Hemolysis in hypertensive disorders of pregnancy.

The hemolysis markers LDH, haptoglobin, bilirubin (serum, urine), urobilinogen (urine), fragmentocytes and free hemoglobin were compared in 166 patients with various degrees of hypertensive disorders of pregnancy and 179 nonhypertensive pregnant controls in a weekly screening program. Early recognition of hemolysis was limited to a period of 1 week before the actual delivery date. In the diagnostic sensitivity, haptoglobin and to a lesser degree unspecific LDH were clearly superior to the other hemolysis parameters. A decreasing platelet count also has to be taken as an indicator of impending hemolysis. Subclinical hemolysis was associated with poorer fetomaternal outcome. With the aid of haptoglobin, LDH and thrombocytes, an incipient HELLP syndrome could be recognized 1-2 days before the complete clinical picture became apparent.