[Two cases of creatine deficiency syndrome caused by gene mutations and literature review].

OBJECTIVES

To summarize the clinical manifestations and genetic characteristics of creatine deficiency syndrome (CDS) caused by gene mutations.

METHODS

A retrospective analysis was conducted on the clinical and genetic data of two children diagnosed with GAMT deficiency-type CDS at the Children's Medical Center of Xiangya Hospital, Central South University, from December 2020 to December 2024.

RESULTS

The two patients presented with symptoms in infancy, and both had compound heterozygous mutations in the gene. Case 1 exhibited seizures and intellectual disability, while Case 2 had intellectual disability and attention-deficit hyperactivity disorder. Magnetic resonance spectroscopy of cranial MRI in both patients indicated reduced creatine peaks. After creatine treatment, seizures in Case 1 were controlled, but both patients continued to experience intellectual disabilities and behavioral issues. As of December 2024, a total of 21 cases have been reported in China (including this study), and 115 cases have been reported abroad. All patients exhibited developmental delay or intellectual disabilities, with 66.9% (91/136) experiencing seizures, 33.8% (46/136) presenting with motor disorders, and 36.8% (50/136) having behavioral problems. Seventy-five percent (102/136) of patients received creatine treatment, leading to significant improvements in seizures and motor disorders, although cognitive improvement was not substantial.

CONCLUSIONS

GAMT deficiency-type CDS is rare and presents with nonspecific clinical features. Timely diagnosis facilitates targeted treatment, which can partially improve prognosis.