence) probes. Additional investigation revealed that the patient had been treated with BCG immuno-therapy against bladder cancer. Accordingly, it was suggested that this was the origin of the BCG strain in the sputum. Therefore, the patient was re-examined clinically, and further contact tracing by the public health center was stopped.

CONCLUSIONS

This study indicates that adequate surveillance and quality assurance in bacteriological examination as well as effective exchange of information between medical organization and public health centers are very important for prompt and appropriate measures against tuberculosis. Further, it provided strong support for identification of pathogens of the molecular level by RFLP analysis.