This looks like a really bad burn but it is due to a drug!
The condition is known as toxic epidermal necrolysis where a drug binds to the
skin setting up a type 2 immune reaction where the immune system attacks both the drug and
the epidermal cell it is attached to. The result is full thickness epidermal
necrosis where the epidermis just sloughs off from the underlying dermis.
However equally severe reactions occur on mucosal surfaces with the lips, eyes,
genital and perianal surfaces all eroding and crusting. The skin is very
painful to touch and must be gently handled to prevent further skin sloughing.
Patients are usually managed in a Burns unit where expert care can be given.
Intravenous immunoglobulin and a drug called Rituximab which reduces antibody
production give the best results but death can occur in around 30% of severe
cases. This case was caused by 2 weeks of Sulfonamide for a bladder infection.