Hot water epilepsy: Clinical and electroencephalographic features of 25 cases

The aim of this study was to analyze the clinical and electroencephalographic findings for 25 patients with hot water epilepsy. Personal and family history, neurological state, age at onset and types of seizures, provoking factors, bathing habits, EEGs, and neuroimages were all reviewed. Age at onset of seizures ranged from 6 months to 37 years. Twenty patients had complex partial seizures. Eight patients had spontaneous seizures as well; one was a typical case of idiopathic photosensitive occipital lobe epilepsy. One patient described an episode interpreted as nonconvulsive status. In our study group, the pouring of the water over the head and the temperature of the water were the most common triggering factors. A special kind of soap and entry of water into the mouth were determined to be unusual triggering factors. Interictal EEGs revealed epileptogenic abnormalities located over the temporal regions in nine patients. Seventeen patients underwent neuroimaging, mostly cranial magnetic resonance imaging. One had right mesial temporal sclerosis and one cortical atrophy; the others had normal findings. Sixteen patients received antiepileptic drugs, mainly carbamazepine, and remained seizure-free. The high rate of epileptogenic abnormalities localized in the temporal region and the complex partial seizures observed in most of our patients indicate the considerable role of the temporal lobe in hot water epilepsy.