Sosa-Barrios RH, et al. - The incidence and natural history of arteriovenous fistulae (AVF) post percutaneous renal biopsy (PRB) was elucidated in this study representing the largest single-center experience on routine Doppler ultrasound (US) assessment post PRB. Researchers found that AVF’s were a common complication post PRB that could be easily missed and this finding was contrary to historical data published. Notably, routine US Doppler mapping was discovered to be a cost-effective, non-invasive tool to diagnose and follow up AVF’s, when performed by trained staff.

Methods

• A total of 327 consecutive adult PRB performed at Ramon Cajal University Hospital between January 2011 and December 2014 were retrospectively analyzed.
• A trained nephrologist performed all biopsies under real-time US guidance.
• Regardless of symptoms, routine Doppler mapping and kidney US was done within 24 h post biopsy.
• At the time of biopsy, comorbidities, full blood count, clotting, bleeding time and blood pressure were recorded.
• Post biopsy protocol included vitals and urine void checked visually for haematuria.
• In addition, using logistic regression, links between AVF, needle size were investigated, correcting for potential confounding variables.

Results

• As per the data, 46,5% were kidney transplants and 53,5% were native biopsies.
• Findings revealed that diagnostic material was obtained in 90,5% (142 grafts and 154 native).
• Researchers found that routine kidney Doppler mapping detected 47 AVF’s (14.37%), 95% asymptomatic (n = 45), 28 in grafts (18.4%) and 17 natives (9.7%) (p-value 0.7).
• In terms of comorbidities, passes, cylinders or biopsy yield (p-value NS), both groups were found to be comparable.
• Results revealed that 80% were <1 cm in size and 46.6% closed spontaneously in less than 30 days (range 3–151).
• In addition, it was noted that larger AVF’s (1–2 cm) took a mean of 52 days to closure (range 13–151).
• For AVF (p-value 0.71), needle size was not identified as a statistically significant factor.