[Heparin-induced thrombocytopenia with unfractionated heparin. A prospective study of inpatient treatment of internal medicine patients]

To investigate the influence of unfractionated heparin on heparin-induced thrombocytopenia (HIT) type II.In 162 patients with internal diseases treated therapeutically of prophylactically with unfractionated heparin (heparin sodium, heparin calcium), we carried out a prospective study to determine the incidence of HIT type I and II. 55.6% of the patients were female (n = 90) with an average age of 76.5 years (range: 25 to 96 years) and 44.4% male (n = 72) with an average age of 67.5 years (range: 17 to 93 years). A platelet count was taken regularly before the start of heparin treatment, on the first day of treatment and then every second day from day 5 to 20. Whenever HIT II was suspected, an HIPA test was performed.Type I HIT occurred in 10%, type II in 3% of the cases. Two of the 5 patients with type II developed severe thrombotic complications.In view of the high incidence of HIT, regular platelet counts should always be carried out in patients receiving heparin treatment.