ESPE Abstracts

Objective: Complex glycerol kinase deficiency (CGKD) is a rare genetic syndrome which belongs to the group of contiguous gene syndromes and is caused by microdeletion of genes located in Xp21, which also be called Xp21 contiguous gene deletion syndrome. Patients with CGKD present with features characteristic for adrenal hypoplasia congenita (AHC), glycerol kinase deficiency (GKD), Duchenne muscular dystrophy (DMD) and sometimes intellectual disability or hypertriglyceridemia. Timely genetic testing can provide early diagnosis. We describe our experience with four such patients to deepen the understanding of this disease.

Method: The data of four children with CGKD was summarized. The information of age of onset, gender, incidence, and auxiliary examinations (adrenal cortex function testing, creatine kinase testing, blood lipid testing, blood glucose testing, gene testing, etc.) was included. This study conducted a simple analysis and reviewed relevant literature.

Result: All 4 patients were male, with 1 case developing symptoms in the neonatal period (9 days after birth), 1 case in the infancy period (2 months after birth), and 2 cases in the preschool period (1 case at 3 years and 10 months, 1 case at 6 years and 3 months). All cases had experienced convulsions caused by hypoglycemia. Follow up of the children, 3 cases were well controlled, and 1 case died of infection. All patients had varying degrees of primary adrenal cortex dysfunction accompanied by electrolyte disorders (2 cases with hyperkalemia and 2 cases with hyponatremia), extremely elevated creatine kinase, and hypertriglyceridemia. Genetic testing had shown varying degrees of gene deletions in the Xp21 region of the chromosome (case 1 had a missing fragment size of 2.42Mb, case 2 had a missing fragment size of 1.21Mb, case 3 had a missing fragment size of 8.81Mb, and case 4 had a missing fragment size of 6.16Mb).

Conclusion: The size of missing gene fragments in CGCK patients may have some correlation with clinical manifestations. The larger the missing fragment, the more complex the clinical presentation, and the earlier the onset age. The smaller the missing fragment, the less typical the clinical presentation, and the later the onset age. Early diagnosis and treatment can help improve the quality of life and survival time of CGDK patients.

Keywords: Complex glycerol kinase deficiency (CGKD), adrenal hypoplasia congenita (AHC), glycerol kinase deficiency (GKD), Duchenne muscular dystrophy (DMD)