2780 THE STRAIGHTFORWARD AND IMMEDIATE KIDNEY BIOPSY USING A GUIDE NEEDLE (SIGN) REDUCES THE PUNCTURE TIME AND ENABLES ADEQUATE TISSUE TO BE OBTAINED

Abstract Background and Aims Advances in kidney biopsy procedures have improved tissue adequacy and reduced complications. Here, we report the usefulness of the Straightforward and Immediate ultrasound-guided kidney biopsy using a Guide Needle (SIGN) technique, which allows the operator to insert a biopsy gun through a guide needle placed into the fascia of the posterior abdominal wall. In this study, we retrospectively analyzed our daily practice to determine whether this technique enables nephrologists, including nephrology fellows, to shorten the procedure time and obtain more glomeruli with complication rates comparable to those of the standard ultrasound-guided kidney biopsy technique. Methods A single-center retrospective cross-sectional study was conducted to compare the time spent on the procedure and the number of glomeruli obtained in a group using the SIGN technique (n = 81) and a group using the standard ultrasound-guided renal biopsy technique with a needle guide (n = 143). Biopsies were performed by four board-certified nephrologists of the Japanese Society of Nephrology and four fellows. It was left to the operator to decide whether to use the standard technique or the SIGN technique. In the standard technique, an operator inserted a biopsy gun through a needle guide attached to the ultrasound probe and obtained a biopsy core from the lower pole of the kidney. In the SIGN technique, after local anesthesia, an operator inserted a 17-gauge guide needle (TSK Laboratory, Tochigi, Japan) through the needle guide without making a skin incision. The guide needle was placed in the fascia of the posterior abdominal wall. Then the operator inserted a biopsy gun through the guide needle into the lower pole of the kidney and obtained the biopsy core. The puncture time was calculated by subtracting the minute of the last puncture from the first. The number of glomeruli in the specimen for light and fluorescence microscopy was counted by kidney pathologists who did not have procedural information. Results The proportion of fellows using the SIGN method was significantly higher than that of specialists (56.9% and 27.7%, respectively, P