TY - JOUR T1 - QFT-GIT vs TST in diagnosis of latent tuberculosis infection (LTBI) in Poland JF - European Respiratory Journal JO - Eur Respir J VL - 38 IS - Suppl 55 SP - p303 AU - Katarzyna Kruczak AU - Marek Sanak AU - Ewa Nizankowska-Mogilnicka Y1 - 2011/09/01 UR - http://erj.ersjournals.com/content/38/Suppl_55/p303.abstract N2 - Introduction: Poland is characterized by medium prevalence of tuberculosis (21,6/100 000) in 2009. The diagnosis of LTBI is difficult due to obligatory multiple revaccination in the past as well as low specificity of tuberculin skin test. So far IGRA tests were rarely done in Poland.Aim: To asses the prevalence of LTBI in the risk groups: 1. homeless, 2. close contacts, 3. casual contacts, 4. nursing home pensioners, 5. random population subjects from Krakow (controls) by QFT-GIT and TST, to compare the agreement and kappa of these tests at 5, 10, 15 mm of TST cut-off and to establish the best TST cut-off for the diagnosis of LTBI.Material and methods: From July 2007 to October 2009 QFT-GIT test was performed in 785 subjects: in group 1 (n = 150); 2 (n = 171); 3 (n = 163); 4 (n = 152); 5 (n = 149) and TST was carried out in: 129, 156, 147, 148 and 121 subjects respectively. In each group the agreement and kappa coefficient between QFT-GIT and TST at 5, 10, 15 mm of TST diameter was analyzed.Results: We observed high prevalence of LTBI in relevant studied groups: 37%, 27%, 25%, 21% and 23% by QFT-GIT and by TST: 56%, 47%, 48%, 43%, 48% respectively. Agreement and kappa at 5, 10, 15 mm of TST cut-off in each group were: in group 1: 58,7% (0,26); 60,7% (0,34); 75,4% (0,45); 2: 55,8% (0,20); 73,0% (0,29); 73,4% (0,32); 3: 53,7% (0,19); 75,0% (0,30); 76,1% (0,40); 4: 64,0% (0,29); 78,8% (0,36); 79,0% (0,45); and in group 5: 55,8% (0,20); 60,9% (0,24); 70,0% (0,23).Conclusions: TST was characterized by lower diagnostic value in Polish population vaccinated and revaccinated with BCG but TST cut-off 15 mm and more should be considered for diagnosis of LTBI bacause of highest agreement with QFT-GIT. ER -