ABSTRACT
Mutations in the X-linked gene cyclin-dependent kinase-like 5 (CDKL5) have been detected in patients presenting with seizures in the first few months of life and Rett syndrome features. Twenty-seven cases have been detected to date. Generalized intractable seizures, as infantile spasms, and generalized tonic-clonic seizures and myoclonic seizures characterize the clinical picture of CDKL5 mutations. Here we report on a patient who presented with sleep-related hyperkinetic seizures. Our observation and review of the literature suggest that a broader polymorphic electroclinical pattern with both generalized and focal seizures may occur in patients with CDKL5 mutations. A screen for CDKL5 mutations is useful in patients, mainly females, with a history of early onset intractable seizures and becomes mandatory when idiopathic infantile spasms and/or atypical Rett syndrome features are also present.