Urine normally flows in one direction and in one direction, called the anterograde direction, from the kidneys to the bladder through the ureters. Vesicoureteral reflux is retrograde flow of urine from the bladder into the ureters and kidneys.
The vesicoureteral valve opens in only one direction and is responsible for preventing retrograde flow. More than a valve, it is a valve-like structure, so it is more accurately called the vesicoureteral junction.
The vesicoureteral junction is formed by a short (1-2 cm) portion of the ureters that cross the bladder wall obliquely. When the bladder fills and expands, this part of the ureters is compressed and closed.
Vesicoureteral reflux is estimated to occur to some degree in more than 10% of the population. In babies and in childhood, vesicoureteral reflux is much more common than in adults, mainly because the portion of the ureters that crosses the bladder wall and forms the vesicoureteral valve is shorter, so babies and children are a special attention group.
This increased susceptibility naturally decreases with age. In children younger than 1 year of age, 70% of urinary tract infections are associated with vesicoureteral reflux. The prevalence drops to 15% at 12 years of age.
In childhood it is more common in boys than in girls, but in adulthood it is clearly a condition that affects women much more. Up to 85% of vesicoureteral reflux in adults occurs in women and increases the risk of bladder infections and pyelonephritis.
Vesicoureteral reflux symptoms
Most cases of vesicoureteral reflux occur asymptomatically, especially in children, and remain so until eventually there are infections in the bladder, ureters, or, in more advanced cases, also in the kidneys.
Among the most common symptoms of these infections are fever, tiredness, lethargy and loss of appetite. Painful urination and frequent urination are also common.
most frequent causes
In healthy individuals, the structure at the inlet of the bladder and the muscular attachments of the ureters provide a valve effect that closes the retrograde passage during urine storage and during micturition.
In people with vesicoureteral reflux, there is some failure of this mechanism, resulting in urine returning to the ureters and kidneys.
Vesicoureteral reflux can be studied in two types, primary and secondary:Primary vesicoureteral reflux: It is due to congenital structural changes at the vesicoureteral junction that prevent the valvular effect, such as short submucosal length of the ureters or defects in the longitudinal musculature of the ureter in the portion in contact with the bladder. Secondary vesicoureteral reflux: in this case, the person is born with a normal and functional vesicoureteral junction, but at some point in their life they develop some anatomical problem, for example ureteral stenosis, or functional, for example, infections, neurogenic bladder, etc.
The diagnosis of vesicoureteral reflux is usually made using imaging techniques such as a voiding cystogram or cystourethrogram. The latter is the method of choice whenever possible, as ultrasound and other imaging techniques may appear normal.
Vesicoureteral reflux is graded from 1 to 5 depending on the severity. 85% of grade I and II vesicoureteral reflux cases in children resolve on their own.
GalleryUltrasonography in case of primary vesicoureteral reflux with an abnormal vesicoureteral junction and a distally dilated ureter. Grade IV vesicoureteral reflux
In neonates and infants with vesicoureteral reflux, treatment is the first priority. reduce the risk of infections, which is mainly done with the administration of antibiotics for prophylactic purposes.
It is also important to pay attention to urination control. If urination is infrequent or there is urinary retention, infections are more likely to occur.
In certain cases, the application of a gel to the vesicoureteral junction by endoscopy, usually dextranomer and hyaluronic acid, can be evaluated, which helps in the restoration of valve function.
If medical intervention is unable to prevent the onset of recurrent infections, particularly if the infections reach the kidneys, surgical intervention to try to restore functionality to the vesicoureteral junction is considered.
In grade I-III reflux, surgical intervention is left as a last option, especially in children and infants, as most cases resolve on their own. In grade IV, surgery is avoided, but the rate of surgery is much higher. In grade V, surgery is almost the only solution, especially in adults.