Dermatopathology Flashcards

A biopsy shows a wedge-shaped superficial and deep perivascular lymphocytic infiltrate with numerous plasma cells. In the right clinical context, this suggests which infection?

Answer: Secondary syphilis

Plasma-cell-rich perivascular and lichenoid infiltrates should raise suspicion for secondary syphilis.

Flame figures (eosinophilic material coating collagen) are the histologic hallmark of which condition?

Answer: Wells syndrome (eosinophilic cellulitis)

Flame figures — degranulated eosinophil major basic protein on collagen — are characteristic of Wells syndrome.

A panniculitis biopsy shows inflammation predominantly in the connective-tissue septa without vasculitis. What is the most likely diagnosis?

Answer: Erythema nodosum

Erythema nodosum is the prototypical septal panniculitis without vasculitis.

A dense dermal nodular infiltrate of neutrophils with papillary dermal edema, without vasculitis, in a febrile patient suggests which diagnosis?

Answer: Sweet syndrome (acute febrile neutrophilic dermatosis)

A diffuse dermal neutrophilic infiltrate with marked papillary edema and no true vasculitis characterizes Sweet syndrome.

Which histochemical stain best demonstrates amyloid deposits in the skin, showing apple-green birefringence under polarized light?

Answer: Congo red

Congo red stains amyloid and produces apple-green birefringence under polarized light.

Necrobiotic collagen surrounded by palisading histiocytes with abundant dermal mucin is characteristic of which condition?

Answer: Granuloma annulare

Granuloma annulare shows palisaded histiocytes around necrobiotic collagen with prominent mucin in the center.

Corps ronds and grains, reflecting abnormal keratinization with acantholytic dyskeratosis, are seen in which disorder?

Answer: Darier disease

Corps ronds and grains are the characteristic dyskeratotic cells of Darier disease (keratosis follicularis).