What differentiates erythema multiforme from Stevens-Johnson syndrome?

The distinguishing factor between erythema multiforme and Stevens-Johnson syndrome is indeed related to the severity and extent of mucosal involvement.

Erythema multiforme is typically characterized by target-like lesions and mild systemic symptoms, often with less extensive mucosal involvement. In contrast, Stevens-Johnson syndrome presents with a more severe condition, featuring significant mucosal involvement which can lead to complications and greater morbidity. The mucosal surfaces affected in Stevens-Johnson syndrome can include the eyes, mouth, and genitals, which can result in serious and painful sequelae.

Understanding this distinction is crucial for clinicians as it influences the management and treatment approach. Stevens-Johnson syndrome often requires more aggressive treatment and monitoring due to the risk of severe systemic reactions and complications, whereas erythema multiforme may resolve with supportive care.