Needle guides enhance tissue adequacy and safety of ultrasound-guided renal biopsies

BACKGROUND: Needle guides have recently come into use for ultrasound-guided percutaneous renal biopsies; however, it is not yet clear if the use of needle guides leads to decreased post-biopsy complication rates and improved tissue yields. Thus, we conducted a retrospective single center study comparing biopsy yield, adequacy, and rates of complications before and after utilization of a needle guide device. METHODS: A retrospective analysis was performed on all native kidney biopsies performed before and after June 2015 corresponding to the start of needle guide use. All biopsies in the latter period of the study were performed by a single operator. We compared clinical characteristics, indications, type of investigation, tissue yield, adequacy of procedure, and rates of major and minor complications. RESULTS: A total of 343 biopsies were analyzed, 140 in the pre-needle guide use period (Period I) and 203 in the needle guide use period (Period II). Biopsy yields were similar, irrespective of the use of needle guides. Tissue adequacy was better in Period II (93.7% vs. 84%, P < 0.001, with respect to pathologist-reported inconclusive biopsies. There were no differences in terms of major complications (1.7%) for the two periods; however, the rate of minor complications (8.4%) was significantly reduced in Period II (P = 0.006). According to multiple logistic regression analysis, not using a needle guide (odds ratio, 3.70; P < 0.001) along with low hemoglobin level, higher pre-dialysis serum creatinine level, and high urinary red blood cell count were significant predictors of biopsy complications. CONCLUSION: Use of a needle guide improves biopsy adequacy and is associated with reduced rates of minor complications in native renal biopsies. Therefore, needle guides may be recommended in percutaneous renal biopsies, especially when transitioning to single-operator performed procedures.