TITLE:
Re-Assessing Tuberculin Skin Test (TST) for the Diagnosis of Tuberculosis (TB) among African Migrants in Western Europe and USA
AUTHORS:
Kebede C. Shero, Mengistu Legesse, Girmay Medhin, Mulugeta Belay, Gunnar Bjune, Fekadu Abebe
KEYWORDS:
Tuberculosis; TST; Diagnosis; IGRA; Migrant; Ethiopia; HIV
JOURNAL NAME:
Journal of Tuberculosis Research,
Vol.2 No.1,
March
21,
2014
ABSTRACT: Background: Tuberculin skin test (TST)—is widely used for screening tuberculosis TB in migrants from high endemic countries of Africa and Asia. However, the cut-off point for clinical TB and Mtb infection is not well established in TB endemic countries of sub-Saharan Africa. In this study we compared the size of TST induration in smear positive pulmonary TB (PTB) patients, their house-hold contacts and community controls in high endemic setting in Ethiopia. Methods: In a health facility-based cross-sectional study, smear positive PTB patients were recruited. Their household contacts traced, and community controls were recruited from neighbourhoods. Sputum sample collected from patients were examined using smear microscopy. Participants were also tested by TST and QuantiFERON? -TB Gold In–Tube test (QFTGIT). Results: From a total of 224 study participants, skin test induration data were available for 48 PTB patients, 88 household contacts and 75 community controls. All 48 patients, 64 (72.2%) of the household contacts and 35 (46.7%) of the community controls had skin test induration ≥ 10 mm. Moreover, 44 (91.7%) PTB patients, 58 (65.9%) of the household contacts and 26 (34.7%) of the community controls had skin test induration ≥ 15 mm, respectively. The mean size of TST induration was significantly higher in TB patients (18.1mm) compared to that of household contacts (13.6 mm) and community controls (7.9 mm) (pMtb infection