Hot water epilepsy with cerebral lesion: a report of five cases with cranial MRI findings.

Hot water epilepsy (HWE) is included in the reflex epilepsies. Although, in general, not common, HWE is concentrated in certain regions of the world. Different bathing habits and genetic factors may be responsible for the high incidence of HWE in these regions. However, the exact pathogenesis of HWE is not known. The facts that complex partial seizures are the most common clinical presentation and EEG recordings show an epileptic focus in the temporal lobe suggested the presence of a structural lesion in the temporal lobe. To our knowledge, however, there were no demonstrable structural changes on MRI and CT scans except in a few case reports. Here, we describe an additional five cases of HWE having an intracranial pathology, for example, hippocampal sclerosis, dysplasia, and a huge cystic lesion. We believe that investigations with new detailed neuroimaging techniques, in addition to experimental and clinical studies, might help us to understand the mechanism of this reflex epilepsy.