Malignant hyperthermia in a 16-day-old infant with congenital diaphragmatic hernia: a case report.

Malignant hyperthermia (MH) is a severe hypermetabolic disorder associated with dysregulation of calcium homeostasis and is triggered by inhalational anesthetics (isoflurane, sevoflurane, desflurane) and a depolarizing muscle relaxant (succinylcholine). We report the case of a 16-day-old infant undergoing laparoscopic surgery. The patient developed hyperthermia and hypercarbia with muscle rigidity. After the diagnosis of MH, dantrolene was administered with sufficient hydration. The patient was transferred to the pediatric intensive care unit for monitoring and treatment of acute renal injury due to myoglobinuria. Subsequently, two variants of the ryanodine receptor 1 (RYR1) gene were identified in the patient as the mutation point at c.1589G > A p.Arg530His and c.1841G > T p.Arg614Leu, which are known to be associated with MH. This was a rare case of MH in a 16-day-old infant that might be related to two RYR1 mutations inherited from the parents.