Differential Diagnosis for Burning Macular Rash that Worsened with Steroids

• Single Most Likely Diagnosis
  • Erythema Multiforme (EM): This condition is characterized by a maculopapular rash that can have a burning sensation. It can be triggered by various factors, including infections and medications. The worsening of symptoms with steroid use is not typical but can occur due to the suppression of the immune system, potentially leading to a rebound effect or uncovering an underlying infection.
• Other Likely Diagnoses
  • Contact Dermatitis: An allergic or irritant reaction to substances coming into contact with the skin, which can cause a burning macular rash. Steroids are often used to treat contact dermatitis, but in some cases, especially with prolonged use or in sensitive individuals, they might exacerbate symptoms or lead to side effects like skin atrophy.
  • Psoriasis: A chronic skin condition that can cause red, scaly patches. While steroids can initially improve psoriasis, their withdrawal or prolonged use can lead to a rebound effect, worsening the condition.
  • Seborrheic Dermatitis: A condition causing scaly patches, red skin, and stubborn dandruff. It can sometimes be exacerbated by the inappropriate use of steroids, leading to a worsening of symptoms.
• Do Not Miss Diagnoses
  • Infections (e.g., Herpes Simplex, Varicella-Zoster): These can present with a rash and may worsen with steroid use due to immunosuppression. Early recognition and antiviral treatment are crucial.
  • Stevens-Johnson Syndrome (SJS) / Toxic Epidermal Necrolysis (TEN): Although rare, these are life-threatening conditions usually triggered by medications or infections. They can present with a burning rash and are medical emergencies.
• Rare Diagnoses
  • Pemphigus: A group of rare skin disorders that cause blistering of the skin and mucous membranes. While steroids are a mainstay of treatment, rare cases might not respond as expected, or there could be a paradoxical worsening due to underlying disease activity or other factors.
  • Dermatomyositis: An inflammatory disease characterized by skin rash and muscle weakness. The rash can be macular and burning, and while steroids are used to treat dermatomyositis, the response can be variable, and disease activity might not always correlate with steroid use.