Clopidogrel-Associated Neutropenia: Case Report and Review of the Literature.

Clopidogrel is a second generation of thienopyridine, which has antiplatelet effect by inhibiting P2Y12 receptor. Hematologic adverse effect is very uncommon during clopidogrel use, but some cases of clopidogrel-associated neutropenia were reported in the past decade. Until now, there was no summary data to delineate the clinical course and safe alternatives of this event. We report 2 cases of clopidogrel-associated neutropenia and review other 10 case reports from 2000 to 2014. The median onset of neutropenia was 22 days, and the recovery time was 4 days after receiving granulocyte-colony-stimulating factor. Bone marrow studies in 6 cases all showed hypocellular or toxic damage. Six cases used cilostazol, prasugrel, or ticagrelor as safe alternatives. Closely monitoring blood cell counts is highly suggested in the first month after using clopidogrel. Newer P2Y12 inhibitors, especially ticagrelor, could be effective and safe alternatives if patients had a history of clopidogrel-associated neutropenia.