No-biopsy approach can diagnose celiac disease in select adults

IgA anti-tissue transglutaminase levels of at least 10 times the upper limit of normal have a sensitivity of 51% and specificity of 100% for predicting celiac disease in adults referred to secondary care, a meta-analysis found.

Certain adult patients could be diagnosed with celiac disease without undergoing an endoscopy and duodenal biopsy, new results of a systematic review and meta-analysis suggest.

Researchers assessed the no-biopsy approach in adults with suspected celiac disease by searching MEDLINE, EMBASE, Cochrane Library, and Web of Science for relevant studies published between January 1998 and October 2023. Eighteen studies with 12,103 participants from 15 countries were included. All eligible studies compared the sensitivity and specificity of IgA anti-tissue transglutaminase (tTg) antibody levels at least 10 times the upper limit of normal (ULN) with duodenal biopsies in adult patients. Findings were published by Gastroenterology on Jan. 2.

The pooled prevalence of biopsy-proven celiac disease was 62% (95% CI, 40% to 83%) for all patients. Thirty-two percent of patients had IgA-tTG levels of at least 10 times the ULN (95% CI, 24% to 40%); the summary sensitivity of this measure was 51% (95% CI, 42% to 60%), and the summary specificity was 100% (95% CI, 98% to 100%). Area under the summary receiver-operating characteristic curve was 0.83 (95% CI, 0.77 to 0.89). In addition, if celiac disease prevalence was 1%, 4%, 10%, and 40% in the population, the positive predictive value (PPV) of the no-biopsy approach to identify patients with the disease was 65%, 88%, 95%, and 99%, respectively. Included studies had moderate between-study heterogeneity, and only one had a low risk of bias across all domains measured. The researchers' findings did not significantly change when they conducted additional sensitivity analyses.

Because all included studies were conducted in secondary and tertiary care settings, results may not be generalizable to primary care, the researchers cautioned. Most of the included studies were also carried out in Europe, limiting generalizability.

Going forward, the decision to avoid endoscopy should be made on a case-by-case basis and take a patient's age, comorbidities, risk factors, and preferences into account, the authors said, adding that “a close collaboration and dialogue between primary and secondary care is necessary to implement the no-biopsy approach safely, and to promote adherence to the serology-biopsy guidelines.”

Overall, the results show the no-biopsy approach can be safely used in select adult patients in secondary care settings and could shorten the time to diagnosis, increase patient satisfaction, and reduce health care costs, the authors concluded.