What is the cause of an oral mucosal ulcer (mouth sore) in a pediatric patient?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: March 13, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Differential Diagnosis for Sore on the Wall of the Mouth in Children

  • Single Most Likely Diagnosis
    • Traumatic ulcer (e.g., from biting the cheek or mouth): This is the most common cause of mouth sores in children, often resulting from accidental bites during eating or speaking.
  • Other Likely Diagnoses
    • Aphthous ulcers (canker sores): These are common, recurrent, and often painful ulcers that can appear on the mucous membranes of the mouth, including the walls.
    • Herpes simplex virus (HSV) infection: Primary HSV infection can cause multiple painful ulcers on the gums, tongue, and inside the mouth, including the walls.
    • Hand, foot, and mouth disease (HFMD): A viral illness that can cause sores in the mouth, including on the walls, along with a rash on the hands and feet.
  • Do Not Miss Diagnoses
    • Oral cancer: Although extremely rare in children, any persistent or unusual sore should be evaluated to rule out malignancy.
    • Infectious mononucleosis (mono): Caused by Epstein-Barr virus, it can lead to oral ulcers and other systemic symptoms.
    • Autoimmune disorders (e.g., pemphigus, pemphigoid): These conditions can cause blistering and ulcers in the mouth, including on the walls, and require prompt diagnosis and treatment.
  • Rare Diagnoses
    • Erythema multiforme: A skin condition that can also affect the mucous membranes, causing ulcers and other lesions in the mouth.
    • Stevens-Johnson syndrome: A severe form of skin and mucous membrane disorder, usually a reaction to medication or infection, which can cause oral ulcers among other symptoms.
    • Behçet's disease: A rare disorder that causes blood vessel inflammation throughout the body and can lead to oral ulcers, among 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.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.