Up to 70 percent of adults with sickle cell anemia will develop chronic kidney disease, many of whom will require dialysis or transplantation. But since the damage often begins in childhood, identifying the early signs of kidney disease could shift that trajectory.
That’s the goal of Jeffery Lebensburger, D.O.’s research at Children’s of Alabama, for which he was recently awarded a prestigious National Institutes of Health R01 grant. Julie Kanter, M.D., who co-directs the Comprehensive Sickle Cell Center at the University of Alabama at Birmingham (UAB), is also involved.
“This project will develop a novel approach to monitoring changes in kidney function over time that is specific for patients with sickle cell anemia,” said Lebensburger, who directs UAB’s hematology section in the Division of Pediatric Hematology. “This will improve our clinical capacity to identify sickle cell anemia patients who are at risk for chronic kidney disease and who may benefit from additional prospective therapies.”
The early signs of kidney disease are usually silent. By the time obvious markers like protein in the urine develop, the loss of kidney function is often too advanced to reverse. “We need to control it in childhood,” Lebensburger said. Particularly since people with sickle cell anemia who go on dialysis are eight times more likely to die from kidney-related complications within seven years than those without the disease.
“Given the high mortality early in life from kidney disease, it is vital that we monitor kidney disease progression in children and adults,” he said. But the standard glomerular filtration rate (GFR) blood test provides, at best, a “guess” of kidney function. The tests also weren’t developed for sickle cell patients, he said. The gold standard, a measured test of how well the kidney eliminates a contrast agent, takes four to six hours and is very expensive.
“For us to appropriately track kidney function in this population and prevent the devastating complications of renal disease in our patients, we need a GFR equation that is validated for those with sickle cell, not for other populations,” Lebensburger said. Which is what his research is designed to do.
“We’re starting from scratch to develop this,” he said, performing normal blood work in 200 children and 200 adults and then developing a new calculation of kidney function that is valid for our sickle cell patients. “Then we’ll know what’s happening and can better track patients’ kidney function and prevent the devastating effects of kidney disease.”