Whole-Exome Sequencing Analysis of a Young Obese Japanese Patient with Ketosis-Prone Diabetes: A Case Report

Ketosis-prone diabetes (KPD) is characterized by episodes of diabetic ketosis or diabetic ketoacidosis (DKA) requiring insulin therapy, followed by periods during which insulin treatment may be discontinued. We herein report a case of a young obese male with clinical features consistent with KPD. He developed diabetic ketosis at the age of 16 years but recovered insulin secretion soon after undergoing intensive therapy, allowing for insulin withdrawal. At 25 years of age, he developed severe DKA again, but was able to discontinue insulin therapy after two months. Whole-exome sequencing identified a rare heterozygous missense variant (p.R51Q) in ARRB1. The ARRB1 variant may be a genetic contributor to KPD.