Vesicoureteral reflux (VUR) means urine flows back from the bladder into the ureter, and sometimes the kidney, instead of in one direction. It is more common in children, and its main risk is repeated kidney infections that can scar the kidney. Many mild cases improve as the child grows.
Medically reviewed by Prof. Dr. Samir Ahmed Al-Samarrai, consultant urologist. Last reviewed:
Causes
- Primary reflux: a congenital weakness of the valve between the ureter and bladder, which can run in families.
- Secondary reflux: high pressure inside the bladder, such as a neurogenic bladder, bladder outlet obstruction or posterior urethral valves in boys.
Grades
| Grade | Description |
|---|---|
| 1 | Reflux into the ureter only |
| 2 | Into the ureter and kidney without widening |
| 3 | Mild to moderate widening |
| 4 | Moderate widening with a tortuous ureter |
| 5 | Severe widening of the ureter and kidney |
Symptoms
- Repeated urinary infections, especially with fever.
- In babies: fever without an obvious cause, vomiting and poor feeding.
- Side or abdominal pain.
- Sometimes found on pregnancy ultrasound as a widened kidney in the baby.
Diagnosis
- Kidney and bladder ultrasound.
- Voiding cystourethrogram to grade the reflux.
- Nuclear kidney scan when needed to look for scars.
- Assessment of voiding and constipation, which affect reflux and infections.
Treatment
It depends on age, grade, how often infections occur and any scarring, according to European paediatric urology guidelines:
- Follow-up and prompt treatment of infections, with treatment of constipation and voiding problems.
- Low-dose preventive antibiotics for some children prone to repeated infections.
- Endoscopic injection at the ureteric opening in selected cases.
- Ureteric reimplantation surgery for severe grades or repeated infections despite treatment.
When to see a doctor urgently
With fever plus urinary symptoms or side pain, especially in babies and children, because early treatment of kidney infection lowers the risk of scarring.
Related
Frequently asked questions
What is vesicoureteral reflux?
Urine flowing back from the bladder into the ureter, and sometimes the kidney, because the natural valve between the ureter and bladder is weak.
What are the grades of reflux?
There are 5 grades: 1 and 2 are mild, 4 and 5 are severe with widening of the ureter and kidney. Mild grades in children often improve as they grow.
Is reflux dangerous?
The risk is repeated kidney infections that can leave scars in the kidney, especially in young children, so infections should be treated promptly and the kidneys followed up.
Can adults have reflux?
Yes, though less often. It may show as repeated kidney infections, or be linked to a neurogenic bladder, bladder outlet obstruction or some operations.
How is reflux diagnosed?
Usually with a voiding cystourethrogram (an X-ray of the bladder during urination with contrast), kidney ultrasound, and sometimes a nuclear kidney scan to look for scars.
Sources
Book a consultation
Prof. Al-Samarrai and Dr. Amer Mousa assess reflux and repeated kidney infections at Prof. Al-Samarrai Medical Center, Dubai Healthcare City, and discuss the options that suit your case. Medical consultations are confidential.
This information is for health education and does not replace a medical examination. See our medical content policy.