A biopsy of a new plaque shows psoriasiform epidermal hyperplasia, but with small neutrophilic collections in the epidermis forming Kogoj spongiform pustules in addition to Munro microabscesses. Tortuous capillaries in dermal papillae are prominent. This pattern with spongiform pustules is most characteristic of which type of psoriasis?
- A Pustular psoriasis (generalized von Zumbusch) ✓
- B Plaque psoriasis
- C Guttate psoriasis
- D Psoriatic erythroderma
Correct answer: A. Pustular psoriasis (generalized von Zumbusch)
Explanation
Kogoj's spongiform pustules are collections of neutrophils within the spinous layer of the epidermis, forming a distinguishing feature of pustular psoriasis (particularly generalized pustular psoriasis/von Zumbusch type). In plaque psoriasis, Munro microabscesses (neutrophilic collections in the parakeratotic stratum corneum) predominate. Guttate psoriasis shows a less developed psoriasiform pattern. The spongiform pustule represents neutrophil infiltration into the spongiotic epidermis in pustular forms.
Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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