West syndrome--The University of Hong Kong experience (1970-2000)

To study the clinical pattern of West syndrome (WS) in a university based hospital.

The database of children seen in the Epilepsy Clinic of Queen Mary Hospital and Duchess of Kent Children's Hospital during a 30-year period (1970-2000) was reviewed.

A total of 105 cases had WS (1.9%). The number of new cases of WS admitted per year ranged from one to eight. The range of annual incidence of WS to newly diagnosed epilepsy was 0.8-4.8%. The etiology included idiopathic (N=19, 18%), cryptogenic (N=23; 22%), symptomatic (N=56; 53.3%) and unknown (N=7; 5.7%). Adrenocorticotropic hormone (ACTH) and/or prednisone were given to 42 children (40%). Most were effective in controlling WS on an all-or-none fashion. Seizure outcome included 12 with remission, persistent in the same form in two and persisting but changed to another form in the rest. Neurological outcome at the last follow up in 2000 December included multiple disabilities (N=16), cerebral palsy (N=22), mental retardation (N=94) and Lennox-Gastaut syndrome (N=13). We analysed the following risk factors in relation to poor outcome: age of onset, age of presentation, time lag before treatment, etiology, family history of epilepsy and hormonal treatment. Only etiology of WS has a positive correlation with poor outcome (P<0.0005).

WS is an uncommon epileptic syndrome. The majority had poor outcome, especially those with causes identified. Infantile spasm is a specific epileptic phenomenon in a maturational stage of a child when heterogeneous disorders can present with the same clinical epileptic and electroencephalographic phenomenon.