Malignant Hyperthermia: A Study of an Affected Family

A case of malignant hyperthermia is described. The possible occurrence of similar susceptibility among members of the patient's family was investigated by measuring their serum creatine phosphokinase activities. Patients who carry the trait have no presenting clinical stigmata and there is no specific screening test to detect its presence. The condition is more common than is generally believed. It is suggested that it would be worthwhile to reassess the diagnosis in patients who have died under anaesthesia from obscure causes, to consider the possibility that some of these may have been cases of malignant hyperthermia, and to study the serum creatine phosphokinase activities of their surviving relatives. Malignant hyperthermia is a condition characterized by rapidly developing fever and often by skeletal muscle rigidity in association with general anaes-thesia. It is genetically determined (Denborough et