title: Numerous intertriginous xanthomas in infant: A diagnostic clue for sitosterolemia.
abstract: Sitosterolemia is a very rare autosomal recessive lipoprotein metabolic disorder caused by homozygous or compound heterozygous mutations in one of the two adenosine triphosphate-binding cassette transporter genes, ABCG5 and ABCG8. Sitosterolemia is clinically characterized by xanthomas and atherosclerosis, arthritis, fever, hemolysis and macrothrombocytopenia even in early childhood. We described a 16-month-old girl, who had numerous yellowish-brown intertriginous xanthomas along the skin creases on the extremities with severe hypercholesterolemia and elevated plant sterol levels. Histopathologically, xanthoma showed aggregation of foam cells in the dermis with a zone of mucin deposits in the dermal papilla. Electron microscopy showed numerous membrane-bound lipid droplets and multivesicular lipid bodies in the foam cells, a round cell containing lipid droplets in the basal cell layer and abundant mucin deposits just beneath the basal lamina. Diagnosis of sitosterolemia was confirmed by DNA sequencing showing compound heterozygosity for previously reported missense mutations in exon 9 of ABCG5. Infants presenting with multiple xanthomas should be investigated for sitosterolemia, if there is no family history of dyslipidemia.
authors.affiliation: Department of Dermatology, Kawasaki Medical School, Kurashiki, Japan. go-yama@med.kawasaki-m.ac.jp.
authors.forename: Takenobu
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Department of Pediatrics, Kawasaki Medical School, Kurashiki, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Matsuda
authors.affiliation: Department of Pediatrics, Nagasaki University School of Medicine, Nagasaki, Japan.
authors.forename: Sumito
authors.initials: S
authors.lastname: Dateki
authors.affiliation: Department of Pediatrics, Kawasaki Medical School, Kurashiki, Japan.
authors.forename: Kazunobu
authors.initials: K
authors.lastname: Ouchi
authors.affiliation: Department of Dermatology, Kawasaki Medical School, Kurashiki, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Fujimoto
mesh_terms: D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D007223:Infant; D007410:Intestinal Diseases / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D008052:Lipid Metabolism, Inborn Errors / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D010840:Phytosterols / Q000009:adverse effects*; D012867:Skin / Q000473:pathology / Q000648:ultrastructure*; D014973:Xanthomatosis / Q000209:etiology* / Q000473:pathology
chemical_list: D010840:Phytosterols
keywords: adenosine triphosphate-binding cassette subfamily G member 5 (ABCG5); electron microscopy; hypercholesterolemia; sitosterolemia; xanthoma