Heparin induced thrombocytopenia type II after the use of low-molecular-weight heparin. Case report and rewiew of the literature

Introduction. It has been suggested,that HIT-type-II can occur both after the use of low-molecular-weight and unfractionated heparin. The present study investigates the incidence of HIT-type-II after the use of low molecular weight heparin by reviewing the literature and describes one own case. Case report. We observed in a 72 year old female patient a HIT-type-II, who received low molecular weight heparin (Clexane 40 o.a.d) after the implantation of an endo-prothesis as thrombosis prophylaxis. This occurred on the 9(th) postoperative day. One year later we performed a second endoprosthesis operation of the contralateral site without complications. With the known HIT-type-II, diagnosed the year before, we used hirudin (Refludan) for thrombosis prophylaxis. Result. A critical view on the international literature revealed only a few cases, where a HIT-type-II was caused by the use of low molecular weight heparin. The incidence seems to be much lower than correlated to the use of unfractionated heparin. Conclusion. It is possible to suffer from a HIT-type-II after low molecular weight heparin. This study confirms the suspicion that the incidence of a HIT-type-II after low molecular weight is lower than after unfractionated heparin. Therefore the further use of unfractioned heparin for thrombosis prophylaxis has to be questioned and low molecular-weight heparin should be preferred.