ulceration of the genital mucous membranes, eye lesions or digestive problems, swollen glands in neck (lymphadenopathy) or a  general unwell feeling.The diagnosis comes mostly from the history and examination, but the following special investigations may be involved: blood tests (vitamin deficiency, anemia, leukemia, Epstein-Barr virus, HIV infection, diabetes) microbiological swabs (infection), or urinalysis (diabetes). A biopsy (minor procedure to cut out a small sample of the ulcer to look at under a microscope) with or without immunofluorescence may be required, to rule out cancer, but also if a systemic disease is suspected. Ulcers caused by local trauma are painful to touch and sore. They usually have an irregular border with erythematous margins and the base is yellow. As healing progresses, a keratotic (thickened, white mucosa) halo may occur. : 52

Differential diagnosis
Due to various factors (saliva, relative thinness of oromucosa, trauma from teeth, chewing, etc. ), vesicles and bullae which form on the mucous membranes of the oral cavity tend to be fragile and quickly break down to leave ulcers. Aphthous stomatitis and local trauma are very common causes of oral ulceration; the many other possible causes are all rare in comparison. Traumatic ulceration
Most mouth ulcers that are not associated with recurrent aphthous stomatitis are caused by local trauma. The mucous membrane lining of the mouth is thinner than the skin, and easily damaged by mechanical, thermal (heat/cold), chemical, or electrical means, or by irradiation.
Páll A, Becs G, Erdei A, Sira L, Czifra A, Barna S, Kovács P, Páll D, Pfliegler G, Paragh G, Szabó Z (2014). "Pseudopheochromocytoma induced by anxiolytic withdrawal". European Journal of Medical Research. 19: 53. doi:10.1186/s40001-014-0053-9. PMC 4196012. PMID 25288254. External links
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