A 55-year-old man has brownish pigmentation around the medial ankles with brawny induration and an itchy erythematous rash over both lower legs. Doppler shows venous incompetence. The pigmentation results mainly from:

• A Melanocyte proliferation induced by chronic scratching
• B Drug-induced melanogenesis from diuretic therapy
• C Post-inflammatory hyperpigmentation from topical steroid use
• D Extravasated red blood cells with haemosiderin deposition ✓

Explanation

Venous hypertension causes red cell extravasation into the dermis; haemosiderin from degraded haemoglobin deposits around the medial malleolus, producing the classic brown pigmentation and induration of lipodermatosclerosis with overlying stasis eczema. Compression therapy addresses the underlying venous insufficiency. Melanocyte proliferation is not the mechanism here.

Reference: Habif Clinical Dermatology, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.