Using of T-Spot.TB and Mantoux tests in diagnosis of M. tuberculosis infection in BCG vaccinated children aged five and younger

Infection with M. tuberculosis (MT) is difficult to diagnose in young BCG (Bacillus Calmette-Guérin) vaccinated children using Mantoux test alone, as a positive test result may be due to infection with MT and previous BCG vaccination. We aimed to test the T-SPOT. TB test for BCG-vaccinated children aged five and younger in two groups - with or without contact with an active tuberculosis (ATB) patient. Prospectively a study group of 121 children (having contact with ATB patient) and a control group of 64 children (without known contact with ATB patient) were examined using Mantoux and T-SPOT. TB tests. The T-SPOT. TB test was positive in 66 (54.5%) study group children and in 2 (3.1%) control group children (P < 0.01). Induration in the Mantoux test ≥ 10 mm was observed in 62 (91.0%) of 68 T-SPOT. TB positive children, and 34 (29.1%) of 117 T-SPOT. TB negative children (P < 0.01). In the group with a negative T-SPOT. TB result boosting of the Mantoux test was observed in 21 (66%) of 32 children who had received repeated Mantoux testing before being included in the study. According to the results, the application of the T-SPOT. TB test is reasonable for primary contact children evaluation and follow-up contact children for whom primary tests did not confirm infection with MT.