A Case of Primary Erythermalgia, Wintry Hypothermia and Encephalopathy

Abstract

Primary erythermalgia is a rare neuropathy characterized by attacks of burning pain and redness in the extremities in response to warm stimuli. We describe here a boy with erythermalgia whose painful attacks began in infancy. We found a novel mutation of SCN9A, which is a responsible gene for primary erythermalgia in this case. In his teens, he developed wintry hypothermia with resultant neurological dysfunction and recurrent pneumonia. During the course of pneumonia, he had transient encephalopaty with a reversible lesion in the splenium of the corpus callosum. In addition to excessive cooling, a defect in central thermoregulation may have caused hypothermia in this patient.

A case of primary erythermalgia with encephalopathy

“…To date, the pathomechanism of this erythermalgiaassociated encephalopathy remains obscure. Two cases of primary erythermalgia associated with encephalopathy have been reported previously [6,9]. One of these [9] was very similar to ours: a 15-year-old boy who developed hypothermia, somnolence, and ataxic gait.…”

“…Two cases of primary erythermalgia associated with encephalopathy have been reported previously [6,9]. One of these [9] was very similar to ours: a 15-year-old boy who developed hypothermia, somnolence, and ataxic gait. However, in this case, the brain MRI revealed increased signal intensity in the splenium of the corpus callosum, which is in contrast to our normal MRI findings, although the EEG was very suggestive of encephalopathy.…”

“…Encephalopathic symptoms associated with primary erythermalgia have previously been reported but are not well understood [9].…”

Inherited Pain

“…Inherited (or primary) erythromelalgia (IEM, 2 MIM 133020) is characterized by episodic reddening of and burning pain in the hands and feet (2). Its onset is during adolescence, and patients often resort to submerging the limbs in ice-cold water for relief, which can lead to further complications like hypothermia, tissue damage, and wound infections (3,4).…”

Between fire and ice: refractory hypothermia and warmth-induced pain in inherited erythromelalgia

“…Although significant skin injury, as seen in this patient, has been reported in patients with IEM from aggressive cooling, the development of hypothermia is rare and its pathophysiological basis not understood [14][15][16] The overuse of cooling devices in our patient or the overuse of ice in the patient described by Seneschal et al likely contributed to the hypothermia (Solé, personal communication). 14 The father of this patient was reported to be persistently hypothermic, with usual temperature of 35°C (Solé, personal communication), raising the possibility of a generalised disorder of thermoregulation.…”