A 48-year-old man presented with a 10 kg weight loss and fever. On examination, there was digital ischaemia (figure 1), oedema of the lower extremities and absence of heart murmur. Laboratory investigation showed anaemia with a haemoglobin concentration of 96 g/L, thrombocytosis (995 Giga/L) and raised cardiac troponin T values (10 500 ng/L; normal 0–14). Howell-Jolly bodies were present on a blood smear (nuclear remnants found in red blood cells consistent with hyposplenism). Kidney function was normal with a serum creatinine level of 56 µmol/L, but the patient had haematuria on urine examination. PR3-ANCA was detected at 120 U/mL (normal 0–20). Cardiac investigations revealed no arrhythmias, endocarditis, intracardiac thrombus or coronary artery disease, but a 40% …