Vassilopoulos Dimitrios, Tsikrika Stamatoula, Hatzara Chrisoula, Podia Varvara, Kandili Anna, Stamoulis Nikolaos, Hadziyannis Emilia
2nd Department of Medicine, Hippokration General Hospital, Athens University School of Medicine, Athens, Greece.
Clin Vaccine Immunol. 2011 Dec;18(12):2102-8. doi: 10.1128/CVI.05299-11. Epub 2011 Oct 12.
Gamma interferon release assays (IGRAs) are increasingly used for latent Mycobacterium tuberculosis infection (LTBI) screening in patients with rheumatic diseases starting anti-tumor necrosis factor (anti-TNF) therapies. We compared the performances of two IGRAs, an enzyme-linked immunospot release assay (T-SPOT.TB) and an enzyme-linked immunosorbent assay (QuantiFERON-TB Gold In Tube [QFT-GIT]), to that of tuberculin skin testing (TST) for LTBI screening of 157 consecutive rheumatic patients starting anti-TNF therapies. Among 155 patients with valid results, 58 (37%) were positive by TST, 39 (25%) by T-SPOT.TB assay, and 32 (21%) by QFT-GIT assay. IGRAs were associated more strongly with at least one risk factor for tuberculosis (TB) than TST. Risk factors for a positive assay included chest X-ray findings of old TB (TST), advanced age (both IGRAs), origin from a country with a high TB prevalence, and a positive TST (T-SPOT.TB assay). Steroid use was negatively associated with a positive QFT-GIT assay. The agreement rate between IGRAs was 81% (kappa rate = 0.47), which was much higher than that observed between an IGRA and TST. If positivity by either TST or an IGRA was required for LTBI diagnosis, then the rate of LTBI would have been 46 to 47%, while if an IGRA was performed only for TST-positive patients, the respective rate would have been 11 to 17%. In conclusion, IGRAs appear to correlate better with TB risk than TST and should be included in TB screening of patients starting anti-TNF therapies. In view of the high risk of TB in these patients, a combination of one IGRA and TST is probably more appropriate for LTBI diagnosis.
γ-干扰素释放试验（IGRAs）越来越多地用于对开始接受抗肿瘤坏死因子（抗TNF）治疗的风湿性疾病患者进行潜伏性结核分枝杆菌感染（LTBI）筛查。我们比较了两种IGRAs，即酶联免疫斑点释放试验（T-SPOT.TB）和酶联免疫吸附试验（管内定量γ-干扰素释放试验[QFT-GIT]）与结核菌素皮肤试验（TST）对157例连续开始接受抗TNF治疗的风湿性患者进行LTBI筛查的性能。在155例结果有效的患者中，TST阳性58例（37%），T-SPOT.TB试验阳性39例（25%），QFT-GIT试验阳性32例（21%）。与TST相比，IGRAs与至少一种结核病（TB）危险因素的关联更强。检测结果为阳性的危险因素包括陈旧性TB的胸部X线表现（TST）、高龄（两种IGRAs）、来自TB高流行国家以及TST阳性（T-SPOT.TB试验）。使用类固醇与QFT-GIT试验阳性呈负相关。两种IGRAs之间的一致率为81%（kappa值=0.47），远高于IGRA与TST之间的一致率。如果LTBI诊断需要TST或IGRA阳性，则LTBI的发生率为46%至47%，而如果仅对TST阳性患者进行IGRA检测，则相应发生率为11%至17%。总之，IGRAs似乎比TST与TB风险的相关性更好，应纳入开始接受抗TNF治疗患者的TB筛查。鉴于这些患者TB风险高，一种IGRA和TST联合使用可能更适合LTBI诊断。
