Sachdeva Karan, Kumar Peeyush, Kante Bhaskar, Vuyyuru Sudheer K, Mohta Srikant, Ranjan Mukesh K, Singh Mukesh K, Verma Mahak, Makharia Govind, Kedia Saurabh, Ahuja Vineet
Department of Gastroenterology and Human Nutrition, All India Institute of Medical Sciences, New Delhi, India.
Intest Res. 2023 Apr;21(2):226-234. doi: 10.5217/ir.2022.00010. Epub 2022 Jun 13.
BACKGROUND/AIMS: Intestinal tuberculosis (ITB) and Crohn's disease (CD) frequently present with a diagnostic dilemma because of similar presentation. Interferon-gamma release assay (IGRA) has been used in differentiating ITB from CD, but with sparse reports on its diagnostic accuracy in tuberculosis endemic regions and this study evaluated the same.
Patients with definitive diagnosis of ITB (n=59) or CD (n=49) who underwent IGRA testing (n=307) were retrospectively included at All India Institute of Medical Sciences, New Delhi (July 2014 to September 2021). CD or ITB was diagnosed as per standard criteria. IGRA was considered positive at >0.35 IU/mL. Relevant data was collected and IGRA results were compared between ITB and CD to determine its accuracy.
Among 59 ITB patients (mean age, 32.6±13.1 years; median disease duration, 1 year; male, 59.3%), 24 were positive and 35 tested negative for IGRA. Among 49 CD patients (mean age, 37.8±14.0; median disease duration, 4 years; male, 61.2%), 12 were positive and 37 tested negative for IGRA. Hence, for diagnosing ITB, IGRA showed a sensitivity, specificity, positive and negative predictive values of 40.68%, 75.51%, 66.67%, and 51.39%, respectively. The area under the curve of IGRA for ITB diagnosis was 0.66 (95% confidence interval, 0.55-0.75). In a subset (n=64), tuberculin skin test (TST) showed sensitivity, specificity, positive and negative predictive values of 64.7%, 73.3%, 73.3%, and 64.71%, respectively. IGRA and TST were concordant in 38 (59.4%) patients with κ=0.17.
In a tuberculosis endemic region, IGRA had poor diagnostic accuracy for differentiating ITB from CD, suggesting a limited value of IGRA in this setting.
背景/目的：肠结核（ITB）和克罗恩病（CD）常因临床表现相似而导致诊断困难。干扰素-γ释放试验（IGRA）已用于鉴别ITB和CD，但在结核病流行地区关于其诊断准确性的报道较少，本研究对此进行了评估。
回顾性纳入2014年7月至2021年9月在新德里全印度医学科学研究所确诊为ITB（n=59）或CD（n=49）且接受IGRA检测（n=307）的患者。根据标准标准诊断CD或ITB。IGRA>0.35 IU/mL被视为阳性。收集相关数据，并比较ITB和CD之间的IGRA结果以确定其准确性。
59例ITB患者（平均年龄32.6±13.1岁；疾病持续时间中位数1年；男性占59.3%）中，24例IGRA阳性，35例检测阴性。49例CD患者（平均年龄37.8±14.0岁；疾病持续时间中位数4年；男性占61.2%）中，12例IGRA阳性，37例检测阴性。因此，对于诊断ITB，IGRA的敏感性、特异性、阳性预测值和阴性预测值分别为40.68%、75.51%、66.67%和51.39%。IGRA用于ITB诊断的曲线下面积为0.66（95%置信区间，0.55 - 0.75）。在一个亚组（n = 64）中，结核菌素皮肤试验（TST）的敏感性、特异性、阳性预测值和阴性预测值分别为64.7%、73.3%、73.3%和64.71%。IGRA和TST在38例（59.4%）患者中结果一致，κ值为0.17。
在结核病流行地区，IGRA鉴别ITB和CD的诊断准确性较差，提示在此情况下IGRA价值有限。
