Non-syndromic patients with infantile spasms and malformations of cortical development: absence of seizures in siblings
Background: Parents of children with infantile spasms undergoing epilepsy surgery typically inquire about the risk of other children for a similar affliction. Here, we determined whether non-syndromic patients with infantile spasms and malformation of cortical development (MCD) have a family history of seizures, particularly in siblings.
Patients and methods: We selected 29 children with intractable infantile/epileptic spasms who underwent surgery (mean age at surgery: 4.4±3.8 years; 12 males, 17 females; age range 0.8-14.9 years). A pathological diagnosis of MCD was confirmed in all the patients. Family (including parents, and siblings) history of seizures was acquired in all patients through neurology chart review/telephonic interview.
Results: Pathological diagnosis of migration disorder (16) and cortical dysplasia (9) was made in these patients. Diagnosis of hemimegalencephaly, dysembryoplastic neuroepithelial tumor (DNET), lissencephaly type1 and porencephaly was also confirmed in 4 different patients. None of the siblings in any family (total number of siblings in the group = 30) were affected by infantile spasms or other types of seizures. The maternal aunt of one patient and mother of another patient had a history of childhood seizures for short durations.
Conclusions: Our retrospective study showed that patients with infantile spasms with MCD who underwent resective surgery have low sibling recurrence risk for seizures. Our study suggests that de novo mutations and non-genetic or epigenetic factors are major causes of infantile spasms due to MCD.