Differential Diagnosis for TEN and SJS
When differentiating between Toxic Epidermal Necrolysis (TEN) and Stevens-Johnson Syndrome (SJS), it's crucial to consider the clinical presentation, history, and potential causes. Here's a structured approach to the differential diagnosis:
- Single Most Likely Diagnosis:
- SJS: This is often considered when there's a skin detachment of less than 10% of the body surface area, along with mucosal involvement. SJS typically has a more gradual onset and is often associated with a recent infection or medication use.
- Other Likely Diagnoses:
- TEN: Characterized by skin detachment of more than 30% of the body surface area, TEN is a more severe condition with a higher mortality rate. It's also associated with medication use, particularly within the first 8 weeks of starting a new drug.
- Erythema Multiforme (EM): Although less severe than SJS/TEN, EM can present with similar skin lesions but typically lacks the widespread skin detachment and mucosal involvement seen in SJS/TEN.
- Do Not Miss Diagnoses:
- Staphylococcal Scalded Skin Syndrome (SSSS): Caused by staphylococcal toxins, SSSS can mimic TEN but typically occurs in children and has a more rapid onset. Missing this diagnosis could lead to inappropriate treatment and increased morbidity.
- Autoimmune Disorders (e.g., Pemphigus Vulgaris): These conditions can cause blistering skin lesions and mucosal involvement, similar to SJS/TEN. Accurate diagnosis is critical for appropriate treatment.
- Rare Diagnoses:
- Paraneoplastic Pemphigus: A rare autoimmune disorder associated with underlying neoplasms, characterized by severe mucosal involvement 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 mucosal involvement similar to SJS/TEN.
Each of these diagnoses requires careful consideration of the patient's history, physical examination, and laboratory findings to ensure accurate diagnosis and appropriate management.