A case of ezetimibe-effective hypercholesterolemia with a novel heterozygous variant in ABCG5.

A case of ezetimibe-effective hypercholesterolemia with a novel heterozygous variant in ABCG5. Endocr J. 2020 Jul 09;: Authors: Nakano Y, Komiya C, Shimizu H, Mishima H, Shiba K, Tsujimoto K, Ikeda K, Kashimada K, Dateki S, Yoshiura KI, Ogawa Y, Yamada T Abstract Sitosterolemia is caused by homozygous or compound heterozygous gene mutations in either ATP-binding cassette subfamily G member 5 (ABCG5) or 8 (ABCG8). Since ABCG5 and ABCG8 play pivotal roles in the excretion of neutral sterols into feces and bile, patients with sitosterolemia present elevated levels of serum plant sterols and in some cases also hypercholesterolemia. A 48-year-old woman was referred to our hospital for hypercholesterolemia. She had been misdiagnosed with familial hypercholesterolemia at the age of 20 and her serum low-density lipoprotein cholesterol (LDL-C) levels had remained about 200-300 mg/dL at the former clinic. Although the treatment of hydroxymethylglutaryl-CoA (HMG-CoA) reductase inhibitors was ineffective, her serum LDL-C levels were normalized by ezetimibe, a cholesterol transporter inhibitor. We noticed that her serum sitosterol and campesterol levels were relatively high. Targeted analysis sequencing identified a novel heterozygous ABCG5 variant (c.203A>T; p.Ile68Asn) in the patient, whereas no mutations were found in low-density lipoprotein receptor (LDLR), proprotein convertase subtilisin/kexin type 9 (PCSK9), or Niemann-Pick C1-like intr...
Source: Endocrine Journal - Category: Endocrinology Tags: Endocr J Source Type: research