Abstract: SA-PO0078
Urine Complement Activation Factor Ba Predicts Persistent AKI in Critically Ill Adults
Session Information
- AKI: Clinical Diagnostics and Biomarkers
November 08, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 102 AKI: Clinical, Outcomes, and Trials
Authors
- Stenson, Erin K., University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- You, Zhiying, University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Semler, Matthew W, Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Siew, Edward D., Vanderbilt University Medical Center, Nashville, Tennessee, United States
- Thurman, Joshua M., University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
- Kendrick, Jessica B., University of Colorado Anschutz Medical Campus, Aurora, Colorado, United States
Background
Acute kidney injury is common in critically ill adults, lacks treatment options, and associated with high morbidity and mortality. The alternative pathway of complement has been implicated in AKI pathogenesis and complement therapeutics exist. We aimed to determine the association between persistent AKI and urine Ba, an alternative pathway activation fragment.
Methods
We leveraged a prior clinical trial that enrolled critically ill adults. Urine was obtained on day 2, frozen at -80°C, and urine Ba was quantified by ELISA. Primary outcome was persistent AKI, defined as serum creatinine (sCr) ≥1.5x baseline for ≥48 hours. Recovered AKI was defined as sCr <1.5x baseline by 48 hours after AKI diagnosis. Logistic regression were used to determine differences and adjusted for APACHE-2 score (an illness severity estimate). Log value of urine Ba to base 2 was used in analysis. AUC-ROC curves were created.
Results
250 patients were included of which 166 (66%) had no AKI, 52 (21%) had stage 1 AKI, 18 (7%) had stage 2 AKI, and 14 (6%) had stage 3 AKI. Of those with AKI, 40 (48%) had persistent AKI. Urine Ba was significantly higher in patients with stage 3 AKI compared to stage 1 AKI and patients without AKI; p <0.05, Figure. Patients with persistent AKI had higher urine Ba values (median 1354 ng/mL; IQR 312, 4154) compared to patients with AKI recovery (median 208 ng/mL; IQR 51, 1070); p <0.05. On regression analyses, urine Ba was significantly associated with maximum AKI and persistent AKI both on univariate analysis and after adjusting for APACHE score. Urine Ba can be used to predict persistent AKI with an AUC of 0.73 (Figure).
Conclusion
Urine Ba is significantly increased in patients with stage 3 AKI and patients with persistent AKI. Urine Ba may be helpful to delineate between patients with persistent AKI compared to patients with recovered AKI and may guide future clinical trial interventions.
Funding
- NIDDK Support