Being in an endemic area, I would routinely screen for Tuberculosis, these days with IGRA (Quantiferon or T-Spot). Recurrent oral ulcers can be a TH1 response to mycobacteria.
Recurrent oral ulcerations may be a feature of Crohn's Disease too. I would check stool calprotectin, stool occult blood, and serum ASCA.
A confluence of positive results, especially if accompanied by gastrointestinal symptoms, warrants further endoscopic and possibly CT scan evaluation for TB or IBD.
There's also intestinal Behçet's. Perhaps Crohn's and Behçet's are overlapping phenotypes of a particular immune response.
www.rheumatologynews.com|By BRUCE JANCIN