Vascular purpura induced by dalteparin

A case of vascular purpura after injection of dalteparin in a patient with lung cancer complicated by phlebitis is reported. The purpura resolved afte r stopping dalteparin while no other cause of purpura was demonstrated. The positive intradermal reaction to dalteparin suggested a hypersensitivity m echanism, supported by a history of prescription prior to the dalteparin cu taneous adverse drug reaction. Dalteparin was replaced by a synthetic hepar inoid, lomoparan, with no adverse effects. This case, very rarely described , emphasizes the need for increased surveillance of low molecular weight he parins. These molecules, increasingly prescribed In thromboembolic disease, are responsible for bleeding and immunoallergic adverse effects, especiall y thrombocytopenia, but also cutaneous adverse drug reactions, as in the ca se described here. Synthetic heparinoids could constitute an alternative tr eatment.