Histopathology of a plaque psoriasis biopsy shows regular epidermal hyperplasia, elongated rete ridges, suprapapillary plate thinning, tortuous papillary vessels, and neutrophilic collections in the stratum corneum. The latter are called:

• A Russell bodies
• B Pautrier microabscesses
• C Munro microabscesses ✓
• D Darier's bodies

Explanation

Munro microabscesses are collections of neutrophils in the parakeratotic stratum corneum of psoriasis, formed when neutrophils migrate from dilated papillary vessels through the epidermis. Kogoj's spongiform pustule is a similar collection in the granular/spinous layer (more characteristic of pustular psoriasis). Pautrier microabscesses (clusters of atypical lymphocytes in epidermis) are seen in mycosis fungoides. Russell bodies are immunoglobulin-containing plasma cell inclusions.

Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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