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Differential Diagnosis for 6 Month Old with Fever and Oral Ulcerations

Single Most Likely Diagnosis

  • Herpes Simplex Virus (HSV) Infection: This is a common cause of oral ulcerations in infants, often accompanied by fever. The presence of vesicular lesions that rupture to form ulcers is characteristic.

Other Likely Diagnoses

  • Hand, Foot, and Mouth Disease (HFMD): Caused by viruses like Coxsackievirus A, this condition presents with fever, oral ulcers, and a rash on the hands and feet.
  • Oral Thrush: A fungal infection that can cause white patches and ulcers in the mouth, often associated with fever in infants.
  • Trauma or Irritation: Accidental biting of the tongue or cheek, or irritation from a sharp tooth, can cause oral ulcers and may be accompanied by fever if there's a secondary infection.

Do Not Miss Diagnoses

  • Herpangina: Although similar to HFMD, it's crucial to differentiate due to potential complications and the need for specific antiviral treatment in some cases.
  • Bacterial Pharyngitis: Can present with oral ulcers and fever; missing this diagnosis could lead to untreated bacterial infections like streptococcal pharyngitis.
  • Infectious Mononucleosis (Rare in this Age Group): Though uncommon in infants, it can present with fever and oral ulcers, and missing this diagnosis could lead to complications.
  • Autoimmune Disorders (e.g., Pemphigus): Rare but potentially life-threatening conditions that require early diagnosis and treatment.

Rare Diagnoses

  • Erythema Multiforme: An immune-mediated condition that can cause oral ulcers and fever, often in response to an infection or medication.
  • Stevens-Johnson Syndrome: A severe form of skin and mucous membrane disorders, usually a reaction to medication or infection, which can be life-threatening.
  • Behçet's Disease: A rare condition that can cause oral ulcers, among other symptoms, but is extremely uncommon in infants.
  • Leukemia or Lymphoma: Though rare, these conditions can cause oral ulcers and fever due to immunosuppression and should be considered in the differential diagnosis to ensure timely intervention.

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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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