Pacheco Maria Cristina, Fink Susan L, Lee Dale, Dickerson Jane
Department of Laboratories, Seattle Children's Hospital, Seattle, Washington, USA.
Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA.
J Pediatr Gastroenterol Nutr. 2024 Dec;79(6):1164-1171. doi: 10.1002/jpn3.12382. Epub 2024 Oct 3.
Serologic diagnosis using tissue transglutaminase immunoglobulin A (TTG-IgA) and endomysial antibody (EMA) is being integrated into the care of pediatric patients with positive screening for celiac disease. The purpose of this study was to assess the utility of EMA in pediatric patients being considered for serologic diagnosis.
Patients with TTG-IgA testing performed between May 1, 2022 and April 30, 2023 and with subsequent duodenal biopsy within 6 months were included. TTG-IgA serum samples were frozen and sent for EMA testing and titer. EMA was evaluated for positivity and TTG-IgA (normal <15 U/mL) for elevation <10 times (10x) the upper limit of normal (ULN) and ≥10x ULN (≥150 U/mL). Sensitivity and specificity of EMA and TTG-IgA were calculated using biopsy histology as the gold standard.
Four hundred and eighty-six patients were included. The sensitivity and specificity of TTG-IgA ≥15 U/mL was 87.5% and 95.4% while EMA was 77.5% and 97.3%. For patients with TTG-IgA ≥10x ULN the specificity was 99.3%. The positive predictive value of TTG-IgA at ≥10x ULN was 91.4% and for EMA was 83.6%. All three patients with false-positive TTG-IgA ≥10x ULN also had false-positive EMA, and two of these patients had type 1 diabetes mellitus.
TTG-IgA has greater sensitivity at the screening threshold of ≥15 U/mL and greater specificity and positive predictive value at ≥10x ULN than EMA. TTG-IgA at ≥10x ULN is superior to EMA for the serologic diagnosis of celiac disease.
使用组织转谷氨酰胺酶免疫球蛋白A（TTG-IgA）和肌内膜抗体（EMA）进行血清学诊断正被纳入乳糜泻筛查呈阳性的儿科患者的护理中。本研究的目的是评估EMA在考虑进行血清学诊断的儿科患者中的效用。
纳入2022年5月1日至2023年4月30日期间进行TTG-IgA检测且随后在6个月内进行十二指肠活检的患者。TTG-IgA血清样本被冷冻并送去进行EMA检测和滴度测定。评估EMA的阳性情况以及TTG-IgA（正常<15 U/mL）升高至正常上限（ULN）的<10倍（10x）和≥10倍ULN（≥150 U/mL）的情况。以活检组织学作为金标准计算EMA和TTG-IgA的敏感性和特异性。
共纳入486例患者。TTG-IgA≥15 U/mL的敏感性和特异性分别为87.5%和95.4%，而EMA分别为77.5%和97.3%。对于TTG-IgA≥10倍ULN的患者，特异性为99.3%。TTG-IgA≥10倍ULN的阳性预测值为91.4%，EMA为83.6%。所有3例TTG-IgA≥10倍ULN假阳性的患者也有EMA假阳性，其中2例患者患有1型糖尿病。
在筛查阈值≥15 U/mL时，TTG-IgA比EMA具有更高的敏感性，在≥10倍ULN时具有更高的特异性和阳性预测值。TTG-IgA≥10倍ULN在乳糜泻的血清学诊断方面优于EMA。
