A Prospective Study of Infantile Spasms: Clinical and Therapeutic Correlations

Abstract

Of 363 infants with infantile spasms (IS) admitted into our hospital during an 18-year period, 286 were closely followed for at least 6 years and form the basis of this report. These patients were divided into symptomatic (165 cases) or cryptogenic (121 cases) groups. The cryptogenic group consisted of patients exhibiting no etiological clues and in whom development until the onset of the disorder was normal, even if some had mild impurities in their previous biography. We did not use the "doubtful subgroup" proposed by others for infants with no known etiology but with definite previous psychomotor delay. Close monitoring of ictal phenomena confirmed the latter variability and strengthened the view that IS should not be classified as a distinct seizure pattern. No statistically significant clues for etiology or prognosis were offered by the analysis of prevailing seizure patterns or frequency. Etiologies in the symptomatic group were subsumed within pre-, peri-, and post-natal periods. Asphyctic events predominated in this series. Dysgenetic, infectious, metabolic, and hemorrhagic factors were almost equally represented, except for the first, which was found somewhat more frequently. That postimmunization reactions may be one cause of IS was not considered sufficiently documented. A gender predominance ( 8 : 0 = 2: 1 ) occurred within the symptomatic group only. No significant genetic trends could be revealed after excluding those disorders that themselves carry clear genetic implications. Age of onset was earlier than in most reports because we corrected for true conceptional age. When this was done, onset of IS below 3 months carried a more unfavorable prognosis (p < 0.001). As expected, the presence of preceding neurological impairment resulted in worse outcome. Infants who had typical hypsarrhythmic EEG at the onset of IS fared better than those with atypical EEG (p < 0.02). While bacterial infections usually aggravated the condition, viral ones seemed to temporarily ameliorate it. On a short-term follow-up (10 months from onset treatment), the hypsarrhythmic pattern may disappear in both groups regardless of therapies, but on a long-term basis (6 years), the EEG evolution showed no statistically clear correlations with early therapies. The evolution into other seizure patterns also appeared independent of therapies. In our series less than a quarter eventually developed the Lennox-Gastaut syndrome. Controlled therapeutic protocols were adopted in an effort to resolve ongoing controversy about optimal treatment. Both groups were maintained, 135 136 C . T. LOMBROSO thoughout the therapeutic trial, on either antiepileptic drugs, on oral steroids alone, or on nonsynthetic ACTH alone, the latter followed in one subgroup by oral steroids also. Dosages were based on body surface or weight. Whenever cross-over or a change in the initial therapeutic regimen became necessary, the case was eliminated from the study. Clinical and laboratory tests were obtained at prefixed periods of time. For the short-term assessment ...

Recent Advances in the Pharmacotherapy of Infantile Spasms

“…This study included only cryptogenic patients. In a Class III study, early treatment initiation (\1 month following onset of symptoms) in 102 children with cryptogenic spasms, led to improved neurodevelopmental outcome [48]. Favourable cognitive outcome with shorter interval to treatment (\3 weeks [108], \4 weeks [109] and \4 weeks [42]) has also been seen in recent studies including patients with both cryptogenic and symptomatic spasms.…”

“…The common side effects of both drugs are irritability, sleep disturbances and drowsiness [27,39,40,48,66]. Both drugs also have severe side effects.…”

Longer duration of epilepsy and earlier age at epilepsy onset correlate with impaired cognitive development in infancy

“…Others have shown that control of infantile spasms is associated with better development during infancy and childhood [4], [6], [10], [12], [22], [23], [24] and [25]. In a previous report [11], more frequent spasms in children undergoing early surgical intervention were documented.…”

Efficacy and prognosis of a short course of prednisolone therapy for pediatric epilepsy

“…Our anecdotal experience has been that prednisolone is not as effective in patients with focal or diffuse brain lesions. Because of this, and because previous studies have shown that prednisolone is useful in treating cryptogenic epileptic encephalopathy including infantile spasms, 5,6 we decided to use the drug in patients presenting with normal neuroimaging data and without specific epilepsy etiologies. In the patients with Lennox-Gastaut syndrome (LGS) or early infantile epileptic encephalopathy (EIEE; called ''Otahara syndrome''), seizure attacks had occurred almost every day or at least more than four times a week.…”