You are correct. Benign lipomatous tumors are rare and may localize inside (nervous lipomatosis) or outside the neural sheath of the median nerve. Based on the fusiform dilatation of the median nerve with nerve fascicles stretched by unresectable adherent fibrofatty tissue, a clinical diagnosis of nervous lipomatosis was made. Conservative decompression by release of carpal ligament was adopted. The patient's symptoms gradually improved and she reported no residual deficits at 12-month follow-up.

You are correct. This patient has erythematous lichenified plaques on the wrist and hand with evidence of excoriation. The morphology and prolonged intermittent course of pruritus favor atopic dermatitis. Scabies, which favors flexural and intertriginous areas, tends to wane after months of infestation in healthy patients; in elderly or immunocompromised patients it may develop into thick, crusted scaly lesions (Norwegian scabies) that spread. Prurigo nodularis presents with dome-shaped papules or nodules.

You are correct. Skin biopsy showed leukocytoclastic vasculitis, consistent with levamisole vasculopathy related to contaminated cocaine. Levamisole is an animal dewormer frequently used to cut cocaine. The majority of cocaine sampled by the U.S. Drug Enforcement Agency is reportedly adulterated with levamisole. Levamisole toxicity can present with neutropenia, hyponatremia, arthralgias, positive perinuclear antineutrophil cytoplasmic antibody, purpura, and necrotic skin lesions.