Vesicoureteral reflux

Most children with vesicoureteral reflux are asymptomatic. Vesicoureteral reflux may be diagnosed as a result of further evaluation of dilation of the kidney or ureters draining urine from the kidney while in utero as well as when a sibling has VUR (though routine testing in either circumstance is controversial). Reflux also increases risk of acute bladder and kidney infections, so testing for reflux may be performed after a child has one or more infections.

In infants, the signs and symptoms of a urinary tract infection may include only fever and lethargy, with poor appetite and sometimes foul-smelling urine, while older children typically present with discomfort or pain with urination and frequent urination.

In healthy individuals the ureters enter the urinary bladder obliquely and run submucosally for some distance. This, in addition to the ureter's muscular attachments, helps secure and support them posteriorly. Together these features produce a valvelike effect that occludes the ureteric opening during storage and voiding of urine. In people with VUR, failure of this mechanism occurs, with resultant backward (retrograde) flow of urine.

VCUG demonstrating bilateral Grade II (non-dilating) vesicoureteral reflux.

The following procedures may be used to diagnose VUR:

• Cystography
• Fluoroscopic voiding cystourethrogram (VCUG)
• Abdominal ultrasound
• Technetium-99m Dimercaptosuccunic Acid (DMSA) Scintigraphy

An abdominal ultrasound might suggest the presence of VUR if ureteral dilatation is present; however, in many circumstances of VUR of low to moderate, even high severity, the sonogram may be completely normal, thus providing insufficient utility as a single diagnostic test in the evaluation of children suspected of having VUR, such as those presenting with prenatal hydronephrosis or urinary tract infection (UTI).[4]

VCUG is the method of choice for grading and initial workup, while RNC is preferred for subsequent evaluations as there is less exposure to radiation. A high index of suspicion should be attached to any case where a child presents with a urinary tract infection, and anatomical causes should be excluded. A VCUG and abdominal ultrasound should be performed in these cases

DMSA scintigraphy is used for the evaluation of the parenchymal damage, which is seen as cortical scars. After the first febrile UTI, the diagnostic role of an initial scintigraphy for detecting the damage before the VCUG was investigated and it was suggested that VCUG can be omitted in children who has no cortical scars and urinary tract dilatation.[5][6]

Early diagnosis in children is crucial as studies have shown that the children with VUR who present with a UTI and associated acute pyelonephritis are more likely to develop permanent renal cortical scarring than those children without VUR, with an odds ratio of 2.8.[7] Thus VUR not only increases the frequency of UTIs, but also the risk of damage to upper urinary structures and end-stage renal disease.[8]

The goal of treatment is to minimize infections, as it is infections that cause renal scarring and not the vesicoureteral reflux.[9] Minimizing infections is primarily done by prophylactic antibiotics in newborns and infants who are not potty trained. However, in children who are older, physicians and parents should focus on bowel and bladder management. Children who hold their bladder or who are constipated have a greater number of infections than children who void on a regular schedule. When medical management fails to prevent recurrent urinary tract infections, or if the kidneys show progressive renal scarring then surgical interventions may be necessary. Medical management is recommended in children with Grade I-III VUR as most cases will resolve spontaneously. A trial of medical treatment is indicated in patients with Grade IV VUR especially in younger patients or those with unilateral disease. Of the patients with Grade V VUR only infants are trialled on a medical approach before surgery is indicated, in older patients surgery is the only option.

It has been estimated that VUR is present in more than 10% of the population. Younger children are more prone to VUR because of the relative shortness of the submucosal ureters. This susceptibility decreases with age as the length of the ureters increases as the children grow. In children under the age of 1 year with a urinary tract infection, 70% will have VUR. This number decreases to 15% by the age of 12. Although VUR is more common in males antenatally, in later life there is a definite female preponderance with 85% of cases being female.

As early as the time of Graeco-Roman physician and anatomist Galen described the urinary tract and noted that there were specific mechanisms to prevent the reflux of urine.[11]