Acute renal failure and multiple sites of ischaemia: what is the unifying diagnosis?

A 67-year-old man presented to the Accident and Emergency department in September 2004 with cough and sudden shortness of breath. In 2002, he had suffered a left occipital infarct that presented as a transient ischaemic attack. In 2003, he sustained bilateral cerebellar infarcts that left him with residual tremor and ataxia (Figure 1). He took regular aspirin, clopidogrel and simvastatin for secondary prevention of cerebrovascular events. On presentation his oxygen saturation was 79%, heart rate 120/min, respiratory rate 40/min and blood pressure 155/112 mm Hg. Chest auscultation revealed crackles and decreased air entry at the left base. Examination of the heart and abdomen was normal. He had type 1 respiratory failure (pO2 6.1 kPa, pCO2 4.5 kPa). Full blood count, creatinine (75 μmol/l), electrolytes and clotting were normal. A chest radiograph showed left basal shadowing and prominent hila. He was treated with heparin and aspirin for suspected pulmonary embolism; CT pulmonary angiography was performed (Figure 2). Two days later he developed nausea, vomiting and a sudden sharp constant pain in the left flank passing into the iliac fossa, not relieved by morphine. Abdominally, he was tender in the left hypochondrium and iliac fossa. There were no urinary symptoms. Concurrently, there was an abrupt rise of urea to 16.6 mmol/l and creatinine to 450 μmol/l. He underwent abdominal CT scan and echocardiography (Figures 3, 4).