Soler NG, Aquino RS, Bencomo HA

Language: Spanish
References: 0
Page: 42-54
PDF size: 237.74 Kb.

ABSTRACT

Thrombocytopenia can have several causes, including the use of certain drugs. The mechanism behind drug-induced thrombocytopenia is either a decrease in platelet production (bone marrow suppression) or an increased destruction (immune-mediated thrombocytopenia). In addition, pseudothrombocytopenia, an in vitro effect, has to be distinguished from true drug-induced thrombocytopenia. A small number of epidemiological studies, differing largely in the methodology used, describe incidences in the magnitude of 10 cases per 1 000 000 inhabitants per year. The underlying mechanism of drug-induced immune thrombocytopenia is not completely clarified, but at least six different types of antibodies appear to play a role; hapten-induced antibody, drug-dependent antibody ("compound" or "conformational-dependent" antibody), GPIIb-IIIa inhibitors, drug-induced autoantibody, immune complex and heparin-induced thrombocytopenia. Targets for drug-dependent antibodies are glycoproteins on the cell membrane of the platelets, such as glycoprotein (GP) Ib/IX and GPIIb/IIIa. Diagnosis of drug-induced immune thrombocytopenia may consist of identifying clinical symptoms (bruising, petechiae, bleeding), a careful evaluation of the causal relationship of the suspected causative drug, general laboratory investigation, such as total blood count and peripheral blood smear (to rule out pseudothrombocytopenia), and platelet serology tests. Although drug-induced thrombocytopenia is a relatively rare adverse drug reaction, its consequences may be severe.