skin test conversion

skin test conversion

A change in skin test reaction status—usually understood to mean a change in PPD reactivity—from negative to positive between screening intervals.

skin test conversion

Immunology A change in skin test reaction status–often PPD reactivity–from negative to positive between screening intervals. See Anergy, PPD, Seroconversion, Tuberculosis.
References in periodicals archive ?
Risk of house staff tuberculin skin test conversion in an area with a high incidence of tuberculosis.
3) Repeat skin testing is recommended 3 months after last exposure, since skin test conversion may occur up to 10 weeks after exposure.
Of the contacts, 1,385 (61%) had negative tuberculin skin tests, 232 (10%) had a history of previous TB or positive tuberculin skin test, 23 (1%) had active TB, and 630 (28%) had newly documented positive TB skin tests (121 with skin test conversion and 509 with positive skin tests and no previous test result) and no evidence of active disease.
The proportion of contacts documented to have initiated treatment of latent TB infection did not differ significantly by study area, skin test conversion status, age group, birthplace, contact type, or case smear status, but increased with increasing skin test induration.
Current CDC guidelines state that treatment of latent TB infection should be considered for all infected contacts of TB cases, regardless of birthplace, age, previous BCG vaccine administration, skin test conversion, or other factors.
Indeed, fewer than one half of contacts with skin test conversions and fewer than two thirds of those less than 15 years of age--groups with a high probability of recent infection, and thus at high risk for progression to TB disease--had written documentation that therapy was completed.
Tuberculin skin test conversion in hospital employees vaccinated with bacille Calmette-Guerin: recent Mycobacterium tuberculosis infection or booster effect?
Since 1993, the rate of TB skin test conversions (which indicate transmission of new infection) of staff has decreased from 1.