Endovascular management of arteriovenous fistula post-biopsy of pediatric transplanted kidney using embolization with detachable coils

Background Ultrasound guided transplant kidney biopsy is required to exclude rejection or other causes of allograft dysfunction. Arteriovenous fistula (AVF) is a known complication, with occurrence rates from 1.5 to 18%. AVF may heal spontaneously, however persistent lesions may result in hypertension, renal impairment or hematuria. Objective The study purpose was to investigate the technical details and outcomes of post-biopsy kidney transplant AVF in children, treated by interventional radiology. Materials and methods Retrospective review of renal transplant AVF embolization procedures in a pediatric tertiary center. Clinical details, including transplant history, biopsy, AVF diagnosis, embolization procedural details and post-embolization clinical course, were collected. Results Three cases were identified, with a mean age of 15 years. Embolization was indicated due to long-term persistence and increasing lesion size on serial imaging. Ultrasound and CT were used for procedural planning. In all cases, a femoral arterial access approach was used, with a combination of two detachable coils (framing and packing), achieving AVF occlusion. A 100% technical success rate was achieved with occlusion of the lesion, cessation of early venous filling and improved flow to the adjacent renal parenchyma. This has persisted in post-procedure imaging follow-up (over 6 months in all 3 cases, over one year in 2 cases). No minor or major adverse events were observed. Conclusion This study illustrates that embolization with detachable coils is a feasible option to treat post-biopsy kidney transplant AVF in children. A framing and packing coil combination is the preferred approach.