Adequacy and complication rates with 14- vs. 16-gauge automated needles in percutaneous renal biopsy of native kidneys.

In performing percutaneous renal biopsy (PRB) of native kidneys, an increasing use of 16-gauge automated biopsy needles has been observed. We compare the adequacy and safety of PRBs in adults performed with a 14-gauge (n = 82) vs. 16-gauge (n = 55) automated needle using real-time ultrasound (US) from 1/2010 to 12/2013. Baseline clinical and laboratory data along with outcome data (renal US 1-hour postbiopsy, biopsy adequacy, and safety) were collected prospectively. There was no difference in age, gender, blood pressure, serum creatinine, or pre-PRB hemoglobin at baseline for PRBs performed with a 14- vs. 16-gauge needle. The number of glomeruli obtained per biopsy was similar (29 ± 11 vs. 31 ± 14, p = 0.6) and adequate tissue for diagnosis was obtained in 99% and 100% of biopsies. The clinical complication (8.5% vs. 9.1%, p = 1.0), transfusion (7.3% vs. 7.2%, p = 1.0), and embolization (3.7% vs. 1.8%, p = 0.6) rates were not significantly different for 14- vs. 16-gauge needles, but by routine renal US 1-hour post-PRB, a perinephric hematoma was demonstrated more often in biopsies done with the 14-gauge needle (39% vs. 22%, P 0.04). Thus, while the success of PRB of native kidneys is similar for both needle gauges, the potential for complication may be less using a 16-gauge automated needle.