Evaluation of Tuberculin Skin Test Positivity and Early Tuberculin Conversion among Medical Intern Trainees in Tunisia

BACKGROUND: As healthcare workers (HCWs), medical trainees are at a high-risk for acquisition of tuberculosis (TB) infection and disease. To our knowledge, there are no published data about TB infection among medical trainees in Tunisia. To determine the tuberculin skin test (TST) positivity and tuberculin conversion among a group of medical trainees in different departments at our institution. MATERIALS AND METHODS: We performed a prospective study using the TST. The study was conducted in two steps: 1) an initial TST survey and 2) an evaluation of the TST conversion rates. RESULTS: Among 114 participants, the TST was positive (≥10 mm) in 26.3% and negative (<5 mm) in 57%. The conversion rate of TST was 4%, which was only observed among the trainees assigned to the pulmonary departments. The significant predictor variables of TST positivity were a history of nosocomial TB exposure and training in a high-risk area. CONCLUSION: Despite the small number of participants, the high TB conversion rate among the trainees is alarming. This population represents an important target group for a latent tuberculosis infection screening program in countries with limited resources such as Tunisia.