Vesiculobullous Disorders MCQs

Dermatology · 6 free questions with answers & explanations.

1. A 55-year-old woman presents with flaccid blisters that rupture easily leaving raw, painful erosions on her trunk and oral mucosa. Nikolsky sign is positive. Direct immunofluorescence (DIF) of perilesional skin shows IgG and C3 deposits in a fishnet/chicken-wire pattern throughout the epidermis. What is the target antigen?
2. A 70-year-old man presents with tense, intact blisters arising on urticarial plaques on the flexural areas and abdomen. Oral mucosa is spared. Nikolsky sign is negative. DIF shows linear IgG and C3 deposition at the dermo-epidermal junction. On electron microscopy, immune deposits are found in the lamina lucida. The drug most commonly implicated in triggering a drug-induced form of this condition is:
3. A 25-year-old pregnant woman in her second trimester develops intensely pruritic urticarial papules and plaques in the periumbilical area, sparing the umbilicus, and subsequently vesicles on the abdomen. DIF of perilesional skin shows linear C3 ± IgG at the dermo-epidermal junction. What is the diagnosis and the fetal risk?
4. A 35-year-old male presents with intensely pruritic grouped vesicles symmetrically distributed over the extensor surfaces of elbows, knees, scalp, and buttocks. He also reports intermittent diarrhoea and bloating. Small bowel biopsy shows subtotal villous atrophy. DIF of uninvolved perilesional skin shows granular IgA deposits in the dermal papillae. What is the drug of choice?
5. A 10-year-old child presents with large, flaccid bullae on normal-appearing skin, predominantly on the face, neck, and upper trunk. There is no mucosal involvement. Nikolsky sign is positive. Histopathology reveals acantholysis within the granular layer of the epidermis. The autoantigen targeted is:
6. A 40-year-old woman on long-term chloroquine for discoid lupus develops bullous lesions on sun-exposed areas with milia formation and scarring. Urine turns pink-red after sun exposure. Biochemical testing confirms elevated urinary and plasma porphyrins. This drug-induced condition mimics which primary blistering disorder?