Spontaneous hypothermia: a series of ten cases, place of Shapiro's syndrome

SUBJECT: Hypothermia (defined as a core temperature lower than 35 degrees C) may result from accidental causes (exposure to cold, drug intoxications), from endocrine disorders (hypothyroidism), or from central or peripheral neurological disease. Among the causes of spontaneous hypothermia, the place of spontaneous periodic hypothermia or Shapiro's syndrome, of which less than 50 cases in children or adults have been reported, remains unclear. METHODS: Case series of spontaneous hypothermia in adults, from a register of the French Society of Internal Medicine (SNFMI). RESULTS: The ten collected cases of spontaneous hypothermia are heterogeneous. In half of the cases, an often ill-labeled psychiatric illness and/or epilepsy and/or anti-psychotic medication were found contributive. Only 5 cases at best seem to conform to the pattern of spontaneous periodic hypothermia or Shapiro's syndrome (in which agenesis of corpus callosum is typically found). In such cases, the episodes of hypothermia start with profuse hyperhidrosis suggesting a paroxystic reset of the hypothalamic thermostat with a lower temperature set point. In none of the cases was found a significant encephalic lesion. None of the treatment trials with anti-epileptics or cyproheptadine were found useful. Spontaneous hypothermia, whether periodic or not, seems to have an unpredictable course, with long periods of remission, and a benign long-term outcome. CONCLUSIONS: Spontaneous hypothermia is a symptom of likely multifactorial etiology. Even in cases conforming to the definition of Shapiro's syndrome, central nervous system anomalies are not unequivocal. No specific treatment for spontaneous hypothermia, whether periodic or not, can be recommended in the current state of knowledge.