Differential Diagnosis for Pediatric Illnesses with Mouth Alterations

The following differential diagnosis is organized into categories to help guide the thought process:

• Single Most Likely Diagnosis
  • Hand, Foot, and Mouth Disease (HFMD): This is a common viral illness in children, characterized by sores in the mouth and a rash on the hands and feet. The diagnosis is often made clinically based on the presentation of symptoms.
• Other Likely Diagnoses
  • Herpetic Gingivostomatitis: Caused by the herpes simplex virus, this condition leads to painful sores in the mouth and gums, often accompanied by fever and irritability.
  • Aphthous Ulcers: Also known as canker sores, these are small, painful ulcers that can appear in the mouth, though their cause is not always clear.
  • Thrush: A fungal infection that causes white patches in the mouth, which can be painful and may bleed if scraped.
• Do Not Miss Diagnoses
  • Oral Cancer: Although rare in children, any persistent or unusual oral lesions should be thoroughly investigated to rule out malignancy.
  • Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis (SJS/TEN): A severe skin and mucous membrane disorder, usually a reaction to medication or infection, which can present with oral lesions among other symptoms. It's critical to identify and treat promptly due to its high morbidity and mortality.
  • Kawasaki Disease: An acute febrile illness that can present with oral changes such as strawberry tongue, along with other systemic symptoms. Early diagnosis is crucial to prevent cardiac complications.
• Rare Diagnoses
  • Erythema Multiforme: An immune-mediated condition that can cause oral lesions, among other skin and mucous membrane manifestations, often in response to infections or medications.
  • Pemphigus Vulgaris: A rare autoimmune disease causing blistering of the skin and mucous membranes, which can include the mouth.
  • Autoimmune Disorders (e.g., Lupus, Rheumatoid Arthritis): These can occasionally present with oral manifestations, including ulcers or other mucosal changes, in pediatric patients.

Each diagnosis is considered based on the combination of clinical presentation, patient history, and the potential consequences of missing a particular diagnosis. The categorization helps in prioritizing the most likely and critical conditions to investigate first.