Case report: A 15- and a 16-year-old patient presented to Münster University Hospital with persistent oral mucositis, aphthae and mucosal swelling. One of the patients had chronic diarrhoea of unknown origin. An oral mucosal biopsy, an oesophagogastroduodenoscopy and a colonoscopy were performed. The tissue samples taken confirmed the diagnosis of MC of the upper and lower gastrointestinal tract. Systemic therapy was given with the TNF-alpha inhibitor infliximab every 6-8 weeks. The oral mucosa was treated topically with a clobetasol mouth rinse. Both patients experienced a significant decrease in oral symptoms.
Discussion: MC is a dysregulation of the mucosal immune response and can basically occur in any section of the gastrointestinal tract. A discontinuous, granulomatous infestation of the entire intestinal wall with the formation of fistulas, ulcerations, thickenings and stenoses is characteristic. MC is most common in industrialised countries and begins between the ages of 15-30. Lesions of the oral mucosa precede signs in the digestive tract in 10 % of cases.
Besides occasional leukoplakic and lichenoid changes, aphthoid ulcerative lesions of the oral mucosa have been associated with MC. However, mucosal and gingival hyperplasia, mucosal pseudopolyps ("mucosal tags"), lip swelling, and vestibular folds of the so-called "cobblestone pattern" with hyperplasia interrupted by fissures have also been described.
Typically, MC progresses in relapses. In addition to non-specific symptoms, pain and cramps in the lower abdomen as well as diarrhoea may occur. In addition to the clinical course, laboratory and radiological findings, the diagnosis is ultimately made endoscopically and confirmed histologically. The oral biopsy alone is insufficient to establish the diagnosis.
Differential diagnoses include granuloma due to reaction to foreign bodies, infectious diseases, lichen ruber, systemic inflammatory diseases, or leukaemias, which are often distinguished by clinical, microbiological, and/or histopathological symptoms, as well as stomatitis due to malnutrition, sarcoidosis, or Melkersson-Rosenthal syndrome.
In the majority of cases, oral symptoms resolve with treatment of the intestinal disease. Locally applied glucocorticoid therapy is sufficient in 50% of patients, but recurrences are common. In patients with severe impairment, systemic treatment with corticosteroids, TNF-alpha inhibitors (infliximab, adalimumab) or immunosuppressants (azathioprine) are given.
Summary: Unclear mucosal lesions, especially hyperplasia, may be due to Crohn's disease (MC). Sensitisation with regard to the detection of these lesions - sometimes preceding the actual disease - can enable early detection and improve the diagnostic and therapeutic management of the patient.