Evaluation of Celiac Disease Prevalence Among Patients with Refractory Hypothyroidism: A Cross-sectional Study

Background: The association of celiac disease (CD) with refractory hypothyroidism is a known but less common condition. Objectives: This study aimed to evaluate the prevalence of CD among patients with refractory hypothyroidism and compare the accuracy of different diagnostic procedures of CD in these patients. Methods: During a six-month period, 25 patients with refractory hypothyroidism were included from the endocrinology outpatient clinics of Ahvaz Jundishapur University of Medical Sciences, Khuzestan, Iran. For all the participants, the serological profile of CD, including anti-tissue transglutaminase (anti-tTG), anti-endomysial antibody (anti-EMA), and total immunoglobulin A, was determined, and then they were referred to undergo upper endoscopy and random biopsies from the first and second parts of the duodenum. Results: The average duration of hypothyroidism among the participants was 7 months. In addition, 75% of the patients (n = 19) were female. The mean age values of male and female subjects were 31.3 ± 17 and 34.3 ± 8.5 years, respectively (age range: 17 - 53 years). The average daily dosage of levothyroxine was 285.1 ± 89.9 mg. The most common comorbidities were anemia (72%) and diarrhea (24%). The most frequent serologic findings in these patients were positive anti-tTG (28%) and anti-EMA (16%). The most common results of upper endoscopy were normal mucosa (48%), gastritis (28%), duodenal fissuring (8%), duodenal atrophy (8%), and duodenal erythema (8%). Based on the results of the pathology report, 20% of the patients (n = 5) were diagnosed with CD (mostly marsh 1 and 0 stages). The sensitivity and specificity of tTG were 33 and 87.5%, respectively. The sensitivity and specificity of EMA were 11.1 and 87.5%, respectively. Conclusions: Based on the results of this pilot study, the prevalence of CD among cases with refractory hypothyroidism is higher than that of global reports. Furthermore, routine screening of CD in these patients is highly recommended even with negative serology. The endoscopic view is not adequate for the diagnosis of CD among patients with refractory hypothyroidism. In addition, it is necessary to focus on pathology reports and antibody titer.