RESUMO
BACKGROUND: The differential diagnosis of ulcerative oral lesions is diverse. This report discusses the rare causes of oral mucosal ulceration and suggests approaches for diagnosis and treatment. METHODS: Two cases of methotrexate-induced stomatitis in patients receiving low dose methotrexate for rheumatoid arthritis are presented with a review of the current literature. In case 1, mucositis was caused by an unintended methotrexate overdose. In case 2, oral lesions were the result of chronic methotrexate toxicity. The treatment for methotrexate-induced mucositis required hospitalization in case 1, methotrexate discontinuation in both cases and oral folic acid supplementation in case 2. RESULTS: In both cases, the mucositis healed and no relapse was observed. CONCLUSION: Mucositis may be an early sign of systemic conditions, and dental providers are often the first doctors involved in the assessment of oral mucosal diseases. Meticulous questioning of the patient's history and the physical examination is important for elucidating the underlying cause.
