A 40-year-old woman has flat-topped violaceous papules on the flexor wrists. Oral examination shows Wickham striae. Skin biopsy shows a 'saw-tooth' appearance of rete ridges with a dense band-like lymphohistiocytic infiltrate at the DEJ and colloid (Civatte) bodies. These bodies represent:

• A Aggregates of neutrophils in the papillary dermis
• B Extruded melanin granules from melanocytes
• C Intraepidermal dyskeratotic cells from acantholysis
• D Apoptotic keratinocytes with retained cytoplasmic organelles ✓

Explanation

Civatte (colloid/hyaline) bodies in lichen planus are apoptotic keratinocytes (degenerate basal cells) that have undergone programmed cell death due to cytotoxic T-lymphocyte attack at the dermo-epidermal junction. They appear as eosinophilic, homogeneous, ovoid bodies in the lower epidermis or upper dermis. They stain positive for IgM by DIF. Similar bodies are seen in other lichenoid disorders such as lupus erythematosus and lichenoid drug reactions.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.