Ultrasound-Guided Percutaneous Renal Biopsy in 295 Children and Adolescents: Role of Ultrasound and Analysis of Complications

INTRODUCTION Percutaneous renal biopsy (PRB) is a decisive diagnostic procedure for children and adolescents with renal diseases. Aim of this study was to evaluate retrospectively the complication rates of percutaneous kidney biopsies and their therapeutic consequences to assess the role of ultrasound-guidance including Doppler ultrasound examinations in preparation, execution and follow-up care and to present a recommended protocol. PATIENTS AND METHODS Institutional review board approved this retrospective study; informed consent was waived. Between 1997 and 2011 a total of 438 ultrasound-guided biopsies were performed in 295 patients, 169 of the biopsies were performed on kidney transplants. Average age of patients was 10.2+/-5.2 years (range of 15 days until age of 23). Before and post biopsy ultrasound examination including Doppler examination was carried out. Biopsy itself was ultrasound monitored. Complications were analysed with regard to age of patient, kidney transplants, year of occurrence, number of punctures, performing physician and time interval of occurrence to develop an optimized protocol for ultrasound-guidance. RESULTS In 99% of cases successful PRB were performed, i.e. enough kidney parenchyma for histological analysis was obtained. No lethal or major complication that required surgical intervention occurred. Eighteen relevant complications were observed (complication rate: 4.1%). Except in one case in which additional MRI diagnostic was necessary, ultrasound examination after 4 hours post biopsy or even earlier when symptoms occurred, was able to detect complications and determine indications for intervention. CONCLUSION Ultrasound-guided PRB is an established and effective method in children and adolescents, but shows a certain rate of complications and therefore should not be indicated without diligence. Ultrasound including Doppler ultrasound is a valuable tool in preparation, guidance of biopsy, detection of complications and in follow-up care. Ultrasound examinations (including Doppler) pre-, during and 4 hours post kidney biopsy and, depending from case, a few days until weeks after biopsy is recommended.