Ethylmalonic encephalopathy associated with respiratory failure

Ethylmalonic encephalopathy (EE) is a rarely encountered metabolic disease with autosomal recessive inheritance and is characterized by development retardation, acrocyanosis, petechiae and chronic diarrhea. In the literature, EE has usually presented itself with neurological disorders, developmental retardation, acrocyanosis and skin lesions. We encountered no case in the literature accompanied by respiratory failure. EE should be considered in the patients with severe respiratory failure, exanthematous skin lesion, acidosis, chronic diarrhea, neurological symptoms and pathological signal increment in the basal ganglia on MRI together with the history of sibling death and consanguineous marriage. Herein, a 2.5-year-old boy case, who presented with exanthematous lesions over the body and respiratory failure and had lactic acidemia, increase in serum C4 and C5 acylcarnitine derivatives, excretion of ethylmalonic acid, methyl succinic acid, isovalerylglycine and isobutyrylglycine in the urine, pathological signal increment in the basal ganglia on CT and MRI, and firstly defined homozygote deletion in the ETHE1 gene in genetic analysis. In conclusion, we intended to emphasize consider underlying EE metabolic disease in the cases with frequent lower respiratory tract infection and respiratory failure in the presence of hypotonia and neuromotor developmental retardation.

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