Question

The patient came with a history of bullae involving > 30% of the body surface area along with erosions of the lips and other mucosae for the past 7 days. What is the most probable underlying etiology?

• A. Bacterial infection
• B. Viral infection
• C. Drugs
• D. Malignancy

Hint:

Which is the commonest trigger of the SJS-TEN blistering spectrum?

Answer 1

The Correct Option is C

Step 1: Widespread bullae and skin detachment over more than 30% of the body surface area with erosions of the lips and mucosae is the picture of toxic epidermal necrolysis (TEN), the severe end of the Stevens-Johnson syndrome and TEN spectrum.
Step 2: By convention, less than 10% body surface is SJS, more than 30% is TEN, and 10-30% is overlap. The overwhelmingly common underlying cause of SJS and TEN is an adverse drug reaction, classically to anticonvulsants, sulphonamides, allopurinol and NSAIDs.
Step 3: So the most probable etiology is drugs. While Mycoplasma (a bacterial cause) and some viral infections can rarely trigger SJS, especially in children, the single most likely cause of TEN-range disease with greater than 30% involvement is a drug reaction. Malignancy is not a typical trigger of this acute blistering picture.
Ref: Standard dermatology texts on SJS and TEN.