Cryptogenic West syndrome: Clinical profile, response to treatment and prognostic factors

Abstract

Abstract Introduction West syndrome (WS) is an age-dependent epileptic encephalopathy in which the prognosis varies according to the, not always identified, underlying origin. Objectives To define the profile of cryptogenic (a least studied isolated sub-group) WS, in Spain. To study its outcome, response to different treatments, and to establish prognostic factors. Patients and methods The study included a review of the medical records of 16 patients diagnosed with cryptogenic WS during the period, 2000–2015. The mean follow-up time was 6.6 years, with a minimum of 2 years. Results The large majority (11/16) were male. The mean age at onset was 6 months, and 6/16 had a family history of idiopathic epilepsy. The first line treatment with vigabatrin had an electrical–clinical response in 5/16 patients, with the remaining cases responding to adrenocorticotropic hormone (ACTH). Almost half (44%) of the patients progressed to other types of epilepsy, with no difference between those treated with vigabatrin or ACTH. A greater number of adverse effects were obtained with ACTH, with no retinal involvement being observed with vigabatrin. The aetiological cause was found in 2/16. Being female, late onset, and early control of the hypsarrhythmia, were factors of a good prognosis. Conclusions The overall prognosis of cryptogenic WS was more serious than expected. Although the incidence of Lennox–Gastaut syndrome was low, the progression to focal epilepsy was the most common, with it appearing within the first 2 years of the diagnosis. The initial response to vigabatrin was lower than expected, but the long-term result was comparable to ACTH.