[Acute rhabdomyolysis in the child]

Rhabdomyolysis results from muscular fibre lysis with release of cellular contents (myoglobin, enzymes, electrolytes) into the plasma. Traumatic (crush syndrome) and non-traumatic rhabdomyolysis have been mostly reported in adults. Traumatic rhabdomyolysis are mostly due to ischemic and reperfusion injuries. Non-traumatic rhabdomyolysis include several factors: muscular compression (comas), cytotoxic injury (infections and poisonings), ischemia (shock, cardiorespiratory arrest) or excessive muscular activity (seizures, strenuous exercise). The main etiologies reported in children are: anoxic-ischemic encephalopathy (including sudden infant death and life threatening events); electrolyte disorders; severe hyperthermia; poisonings; hereditary myopathies. Non-traumatic rhabdomyolysis must be suspected in these circumstances, requiring blood creatinine phosphokinase measurements. Indeed, clinical signs are inconstant and non-specific, and functional signs are difficult to appreciate in children. During the initial phase, the main risk is arrhythmias secondary to hyperkalemia. The two main complications are the compartmental syndrome leading to irreversible vasculo-nervous injuries and acute renal failure. Treatment of traumatic and non-traumatic rhabdomyolysis includes correction of hyperkalemia, active fluid loading in order to prevent acute renal failure and alkalinisation. Prognosis of rhabdomyolysis relates to the aetiology and the presence of acute renal failure.