New Markers for Kidney Disease

Abstract

There is ominous growth in chronic kidney disease among the US population, primarily related to type 2 diabetes (1). The current number of patients on dialysis (∼300 000) is growing steadily as the prevalence of end-stage kidney disease grows geometrically with a doubling time of 10 years. The epidemic growth in diabetes, the leading cause of chronic kidney disease, portends continuation of this trend (2). Most patients with end-stage kidney disease will end up on dialysis because the supply of kidneys for transplants is limited to ∼13 000 per year. A further warning sign from the National Health and Nutrition Examination survey is that an estimated 8 million Americans have a ≥50% reduction of their glomerular filtration rate (GFR) (3). This group with impaired kidney function is at risk for progression to end-stage kidney disease as well as for development of cardiovascular disease. One source of hope for stemming the dire trends in kidney disease is progress in the treatment of impaired kidney function, if it is detected and treated early (1)(2). A recent initiative, termed the National Kidney Disease Education Program, seeks to increase public awareness for preventive therapy. Increased awareness will create new demands on laboratories for early and more sensitive detection of kidney disease and for identification of new laboratory markers, such as one evaluated in this issue of the Journal (4). With the recent development of new genomic and proteomic approaches, there is also the potential for identification of many new markers requiring evaluation. The laboratory marker that has long served as the mainstay for detecting impaired kidney function is serum creatinine. Unfortunately, serum creatinine is an insensitive marker of kidney injury. Two factors underlie this insensitivity. …