Larger Labs Report Kidney Function Routinely
Labs that conduct the highest number of routine blood tests are more likely than others to report estimated glomerular filtration rate (eGFR), an important measure of kidney function that can identify early kidney disease, according to a survey funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health (NIH). The work is reported in the October issue of the American Journal of Kidney Diseases.
"We are encouraged to find that many labs are routinely reporting eGFR, allowing earlier diagnosis and treatment of kidney disease, " said NIH Director Elias A. Zerhouni, M.D. "But the survey illustrates the need to continue NIH efforts to promote automatic reporting of eGFR by all labs so that more people can benefit from earlier diagnosis."
The survey found that more than 86 percent of the highest-volume independent labs (those in the top 5 percent) and more than 55 percent of all labs in the top quarter of high-volume labs report eGFR, in contrast to only 24 percent of low-volume labs (those in the bottom quarter). The survey demonstrates room for improvement in making eGFR readily available to primary care providers who could be treating early chronic kidney disease — primarily caused by diabetes and high blood pressure — and possibly reducing their patients’ risk for kidney failure, which results in the need for dialysis or a kidney transplant.
"Estimated GFR is an important measure of kidney function that can be easily calculated using serum creatinine and a patient’s age, gender, and ethnicity," said Andrew Narva, M.D., director of NIDDK’s National Kidney Disease Education Program (NKDEP). " It’s a good sign that the highest-volume labs are commonly reporting eGFR. We hope that lower-volume labs will follow their lead as increased reporting may result in earlier identification and treatment of chronic kidney disease." Serum creatinine is a waste product in the blood created by the normal breakdown of muscle cells during activity.
While eGFR reporting is high among high-volume labs, reporting is relatively low overall (38 percent), particularly by labs in physicians’ offices (26 percent) and low-volume independent labs (39 percent). On the positive side, the survey found that about 67 percent of labs that report eGFR do so routinely — without providers needing to ask for the result.
The survey also found that nearly 40 percent of labs are reporting eGFR values above the cutoff of 60 milliliters per minute per 1.73m2 (an estimate of body surface area used to calculate eGFR levels). "NKDEP’s recommendation is to report such values as ‘greater than or equal to 60’ because the equation used to estimate GFR is less reliable and the creatinine result becomes more variable at lower concentrations," explained Greg Miller, Ph.D., chair of the NKDEP’s Laboratory Working Group and author of an editorial in the same issue of the American Journal of Kidney Diseases.