Abstract: | A 15-year-old male dog with chronic hematuria was found to have prolonged activated partial thromboplastin time. Results of plasma coagulation assays indicated a deficiency of prekallikrein, a plasma protein that modulates the rate of activation of factors XI and XII in the intrinsic clotting system. Patients with prekallikrein deficiency rarely have manifestations of hemorrhage. The hematuria was the result of a renal transitional cell carcinoma. |