Fatal recrudescence of malignant hyperthermia in an infant with Moebius syndrome.

Background And Objectives: Malignant hyperthermia (MH) is a pharmacogenetic skeletal muscle disorder characterized by a hypermetabolic state after anesthesia with succinylcholine and/ or volatile anesthetics. Various neuromuscular syndromes are associated with susceptibility; however, Moebius syndrome has not been reported. Dantrolene is the drug of choice for treatment. Recurrence may occur in up to 20% of cases after the initial event treatment.

Case Report: Male infant, fi rst twin, 7 months old, weighing 6.5kg and presenting with Moebius syndrome was admitted for clubfoot repair. The patient had MH after exposure to sevoflurane and succinylcholine, which was readily reversed with dantrolene maintained for 24 hours. Ten hours after dantrolene discontinuation, there was recrudescence of MH that did not respond satisfactorily to treatment, and the patient died.

Discussion: Musculoskeletal disorders in children are associated with increased risk of developing MH, although Moebius syndrome has not yet been reported. Dantrolene is the drug of choice for treating this syndrome; prophylaxis is indicated during the fi rst 24-48 hours of the episode onset. The main risk factors for recurrence are muscular type, long latency after anesthetic exposure, and increased temperature. The child had only one risk factor. This case leads us to reflect on how we must be attentive to children with musculoskeletal disease and maintain treatment for 48 hours.