Abrams Julian A, Brar Pardeep, Diamond Beverly, Rotterdam Heidrun, Green Peter H
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, New York, USA.
Clin Gastroenterol Hepatol. 2006 Jun;4(6):726-30. doi: 10.1016/j.cgh.2006.02.010. Epub 2006 Apr 19.
BACKGROUND & AIMS: The diagnosis of celiac disease often relies on the anti-tissue transglutaminase (tTG) antibody test. The aim of this study was to evaluate its sensitivity and specificity in clinical practice with the use of commercial laboratories, in which the test characteristics might differ from research laboratories.
We identified 122 patients with suspected celiac disease who had anti-tTG antibody serologies as well as upper endoscopy with duodenal biopsies. Those with celiac disease were classified as either classic (with diarrhea or other symptoms of malabsorption) or silent (asymptomatic). Biopsies from celiac disease patients were classified as either partial (Marsh IIIA) or total (Marsh IIIB or IIIC) villous atrophy.
The overall sensitivity, specificity, and positive and negative predictive values of the anti-tTG antibody test were 70.6%, 65.0%, 91.1%, and 30.2%, respectively. The sensitivity was 90.0% for patients with total villous atrophy and 42.3% for patients with partial villous atrophy (P < .0001). There were differences in both sensitivity and specificity between the 2 most commonly used commercial laboratories. The sensitivity for Lab #1 was 40.0% versus 86.4% for Lab #2 (P < .0001). The specificity for Lab #1 was 100.0%, and it was 41.7% for Lab #2 (P = .02).
The sensitivity of the anti-tTG antibody in clinical practice is not as high as previously reported in research laboratories. The sensitivity is significantly lower in patients with partial villous atrophy. There is also significant variability in test characteristics among major commercial laboratories in the United States. These results need to be confirmed in prospective studies.
乳糜泻的诊断通常依赖抗组织转谷氨酰胺酶（tTG）抗体检测。本研究旨在评估在商业实验室中该检测在临床实践中的敏感性和特异性，商业实验室的检测特性可能与研究实验室不同。
我们确定了122例疑似乳糜泻患者，这些患者进行了抗tTG抗体血清学检测以及十二指肠活检的上消化道内镜检查。患有乳糜泻的患者分为典型（有腹泻或其他吸收不良症状）或隐匿型（无症状）。乳糜泻患者的活检分为部分（马什IIIA型）或完全（马什IIIB型或IIIC型）绒毛萎缩。
抗tTG抗体检测的总体敏感性、特异性、阳性预测值和阴性预测值分别为70.6%、65.0%、91.1%和30.2%。完全绒毛萎缩患者的敏感性为90.0%，部分绒毛萎缩患者的敏感性为42.3%（P <.0001）。两家最常用的商业实验室在敏感性和特异性方面均存在差异。实验室1的敏感性为40.0%，而实验室2为86.4%（P <.0001）。实验室1的特异性为100.0%，实验室2为41.7%（P =.02）。
抗tTG抗体在临床实践中的敏感性不如研究实验室先前报告的高。部分绒毛萎缩患者的敏感性显著较低。美国主要商业实验室的检测特性也存在显著差异。这些结果需要在前瞻性研究中得到证实。
