Abstract:
Here, we report an individual, eventually diagnosed with HMG-CoA synthase deficiency, who presented with a cyclic vomiting phenotype. HMG-CoA synthase deficiency is a rare disorder affecting ketone body synthesis in which affected individuals typically present at a young age with hypoketotic hypoglycemia, lethargy, encephalopathy, and hepatomegaly, usually triggered by catabolism (e.g., infection or prolonged fasting). This individual presented with recurrent episodes of vomiting and lethargy, often associated with hypoglycemia or hyperglycemia, at 3 years of age. Metabolic labs revealed nonspecific abnormalities in her urine organic acids (showing mild elevation of dicarboxylic acids with relatively low excretion of ketones) and a normal acylcarnitine profile. Given her clinical presentation, as well as a normal upper gastrointestinal series, esophagogastroduodenoscopy with biopsies, and abdominal ultrasound, she was diagnosed with cyclic vomiting syndrome at 3 years of age. Molecular testing completed at 7 years of age revealed a previously reported pathogenic sequence variant (c.1016+1G>A) and a novel likely pathogenic deletion (1.57 kB deletion, including exon 1) within HMGCS2 consistent with HMG-CoA synthase deficiency. This individual\'s presentation, mimicking cyclic vomiting syndrome, widens the clinical spectrum of HMG-CoA synthase deficiency. In addition, this case highlights the importance of molecular genetic testing in such presentations, as this rare disorder lacks specific metabolic markers.
摘要:
这里,我们报告一个人,最终诊断为HMG-CoA合成酶缺乏症,呈现周期性呕吐表型的人。HMG-CoA合酶缺乏症是一种罕见的影响酮体合成的疾病,其中受影响的个体通常在年轻时出现低酮症性低血糖。嗜睡,脑病,还有肝肿大,通常由分解代谢引发(例如,感染或长时间禁食)。这个人反复出现呕吐和嗜睡,通常与低血糖或高血糖有关,在3岁的时候。代谢实验室显示她的尿液有机酸中有非特异性异常(显示二羧酸的轻度升高,酮的排泄相对较低)和正常的酰基肉碱谱。鉴于她的临床表现,以及正常的上消化道系列,食管胃十二指肠镜检查与活检,还有腹部超声,她在3岁时被诊断为周期性呕吐综合征。在7岁时完成的分子检测揭示了先前报道的致病序列变异(c.1016+1G>A)和新的可能的致病缺失(1.57kB缺失,包括HMGCS2中的外显子1)与HMG-CoA合酶缺陷一致。这个人的介绍,模仿周期性呕吐综合征,拓宽了HMG-CoA合酶缺乏症的临床范围。此外,这个案例突出了分子基因检测在这些演示中的重要性,因为这种罕见的疾病缺乏特定的代谢标志物。