Unusual xanthomas in a young patient with heterozygous familial hypercholesterolemia and type III hyperlipoproteinemia

✍ Scribed by Feussner, Giso; Dobmeyer, Jürgen; Nissen, Henrik; Hansen, Torben Stiig

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 626 KB
• Volume: 65
• Category: Article
• ISSN: 0148-7299
• DOI: 10.1002/(sici)1096-8628(19961016)65:2<149::aid-ajmg14>3.0.co;2-q

✦ Synopsis

We report on a 20-year-old man with the combination of two independent familial lipoprotein disorders: heterozygous familial hypercholesterolemia (FH) and type I11 hyperlipoproteinemia (HLP). Familial hypercholesterolemia was diagnosed by elevated total and low density lipoprotein cholesterol levels and family history. By denaturing gradient gel electrophoresis, DNA sequencing and restriction fragment length polymorphism analysis, a G+A splice donor mutation in intron 3 of the proband's low density lipoprotein receptor gene was identified as the underlying molecular defect. This mutation was described previously as a receptor-negative founder mutation in Norway (FH-Elverum) and subsequently in 6 unrelated heterozygous English patients, creating a severe phenotype of familial hypercholesterolemia. Type I11 HLP was confirmed by homozygosity for apolipoprotein (apo) E2 and an elevated ratio of very low density lipoprotein cholesterol to serum triglycerides (0.40; normal ratio about 0.20). The patient has unusual flat xanthomas in the interdigital webs of the hands which are normally not found in either disease. These dermatological findings might therefore be indicative of the rare combination of both disorders of lipoprotein metabolism in one individual.