Ictal kissing: occurrence and etiology.

Ictal kissing is a rare semiological manifestation in patients with epilepsy. We tried to estimate its occurrence and characterize the underlying etiology. We retrospectively reviewed all video-EEG reports from Jefferson Comprehensive Epilepsy Center over a 12-year period (2004-2015) for the occurrence of the term "kiss". We then searched the electronic database PubMed on September 21, 2016 using the following search terms in the English language: "ictal" OR "seizure" OR "epilepsy" AND "kiss" OR "kissing". Relevant original studies were included. During the study period, 5133 patients were investigated in our epilepsy monitoring unit. One patient (0.02%) had one episode of documented ictal kissing. He had drug-resistant right mesial temporal lobe epilepsy. In total, five studies met the criteria for inclusion in the review. These studies described nine patients with drug-resistant focal epilepsy and ictal kissing behavior. Six out of ten patients with ictal kissing had hippocampal sclerosis. We add to the literature on ictal kissing by providing additional information on its frequency and etiology. The most common underlying etiology for ictal kissing is hippocampal sclerosis. However, this semiological ictal phenomenon is not pathognomonic for any etiology or localization.