Sudden deepening of pigmentation during haemodialysis due to severe haemolysis.

A 37-year-old woman with chronic renal failure developed pain in the right flank during haemodialysis followed by rapid and dramatic deepening of pigmentation. Investigation indicated that the cause was severe haemolysis most probably due to mechanical damage to red blood cells passing through a stenosis in a dialysis blood line. Severe haemolysis should be suspected in subjects who suffer rapidly increasing pigmentation during dialysis. Such severe haemolysis should be recognized and treated rapidly since it may produce life-threatening systemic problems.