What causes recurrent oral ulcers (mouth sores) in an adolescent?

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Differential Diagnosis for Recurrent Mouth Sores in a Teenager

  • Single most likely diagnosis:
    • Aphthous ulcers (canker sores): These are the most common cause of recurrent mouth sores, often triggered by stress, minor mouth injury, or certain foods. They are typically self-limiting and can be managed with over-the-counter treatments.
  • Other Likely diagnoses:
    • Herpes simplex virus (HSV) infection: HSV can cause recurrent mouth sores, particularly on the lips (cold sores) or inside the mouth. The virus remains dormant in the nerve cells and can reactivate, leading to recurrent episodes.
    • Trauma or irritation: Accidental bites, dental work, or sharp edges on teeth or dental appliances can cause mouth sores.
    • Nutritional deficiencies: Deficiencies in vitamins such as B12, iron, or folate can lead to mouth sores and other oral health issues.
    • Allergic reactions or sensitivities: Allergies to certain foods, toothpaste, or mouthwashes can cause mouth sores.
  • Do Not Miss diagnoses:
    • Infectious mononucleosis (mono): Caused by the Epstein-Barr virus, mono can lead to mouth sores, fever, and lymphadenopathy. Although not typically deadly, it can lead to significant morbidity if not properly managed.
    • HIV infection: Oral ulcers can be an early sign of HIV infection, making it crucial for diagnosis to prevent long-term complications and transmission.
    • Leukemia or lymphoma: Although rare, these cancers can cause recurrent mouth sores among other systemic symptoms. Early detection is critical for effective treatment.
  • Rare diagnoses:
    • Behçet's disease: A rare autoimmune disorder characterized by recurrent mouth sores, genital ulcers, and eye inflammation.
    • Pemphigus vulgaris: An autoimmune disease causing blistering of the skin and mucous membranes, including the mouth.
    • Erythema multiforme: A skin condition that can also affect the mucous membranes, leading to mouth sores, often in response to infections or medications.
    • Autoimmune disorders like lupus or Crohn's disease: These conditions can sometimes manifest with oral ulcers among a wide range of other symptoms.

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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