Peri-Operative Management Of Maple Syrup Urine Disease: The Surgical Perspective

Maple syrup urine disease (MSUD) is a rare autosomal recessive inherited metabolic disorder. The main toxic amino acid leucine and its metabolites build up in the blood, precipitated by fasting, surgery and sepsis. This can result in confusion, seizure activity and potential cerebral oedema. We hope to raise awareness and understanding of the condition and its management for surgical teams who may encounter patients with MSUD. Medical therapy aims to rapidly reduce toxic metabolites by restricting dietary intake of plasma-branched amino acids and supplementing with amino acids mixtures free of leucine, isoleucoine and valine. Strict dietary management, restricting catabolism and promoting anabolism, and monitoring nutritional status are fundamental to long term growth, development and health maintenance. When considering surgery in a patient with MSUD, either electively or as an emergency, close monitoring is required. Advice from a metabolic expert is preferable. Fasting should be minimized where possible, the operation should be performed promptly and effectively and any sepsis should be treated. Daily monitoring of branched-chain amino acid levels and monitoring or nutritional and fluid intake are essential. Emergency feeding regimens, either orally, via nasogastric or total parenteral nutrition is required. Dialysis can filter toxic metabolites from the blood. When patients with maple surgery urine disease require surgery a multi-disciplinary team approach is required. Under the advice of a metabolic team, the surgical team needs to work closely with the anaesthetic and dietetic teams. With correct monitoring and nutritional support patients can make a full recovery following emergency or elective surgery.