Abstract: SA-PO1081
Accuracy of Smartphone-Enabled Urinary Albumin-to-Creatinine Ratio (uACR) Testing
Session Information
- CKD: Epidemiology, Risk Factors, and Prevention - 3
October 26, 2024 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: CKD (Non-Dialysis)
- 2301 CKD (Non-Dialysis): Epidemiology, Risk Factors, and Prevention
Authors
- Jeddah, Danielle, Healthy.io, Boston, Massachusetts, United States
- Bevins, Nicholas James, Birdrock Laboratories, San Diego, California, United States
- Ronen, Matan, Healthy.io, Boston, Massachusetts, United States
- Zohar, Ron, Healthy.io, Boston, Massachusetts, United States
- Tangri, Navdeep, University of Manitoba Max Rady College of Medicine, Winnipeg, Manitoba, Canada
Background
Urinary albumin to creatinine ratio (uACR) testing is crucial for diagnosing, staging, and managing chronic kidney disease (CKD), yet testing rates remain short of guideline recommendations. Guidelines recommend semi-quantitative point-of-care testing (POCT) with ≥85% sensitivity when lab access is limited or when POCT offers advantages like convenience, immediate results, and elimination of sample transportation. We evaluated the accuracy of the Minuteful-Kidney Test (MKT), an FDA-cleared, smartphone-enabled, semi-quantitative test of uACR for home use, improving accessibility to kidney health assessment
Methods
We conducted a diagnostic study comparing the Minuteful-Kidney Test to the Beckman Coulter AU 480 Analyzer, a gold standard laboratory method, in a population at risk for kidney disease. From January to March 2024, we analyzed 615 urine samples in an accredited U.S. laboratory. Inclusion criteria were medical conditions or risk factors for kidney damage based on EMR data. Exclusion criteria were extreme urine pH, diluted samples, and samples with preservatives. Sensitivity, specificity, PPV, and NPV were calculated
Results
Among 615 samples, 60 met exclusion criteria, leaving 555 for analysis. The Minuteful-Kidney Test showed a sensitivity of 96.2% (95% CI 94.2%-98.2%) and specificity of 84.2% (95% CI 80.7%-87.7%), with an NPV of 98.6% (95% CI 97.4%-99.8%) and PPV of 66.8% (95% CI 60.3%-73.3%). Albuminuria was identified in 24.9% (95% CI 21.3-28.5) of the samples based on the quantitative device. The test accurately classified 85.6% of samples into KDIGO albuminuria categories, identifying all 25 (100%) laboratory-confirmed A3 samples as abnormal
Conclusion
The Minuteful-Kidney Test demonstrated high sensitivity (96.2%), exceeding the guideline-required 85%, and robust specificity for detecting albuminuria in high-risk CKD populations. The device can streamline CKD screening and enable early intervention, for patients with or at risk for CKD.
Comparative Analysis of Minuteful - Kidney Test and Quantitative Analyzer for Albuminuria Detection
| Beckman Coulter AU 480 Analyzer | |||||
| Normoalbuminuria | Albuminuria | Total | |||
| Minuteful - Kidney Test | (A1) uACR ≤30 mg/g | (A2) uACR 30-300 mg/g | (A3) uACR ≥300 mg/g | ||
| (A1) uACR ≤30 mg/g | 351 | 5 | 356 | NPV 98.6% | |
| (A2) uACR 30-300 mg/g | 65 | 102 | 3 | 170 | PPV 66.8% |
| (A3) uACR ≥300 mg/g | 1 | 6 | 22 | 29 | |
| Grand Total (n) | 417 | 113 | 25 | 555 | |
| Positivity Rate 24.9% | Specificity 84.2% | Sensitivity 96.2% | |||
Funding
- Private Foundation Support