ABSTRACT
Objective:To analyze the clinical features and genotypes of mitochondrial complex Ⅰ deficiency due to NDUFAF5 gene mutations.Methods:Clinical data of 2 cases with mitochondrial complex Ⅰ deficiency due to NDUFAF5 gene mutations admitted in the Department of Pediatrics, Peking University First Hospital from February 2015 to July 2018 were retrospectively reviewed and followed up.Reported cases of mitochondrial complex Ⅰ deficiency due to NDUFAF5 gene mutations were searched in online databases, including the PubMed, Wanfang, Chinese Journal Full-Text Database and VIP database from January 1975 to February 2020 with " NDUFAF5" as the key word.Through literature review, clinical features and genotypes of mitochondrial complex Ⅰ deficiency due to NDUFAF5 gene mutations were summarized.Results:Case 1 showed mentor and mental regression after infection at the age of 1 year and 4 months.The condition of case 1 remained stable at the age of 5 year and 6 months at the last follow-up.Brain magnetic resonance imaging (MRI) showed multiple lesions in the white matter of the frontal and parieto-occipital lobes, basal ganglia, thalamus, cerebellum, brain stem and corpus callosum.Case 2 showed rapidly bilateral visual impairment at the age of 7 years and 4 months.The patient′s vision moderately recovered at the age of 8 years and 8 months.Brain MRI showed midbrain, periaqueductal gray, medulla oblongata and putamen lesions.Spinal MRI showed continuous lesions in the cervical cord 1-4.Genetic test showed NDUFAF5 gene c. 764C>T (p.Ala255Val) and c. 508C>T (p.Arg170Trp), homozygous c. 836T>G (p.Met279Arg) mutations in case 1 and case 2 respectively.Through online searching, 6 reports involving 14 cases were retrieved.The most common clinical phenotype was Leigh syndrome.Two cases had disease onset during the neonatal period, and their disease progressed rapidly and died within 1 year old.Eleven cases had onset during the infantile period, and 72.7% (8/11 cases) of them had a normal development.The common initial symptoms were mental or motor regression, feeding difficulty and dystonia.Seventy-two point seven percent (8/11 cases) had acute/subacute onset after infection, showing paroxysmal deterioration, and died in infancy or childhood.One patient developed dystonia in childhood and visual impairment in adulthood.Conclusions:The onset age ranged from neonatal period to childhood in patients with NDUFAF5 gene mutations, and their clinical phenotypes vary a lot.The main clinical phenotype is Leigh syndrome.Disease onset during the infantile period is frequent, and mostly presents paroxysmal deterioration after infection, while disease onset in childhood is rare.