Genetic Etiology of Infantile Spasms in Peruvian Children: A Multicenter Study

Introduction: Infantile epileptic spasms syndrome (IESS) is a group of severe encephalopathies during infancy. In recent years, the search for genetic causes has gained importance. This study aimed to describe the genetic causes of IESS in children <2 years of age with access to diagnostic studies. Materials and Methods: A case series study was conducted in 6 pediatric neurology centers in Peru. Medical record data of children <2 years of age diagnosed with IESS were assessed. Results: Fifty-five cases were included, with a median age at diagnosis of 6 months, predominantly male (58.12%, n = 32), and from Lima (52.73%, n = 31). The predominant etiologic category was genetic-structural (38.18%, n = 21), with tuberous sclerosis standing out, followed by structural-congenital (30.90%, n = 17), genetic (27.27%, n = 15), and metabolic (3.63%, n = 2). All presented mixed neurodevelopmental delay, most of them of severe grade (63.64%, n = 35). The predominant electroencephalographic pattern was hypsarrhythmia (67.27%, n = 37). Vigabatrin was the most frequently used control medication (54.55%, n = 30). A total of 58.18% (n = 32) progressed to some type of epilepsy, whereas 23.64% (n = 13) controlled spasms. Twenty-four variants in 21 different genes and 2 chromosomal alterations were found. Conclusions: Genetic etiology was common and diverse in IESS. The genetic-structural category was the most frequent, followed by the structural-congenital category. A wide range of genetic variants was found in one-third of the cases. Prompt genetic identification in IESS is recommended to optimize treatment and improve the prognosis.