Dr Sandeep S Motiwale.
Pediatric Surgeon and Pediatric Urologist & P D Hinduja National Hospital & B J Wadia Hospital for Children, Mumbai, India. | Background :
Vesicoureteral reflux (VUR) or the retrograde flow of urine from the bladder into the ureter is an anatomic and functional disorder with potentially serious consequences.
The objectives in the current treatment of VUR are 2-fold. The first goal is the prevention of episodes of acute pyelonephritis with its associated morbidity and mortality. The second goal is to prevent the scarring of the kidney associated with VUR (reflux nephropathy), which increases the risk of hypertension and renal failure in children and adults with VUR. Advances in medical and surgical management of children with VUR now are resulting in measurable decreases in the incidence of reflux nephropathy and its sequelae: hypertension, renal insufficiency, and end-stage renal disease.
Clinical Features :
Most children with VUR present in 1 of 2 distinct groups.
- The first group presents with hydronephrosis, often identified antenatally by ultrasound. These children typically progress through evaluation and treatment in the absence of clinical illness.
- The second group presents with clinical UTI.
- Children often present with nonspecific signs and symptoms. Infection in infants can manifest as failure to thrive, with or without fever. Other features include vomiting, diarrhea, anorexia, and lethargy.
- Older children may complain of voiding symptoms or abdominal pain.
- Pyelonephritis in young children is more likely to present with vague abdominal discomfort rather than with the classic flank pain and tenderness observed in adults. The presence of fever, while highly suggestive of pyelonephritis, is not reliable enough to lead to the diagnosis.
- Even today, children occasionally present with advanced reflux nephropathy, manifesting as headaches or congestive heart failure from untreated hypertension, or with uremic symptoms from renal failure.
Lab Studies
- Diagnosis of UTI is dependent on obtaining accurate urine cultures.
- Growth of more than 100,000 colony-forming units (CFU)/mL is a significant finding on a midstream-voided specimen.
- Urethral catheterization provides substantially better specificity; more than 1000 CFU/mL is considered significant for these samples.
- Although the WBC count, serum levels of C-reactive protein, and other blood tests often are used to assist with the diagnosis, no laboratory tests can reliably distinguish cystitis from pyelonephritis.
- Other laboratory testing should include serum chemistries to assess for baseline renal function.
- CBC can assist in tracking the response to treatment.
Imaging Studies :
Imaging is the basis of diagnosis and management of VUR. The standard imaging tests are the renal and bladder ultrasound and the voiding cystourethrogram (VCUG). Imaging after a first UTI is indicated in all children younger than 5 years with UTI, children of any age with febrile UTI, and boys of any age with UTI. In addition, children with antenatally identified hydronephrosis should be evaluated postnatally.
- The primary purpose of the renal ultrasound is to assess the kidneys for size, parenchymal thickness, and collecting system dilation.
- It largely has replaced the intravenous urogram as the screening test of choice for the upper urinary tract due to the absence of radiation, elimination of contrast reaction risk, and non-invasive technique.
- Despite these advantages, a normal ultrasound study does not exclude VUR. Only the VCUG or nuclear cystogram can reliably exclude VUR.
- The primary radiopharmaceutical used with renal scintigraphy in the setting of pyelonephritis and VUR is technetium TC 99m-labeled dimercaptosuccinic acid (DMSA).
- This agent is taken up rapidly by proximal renal tubular cells and is an excellent indicator of functioning renal parenchyma. Areas of acute inflammation or scar do not take up the radiopharmaceutical and are revealed as cold spots on imaging.
Urodynamic studies reveal functional abnormalities of the lower urinary tract.
- Such testing is most important in patients in whom secondary reflux is suspected, such as patients with spina bifida or boys whose VCUG is suggestive of residual posterior urethral valves.
- Since antireflux surgery is much less successful in patients with secondary reflux, identifying such patients before proceeding with operative intervention is critical.
Medical Care: The treatment of children with reflux aims to prevent kidney infection, kidney damage, and the complications of kidney damage.
Principles of management in children with known VUR :
- spontaneous resolution of VUR is common in young children but is less common as puberty approaches,
- severe reflux is unlikely to resolve spontaneously,
- ster1ile reflux, in general, does not result in reflux nephropathy,
- long-term antibiotic prophylaxis in children is safe, and
- surgery to correct VUR is highly successful in experienced hands.
The mainstay of medical management of reflux is antibiotic prophylaxis. Virtually all children with a new diagnosis of grade I-IV reflux, and some with grade V, are given a trial of medical management. This consists of antibiotics dosed at one fourth of the therapeutic dosage and regular follow-up care and imaging. A typical routine includes renal ultrasound and VCUG or nuclear cystogram every 12-18 months. Since a substantial number of children experience spontaneous resolution of VUR (50-85% of cases with grade I-III VUR), medical management spares this group the morbidity of surgery while protecting the kidneys from further damage.
Surgical Care: Generally accepted indications for surgical treatment include the following :
- breakthrough febrile UTIs despite adequate antibiotic prophylaxis,
- severe reflux (grade V or bilateral grade IV) that is unlikely to resolve spontaneously, especially if renal scarring is present,
- mild or moderate reflux in females that persists as the patient approaches puberty, despite several years of observation,
- poor compliance with medications or surveillance programs, and
- poor renal growth or function or appearance of new scars.
Virtually, all operations designed to treat VUR involve reconstruction of the Uretero-Vesical Junction to create a lengthened submucosal tunnel for the ureter, which functions as a one-way valve as the bladder fills. Dozens of procedures have been described. Surgery for VUR should be performed by a qualified pediatric urologist, experienced in multiple techniques, allowing tailoring of the surgery to the unique circumstances of the individual patient.
Good communication between the Pediatric Urologist and primary care physician is essential for the effective management of VUR. This is especially true for children being managed medically, in whom regular follow-up care and prompt evaluation and treatment of breakthrough UTI are critical in preventing renal damage.
Diet: Children with frequent UTIs often have concurrent problems with constipation and poor bowel habits. Institution of a bowel program in these children can reduce the incidence of infection. High-fiber diets combined with a stool softener, can improve bowel function and reduce colonic and rectal dilation.
Activity: Children with VUR can engage in normal activity. Toilet hygiene, especially proper wiping technique in girls, should be taught to children of appropriate age to reduce incidence of UTI.
Special Concerns :
- Pregnancy and VUR
- The impact of VUR on pregnancy is controversial, but most data suggest that women with childhood VUR have an increased risk of complications during pregnancy.
- A number of studies show that women with VUR are more likely to have pyelonephritis, and women with renal scarring due to childhood VUR have higher rates of hypertension, preeclampsia, obstetric intervention, and miscarriage. Based on these data, surgical repair is recommended in girls with VUR that persists as puberty approaches.
| | | | Compliance with Ethical Standards | | Funding None | | | | Conflict of Interest None | | |
| Cite this article as: | | Motiwale S S. VESICOURETERAL REFLUX. Pediatr Oncall J. 2005;2. |
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