PROS1 and Disseminated intravascular coagulation: The deficiency can be acquired under conditions like septic shock, disseminated intravascular coagulation, acute respiratory distress syndrome, postoperative states, liver diseases, pregnancy, oral contraceptive pill use, human immunodeficiency virus infection and chemo-therapy for breast cancer.8 The initial presentation of prethrombosis in this patient was related to protein S deficiency.