The use of algorithms that alter patient medical care based on race has fallen under increasing criticism, as race-based medicine has been shown to contribute to healthcare disparities. In response, the National Kidney Foundation (NKF) and American Society of Nephrology (ASN) formed the “Task Force on Reassessing the Inclusion of Race in Diagnosing Kidney Diseases”. One of the primary recommendations of the final report (September 2021) was to “facilitate increased, routine, and timely use of cystatin C”, as eGFR based on cystatin C alone has never relied on a race parameter to estimate GFR.
Given recommendations by ASN-NKF Task Force to increase use of cystatin C, two key perspectives are discussed:
- the current state of cystatin C assay performance and standardization, as well as the barriers and potential strategies to aid in more widespread implementation of cystatin C testing in clinical laboratories.
- the clinical evaluation of cystatin C results under the new recommendations, and differences in eGFR values compared to the former guidelines using serum creatinine values.
- Understand the importance of accurate GFR estimates in evaluating patient kidney function
- Describe the origins and consequences of race-based estimated glomerular filtration (eGFR)
- Discuss cystatin C’s role in NKF-ASN task force guidelines recommending race-free GFR estimation
- Identify strategies to expand implementation of cystatin C testing in clinical labs
Dr. Amy Karger, MD/PhD
Associate Professor, Dept. of Lab Medicine & Pathology
University of Minnesota
Dr. Amy Karger is an Associate Professor in the Department of Laboratory Medicine and Pathology at the University of Minnesota. She received her MD and PhD degrees from the Mayo Clinic, and completed her residency and fellowship training in clinical pathology and clinical chemistry at the University of Minnesota. Dr. Karger has served as the director of the Central Laboratory for the CKD-EPI research group since 2015, and therefore has expertise on the measurement of filtration markers, including creatinine, cystatin C, beta-2 microglobulin, and beta-trace protein. Dr. Karger is a recognized leader in the field of laboratory medicine, currently serving in leadership roles with both the College of American Pathologists and the American Association of Clinical Chemistry and is a Vice President and Chair of the Credentials Committee for the American Board of Clinical Chemistry. Dr. Karger has extensive experience directing or co-directing central laboratory testing for large clinical trials and multi-institutional research studies, including the Preventing Early Renal Loss in Diabetes (PERL) study and the Epidemiology of Diabetes Interventions and Complications (EDIC) study.
Dr. O. Alison Potok, MD
Assistant Professor, Clinical Medicine in the Division of Nephrology-Hypertension
University of California, San Diego
Dr. Potok is an Assistant Professor of Clinical Medicine in the Division of Nephrology-Hypertension at the University of California, San Diego. She is currently funded by an NIH career development K23 award. For her training, she pursued her medical education at the Université Paris V and completed a residency in internal medicine at the University of Pennsylvania Health System. Dr. Potok was awarded the prestigious American Kidney Fund Clinical Scientist in Nephrology research grant in 2019-2021. She completed her nephrology fellowship at University of California San Diego. Her research focuses on understanding the reasons why serum creatinine and cystatin C may provide different estimates of kidney function within the same individual. She is also interested in tools used to predict the progression of chronic kidney disease.