Authors :
Presenting Author: Lekshmi Peringassery Sateesh, MD – Baylor college of medicine
Rima El Atrache, MD – Baylor college of medicine
Leslie Beltran, MD – Baylor college of medicine
Mariana Carretero Murillo, MD – Baylor college of medicine
Danielle Takacs, MD – Baylor College of Medicine/Texas Children's Hospital
Rationale:
Infantile epileptic spasm syndrome (IESS or IS) outcomes vary vastly depending on the underlying causes, with structural etiologies often having a poorer prognosis. However, little is known about the clinical features, natural history, and prognosis of this condition, based on different structural brain abnormalities. Methods:
The study is a retrospective single-institutional analysis of infants diagnosed with IS due to structural etiology, other than tuberous sclerosis complex. We included patients between 2 months and 2 years of age, diagnosed with IS at Texas Children’s Hospital between 2019 and 2023, and with abnormal MRI findings.
We analyzed the relevant demographic and clinical data, with MRI findings associated with IS refractoriness in this structurally based cohort. Refractory infantile spasms were defined by the presence of spasms on follow-up EEG around 2 weeks after treatment initiation.
Results:
We included 34 patients (median age at diagnosis 8 months, 40% females). Refractory spasms occurred in 55% of patients with a seizure history prior to spasms, compared to 42% without such a history. Other seizure types occurred in 10% of infants with IS who had no prior seizure history vs 29% with a history of prior seizures. Developmental improvement was seen in 58% without prior seizures compared to 55% with history of seizures. New seizure types were identified post-treatment in 17% of infants with IS who had no prior seizure history vs 36% of those who had prior seizures. Patients with refractory spasms had earlier spasms onset (5 vs 6 months) and lower female representation (29% vs. 47%) compared to infants with nonrefractory spasms. Pre-spasms seizures were more common in the refractory group (71% vs. 59%).
Half of the patients with IS had acquired structural abnormalities such as hypoxic ischemic injury (HIE), vascular etiologies including intracranial hemorrhages, strokes, subdural hemorrhages, and sequelae of intracranial infections. Around 35% of patients had nonspecific abnormalities, which varied from subtle hyperintensity of corpus callosum, intracranial dysmorphisms including pontine hypoplasia, corpus callosal dysplasias, and white matter abnormalities. Developmental etiologies, including cortical migration abnormalities (lissencephaly, focal cortical dysplasia) and neuronal proliferation abnormalities (heterotopia), were seen in 15% of infants.<