PPD conversion

PPD conversion

Infectious disease The conversion from a state of nonreactivity to reactivity to immune challenge by PPD, presumptive evidence of active TB unless proven otherwise. See Tuberculosis. Cf Anergy.
References in periodicals archive ?
Supporting this perspective are studies associating zip code or area of residence with PPD conversion, rather than specific hospital occupation or specific exposure (9,10).
In some hospitals occupation is significantly associated with risk for PPD conversion.
The classification of risk is based on: 1) the profile of TB in the community, 2) the number of infectious TB patients admitted to the facility area, and 3) analysis of PPD conversion data for the facility's workers.