1. A 33-year-old woman with systemic lupus erythematosus who has developed livedo reticularis suffers an unprovoked deep vein thrombosis in her left leg. Her coagulation screen shows a PT of 16 s (12–14) and an APTT of 40 s (26–33.5).The test most strongly indicative of your suspected diagnosis would be:

2. A 25-year-old man presents with abdominal pain and diarrhoea but without any passage of blood. He is hypertensive. His FBC shows a normal Hb and platelet count but he has a neutrophil leucocytosis with a left shift. Three days later he becomes anuric, his creatinine rises, his platelet count falls to 35 × 109/l and schistocytes are found in his blood film. A test on stool for Shiga toxin is negative. ADAMTS13 is assayed at 75% (50–150%). The most likely diagnosis is:

3. A 55-year-old man is reviewed in pre-admission clinic prior to a hernia repair. He reports that he bled badly after tonsillectomy as a child and required blood transfusion. A coagulation screen shows PT 10.7 s (9.6–11.6) and APTT 63 s (26–32). Thrombin time is normal.The most likely explanation is:

4. A 55-year-old man with a recent diagnosis of carcinoma of the lung and pulmonary embolism has been prescribed warfarin. He presents with major gastrointestinal bleeding and an INR of 4.5. Optimal management, in addition to red cell transfusion as indicated, is: