Rufini S, Bragetti P, Brunelli B, Campolo G, Lato M
Istituto di Farmacologia Medica, Università degli Studi di Perugia, Italia.
Pediatr Med Chir. 1993 Jan-Feb;15(1):63-6.
A 9-year-old girl was referred to our hospital after recurrent episodes of hypoglycemia, altered consciousness and persistent vomiting without acetonemia or myopathic symptoms. Other pertinent laboratory data included elevated BUN, hyperammonemia and very low levels of triglycerides with elevated free fatty acids. The patient was born from unaffected but related parents (second cousins) and the illness was previously diagnosed as Reye encephalopathy. Recurrence of similar attacks suggested an underlying metabolic disorder. Several syndromes of impaired FFA beta oxidation were taken into account and discarded successively after laboratory investigations: systemic carnitine deficiency, Medium and Long Chain Acyl-CoA Dehydrogenase deficiency and Multiple Acyl CoA Dehydrogenation deficiency (Glutaric aciduria, Ethylmalonic-adipic aciduria and riboflavin-responsive multiple acyl CoA dehydrogenation deficiency). Urinary and hematic gas-chromatography and Mass-Spectrometry show no abnormality in Medium Chain fatty acids and in C6-C10 dicarboxylic acids. Carnitine plasma concentrations (both total and free) were above normal levels while in urine acetyl carnitine was low in respect to longer acyclic radicals. Among metabolic defects located at the level of hepatic fatty acid oxidation, only Carnitine Transferase deficiency can explain this peculiar mosaic of data (precursors of the blocked reaction are elevated in blood whereas lack of the metabolites derived uniquely from this reaction explains all the clinical manifestations).
一名9岁女孩在反复出现低血糖、意识改变和持续性呕吐且无酮血症或肌病症状后被转诊至我院。其他相关实验室数据包括血尿素氮升高、高氨血症以及甘油三酯水平极低伴游离脂肪酸升高。该患者的父母为未受影响的近亲(二级表亲),其疾病先前被诊断为瑞氏脑病。类似发作的复发提示存在潜在的代谢紊乱。考虑了几种脂肪酸β氧化受损的综合征,并在实验室检查后相继排除:全身性肉碱缺乏症、中链和长链酰基辅酶A脱氢酶缺乏症以及多种酰基辅酶A脱氢酶缺乏症(戊二酸尿症、乙基丙二酸 - 己二酸尿症和核黄素反应性多种酰基辅酶A脱氢酶缺乏症)。尿液和血液的气相色谱和质谱分析显示中链脂肪酸和C6 - C10二羧酸无异常。血浆肉碱浓度(总肉碱和游离肉碱)高于正常水平,而尿液中乙酰肉碱相对于较长的无环基团含量较低。在位于肝脏脂肪酸氧化水平的代谢缺陷中,只有肉碱转移酶缺乏症可以解释这种独特的数据组合(受阻反应的前体在血液中升高,而仅源于该反应的代谢产物缺乏则解释了所有临床表现)。