What percentage of body surface area (BSA) sloughing defines SJS?

The definition of Stevens-Johnson Syndrome (SJS) is a condition characterized by a severe mucocutaneous reaction, which typically involves sloughing of the skin and mucous membranes. SJS is distinguished from Toxic Epidermal Necrolysis (TEN) based on the percentage of body surface area (BSA) affected.

SJS is defined as a skin reaction where less than 10% of the body’s surface area is affected. This low percentage reflects the more limited extent of skin involvement compared to TEN, which is characterized by more than 30% of BSA involvement. This distinction is crucial because it helps guide treatment and management of the condition, influencing decisions around hospital admission, potential intensive care needs, and specific therapeutic interventions.

Since the question asks for the percentage of BSA sloughing that defines SJS, the correct answer aligns with the established medical criteria that classify SJS when there is sloughing of less than 10% of BSA.