BACKGROUND: False-positive tuberculin skin test (TST) results due to prior bacille Calmette-Guérin (BCG) vaccination may lead to unnecessary treatment of presumed latent tuberculosis infection (LTBI). Recently approved interferon-gamma release assays (IGRAs) are more specific for LTBI in this group. METHODS: A total of 316 BCG-vaccinated foreign-born individuals with a positive TST had a commercially available IGRA (QuantiFERON®-TB Gold In-Tube) performed as part of a two-step procedure to determine the need for isoniazid therapy. Baseline demographic information and TST size were recorded and analyzed for characteristics associated with an increased likelihood of having a positive IGRA. RESULTS: Increasing age, male sex, origin from a country with a high prevalence of tuberculosis (TB), shorter time since arrival in the United States, and increasing TST size were all independently associated with a positive IGRA. CONCLUSION: Patient characteristics and TST size can help determine those at highest risk for LTBI. A two-step procedure for LTBI screening should be considered for foreign-born persons with prior BCG vaccination and a positive TST.
BACKGROUND: False-positive tuberculin skin test (TST) results due to prior bacille Calmette-Guérin (BCG) vaccination may lead to unnecessary treatment of presumed latent tuberculosis infection (LTBI). Recently approved interferon-gamma release assays (IGRAs) are more specific for LTBI in this group. METHODS: A total of 316 BCG-vaccinated foreign-born individuals with a positive TST had a commercially available IGRA (QuantiFERON®-TB Gold In-Tube) performed as part of a two-step procedure to determine the need for isoniazid therapy. Baseline demographic information and TST size were recorded and analyzed for characteristics associated with an increased likelihood of having a positive IGRA. RESULTS: Increasing age, male sex, origin from a country with a high prevalence of tuberculosis (TB), shorter time since arrival in the United States, and increasing TST size were all independently associated with a positive IGRA. CONCLUSION:Patient characteristics and TST size can help determine those at highest risk for LTBI. A two-step procedure for LTBI screening should be considered for foreign-born persons with prior BCG vaccination and a positive TST.
Authors: M E Castellanos; S Kirimunda; L Martinez; T Quach; H Woldu; R Kakaire; A Handel; S Zalwango; N Kiwanuka; C C Whalen Journal: Int J Tuberc Lung Dis Date: 2018-09-01 Impact factor: 2.373
Authors: Roi Piñeiro; María José Mellado; María José Cilleruelo; Marta García-Ascaso; Antonio Medina-Claros; Milagros García-Hortelano Journal: Eur J Pediatr Date: 2012-07-01 Impact factor: 3.183
Authors: R Ragonnet; J M Trauer; E S McBryde; R M G J Houben; J T Denholm; A Handel; T Sumner Journal: Int J Tuberc Lung Dis Date: 2017-01-01 Impact factor: 2.373