Thalidomide and thrombosis

BACKGROUND: Teratogenicity and neuropathy are the well known serious side effects induced by thalidomide. We describe 5 cases of thrombotic events occurring within a brief delay after the onset of thalidomide in a manner that suggests that thalidomide could have acted as a precipiting or as a starting factor in these events. OBSERVATIONS: Five patients including 4 patients with lupus erythematosus (1 discoid lupus, 1 subacute lupus and 2 systemic lupus erythematosus) and one patient with a severe atopic dermatitis, all without previous history of vascular events, developed an arterial thrombosis (2 cases) or a venous thrombosis (3 cases), severe in 4 cases, few days or weeks after the onset of thalidomide treatment (50 to 100 mg daily). DISCUSSION: All the patients had risk factors of thrombosis: the presence of antiphospholipids and/or anticardiolipin antibodies in lupus erythematosus patients and a trauma in the atopic case. However the absence of a previous story of thrombosis, its rapid occurrence after the onset of thalidomide and its severity are intriguing. In addition, recent studies demonstrate that thalidomide has various effects that would act, among other things, on angiogenesis. Thus, we think that a doubt exists on a negative effect of thalidomide in thrombosis risk factors patients and that this hypothesis has to be confirmed.