[P1-155] A case with mitochondrial DNA depletion syndrome and mild methymalonic aciduria due to SUCLG1 mutations
[Objective] Mitochondrial DNA depletion syndromes (MDS) is an autosomal recessive disorder characterized by complex clinical and biochemical manifestations. This study aimed to investigate the clinical and laboratory features of a Chinese girl with mitochondrial DNA depletion syndrome due to SUCLG1 mutations. [Method] The proband, a girl, was hospitalized at the age of 9 months. She presented with muscular hypotonia, psychomotor retardation, failure to thrive, hearing impairment, scoliosis, thoracocyllosis and facial features. [Result] Her blood lactic acid and pyruvate were markedly increased. Liver damage and mild myocardial damage were found. Blood C4-dicarboxylic-carnitine was slightly increased. Mild methylmalonic aciduria was oberved. Cranial MRI showed T2 hyperintensities in bilateral caudate nuelei and lenticula. Brainstem auditory evoked potential shows severe hearing loss. Two heterozygous mutations, c.961C>G and c.713T>C, were detected in her SUCLG1 gene, confirmed the diagnosis of mitochondrial DNA depletion syndrome. [Conclusion] Mitochondrial DNA depletion syndrome is a rare inherited disease. For the patients with unexplained hypotonia retardation, mental retardation, abnormal movements, hearing disorder with mild methylmalonic acidemia and abnormal acylcarnitine profiles (C3\C4 increased), MDS should be pay attention to. Genetic analysis is important for the diagnosis of the patient and the prenatal diagnosis of the disease.
The firsrt two authers contributed equally to this paper.
The firsrt two authers contributed equally to this paper.