Annals of internal medicine
-
Randomized Controlled Trial Clinical Trial
Persistence and boosting of bacille Calmette-Guérin-induced delayed-type hypersensitivity.
Bacille Calmette-Guérin (BCG) vaccination may induce persistent and booster purified protein derivative (PPD) responses that complicate tuberculosis screening efforts. ⋯ Previous BCG vaccination reduces the predictive value of serial PPD testing. The lowest PPD predictive values will occur in persons without known tuberculosis exposure who were vaccinated recently or many times with intradermal BCG. In addition, BCG-related persistence and boosting of delayed-type hypersensitivity responses correlate with other potential surrogate markers of protective mycobacterial immunity.