General MCQ Flashcards

Which is the most appropriate first-line treatment for uncomplicated cutaneous larva migrans?

Answer: Ivermectin or albendazole

Cutaneous larva migrans, caused by hookworm larvae, is treated with oral ivermectin or albendazole.

A patient on a new sulfa drug develops a well-demarcated round violaceous plaque that recurs at the same site with rechallenge. What is the diagnosis?

Answer: Fixed drug eruption

A fixed drug eruption recurs at the identical location with each exposure to the offending drug.

Which finding is most specific for scabies infestation on dermoscopy?

Answer: Delta-wing jet sign (mite with burrow)

The delta-wing jet or 'jet with contrail' sign represents the scabies mite at the end of its burrow.

Erythema chronicum migrans, an expanding annular erythema with central clearing, is the hallmark of which infection?

Answer: Lyme disease

Erythema migrans is the classic early cutaneous sign of Lyme disease caused by Borrelia burgdorferi.

Which condition is characterized by depigmented macules due to autoimmune destruction of melanocytes?

Answer: Vitiligo

Vitiligo results from autoimmune loss of melanocytes, producing sharply demarcated depigmented macules.

Which sunscreen ingredient provides broad-spectrum protection by physically reflecting UV radiation?

Answer: Zinc oxide

Zinc oxide is a physical (mineral) blocker that reflects and scatters both UVA and UVB radiation.

A biopsy of a facial plaque shows granulomatous inflammation with 'apple-jelly' color on diaskopy. What is the likely diagnosis?

Answer: Lupus vulgaris (cutaneous tuberculosis)

Apple-jelly nodules on diascopy with granulomatous histology are characteristic of lupus vulgaris, a form of cutaneous tuberculosis.