Reversal of life-threatening bleeding with protamine sulfate in a patient with plasma cell leukemia

Plasma cell disorders, such as multiple myeloma, can cause numerous derangements of hemostasis. In this case report, we present a life-threatening coagulopathy in a patient with progressing multiple myeloma in which the antibody-producing heparin-like activity is a free light chain. The patient's bleeding was successfully treated using protamine sulfate, which then allowed treatment of her plasma cell leukemia. In the literature, other authors have reported similar patients who have responded to protamine sulphate either in vitro or in vivo, providing further evidence for the role of protamine sulfate in the reversal of coagulopathy and resolution of bleeding diathesis. Standard treatments of transfusion with fresh frozen plasma and cryoprecipitate are likely to be ineffective in life-threatening bleeding related to this mechanism (heparin-like effect), and it is essential that treating physicians are aware of this potential mechanism of bleeding in their patients.