Histologically Confirmed Celiac Disease in a Multifactorial Primary-Care Presentation with Psychiatric,...

Background/Objectives: Celiac disease (CD) is an immune-mediated enteropathy with gastrointestinal and extraintestinal manifestations. In primary care, recognition can be delayed when psychiatric symptoms, arthralgia, thyroid dysfunction, alcohol exposure, and liver-test abnormalities coexist. This case report describes a confounder-aware diagnostic approach to histologically confirmed CD in a patient with a multifactorial primary-care presentation. Methods: We report a single-patient, de-identified reflective case from routine family medicine practice, organized according to CARE case-report principles. Results: A woman in her early sixties with hypothyroidism and glaucoma presented with new low mood, anhedonia, somnolence, generalized anxiety, increased alcohol intake, poor appetite, weight loss, abdominal bloating, diarrhea, flatulence, and polyarthralgia. Initial investigations, including celiac serology obtained before gluten-free diet advice, showed mild anemia, marked hyperferritinemia, severe cholestatic and hepatocellular liver-test abnormalities, uncontrolled hypothyroidism, and strongly positive tissue transglutaminase IgA (>250 kIU/L; reference 0.0-14.9). Radiographs showed mild osteoarthritis and osteopenia without erosive arthropathy. Computed tomography excluded malignancy but showed severe diffuse hepatic steatosis and mild pancreatic atrophy. Mirtazapine was started at the index visit; after the initial laboratory results, gluten-free diet advice, alcohol-reduction counseling, and levothyroxine adjustment were undertaken. During the diagnostic episode, small-bowel biopsy demonstrated moderate-to-severe crypt hyperplastic villous atrophy with increased intraepithelial lymphocytes, and gastric biopsies showed no significant pathology; the histology was consistent with CD. Symptoms improved substantially. Longer-term objective follow-up showed persistent but improved celiac serology (tTG-IgA 49.4 kIU/L), normalization of thyroid-stimulating hormone, partial improvement in gamma-glutamyl transferase, which remained elevated, and a later iron-deficiency pattern with persistent anemia. Conclusions: This case supports targeted CD testing when anxiety or depressive symptoms occur alongside gastrointestinal symptoms, weight loss, arthralgia, hypothyroidism or documented thyroid autoimmunity, anemia, osteopenia, or liver-test abnormalities. Histology and repeat serology confirmed the diagnosis, but the psychiatric and hepatic manifestations still require cautious interpretation because hypothyroidism, alcohol exposure, steatotic liver disease, and simultaneous treatments also shaped the clinical course.