Malignant hyperthermia is a rare autosomal-dominant genetic syndrome of dogs characterized by hyperthermia.
Complications of this syndrome may be fatal in some cases due to extensive rhabdomyolysis, generalized skeletal muscle contracture, cardiac dysrhythmia and acute renal injury, often triggered by exposure to fermented hops, succinylcholine or volatile anesthetic agents, particularly halothane.
Clinically affected dogs usually present with hyperthermia (> 40.00C), restlessness, panting, vomiting, signs of abdominal pain, seizures, tachycardia, tachypnea, increased carbon dioxide production, increased oxygen consumption, acidosis, muscle rigidity and rhabdomyolysis. Symptoms are all related to a hypermetabolic response.
A differential diagnosis would include other causes of hyperthermia including sepsis, exercise-induced collapse, polyneuropathy, myokymia, ivermectin toxicity, tetanus, lasalocid poisoning, hyperthyroidism and pyrexia.
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