Differential Diagnosis for Shingles

• Single most likely diagnosis
  • Herpes Zoster (Shingles): This is the most likely diagnosis due to the characteristic rash and pain distribution, typically affecting a single dermatome.
• Other Likely diagnoses
  • Contact Dermatitis: An allergic or irritant reaction to a substance, which could mimic the rash of shingles.
  • Eczema (Atopic Dermatitis): A chronic skin condition that can cause itchy, inflamed skin, potentially resembling shingles.
  • Impetigo: A highly contagious bacterial skin infection that can cause red sores and blisters.
  • Insect Bites: Certain insect bites can cause a rash that might be confused with shingles.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Herpes Simplex Virus (HSV) Infection: Although less common, HSV can cause a similar rash and must be considered, especially in immunocompromised patients.
  • Varicella-Zoster Virus (VZV) Infection in Immunocompromised Patients: In patients with weakened immune systems, VZV can cause more severe and disseminated disease.
  • Erythema Multiforme: A skin condition characterized by target lesions, which can be a sign of a more serious underlying condition.
• Rare diagnoses
  • Ramsay Hunt Syndrome Type 2: A complication of shingles that affects the facial nerve, causing facial paralysis and other symptoms.
  • Zoster Sine Herpete: A condition where the pain of shingles occurs without the characteristic rash.
  • Dermatomal Vesicular Rash caused by other viruses (e.g., Coxsackievirus, Enterovirus): Although rare, other viruses can cause a rash that resembles shingles.