A Dilemma in Anticoagulant Therapy

Abstract

Editorial summary prepared for the online archive; the original print article was published without an abstract.

This clinical problem-solving case describes a 67-year-old man who presented with a high swinging fever, suprapubic and bilateral loin pain and the passage of gas in the urine. Investigation showed a colovesical fistula caused by a locally advanced colonic carcinoma with a single liver metastasis, complicated by ascending pyelonephritis and E. coli septicaemia. After antibiotic therapy, a defunctioning colostomy and pelvic radiotherapy, he developed pain and swelling of the left leg, and venography confirmed calf vein thrombi with an occlusive thrombus in the femoral vein.

Through a series of questions, the article reviews the clinical features of deep vein thrombosis (DVT), the risk factors present in this patient (age, recent infection, advanced pelvic malignancy, immobility after surgery, tumour breakdown after radiotherapy and a markedly raised plasma fibrinogen), and the relative merits of ultrasound and venography for diagnosis. It then discusses treatment with intravenous heparin followed by warfarin, and the ethical dilemma of anticoagulating a patient whose colonic tumour and fistula could bleed, with a vena caval filter as the alternative. After discussion with the patient and his family, anticoagulation was chosen, with the INR kept tightly at 2–2.5 for about three months. Tables summarise the clinical features, risk associations and differential diagnosis of DVT and the contraindications to anticoagulant therapy.