Diagnostics features and literature review of congenital disorder of glycosylation type Ik

Objective To explore the clinical diagnostic features of congenital disorder of glycosylation type Ik (CDG-Ik). Methods The clinic data of 1 case of CDG-Ik who was admitted to the department of pediatrics of the First People′s Hospital of Jining on June 7, 2018 was analyzed retrospectively. The clinical data and genetic test results were analyzed and relevant literatures were reviewed. Results The male infant was 1 year old, with intermittent twitch, intraocular inclination, poor visual and auditory response, low ear position, no grasp consciousness in both hands, head instability, backward motor development, decreased muscle tone and decreased knee tendon reflex. Examination revealed abnormal liver function, myocardial damage, low developmental quotient. The head MRI revealed wide cerebral fluid cavity and cerebellar atrophy. The ALG1 gene had a homozygous mutation, c. 1312 C>T, resulting in amino acid changes p. R438W, which was a missense mutation. The children was diagnosed as CDG-Ik. Through family verification and analysis, both the parents of the infant showed heterozygous variation at this site, which was suspected to be pathogenic variation. Conclusions CDG-Ik is an autosomal recessive genetic disease, and the possibility of this disease should be considered for multiple organs damage due to unknown reasons, especially for the children with backward development of intelligence and motor, strabismus and cerebellar atrophy. ALG1 gene detection can facilitate the diagnosis. Key words: Congenital disorder of glycosylation; ALG1 gene; Mutation; Inherited metabolic diseases