Rhabdomyolysis with severe hypernatremia.

Three children with severe hypernatremia presented with profound generalized weakness and biochemical evidence of rhabdomyolysis and myoglobinuria. These findings in combination have not been previously reported, to our knowledge, in children with severe hypernatremia. Unusual complications included respiratory failure in one child and cardiac arrhythmias in two children. All three children had acute renal insufficiency; one required peritoneal dialysis.