Urine flows from each kidney through tubes called ureters and into the bladder. When the bladder is full, it squeezes and sends the urine out through the urethra. None of the urine should flow back into the ureter when the bladder is squeezing. Each ureter has a one-way valve where it enters the bladder that prevents urine from flowing back up the ureter.
But in some people, urine flows back up to the kidney. This is called vesicoureteral reflux.
Over time, the kidneys may be damaged or scarred by this reflux. This is called reflux nephropathy
Reflux can occur in people whose ureters do not attach properly to the bladder or whose valves do not work well. Children may be born with this problem or may have other birth defects of the urinary system that cause reflux nephropathy.
Reflux nephropathy can occur with other conditions that lead to a blockage of urine flow, including:
Reflux nephropathy is often found when a child is checked for repeated bladder infections. If vesicoureteral reflux is discovered, the child's siblings may also be checked, because reflux can run in families.
The blood pressure may be high, and there may be signs and symptoms of chronic kidney disease.
Blood and urine tests will be done, and may include:
Vesicoureteral reflux is separated into five different grades. Simple or mild reflux often falls into grade I or II. The severity of the reflux and amount of damage to the kidney help determine treatment.
Simple, uncomplicated vesicoureteral reflux (called primary reflux) can be treated with:
Antibiotics taken every day to prevent urinary tract infections
Controlling blood pressure is the most important way to slow kidney damage. The health care provider may prescribe medicines to control high blood pressure. Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are often used.
Surgery is usually only used in children who have not responded to medical therapy.
More severe vesicoureteral reflux may need surgery, especially in children who do not respond to medical therapy. Surgery to place the ureter back into the bladder (ureteral reimplantation) can stop reflux nephropathy in some cases.
More severe reflux may need reconstructive surgery. This type of surgery may reduce the number and severity of urinary tract infections.
If needed, patients will be treated for chronic kidney disease.
The outcome varies, depending on the severity of the reflux. Some people with reflux nephropathy will not lose kidney function over time, even though their kidneys are damaged. However, kidney damage may be permanent. If only one kidney is involved, the other kidney should keep working normally.
Reflux nephropathy may cause kidney failure in both children and adults.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Herbert Y Lin, MD, PhD, Nephrologist, Massachusetts General Hospital; Associate Professor of Medicine, Harvard Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.