Introduction:

The West Delphi group proposed a classification of infantile spasms (IS): IS in cluster with  Hypsarhythmia (West syndrome), IS in cluster  without hypsarrhythmia; IS single-spasms variant (ISSV) with hypsarrhytmia and ISSV without hypsarrhytmia.

Purpose:

To classify the IS registered in the video EEGs according to the Delphi West group proposal and analyze outcome.

Methods:

Observational retrospective study including 33 video-EEGs, between January 2010 and September 2013.

Results:

median age:6.1 months, 19 (57.5%) were female. According to the classification, we observed: 14 (42.4%) had West syndrome (WS), 10 (30.3%) IS in cluster without hypsarrhythmia, 7 (21.2%) ISSV with hypsarrhythmia,  and 2 (6%)ISSV without hypsarrhythmia.

24 patients had symptomatic epilepsy and 7 cryptogenic.

EEG findings: 18 (63.6%) presented hypsarrhythmia, 24 (81.8%) multifocal paroxysms and 6 unifocal paroxysms.  Fourteen of the 18 (77.7%) patients with hypsarrhythmia, had symptomatic epilepsy. 
We analyzed 31 patients. 8 (25.8%), were preterm. 23 (74,2%) had a normal neurological exam before seizures started, 15 (49.5%)  worsened developmental delay.  One patient died.The median duration of IS was 4 months (IQR 1,5-9), 4 months in patients with hypsarrhythmia and 6.5 months, without hypsarrhythmia.

Outcome: 13 developed  refractory epilepsy, 10/13 had symptomatic epilepsy and 10/13 had hypsarrhythmia.

12 out of 17 (70,5%)  patients with hypsarrhythmia and 3/12 (25%) patients without hypsarrhythmia lost developmental skills. (p: 0.01).

Conclusions:

We observed a high frequency of patients with West syndrome and ISSV without hypsarrhythmia. Patients with or without  hypsarrhythmia developed refractory epilepsy associated to developmental delay, being more frequent in patients with hypsarrhythmia.