Abstract: TH-PO1038
Potential Value of Near Real-Time Transdermal GFR Measurement: Estimated GFR Results by CKD-EPI Serum Creatinine Misclassifies CKD Stage in One of Three Adults
Session Information
- CKD Progression and Complications: Diagnosis, Prognosis, Risk Factors
November 02, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: CKD (Non-Dialysis)
- 2302 CKD (Non-Dialysis): Clinical, Outcomes, and Trials
Authors
- Goldstein, Stuart, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
- Dorshow, Richard B., MediBeacon, St.Louis, Missouri, United States
Background
Currently, chronic kidney disease is most often staged using the serum creatinine-based CKD-EPI equation to estimate GFR (eGFR). Serum creatinine is confounded by several well-known factors including chronic inflammation, muscle mass, medications, tubular SCr secretion and hydration status. Available measured GFR methods are challenged by need for multiple blood draws, radiological equipment and time or prolonged urine collections which are unreliable. We have previously shown our plasma GFR assessment (nGFR) with novel fluorescent tracer agent, relmapirazin (also known as MB-102 in the literature), demonstrates outstanding correlation with iohexol measured GFR in Phase I and II studies (n=120 patients, r2=0.99). We have also previously shown transdermal MB-102 GFR assessment (tGFR) shows outstanding correlation with MB102 nGFR (r2=0.95), and can report GFR within 90-120 minutes at the bedside. We assessed the agreement between nGFR and eGFR in the 120 Phase I and II subjects.
Methods
This prospective study evaluated nGFR with the MediBeacon Inc system in 120 adult patients with CKD Stages 1-4. MB-102 distributes in body tissues over 90-120 minutes and starts to be cleared solely by glomerular filtration. We compared the CKD Stage by CKD-EPI and nGFR using plasma measurements MB-102 over 8-12 hours.
Results
Data from all 120 subjects (64 female, median age 55.5 years, median BMI 29 kg/m2) were available for analysis. Reported patient race was White (69), Black (48), American Indian/Alaskan Native (2), Asian (1) and all 6 of the Fitzpatrick Skin Scales were represented.
Figure 1 shows that nGFR and CKD-EPI eGFR differed by at leas one CKD Stage in 32% and at least CKD Stages 4% of the time. Over- and underestimation of CKD was evenly divided.
Conclusion
CKD-EPI eGFR misclassifies true GFR based CKD stage in more than 1/3 of patients. We have completed a Phase II study comparing nGFR to tGFR to demonstrate accurate near real-time GFR assessment at the bedside.