Gut and autoimmune disease in the mouth
- Mouth and systemic disease
Crohn and coeliac disease, reflux, bulimia, Sjögren disease, lupus and Behçet disease all leave recognisable marks in the mouth.
What it is
The mouth is the start of the gut and shares immune features with the skin and joints. Crohn disease can cause lip swelling, cobblestoning of the buccal mucosa, linear ulcers in the vestibule and gingival swelling, sometimes before bowel symptoms. Coeliac disease causes symmetrical enamel defects in children and recurrent aphthae. Gastric acid from reflux or bulimia erodes the palatal surfaces of the upper teeth; bulimia also enlarges the parotids. Sjögren disease dries the mouth and eyes and causes cervical caries and candidiasis. Lupus causes painless palatal ulcers and discoid lesions. Behçet disease causes recurrent painful oral ulcers with genital ulcers and uveitis.
Oral findings
- Crohn: lip swelling, cobblestone mucosa, linear vestibular ulcers.
- Coeliac disease: enamel defects, aphthae; may be the only sign.
- Reflux or bulimia: palatal erosion of upper teeth; bulimia also parotid swelling.
- Sjögren disease: dry mouth and eyes, caries at the gum line, candidiasis.
- Lupus: painless palatal ulcers; Behçet disease: recurrent oral and genital ulcers.
What the doctor does
- Recurrent aphthous-like ulcers in an adult with diarrhoea, weight loss or anaemia need gut investigation.
- Approach suspected bulimia with care: dental erosion may be the first observable sign.
- Oral ulcers in lupus are one of the classification criteria and are often painless.
Next step / Initial management
- Orofacial granulomatosis or suspected Crohn disease: blood count, inflammatory markers, faecal calprotectin, and referral to gastroenterology.
- Enamel defects or aphthae with growth or gut symptoms: coeliac serology.
- Dry mouth and eyes: autoantibodies and referral to rheumatology; recurrent oral and genital ulcers: refer to rheumatology and ophthalmology.
- Dental erosion: assess reflux and eating disorders; refer to the dentist for protection of the teeth.
Test yourself
Think of the answer, then tap the question to see it.
Which oral signs suggest Crohn disease?
Lip swelling, cobblestoning of the buccal mucosa, linear vestibular ulcers and gingival swelling.
Which dental finding can suggest coeliac disease in a child?
Symmetrical enamel defects, with or without recurrent aphthous ulcers.
Which oral ulcers are typical of lupus?
Usually painless ulcers on the hard palate.
Connections
Educational content; it does not replace assessment by a dentist or doctor and is not a clinical instruction. For facial or neck swelling with difficulty swallowing or breathing, a knocked-out tooth or bleeding that will not stop, go to an emergency department at once.
Sources: Crohn Disease (StatPearls Publishing (NCBI Bookshelf), 2025); Celiac Disease (StatPearls Publishing (NCBI Bookshelf), 2026); Sjogren Disease (StatPearls Publishing (NCBI Bookshelf), 2025); Behcet Disease (StatPearls Publishing (NCBI Bookshelf), 2026); Bulimia (MedlinePlus, US National Library of Medicine, 2026).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.