Angiographic embolization in patients with renal allograft arteriovenous fistula

Arteriovenous fistulas after ultrasound-guided needle biopsy of kidney allografts and treatment outcomes after transcatheter embolization: A single-center experience in Japan

BACKGROUND

Arteriovenous fistula (AVF) is one of the vascular complications after allograft biopsy, and their reported incidence rates range widely. Transcatheter embolization (TE) is a common AVF treatment in kidney allografts. However, information on AVF incidence and features and TE outcomes in Japanese kidney transplant (KT) recipients is lacking.

METHODS

This study investigated 270 protocol or clinically indicated kidney allograft biopsies in 129 KT recipients during 2010-2016 at a single-center using standardized methods (16-gauge needle and ultrasound guidance). We recorded the incidence and clinical features of AVF using currently recommended standardized methods of allograft biopsy and TE outcomes regarding allograft function up to 12 months after the procedure in Japanese KT recipients.

RESULTS

AVF incidence was 2.6% (seven cases). The time from biopsy to AVF diagnosis was 7 (median, interquartile range: 5-117, range: 1-318) days. The time from biopsy to AVF diagnosis was significantly shorter in symptomatic cases (gross hematuria) than in asymptomatic cases (median 6 vs. 117 days, p = 0.034). Symptomatic patients underwent TE within a shorter time (0-6 days) than asymptomatic patients (25-104 days). There were no complications, and allograft function was stable up to 12 months after TE despite using contrast media and partial renal infarction.

CONCLUSIONS

AVF does occur in certain probabilities. AVF formation can occur without apparent bleeding and exist for a long time after allograft biopsy. TE is a safe and immediate treatment for AVF in kidney allograft.

Aneurysmal dilatation associated with arteriovenous fistula in a transplanted kidney after renal biopsies

AVF is a known complication of renal biopsy in both native and transplanted kidneys. A 20-yr-old woman with bilateral hypoplastic kidneys due to branchio-oto-renal syndrome had received living-donor renal transplantation from her father at the age of 11. She had undergone allograft renal biopsies six times and all puncture sites were at the lower pole of her kidney from the first to the fifth biopsy. AVF with aneurysmal dilation (30 mm) had developed at the puncture site after the fifth biopsy. TAE was successfully performed with 11 platinum coils in the branch of the renal artery feeding the aneurysm. According to a review of the literature, the incidence of AVF is higher in transplanted kidneys than in native kidneys (7.5% vs. 2.1%) because transplanted kidneys, as single kidneys, are likely to be punctured repeatedly at the same site. When renal biopsy of a transplanted kidney is performed, previous biopsy puncture sites should be considered and the biopsy should be performed at a different site, if possible, to prevent the development of AVF.

Interventional management of renal transplant arteriovenous fistula

Percutaneous needle biopsy has become an indispensable tool for the evaluation and management of patients with renal allograft dysfunction. But this invasive procedure is not without risk. Vascular injury in the form of arteriovenous fistula, pseudoaneurysm, or arteriocalyceal fistula may result in symptoms that require percutaneous endovascular intervention. In this article, the occurrence, detection, and treatment of biopsy-related renal transplant injury are described.