Spotlight on celiac disease diagnosis and treatment

Four recent studies focused on the diagnosis and treatment of patients with celiac disease.

The first study, a systematic review and meta-analysis published Jan. 18 by Alimentary Pharmacology and Therapeutics, found that the accuracy of serological tests for detecting celiac disease was high. It included 113 studies with a total of 28,338 patients receiving secondary care. The IgA anti-tissue transglutaminase (tTG) and IgA endomysial antibody tests were the most commonly studied tests in adults, with 27 and 19 studies performed, respectively. Summary sensitivity and specificity of IgA tTG were 90.7% (95% CI, 87.3% to 93.2%) and 87.4% (95% CI, 84.4% to 90.0%), respectively, in five studies. While the sensitivity of IgA endomysial antibodies was slightly lower at 88.0% (95% CI, 75.2% to 94.7%), specificity was higher at 99.6% (95% CI, 92.3% to 100%) in five studies.

Among other limitations, a small proportion of studies were available to contribute to the summary estimates, which could have resulted in decreased accuracy, the authors noted. They added that more research is needed on serological test accuracy in real-world primary care settings where serological tests are used. “With the growing movement towards biopsy-avoidant pathways, the diagnosis and management of coeliac disease is likely to increasingly take place in primary rather than secondary care,” they concluded. “It is therefore key that serological testing strategies are evaluated in primary care populations.”

The second study found that delayed diagnosis in patients with celiac disease is associated with atypical presentation, anemia, worse laboratory parameters, and advanced histology. Researchers conducted a retrospective analysis of prospectively collected clinical and laboratory data from patients with celiac disease ages 12 years and older at a tertiary care center in northern India from January 2015 to December 2018. They divided patients into two groups: those who received an early diagnosis (≤3 years from symptom onset to time of diagnosis) or a delayed diagnosis (>3 years from symptom onset to time of diagnosis). The researchers compared demographic, clinical, laboratory, and histological manifestations between groups. Results were published Jan. 22 by the Indian Journal of Gastroenterology.

Of 570 patients, 289 were in the early diagnosis group and 281 were in the delayed diagnosis group. Those with a delayed diagnosis presented more often with atypical signs and symptoms than those in the early diagnosis group, initially presenting with lower rates of diarrhea with or without weight loss (23.8% vs. 74.4%; P=0.0001) and physician (37.7% vs. 46.4%; P=0.037) and gastroenterologist consultation (26.3% vs. 34.9%; P=0.026) but significantly higher rates of anemia (85.4% vs. 75.1%; P=0.002), pubertal delay (11% vs. 3.5%; P=0.0001), and menstrual irregularities in women (72.5% vs. 26.3%; P<0.0001), as well as higher rates of low hemoglobin, low ferritin, low transferrin saturation, and low vitamin D levels. They also had significantly higher tTG antibody titers and higher grades of villous atrophy at presentation. The study was limited by its retrospective design, among other factors, the authors noted, adding that the findings indicate a need for greater awareness of celiac disease.

While elimination of gluten from the diet is the only available treatment for patients with celiac disease, the other two studies, both small randomized controlled trials, evaluated the addition of other potential treatments. The first found that group-based education helped improve GI symptoms and quality of life compared with routine education. Researchers selected patients ages 18 to 55 years with biopsy-proven disease from a celiac registry database in East Azerbaijan Province, Iran. Of 130 patients (mean age, 37.57 years) who were on a gluten-free diet for at least three months (mean duration, 4.78 years), researchers randomly assigned 66 to receive group-based education in a class of eight to 10 patients and 64 to receive routine individual-based education in the celiac disease clinic for three months. The primary outcomes were GI symptoms and quality of life, assessed using the GI symptom rating scale questionnaire (GSRS) and SF-36 questionnaire, respectively, at baseline and at three months after the intervention. Results were published Jan. 11 by BMC Gastroenterology.

At three months postintervention, the mean total GSRS score in the intervention group was significantly lower compared with the control group (total score, 1.82 vs. 2.07; P=0.04). On the SF-36, mean quality-of-life scores postintervention were significantly higher in the intervention versus control group on the Mental Component Score (59.76 vs. 56.89; P=0.02) but not the Physical Component Score (61.47 vs. 60.23; P=0.1). Among other limitations, the inclusion criteria of the study may limit generalizability of the findings, the authors noted. “Considering the limitations of the study, more studies with longer durations of follow-up and using disease-specific questionnaires, and assessing the patients' subjective feedback about the method of education are needed to prove these results,” they concluded.

The final trial, published Jan. 17 by Clinical Gastroenterology and Hepatology, found that a short-term diet moderately low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) significantly reduced GI symptoms and increased celiac disease-specific health. It enrolled 70 adults with biopsy-proven celiac disease and was performed at a hospital in Norway from October 2018 until August 2019. Inclusion criteria included persistent GI symptoms (defined by GSRS-irritable bowel syndrome [IBS] version score ≥30), gluten-free diet adherence for 12 months or more, and serological and mucosal remission. Researchers randomized participants to adopt a dietician-instructed, moderately low-FODMAP gluten-free diet or to continue their usual gluten-free diet. They recorded GSRS-IBS scores at baseline and weeks one through four and Celiac Symptom Index scores at baseline and week four.

There were 34 participants in the intervention group and 36 in the control group. GSRS-IBS scores were significantly lower in the intervention group versus the control group after one week (mean difference, −8.2; 95% CI, −11.5 to −5.0) and after four weeks (mean difference, −10.8; 95% CI, −14.8 to −6.8). In addition, there were significantly lower scores in the intervention group for the specific measures of pain, bloating, diarrhea, and satiety (P<0.04 for interaction), but not constipation (P=0.43 for interaction). At week four, Celiac Symptom Index scores were significantly lower in the intervention group versus the control group (mean difference, −5.8; 95% CI, −9.6 to −2.0). The study was limited by its nonblinded design and use of habitual diet as the comparator, as patients randomized to the control group may have anticipated that their symptoms would not improve, the authors noted.