Balancing Glomerular Adequacy and Bleeding Risk in Native Kidney Biopsy: A Multicenter Cohort Study of Multiple Needle Passes.

RATIONALE &

OBJECTIVE

Whether performing multiple needle passes during adult native kidney biopsy increases clinically significant bleeding is unclear. We evaluated the association between needle-pass number and major bleeding complications and hemoglobin level decline.

STUDY

DESIGN

Multicenter retrospective cohort study.

SETTING &

PARTICIPANTS

Adults undergoing percutaneous native kidney biopsy at 2 high-volume centers in Japan (January 2020 to December 2024) were included (n = 58). Open or lateral decubitus biopsies and cases with undocumented pass counts were excluded.

EXPOSURE: Number of needle passes.

OUTCOMES: Major bleeding (transfusion, bladder irrigation, interventional radiology, surgical hemostasis, or death) and next-day hemoglobin level decline.

ANALYTICAL APPROACH: Major bleeding was evaluated using Firth penalized logistic regression (unadjusted and estimated glomerular filtration rate adjusted). Hemoglobin level decline was evaluated using linear regression with a sensitivity analysis adjusting for baseline hemoglobin.

RESULTS

The median number of needle passes was 5 (interquartile range, 4-6). Glomerular adequacy (≥ 10 glomeruli) was achieved in 94.5%, with a median of 30 glomeruli (interquartile range, 17-52). Major bleeding occurred in 7 patients (1.5%), including transfusion in 3 (0.7%), bladder irrigation in 3 (0.7%), and interventional radiology in 1 (0.2%); no surgical hemostasis or deaths occurred. Needle-pass number was not significantly associated with major bleeding (odds ratio per pass, 1.23; 95% confidence interval [CI], 0.81-1.65; P = 0.29) or after adjustment for estimated glomerular filtration rate (odds ratio per pass, 1.14; 95% CI, 0.77-1.53; P = 0.46). Needle-pass number was not significantly associated with hemoglobin decline (β, -0.028 g/dL per pass; 95% CI, -0.065 to 0.009; P = 0.14), with consistent results in sensitivity analysis.

LIMITATIONS: Major bleeding events were few, limiting precision; the retrospective 2-center design may limit generalizability and introduce bias.

CONCLUSIONS

In this cohort, needle-pass number was not significantly associated with major bleeding or next-day hemoglobin decline. These findings support performing additional passes when needed to obtain adequate tissue while considering baseline bleeding risk.