Shapiro's syndrome: Defining the clinical spectrum of the spontaneous paroxysmal hypothermia syndrome.

Shapiro Syndrome (SS) is a rare condition of spontaneous periodic hypothermia, corpus callosum agenesis (ACC) and hyperhidrosis which can occur at any age. The variant form refers to the phenotypic SS without ACC. We reported the case of SS variant on a 4-year-old boy who presented from his first year frequent episodes of hypothermia lasting 2-3 h with core rectal temperatures <35 °C. In order to understand the characteristics of this rare syndrome we searched all the cases present in literature. Fifty-two cases of SS were found in literature. Among all clinical signs, paroxysmal hypothermia seems to be the hallmark of both typical and variant SS. ACC is reported only in 40% of cases of SS. Hyperhidrosis, another hallmark of SS, was present in only 42.3% of the cases and mainly in adult onset. The presence of SS in siblings of different genders suggests an autosomal recessive inheritance model, however a gonadic mosaicism responsible for an autosomal de novo mutation cannot be ruled out. From our review of well documented cases of SS, we conclude that only the episodic and spontaneous paroxysmal hypothermia should be considered the defining hallmark of typical and variant SS. This can be important to define the clinical manifestation of SS improving the early diagnosis.