A severe disorder with characteristics of muscular contractions at birth, intermittent hyperthermia, facial abnormalities and camptodactyly. Since the first description of the disease in 1996, it has been described in less than 30 patients from 13 Italian (mainly Sardinian) families. Extensive paroxysmal muscular contractions in the face (resembling neonatal tetanus) develop after minimal stimuli. All patients described to date displayed facial anomalies, including a large face, chubby cheeks, a broad nose with anteverted nostrils and long philtrum and bilateral camptodactyly. Early in the neonatal period continuous hyperthermia develops (unrelated to infectious agents). Mutations in the CRLF1 gene are causative. Belongs to a group of conditions with overlapping features, including cold-induced sweating syndromes and Stüve-Wiedemann syndrome. The disease is transmitted as an autosomal recessive trait.