Teaching Case

A 62-year-old male patient who presented with attacks of frank haematuria after renal biopsy.

- An axial cut of a triphasic CT showing opacification of the renal vein during the arterial phase suggesting the presence of an arteriovenous fistula

- Diagnostic selective angiography of the left renal artery showing opacification of the renal vein during the arterial phase confirming the presence of an arteriovenous fistula

- Selective angiography after embolisation showing occlusion of the fistulous connection

- Background: Percutaneous image-guided renal biopsy has become the method of choice for obtaining renal tissue for diagnosis in most major medical centres. It is a relatively safe and easy procedure, but minor and major complications have been documented. [1] One of these complications is the creation of a traumatic arteriovenous fistula, which typically presents with attacks of frank haematuria. These attacks may be severe enough to cause a drop in the patient's haemoglobin level, or even haemodynamic disturbances requiring blood transfusions. [2] In these severe cases, endovascular embolisation is needed to occlude the fistula and stop the haematuria. [3]

- Clinical and Imaging Perspective: This 62-year-old male patient with chronic liver disease underwent a renal biopsy to diagnose the cause of acute kidney injury. He presented with an attack of frank haematuria three hours later, which did not require resuscitation. Ultrasound revealed a minimal perinephric collection and follow-up was recommended. He then presented with another attack of frank haematuria 6 hours later, and intravenous fluids and blood were given. Serial complete blood counts revealed a drop in his haemoglobin from 9.5 g/dL to 7 g/dL, and a triphasic CT of the abdomen and pelvis was done to exclude an enlarging retroperitoneal haematoma. CT revealed a minimal perinephric fluid collection, and the arterial phase showed opacification of the left renal vein, which is highly suggestive of an arteriovenous fistula. Selective angiography of the left renal artery was done showing opacification of the left renal vein during the arterial phase images, particularly in the lower pole of the kidney, which is diagnostic of an arteriovenous fistula. Super-selective catheterisation of the culprit artery was done, followed by embolisation. Follow-up images revealed occlusion of the arteriovenous connection, with absence of opacification of the renal vein during the arterial phase.

- Outcome: Follow-up revealed cessation of the haematuria

- Take Home Messages: Iatrogenic arteriovenous fistulas following renal biopsies typically present with frank haematuria. They appear as opacification of the renal vein during arterial phase images, whether on CT or angiography. Endovascular embolisation is an excellent option to occlude the fistula and stop the haematuria.