Antibiotics are overused. In recent years, we have become increasingly cautious about their misuse. When parents hear that long-term, daily antibiotics might be recommended for their children with reflux just to prevent urinary tract infections, they are often concerned. But protecting the kidneys can be an excellent reason to take antibiotics.
Urine is normally created by the kidneys, flows down through tubes called ureters, and enters the bladder. The bladder is a holding tank. When the bladder muscle contacts and the sphincter relaxes, urine flows down and out of the body through the urethra.
Why doesn’t the urine flow back into the ureters when the bladder contracts? The ureters enter the thick-walled bladder at an angle. The long path through the muscle acts as a valve. The ureters close as the bladder contracts — an elegant system.
Reflux happens when the muscle-valve doesn’t work. The path of the ureters through the muscle may be too straight or too short, or the muscle in that area may be too thin or too weak. Sometimes the person has an extra ureter with poor valve function. When the bladder contracts, some of the urine is propelled down and out, but some is ejected back up into the ureters.
This puts pressure on the kidneys, and provides an opening for bacteria to travel further up into the body.
Reflux affects about 1 child in 100. It tends to run in families. Children with reflux are usually born with it. If one child has it, about 1/3 of the siblings will have it. If a woman has reflux, about half of her children will.
Reflux is more common in people with other urinary tract problems and in some other conditions, such as spina bifida.
Reflux usually comes to medical attention because someone looked for it after a urinary tract infection.
Apart from infections, the damage done by reflux is often silent and unobserved. Reflux can lead to scarring of the kidneys, high blood pressure, poor growth, and kidney failure.
Reflux is not contagious.
How long it is expected to last depends on the severity of the reflux. Reflux is classified on a scale of Grade I to Grade V. In Grade I reflux, the urine flows up a short way through a normal-appearing, undilated ureter. In Grade II, the urine makes it all the way to the kidney, but the structures still look normal. By Grade V reflux, though, the ureters are dilated like elongated water balloons all the way up the kidney, where the normal structures are compressed and pushed out of place.
Grade I and Grade II reflux will likely go away on their own. Grade III reflux is more likely to resolve the younger the child is when it is diagnosed. Grade IV reflux may also go away, especially if it is only on one side. Grade V reflux rarely disappears without surgery.
If reflux does heal on its own, the average age is 6 or 7.
Imaging studies are needed to diagnose reflux. These are often wise to obtain in young children who have had urinary tract infections. Most will need a renal ultrasound and some will also need a cystogram called a VCUG (a study where a catheter is put into the bladder, some marker is put into the urine, and pictures are taken when the bladder contracts).
The ultrasound is easy, and shows if there is damage to the kidney. When there is a normal ultrasound, parents often wonder why a VCUG or other cystogram is needed. The ultrasound detects kidney scarring (which the VCUG cannot), but it does not detect most reflux.
The most significant lasting damage from reflux comes when infections scar the kidneys. The goal of treatment is to prevent infections and prevent scarring.
Sometimes surgery is done to correct the reflux. Sometimes children are treated with long-term antibiotics to prevent infections while waiting for them to outgrow the reflux.
Children are born with reflux. Preventing the complications of reflux involves either long-term antibiotics to prevent urinary tract infections or surgery to correct the reflux.