West syndrome: etiologic issues

Abstract

Introduction:West syndrome (WS) is characterized by spasms in clusters, hypsarrhythmia and developmental stagnation or regression. The objective of this study is to know the etiologic distribution of WS in our area and changes over time.

Method: Retrospective study of 20 children with WS diagnosis from 1993 to 2001. Causes are analyzed, and diagnostic methods used, therapy, and progress are described. Results are compared with other study made from 1975 to 1986 in the same hospital.

Results: Ratio male: female of 1.5:1. The mean age of beginning of the spasms was 7.4 months, with a diagnosis delay of at least one month in 60% of the patients. 16 symptomatic cases (11 of prenatal origin, 4 perinatal and 1 postnatal), 3 cryptogenic and 1 idiopathic were identified. The hypsarrhythmia and the spasms disappeared in all patients, but half of symptomatic cases persisted with other types of seizures. 3 exitus were recognized, all of them symptomatic. The rate of symptomatic cases was significantly higher in the 1993-2001 period (16/20, 80%) than in 1975-1986 (15/30, 50%).

Conclusions: New technologies help to identify a bigger proportion of patients with SW as symptomatic. It still exists an important delay in the diagnosis, because of the confusion between spasms and other paroxystic non epileptic episodes. In presence of a clinic suspicion, an EEG must be done for discarding or confirming hypsarrhythmia. The pre-existing lesions condition the bad progress of symptomatic WS.