Phytosterolemia and Xanthomatosis

A 17-year-old girl presented with multiple xanthomas of the hands (Panel A) and the Achilles tendons, as well as a family history of vascular disease. Familial hypercholesterolemia was suspected, but the plasma cholesterol level was only mildly elevated. The levels of plant sterols in the plasma as measured with gas chromatography were 950 μmol of sitosterol per liter (normal value, <16) and 378 μmol of campesterol per liter (normal value, <24). Phytosterolemia with xanthomatosis was diagnosed. Phytosterolemia is an autosomal recessive disorder characterized by increased intestinal absorption of dietary sterols (not only cholesterol, but also plant sterols) and decreased biliary . . .