More than one self-limited epilepsy of childhood in the same patient: A multicenter study.

Objective: We describe the evolution of the electroclinical picture of patients with different types of self-limited epilepsy of childhood (SLEC) occurring at the same or at different times with or without atypical evolutions as well as patients with SLEC associated with childhood absence epilepsy (CAE).

Material And Methods: A multicenter, retrospective, descriptive study was conducted evaluating patients with SLEC who had focal seizures of different types of SLEC including atypical evolutions as well as SLEC associated with absence epilepsy seen at eight Argentinian centers between April 2000 and April 2019. Of 7705 patients with SLEC, aged between 2 and 14 years (mean, 7.5 years), of whom 2013 were female and 5692 male (ratio, 1:2.8), 5068 patients had SLECTS, 2260 patients had self-limited childhood occipital epilepsy Panayiotopoulos type (SLE-P), 356 had self-limited childhood occipital epilepsy Gastaut type (SLE-G), and 21 had self-limited epilepsy with affective seizures (SLEAS). Electroclinical features typical of more than one SLEC syndrome were recognized in 998 (13 %) children.

Results: We recognized three well-defined groups of patients. The most frequent association was SLE-P and SLECTS, the paradigmatic type, but associations of SLE-P and SLE-G, SLECTS and SLE-G, and SLEAS and SLE-P or SLECTS were also recognized. The second-most-common association was SLEC and an atypical evolution. In this group, the most frequent combination was SLECTS with its atypical evolution, opercular status epilepticus, epileptic encephalopathy with continuous spike-and-waves during slow sleep, or Landau-Kleffner syndrome. SLE-P and SLE-G associated with an atypical evolution were also identified. The third, less-frequent group had SLECTS, SLE-P, or SLE-G associated with CAE. These cases support the concept that the different types of SLEC are part of a self-limited childhood seizure susceptibility syndrome.

Conclusion: Our study demonstrated that 13 % of our patients with SLEC have with different types of SLEC occurring at the same or at different times with or without atypical evolutions - i.e. CSWSS - as well as patients with SLEC associated with CAE, supporting the concept of the self-limited childhood seizure susceptibility syndrome.