Müge ÖZDEMİR, Atilla SAYGI, Serdar ÖZER, Ebru DAMADOĞLU, Vildan ÇAĞLAYAN, Banu KETENCİ, Öznur AK, Gül DABAK

Comparison of tuberculin skin testing and QuantiFERON-TB Gold-In Tube test in health care workers

Prospektif, kesitsel ve gözlemsel nitelikteki çalışmamızın amacı sağlık çalışanlarında latent tüberküloz infeksiyonu tanısında, tüberkülin cilt testi (TCT) ile QuantiFERON-TB Gold-In Tube (QTF-GIT) testini karşılaştırmaktır. Çalışma, aynı üçüncü basamak göğüs hastalıkları ve tüberküloz eğitim hastanesinde çalışan 78 gönüllü sağlık çalışanını içermektedir. Aktif tüberkülozu, immünyetmezliği ya da malnütrisyonu olanlar çalışmaya dahil edilmemiştir. TCT Mantoux metoduyla uygulandı. ESAT-6, CFP-10 ve TB7-7 antijenleri kanda interferon-gama (IFN-γ) araştırılması için kullanıldı (QTF-GIT). BCG skar sayısı ile TCT endürasyon çapı arasında istatistiksel olarak anlamlı ilişki saptandı (p< 0.01). QTF sonuçları ve önceki BCG aşılaması arasında anlamlı bir ilişki yoktu (p> 0.05). İki test arasında orta düzeyde uyum mevcuttu (κ: 0.346). QTFGIT testinin duyarlılığı %56.14 (TCT ve QTF-GIT pozitif), özgüllüğü %90.48 (TCT ve QTF-GIT negatif), pozitif kestirim değeri %94.12, negatif kestirim değeri %43.18, doğruluk oranı da %65.38 olarak saptandı. QTF sonucuyla TCT endürasyon çapı arasında anlamlı düzeyde ilişki mevcuttu (p< 0.01). QTF-GIT testine göre çalışma popülasyonumuzdaki latent tüberküloz infeksiyon prevalansı %43, TCT’ye göre %73 idi ve BCG aşılanma oranı %87 idi. Sonuç olarak; TCT önceki BCG aşılanmasından etkilenmiş, buna karşın QTF-GIT etkilenmemiştir. Rutin BCG aşılama programı olan toplumlara latent tüberküloz infeksiyonu tanısında TCT’ye alternatif olarak QTF-GIT testini önerebiliriz.

Sağlık çalışanlarında tüberkülin cilt testi ile QuantiFERON-TB Gold-In Tube testinin karşılaştırılması

The purpose of this prospective, cross-sectional observational study was to compare the tuberculin skin testing (TST) with QuantiFERON-TB Gold-In Tube (QTF-GIT) for the detection of latent tuberculosis infection in healthcare workers (HCWs). The study included 78 volunteers who are HCWs at the same tertiary care teaching hospital for chest diseases and tuberculosis. Participants with active tuberculosis, immunodefficiency or malnutrition were not included. The TST was administered by the Mantoux method. Peptides representing ESAT-6, CFP-10 and TB7-7 were used as TB-specific antigens in the whole-blood Interferon-gamma (IFN-γ) assay (QTF-GIT). There was a statistically significant relation between the number of Bacillus Calmette-Guerin (BCG) scars and the diameter of TST (p< 0.01). QTF results according to previous BCG vaccinations did not significantly differ (p> 0.05). There was an intermediate concordance between two tests (κ: 0.346). QTF-GIT has a sensitivity of 56.14% (both TST and QTF-GIT are positive), specificity of 90.48% (both TST and QTF-GIT are negative); positive predictive value of 94.12% and negative predictive value of 43.18% and accuracy is 65.38%. There was a statistically significant relation between TST diameter and QTF result (p< 0.01). Latent tuberculosis infection prevalance of our study population was 43% according to QTF-GIT test, 73% according to TST and BCG vaccination rate was 87%. In conclusion, TST is affected by previous BCG vaccinations, QTF-GIT is not. We can recommend QTF-GIT test for the detection of latent tuberculosis infection as an alternative to TST in populations with routine BCG vaccination programme.

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