Purpura fulminans (PF) is an infrequent complication of varicella characterized by the progressive development of purpuric or painful ecchymotic lesions associated with biochemical alternations typical of consumption coagulopathy. Activation of coagulation is due to a marked and prolonged decrease in protein S, which is probably secondary to the formation of antiprotein S antibodies. The mechanism responsible for the synthesis of these autoantibodies is unknown. We present three cases of postvaricella PF and review the clinical and biochemical characteristics of this entity, as well as current diagnostic and therapeutic recommendations.