ORLANDO – Screening urinalysis should be a part of routine care for children and young adults with hemophilia, although the clinical significance of the finding is still unclear, investigators say.
Among 93 boys and young men with hemophilia A or B followed at a hemophilia treatment center, nearly half were found to have hematuria on routine screening, a possible indicator for future renal problems, said Kyle Davis, MD, and Amy Dunn, MD, from the division of hematology at Nationwide Children’s Hospital in Columbus, Ohio.
Neil Osterweil/Frontline Medical News
Dr. Amy Dunn and Dr. Kyle Davis
“It’s not routine for all centers to screen for hematuria, so there is likely a large number of patients that are underrecognized, who have hematuria but we don’t even know it,” Dr. Davis said in an interview at the World Federation of Hemophilia World Congress.
Hematuria is a recognized complication in patients with hemophilia A and B, second only to joint damage in frequency. In addition, adults with hemophilia have been shown to have a higher prevalence of renal disease than the general population, suggesting that hematuria might be a marker or harbinger of later renal disease, the authors proposed in a scientific poster.
The investigators conducted their study as part of a quality improvement program at their center aimed at increasing the frequency of urine screening in patients with hemophilia during annual comprehensive visits.
They looked at urinalysis results collected from all male patients older than 2 years with hemophilia A or B seen at their center from August 2011 through September 2015. They defined hematuria as the presence of three or more red blood cells on at least one urinalysis sample.
They also performed univariate logistic regression to evaluate the association of hematuria with patient age, race, hemophilia type and severity, treatment regimen, and history of inhibitory antibodies.
A total of 93 patients, 67 with hemophilia A and 26 with hemophilia B, were included. In all, 43 patients (47%) were identified as having hematuria, with a median of seven red cells. Hematuria was seen in 37 patients with hemophilia A (55%), and in 6 patients with hemophilia B (23%).
Characteristics associated with risk for hematuria included older age and hemophilia A.
Imaging studies available on 24 of the 93 patients showed renal calculi in 3 patients, minor pelviectasis in 1, and congenital dysplastic left kidney, ureterocele, and right hydroureter in 1 patient.
Dr. Davis and Dr. Dunn said that while screening urinalysis could be considered as a part of routine hemophilia, additional studies are needed to replicate the finding in other treatment centers and to determine whether urinalysis results can be predictive of future renal disease, and if so, whether interventions might help.
“For example, there is the potential that if you recognize hematuria in a patient and that patient is currently on an on-demand treatment process, should we switch to prophylaxis?” Dr Davis said.
Dr. Dunn noted that “certainly there are high-risk populations who should be screened, like our patients who have an active inhibitor or even a tolerized inhibitor. Our data suggest that we ought to be looking a bit more closely at those patients, and perhaps that will help us tease out the cause of this. Can we blame it all on hemophilia, or is there something else going on?”
The study was internally funded. Dr. Davis and Dr. Dunn reported no relevant disclosures.