What is the cause of persistent oral ulcers (mouth sores)?

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Differential Diagnosis for Painful Sores in Mouth for Months

  • Single most likely diagnosis
    • Aphthous ulcers: These are the most common cause of recurrent, painful mouth sores, and can persist for months if not properly managed.
  • Other Likely diagnoses
    • Oral lichen planus: A chronic inflammatory condition that can cause painful sores and ulcers in the mouth.
    • Oral candidiasis (thrush): A fungal infection that can cause white patches and painful sores in the mouth, especially in immunocompromised individuals.
    • Traumatic ulcers: Sores caused by accidental bites, dental work, or other trauma to the mouth.
  • Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
    • Oral cancer: Although less common, oral cancer can present as a persistent, painful sore in the mouth, and early detection is crucial for effective treatment.
    • HIV/AIDS: Immunocompromised individuals with HIV/AIDS are more susceptible to opportunistic infections, such as oral candidiasis and Kaposi's sarcoma, which can cause painful sores in the mouth.
    • Sjögren's syndrome: An autoimmune disorder that can cause dry mouth and increase the risk of oral infections and sores.
  • Rare diagnoses
    • Pemphigus vulgaris: A rare autoimmune disorder that can cause blistering sores in the mouth and on the skin.
    • Behçet's disease: A rare condition that can cause recurrent, painful mouth sores, as well as other symptoms such as genital sores and eye inflammation.
    • Erythema multiforme: A rare skin condition that can cause painful sores in the mouth, as well as other symptoms such as skin lesions and eye inflammation.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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