Infantile Spasms of Unknown Cause: Who Can Have a Good Outcome?

Exhaustive clinical examination of etiology and initial response to first-line treatment in 577 children with infantile epileptic spasm syndrome children: A 5-year retrospective observational study

OBJECTIVE

Employing whole-exome sequencing (WES) technology to investigate the etiology of infantile epileptic spasm syndrome (IESS), and determining whether different etiologies exhibit phenotypic variations, while elucidating the potential associated factors, might improve short-term responses to first-line treatment.

METHODS

We retrospectively evaluated patients with IESS admitted for treatment between January 2018 and June 2023. Clinical phenotypic differences among etiological classifications and clinical manifestations were analyzed. Variable selection using the best subset method was performed, followed by logistic regression analysis to identify the factors influencing treatment response.

RESULTS

A total of 577 patients were included; 412 completed trio-WES. Magnetic resonance imaging abnormalities were detected in 387 patients (67.1%). Patients with etiology as structural abnormalities were likelier to have non-spasms at the initial seizure onset. A total of 532 patients completed the first-line treatment; 273 patients received it for the first time at our hospital (initial response rates: 30.1% and 42.1%, respectively). The response group had a lower proportion of early-onset seizures (≤3 months) than the no-response group (11.3% vs. 23.7%, p < 0.01 and 11.3% vs. 21.5%, p = 0.03, respectively). Logistic regression analysis indicated that earlier initiation of first-line treatment was associated with a higher likelihood of an initial response. However, the etiological classification did not have a significant impact on the initial response.

INTERPRETATION

IESS patients with structural abnormalities are more likely to present with non-spasm seizures at initial onset. Early initiation of first-line treatment is crucial; however, initial responses may be less favorable when seizures occur in early infancy.

High-Dose Prednisolone for Treatment of Infantile Spasms After Presumed Perinatal Stroke

ABSTRACT

BACKGROUND: High-dose prednisone and prednisolone have been increasingly studied as a lower-cost alternative to adrenocorticotropic hormone for the treatment of infantile spasms, but this treatment has not been well studied in children with infantile spasms due to perinatal stroke. METHODS: We identified a girl with new-onset infantile spasms due to presumed perinatal left middle cerebral artery stroke seen in our hospital's pediatric stroke clinic in 2019. RESULTS: This girl developed infantile spasms at 9 months old. She had right hemiplegic cerebral palsy due to her perinatal stroke but had been otherwise previously healthy. Modified hypsarrhythmia was confirmed on prolonged video-electroencephalography. High-dose prednisolone at 8 mg/kg per day was initiated on the sixth day of spasms. She was treated with this dose for 2 weeks and then tapered over 5 weeks. The girl became seizure-free after receiving her first dose of prednisolone and experienced no significant adverse effects during therapy. Routine electroencephalography after completion of prednisolone taper confirmed resolution of modified hypsarrhythmia and no epileptiform discharges. She continued to make excellent development progress during and after treatment. CONCLUSION: This case suggests high-dose prednisolone could be considered for first-line therapy for children with infantile spasms due to perinatal stroke; further study is needed.

Infantile Spasms: Outcome in Clinical Studies

Children with infantile spasms are likely to have a poor outcome. Outcome measures for infantile spasms include primary response to treatment, relapse of spasms, neurological development, death, and progression to another type of epilepsy (Consensus Statements of the WEST Delphi Group 2004). This review is based mainly on prospective studies and emphasizes data about the current first-line drugs, adrenocorticotropic hormone, vigabatrin, and prednisolone, taking into account the proportion of patients with known and unknown etiology, which has a very strong effect on seizure outcome. In most studies, hormonal treatment (adrenocorticotropic hormone or prednisolone) is the optimal monotherapy, except for patients with tuberous sclerosis complex, in whom vigabatrin appears superior. Combination therapy (hormones plus vigabatrin) may well be more effective than either agent alone. The underlying etiology is the most important prognostic factor. In studies with a long follow-up (up to 50 years), a favorable cognitive outcome has been observed in approximately one quarter of patients and complete seizure freedom in one-third. Autism is relatively frequent, and premature mortality is high throughout life. Modifiable prognostic factors include early recognition of the spasms with prompt treatment, short duration of hypsarrhythmia, prompt treatment of relapses of spasms and multifocal epileptic discharges, and early treatment of adverse effects. It is hoped that eventually advanced genetics and molecular data will allow an understanding of the pathogenetic mechanisms of many specific etiologies to allow disease-specific treatment such as is emerging for tuberous sclerosis.

Neutrophil to lymphocyte rate and serum prealbumin maybe predictors for abnormal high blood pressure caused by adrenocorticotropic hormone therapy in children with epileptic spasms: two cases report

Epileptic spasms are a catastrophic form of epilepsy. When epileptic spasms occur under 2-year-old, they may be also called “infantile spasms”. Adrenocorticotropic hormone (ACTH) is recommended as first line intervention for the treatment of epileptic spasms without tuberous sclerosis complex. The chief risks of ACTH therapy are immunosuppression and hypertension. We reported rare cases of abnormal high blood pressure in two male epileptic spasms patients during ACTH therapy. Both patients’ blood pressure reached a high blood pressure stage 2 on the 9th day and 10th day of ACTH treatment, respectively. The blood pressure returned to normal range after the drug dosage was reduced or stopped. The lower level of neutrophil%, neutrophil count, and a higher level of lymphocyte%, lymphocyte count and prealbumin than normal range were observed in both patients before ACTH therapy. The neutrophil to lymphocyte rate might be a predictor for high blood pressure among patients treated with ACTH. The rates of both patients were under 0.50 (0.42 for Case 1 and 0.17 for Case 2). We reported the documented cases in two Chinese pediatric patients who suffered from epileptic spasms treated with ACTH resulted in abnormal high blood pressure, which could be predicted by using neutrophil to lymphocyte rate. We also mentioned serum prealbumin might be another predictor. More clinical data is required to elucidate the relationship between serum prealbumin level and blood pressure.