Augustynowicz-Kopeć Ewa, Siemion-Szcześniak Izabela, Zabost Anna, Wyrostkiewicz Dorota, Filipczak Dorota, Oniszh Karina, Gawryluk Dariusz, Radzikowska Elżbieta, Korzybski Damian, Szturmowicz Monika
Department of Microbiology, National Research Institute of Tuberculosis and Lung Diseases , Warsaw , Poland.
The First Department of Lung Diseases, National Research Institute of Tuberculosis and Lung Diseases , Warsaw , Poland.
Pol J Microbiol. 2019;68(1):15-19. doi: 10.21307/pjm-2019-002.
Interferon gamma releasing assays (IGRAs) are extensively used in the diagnosis of latent tuberculosis infections. Comparing to tuberculin skin test (TST) they lack false positive results in the populations vaccinated with BCG, and in most non-tuberculous mycobacteria (NTM) infections. Nevertheless, , and may induce positive IGRAs due to RD1 homology with The aim of the study was to investigate the possible influence of NTM respiratory isolates on the results of IGRAs. 39 patients (23 females and 16 males) of median age 61 years, with negative medical history concerning tuberculosis, entered the study. Identification of NTM was performed using the niacin test and molecular method GenoType CM test (Hain Lifescience). QFT-Plus was performed in 17 patients, T-SPOT-Tb - in 23 patients. Chest X-rays and a high-resolution computed tomography of the chest have been reviewed by the experienced radiologist blinded to the results of IGRAs, in search of past tuberculosis signs. Positive IGRAs results were obtained in three out of 39 patients (8%): 22% of patients with isolates and 18% of patients with radiological signs on HRCT that might be suggestive of past tuberculosis. Positive IGRAs correlated with radiological signs suggestive of past tuberculosis (r = 0.32, = 0.04), and on the borderline with isolation of (r = 0.29, = 0.06). These findings may suggest that a positive IGRAs result, in our material, could depend mostly on asymptomatic past Tb infection. The cross-reactivity of isolates with IGRAs was less probable; nevertheless, it requires further investigations. Interferon gamma releasing assays (IGRAs) are extensively used in the diagnosis of latent tuberculosis infections. Comparing to tuberculin skin test (TST) they lack false positive results in the populations vaccinated with BCG, and in most non-tuberculous mycobacteria (NTM) infections. Nevertheless, , and may induce positive IGRAs due to RD1 homology with The aim of the study was to investigate the possible influence of NTM respiratory isolates on the results of IGRAs. 39 patients (23 females and 16 males) of median age 61 years, with negative medical history concerning tuberculosis, entered the study. Identification of NTM was performed using the niacin test and molecular method GenoType CM test (Hain Lifescience). QFT-Plus was performed in 17 patients, T-SPOT-Tb – in 23 patients. Chest X-rays and a high-resolution computed tomography of the chest have been reviewed by the experienced radiologist blinded to the results of IGRAs, in search of past tuberculosis signs. Positive IGRAs results were obtained in three out of 39 patients (8%): 22% of patients with isolates and 18% of patients with radiological signs on HRCT that might be suggestive of past tuberculosis. Positive IGRAs correlated with radiological signs suggestive of past tuberculosis (r = 0.32, = 0.04), and on the borderline with isolation of (r = 0.29, = 0.06). These findings may suggest that a positive IGRAs result, in our material, could depend mostly on asymptomatic past Tb infection. The cross-reactivity of isolates with IGRAs was less probable; nevertheless, it requires further investigations.
干扰素γ释放试验（IGRAs）广泛应用于潜伏性结核感染的诊断。与结核菌素皮肤试验（TST）相比，它们在接种卡介苗的人群以及大多数非结核分枝杆菌（NTM）感染中没有假阳性结果。然而，[某些特定的NTM]由于与[结核分枝杆菌的RD1区域]具有同源性，可能会诱导IGRAs出现阳性结果。本研究的目的是调查NTM呼吸道分离株对IGRAs结果可能产生的影响。39例患者（23例女性和16例男性）进入研究，年龄中位数为61岁，既往无结核病病史。使用烟酸试验和分子方法GenoType CM试验（海因生命科学公司）对NTM进行鉴定。17例患者进行了QFT-Plus检测，23例患者进行了T-SPOT-Tb检测。一位对IGRAs结果不知情的经验丰富的放射科医生对胸部X线和胸部高分辨率计算机断层扫描进行了复查，以寻找既往结核病的迹象。39例患者中有3例（8%）IGRAs结果呈阳性：分离出[特定NTM]的患者中有22%，HRCT上有可能提示既往结核病的放射学征象的患者中有18%。IGRAs阳性与提示既往结核病的放射学征象相关（r = 0.32，P = 0.04），与[特定NTM]的分离情况接近临界相关（r = 0.29，P = 0.06）。这些发现可能表明，在我们的研究材料中，IGRAs阳性结果可能主要取决于无症状的既往结核感染。[特定NTM]分离株与IGRAs的交叉反应可能性较小；然而，这需要进一步研究。干扰素γ释放试验（IGRAs）广泛应用于潜伏性结核感染的诊断。与结核菌素皮肤试验（TST）相比，它们在接种卡介苗的人群以及大多数非结核分枝杆菌（NTM）感染中没有假阳性结果。然而，[某些特定的NTM]由于与[结核分枝杆菌的RD1区域]具有同源性，可能会诱导IGRAs出现阳性结果。本研究的目的是调查NTM呼吸道分离株对IGRAs结果可能产生的影响。39例患者（23例女性和16例男性）进入研究，年龄中位数为61岁，既往无结核病病史。使用烟酸试验和分子方法GenoType CM试验（海因生命科学公司）对NTM进行鉴定。17例患者进行了QFT-Plus检测，23例患者进行了T-SPOT-Tb检测。一位对IGRAs结果不知情的经验丰富的放射科医生对胸部X线和胸部高分辨率计算机断层扫描进行了复查，以寻找既往结核病的迹象。39例患者中有3例（8%）IGRAs结果呈阳性：分离出[特定NTM]的患者中有22%，HRCT上有有可能提示既往结核病的放射学征象的患者中有18%。IGRAs阳性与提示既往结核病的放射学征象相关（r = 0.32，P = 0.04），与[特定NTM]的分离情况接近临界相关（r = 0.29，P = 0.06）。这些发现可能表明，在我们的研究材料中，IGRAs阳性结果可能主要取决于无症状的既往结核感染。[特定NTM]分离株与IGRAs的交叉反应可能性较小；然而，这需要进一步研究。
