Stevens-Johnson syndrome and toxic epidermal necrolysis — branching viva

Opening question

Examiner: Take me through this child. What is the diagnosis, and what is your immediate frame? ^[6]

Candidate: This is Stevens-Johnson syndrome-toxic epidermal necrolysis overlap, a severe drug-induced mucocutaneous reaction. The keys are the carbamazepine started six weeks ago, the atypical target lesions, the sheet-like detachment of about 12 percent of body surface area, the positive Nikolsky sign, and the mucositis at two or more sites — the eyes and the mouth. My immediate frame is three things: stop the culprit drug at once, grade the severity with SCORTEN and admit to a burn-capable setting, and involve ophthalmology within hours to protect the eye. ^{[6] [1]}

Examiner: How do you classify this spectrum? ^[1]

Candidate: By the percentage of body-surface-area with epidermal detachment. Stevens-Johnson syndrome is under 10 percent, SJS-TEN overlap is 10 to 30 percent, and toxic epidermal necrolysis is more than 30 percent. All three share atypical target lesions, a positive Nikolsky sign and mucositis at two or more sites. This child, at 12 percent, is in the overlap band. ^[1]