Hot water epilepsy.
Seizures accelerated by a specific sensory stimulus are related to reflex epilepsy. HWE is accelerated by the purpose of bathing in hot water poured over the head, and is also variably is known as water-immersion epilepsy or bathing epilepsy. It is from southern India that a large number of cases of HWE have been reported, The exact etiopathogenesis of this type of epilepsy is not clear, but several factors including genetic factors, environmental factors, consanguineous marriages, and habit of taking bath with high-temperature water have been postulated as probable reasons. Reports from our cento suggest that the cohort of patients with HWE is mostly from two adjoining districts, viz. Madhya-Mysore belt in Karnataka state of South India. HWE was reported to account for 3.6-3.9% of all epilepsy cases in this part of India. Triggering factors were mainly temperature of the water and contact of water on the scalp. Studies have shown a strong family history of epilepsy in these subjects from India.
Even though the exact mechanism of HWE is not clear, many theories have been proposed to explain the peculiar nature of seizures. Earlier, Satish Chandra et al. had postulated that patients with HWE probably have an aberrant thermoregulatory system and are probably sensitive to a rapid rise in temperature. The impaired sympathovagal balance is observed in HWE, characterized by increased sympathetic activity and reduced parasympathetic activity in patients with HWE. The hypothalamus is involved in both the pathogenesis of HWE and autonomic regulation. Intermittent therapy with clobazam, 1-1½ h before hot water head bath, is the method of treatment for this type of epilepsy. AEDs are required only if HWE is associated with non-reflex seizures.