Article in Japanese

A pitfall of the nucleic acid amplification test in infants after Bacille Calmette-Gué rin vaccination

Fumihiro OCHI^1,2), Hisamichi TAUCH¹⁾, Eiichi ISHII¹⁾

[Introduction] The nucleic acid amplification test (NAAT) is used to confirm the infection of Mycobacterium tuberculosis in infants. A 3-month-old infant had redness and small pustules at the inoculation site of a BCG vaccination at day 3. Tuberculin reaction was negative, whereas NAAT using gastric aspirates proved positive. This study aimed to examine whether NAAT of gastric or oral aspirates could become positive in infants after Bacille Calmette-Gué rin (BCG) vaccination.
[Materials and method] NAAT was performed by using the oral mucosa wiping fluid of seven infants after BCG vaccination.
[Results] The oral aspirates of three infants showed positive NAAT at day 0 or 2 but became negative thereafter.
[Discussion] It is possible that the NAAT on gastric or oral aspirates could become positive in infants after BCG vaccination, because M. bovis in BCG solutions could be transferred to the oral cavity via the hands of the mother or infant. Careful interpretation of positive NAAT results using gastric aspirates of infants with the Koch phenomenon is required.

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1) Department of Pediatrics, Ehime University Graduate School of Medicine
2) Department of Pediatrics, Yawatahama City General Hospital

Key words	infants, nucleic acid amplification test, tuberculosis, Bacille Calmette-Guérin vaccination, Mycobacterium bovis
Received	May 25, 2017
Accepted	August 4, 2017

29 (4)：311─315,2018