Common causes of hypoglycemia include hyperinsulinism, hormonal deficiencies, fatty acid oxidation disorders, and glycogen storage diseases; however, rare causes should also be considered for the condition. Mitochondrial complex III deficiency shows an autosomal recessive or a mitochondrial inheritance pattern. To date, mitochondrial complex III deficiency, nuclear type 3 attributable to a pathogenic variant of the UQCRB gene (MIM 615158) has been identified in only 2 pediatric patients; both presented with hypoglycemia and lactic acidosis. In this paper, we present a patient with mitochondrial complex III deficiency, nuclear type 3, UQCRB variant associated with acute hypoglycemia and lactic acidosis episodes. The male patient was admitted on the first day of life with tachypnea, metabolic acidosis, and hypoglycemia. Up to 10 years of age, he was admitted 7 times with abdominal pain, vomiting, and fever. His blood tests revealed hypoglycemia, metabolic acidosis, and hyperlactatemia. At 10 years of age, a whole-exome sequencing (WES) analysis was performed identifying a homozygous c.309_313delAGAAA (p.Glu104ArgfsTer10) pathogenic variant of the UQCRB gene. Once the common causes of hypoglycemia are excluded, it is essential to perform a WES analysis for other rare causes. Thus, rare disorders such as mitochondrial complex III deficiency can be diagnosed.
Mol Syndromol

中文翻译：

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一名患有复发性严重低血糖发作和线粒体复合体 III 缺乏症的患者，核型 3：一种新型 UQCRB 变体

低血糖的常见原因包括高胰岛素血症、激素缺乏、脂肪酸氧化障碍和糖原贮积病；但是，也应考虑罕见的原因。线粒体复合体 III 缺乏症表现为常染色体隐性遗传或线粒体遗传模式。迄今为止，仅在 2 名儿科患者中发现了由UQCRB基因 (MIM 615158) 的致病性变异引起的线粒体复合体 III 缺乏症，核型 3。两者均出现低血糖和乳酸酸中毒。在本文中，我们介绍了一名患有线粒体复合体 III 缺陷、核型 3、UQCRB的患者。变异与急性低血糖和乳酸酸中毒发作有关。男性患者在出生后第一天因呼吸急促、代谢性酸中毒和低血糖入院。直到 10 岁，他因腹痛、呕吐和发烧 7 次入院。他的血液检查显示低血糖、代谢性酸中毒和高乳酸血症。在 10 岁时，进行了全外显子组测序 (WES) 分析，鉴定了UQCRB基因的纯合 c.309_313delAGAAA (p.Glu104ArgfsTer10) 致病变异。一旦排除了低血糖的常见原因，就必须对其他罕见原因进行 WES 分析。因此，可以诊断出罕见的疾病，例如线粒体复合物 III 缺乏症。
摩尔综合症