Kidney Week

Abstract: SA-PO1140

Validation of a Risk Calculator for Predicting Major Bleeding Complications from Percutaneous Kidney Biopsy

Session Information

• CKD: Patient-Oriented Care and Case Reports
  October 26, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: CKD (Non-Dialysis)

• 2302 CKD (Non-Dialysis): Clinical, Outcomes, and Trials

Authors

• Thorne, Jordan, Nova Scotia Health Authority, Halifax, Nova Scotia, Canada

Jordan Thorne, MD

• More, Keigan, Nova Scotia Health Authority, Halifax, Nova Scotia, Canada

Keigan More, MD

• Vinson, Amanda Jean, Nova Scotia Health Authority, Halifax, Nova Scotia, Canada

Amanda Jean Vinson, MD, MS

• Clark, David, Nova Scotia Health Authority, Halifax, Nova Scotia, Canada

David Clark, MD, MSc

• Tennankore, Karthik K., Nova Scotia Health Authority, Halifax, Nova Scotia, Canada

Karthik K. Tennankore, MD, MS

Group or Team Name

• Kidney Research Institute Nova Scotia.

Background

Percutaneous kidney biopsy (PKB) is valuable for the diagnosis of kidney disease but may be associated with adverse events including major bleeding (the most concerning complication of PKB). A prior study developed a risk calculator for the prediction of major bleeding following PKB, however this calculator has not been externally validated.

Methods

We analyzed all adults that received diagnostic PKB at a large, tertiary care center from 2012-2019. Predictors of major bleeding (defined as the need for blood transfusion, surgical intervention/embolization following PKB or death) included age, body mass index (BMI), platelets, hemoglobin, kidney length and transplant versus native kidney biopsy (the same factors included in the “Risk of bleeding complications after kidney biopsy” calculator; https://perioperativerisk.com/kbrc). Similar to the derivation study, continuous variables were converted to cubic splines and the risk of major bleeding complications were analyzed using logistic regression. Discrimination was assessed using the concordance statistic and calibration was analyzed using the Hosmer-Lemeshow test.

Results

Of 714 patients, 568 with complete data for each predictor were included. 82% of biopsies were from native kidneys. Mean age was 56±16 years, mean BMI was 29.3±6.9 and mean kidney length was 11.3±1.5 cm. Mean platelet and hemoglobin count was 248X10⁹/L and 109 g/L, respectively. A model incorporating these variables demonstrated excellent discrimination (area under the curve 0.858, figure 1a) and good calibration (P=0.9170, figure 1b).

Conclusion

In this external validation study, a risk calculator for patients receiving diagnostic PKB demonstrated excellent calibration and discrimination emphasizing its utility in predicting the risk of major bleeding following PKB.

Figure 1: External validation of “Risk of bleeding complications after kidney biopsy calculator” – receiver operating characteristic curve (1A) and calibration plot (1B)