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 ?
Latent TB incidence among SA medical students was measured by tuberculin skin test conversion at 23 cases/100 person-years.
Tuberculin Skin Test conversion and reactivity rates among adults with and without Human Immunodeficiency Virus in urban settings in Ethiopia.
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.
paragraph]) Tuberculin skin test conversion is defined by a change from a negative to a positive result and a [greater than or equal to] 10 mm increase in induration, within a 2-year interval (2).
The modified intention-to-treat analysis included 7,731 participants aged [greater than or equal to] 2 years who had LTBI: 5,466 close contacts, 1,925 patients with tuberculin skin test conversions, 179 participants with radiographic findings of healed pulmonary TB, and 161 HIV-infected participants not taking antiretroviral drugs.
Tuberculin skin test conversion in hospital employees vaccinated with bacille Calmette-Guerin: recent Mycobacterium tuberculosis infection or booster effect?
Assessing tuberculin skin test conversion after exposure to tuberculosis on airplanes [Abstract].
Of these, 106 (72%) entered the state prison system with a negative TST and had skin test conversions while in the state prison system; for 97 of the 106, skin test conversion occurred within the previous 2 years.
Before investigations began, 8 mm would have been classified as a negative result; however, in the context of three other positive tuberculin skin test conversions (>10 mm) among nurses on the same unit, an 8 mm induration in a nurse with a 0 mm TST result upon hire the previous year was considered positive.
Since 1993, the rate of TB skin test conversions (which indicate transmission of new infection) of staff has decreased from 1.