Differential Diagnosis for SJS and TEN

To differentiate Stevens-Johnson Syndrome (SJS) from Toxic Epidermal Necrolysis (TEN), it's crucial to understand that both conditions are part of the same spectrum of severe skin reactions, often to medications or infections. The primary distinction lies in the extent of skin detachment and the severity of the condition. Here's a differential diagnosis categorized for clarity:

• Single Most Likely Diagnosis

  • Stevens-Johnson Syndrome (SJS) / Toxic Epidermal Necrolysis (TEN) Spectrum: This is the most likely diagnosis when considering a patient with severe skin and mucous membrane lesions, especially if there's a recent history of medication use or infection. The distinction between SJS and TEN is based on the body surface area (BSA) affected, with SJS typically involving less than 10% BSA and TEN involving more than 30% BSA.

• Other Likely Diagnoses

  • Erythema Multiforme (EM): This condition presents with target lesions and can involve mucous membranes but typically lacks the widespread skin detachment seen in SJS/TEN.
  • Staphylococcal Scalded Skin Syndrome (SSSS): Caused by staphylococcal toxins, SSSS presents with widespread skin exfoliation but usually spares the mucous membranes and has a different demographic and clinical presentation.
  • Autoimmune Bullous Diseases (e.g., Pemphigus Vulgaris): These conditions can cause blistering skin lesions and mucous membrane involvement but are distinguished by specific autoantibody profiles and histopathological findings.

• Do Not Miss Diagnoses

  • Severe Burns: The clinical presentation of TEN can mimic severe burns, and it's crucial to differentiate these conditions due to the vastly different management approaches.
  • Infectious Etiologies (e.g., Septicemia, Meningitis): Infections can cause or exacerbate skin lesions and must be promptly identified and treated to prevent fatal outcomes.
  • Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS): Although DRESS syndrome has a different time course and often includes eosinophilia and systemic symptoms, it can sometimes be confused with SJS/TEN, especially in its early stages.

• Rare Diagnoses

  • Paraneoplastic Pemphigus: A rare autoimmune disorder associated with underlying neoplasms, characterized by severe mucous membrane lesions and skin blistering.
  • Graft-Versus-Host Disease (GVHD): In patients with a history of bone marrow or stem cell transplantation, GVHD can cause skin lesions and mucous membrane involvement that might be confused with SJS/TEN.
  • Toxic Shock Syndrome: While primarily known for its systemic symptoms, toxic shock syndrome can cause a rash and skin desquamation, although it is distinct in its pathophysiology and clinical context.