Ethylmalonic encephalopathy (EE) is a rare metabolic disorder caused by dysfunction of ETHE1 protein, a mitochondrial dioxygenase involved in hydrogen sulfide (H₂S) detoxification. EE is usually a fatal disease with a severe clinical course mainly associated with developmental delay and regression, recurrent petechiae, orthostatic acrocyanosis, and chronic diarrhoea. Treatment includes antioxidants, antibiotics that lower H₂S levels and antispastic medications, which are not curative. The mutations causing absence of the ETHE1 protein, as is the case for the described patient, usually entail a severe fatal phenotype. Although there are rare reported cases with mild clinical findings, the mechanism leading to these milder cases is also unclear. Here, we describe an 11-year-old boy with an ETHE1 gene mutation who has no neurocognitive impairment but chronic diarrhoea, which is controlled by oral medical treatment, and progressive spastic paraparesis that responded to Achilles tendon lengthening.

丙二酸脑病（EE）是由ETHE1蛋白（参与硫化氢（H ₂ S）排毒的线粒体双加氧酶）功能异常引起的罕见代谢疾病。EE通常是一种致命疾病，临床病程较重，主要与发育延迟和消退，复发性瘀斑，体位性肢端氰症和慢性腹泻有关。治疗包括抗氧化剂，降低H _2的抗生素S水平和抗痉挛药，不能治愈。如所描述的患者的情况那样，导致缺乏ETHE1蛋白的突变通常引起严重的致命表型。尽管很少有报道病例具有轻度的临床发现，但导致这些轻度病例的机制也不清楚。在这里，我们描述了一个具有ETHE1基因突变的11岁男孩，该男孩没有神经认知障碍，但有慢性腹泻（由口服药物治疗控制）和进行性跟腱痉挛性痉挛性轻瘫。