A 38-year-old woman with a history of ischemic heart disease presents with disfiguring skin lesions. Physical examination shows xanthomas on the dorsal surface of both hands (shown in the image) and xanthelasmas of the eyelids. Laboratory studies reveal serum cholesterol of 820 mg/dL and significantly elevated serum triglycerides and LDL. Which of the following histopathologic findings would be expected in a biopsy of this patient’s skin lesions?
Dermal calcium deposits
Hypertrophic scar tissue
Smooth muscle hyperplasia
- Ans.C. Foamy macrophages
- This patient has familial hypercholesterolemia and has inherited mutations in the LDL receptor gene.
- The LDL receptor is a cell surface glycoprotein that regulates plasma cholesterol by mediating endocytosis and recycling of apolipoprotein (apo)E.
- Lacking LDL receptor function, high levels of LDL circulate, are taken up by tissue macrophages, and accumulate to form occlusive arterial plaques (atheromas) and papules or nodules of lipid-laden, foamy macrophages (xanthomas).
- The other choices are not expected findings in xanthomas.