Biopsy-Related Renal Allograft Arteriovenous Fistulas

Abstract

Introduction Percutaneous renal biopsy is the tool to evaluate and manage renal allograft dysfunction. Like all other invasive procedures, percutaneous biopsy has its own risk of complication. Vascular injuries such as arteriovenous fistula (AVF), pseudoaneurysm or arteriocalyceal fistula may result in symptoms that require endovascular intervention. We share a case series of 5 arteriovenous fistulas of the renal allograft resulting after percutaneous biopsy. Materials and Methods 4 patients with no symptoms were diagnosed for AVF during their routine Color Doppler ultrasound (CDU) control. One patient who presented with massive haematuria underwent emergent transplant renal angiography and the diagnosis was AVF. 4 of 5 patients had received kidney transplantation in our hospital and the other one was operated in another hospital. This patient was referred to our institution for the treatment of AVFs which was diagnosed by CDU in the other hospital and before admission to our centre, he had undergone multiple renal allograft biopsies in another hospital. the other 4 patients were operated in our hospital and are being followed-up since. 4 of 5 post-biopsy renal allograft AVFs underwent embolization. One patient is being followed-up medically because of the low flow in the AVF and has not received intervention yet. 4 of 5 were male. The mean age of the patients was 32.2 years (range 8-52). CDU was performed for all 5 patients. Transplant renal arteriography was performed for the 4 patients who underwent embolisation. One of the patients had 2 pseudoaneurysms and 2 AVFs in the transplanted kidney. Superselective embolization using a microcatheter was performed with 2-3-4 mm coils for 3 patients and spongostan for 1 who presented with hematuria and vesicle haematoma. Results Control angiography after embolization revealed that all AVF’s and 2 pseudoaneurysms were successfully occluded. No procedure-related complications occurred. Conclusion Percutaneous renal biopsy is a convenient method to diagnose allograft rejection. Vascular complications such as AVFs and pseudoaneurysms after renal biopsy are not rare, and they usually spontaneously resolve. Patients can be symptomatic or not. The diagnosis can be made easily with CDU. The patients who are symptomatic can be treated successfully by transarterial embolization. The success rate of transarterial embolization is almost 90%. The treatment choice for cases which do not respond to embolization is surgical treatment like arterial ligation, partial or total nephrectomy. If no spontaneous regression happens, the option should be embolization therapy for asymptomatic patients to prevent late onset complications. Symptomatic AVF’s should be treated by transarterial embolization, which is effective and safe. Asymptomatic patients can be followed-up for spontaneous resolve. If it does not resolve spontaneously, transarterial embolization should be the treatment of choice.