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Why does this woman keep getting mouth ulcers?


The patient

This 27-year old woman presented with a large mouth ulcer.

Looking back through her recent visits to the surgery, there had been four similar occasions when she had presented with mouth ulcers.

First instinct

This looked a typical aphthous ulcer, but the frequency of occurrence raised other possibilities.

Differential diagnosis

• Aphthous ulcers: cause unknown, may be bigger than 1cm, can last weeks and are often recurrent

• Infectious mononucleosis


• Inflammatory bowel disease

• Ulcerative colitis

• Crohn's disease

• Coeliac disease

• Rheumatoid diseases, systemic lupus erythematosus and Behcet's syndrome

• Pemphigus and pemphigoid

• Dermatitis herpetiformis

• Malignancy including leukaemia

• Erythema multiforme, including Stevens Johnson syndrome

• Vitamin deficiency, especially vitamin B12 and folate

• Drug misuse

• Stress.

Asking questions

Examination was unremarkable except for the large buccal ulcer.

I asked about other symptoms. She admitted to fatigue but felt this might be because of her demanding job as well as having young children.

I questioned her about genital ulceration and there was no relevant history. She gave no history of joint pains or stiffness.

The hidden clue

She denied any diarrhoea or bleeding from her bowel. But she did say she had previously been diagnosed with irritable bowel syndrome, due to abdominal discomfort and distension.

Getting on the right track

I arranged some blood tests. FBC was normal except for a low MCV. There was no evidence of infection or abnormalities of the white cells. CRP and ESR were normal, hopefully excluding IBD and rheumatic diseases. Liver, renal and thyroid blood tests were normal.

Her ferritin level was low at 16 and her red-cell folate was also low. Her vitamin B12 level was normal.

Her anti-endomysial antibody test was positive, suggestive of coeliac disease.

She was referred to the local gastroenterologist and biopsies revealed the typical changes of coeliac disease. She was started on a gluten-free diet, with iron and folic-acid supplements.

Her mouth ulceration resolved and did not recur. She felt more energetic and her abdominal symptoms all resolved.

Dr Hercules Robinson is a GP in Caithness

Mouth ulcer Mouth ulcer


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