Initiatives will support VUR, hydronephrosis research

February 1, 2007

Atlanta-A study funded by the National Institutes of Health and a new registry promise to provide needed information on the incidence, prevalence, and consequences of two important urologic conditions in children: vesicoureteral reflux and prenatal hydronephrosis. Both the study and the registry were highlighted at the American Academy of Pediatrics Section on Urology annual meeting here.

Atlanta-A study funded by the National Institutes of Health and a new registry promise to provide needed information on the incidence, prevalence, and consequences of two important urologic conditions in children: vesicoureteral reflux and prenatal hydronephrosis. Both the study and the registry were highlighted at the American Academy of Pediatrics Section on Urology annual meeting here.

Saul Greenfield, MD, director of the division of pediatric urology at Women and Children's Hospital in Buffalo, introduced the NIH-funded Randomized Intervention for Children for Vesicoureteral Reflux (RIVUR) study. This randomized study will evaluate the impact of antimicrobial prophylaxis in improving the symptoms and consequences of VUR. RIVUR investigators will create a database of more than 600 children with VUR and track their outcomes.

"The incidence of scarring in association with urinary tract infection in children who have reflux is low. There have been challenges to the conventional wisdom that continual prophylaxis is needed in all children with VUR," Dr. Greenfield told the AAP audience.

The primary endpoint of the study is number, timing, and recurrence of urinary tract infections. The secondary endpoints are renal scarring, as measured by DMSA scan, and antimicrobial resistance in urinary pathogens.

Other factors that will likely be addressed by RIVUR are compliance with chronic medical therapy, voiding dysfunction, and chronic constipation in children over 3 years of age, antimicrobial resistance in stool cultures, and quality of life. Blood and urine specimens will be kept in a central repository for potential future genetic testing.

Enrollment in RIVUR will begin in 2007. Investigators hope that data from the study and companion genetic investigations will answer a widely debated question in the pediatric urology community: Should all children with VUR be treated with continuous antimicrobial prophylaxis?

Prenatal hydronephrosis registry

Anthony Herndon, MD, assistant professor of the division of urology at the University of Alabama in Birmingham, presented an update of the Society for Fetal Urology Prenatal Hydronephrosis (SFU/Prenatal) registry, which will collect prospective data on patients with prenatal hydronephrosis for 3 years.

Previous studies have shown that prenatal hydronephrosis is associated with higher risk of kidney abnormalities after birth.

"A prospective study is needed to further define these risks," Dr. Hernandon said.

Individual study sites will have complete autonomy over diagnostic and treatment approaches. They will assign a unique identification code to all patients and transmit data to a central server at the University of Alabama. Study site representatives will have password-protected access to the database and can contact a registry manager with any technology-related concerns. Data analysis of individual sites is available for the first 5 years of the study at no cost to the participating institution.

Open enrollment for the pilot phase of the SFU/Prenatal registry began in May 2006. Of the 63 patients currently enrolled, the majority (66%) have been diagnosed with ureteropelvic junction obstruction. Other commonly observed conditions include VUR (11%) and ureterocele (10%).

"The registry will not address a specific hypothesis. It is a vehicle to warehouse data. Specific projects will be hypothesis driven and utilize data points that have been populated in the registry," Dr. Herndon explained.

The architects of the SFU/Prenatal program envision this registry as a tool that will enable researchers to tackle some of the most typical questions in fetal urology, including identification of optimal postnatal treatment approaches for all stages of fetal hydronephrosis and possible refinement of the SFU grading system.

Comprehensive registries are the backbone of large-scale epidemiologic research. They facilitate the determination of incidence, prevalence, and treatment success for a number of disorders.