Abstract: FR-PO1169
Albuminuria Sparing Effects of Hydroxyurea in Children with Sickle Cell Anemia
Session Information
- Pediatric Nephrology - I
October 26, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Pediatric Nephrology
- 1600 Pediatric Nephrology
Authors
- Zahr, Rima S., University of Tennessee , Memphis, Tennessee, United States
- Hankins, Jane S., St. Jude Children''s Research Hospital, Memphis, Tennessee, United States
- Wang, Winfred C., St. Jude Children''s Research Hospital, Memphis, Tennessee, United States
- Kang, Guolian, St. Jude Children''s Research Hospital, Memphis, Tennessee, United States
- Li, Chen, St. Jude Children''s Research Hospital, Memphis, Tennessee, United States
- Estepp, Jeremie H., St. Jude Children''s Research Hospital, Memphis, Tennessee, United States
- Lebensburger, Jeffrey, UAB, Mountain Brook, Alabama, United States
Background
Renal complications in sickle cell anemia (SCA) begin early in childhood as hyposthenuria, glomerular hyperfiltration and albuminuria. Hydroxyurea (HU) use in SCA improves anemia, induces fetal hemoglobin and reduces sickle cell complications. We evaluated the long term effects of initiating hydroxyurea in patients with albuminuria and without albuminuria. We tested the hypothesis that initiation of HU in SCD children and young adults with albuminuria would improve urine measurements.
Methods
Participants were children < 18 yrs of age with SCA who were enrolled in two prospective cohorts and had longitudinal assessment of urine albumin to creatinine ratios (ACR) available. ACR values were captured at baseline, during the first 12 months of HU therapy and every year thereafter. The main outcome of the analysis, the development of albuminuria, was evaluated by two methodologies: a comparison of proportion between baseline and on hydroxyurea therapy and a time-to-development of albuminuria during hydroxyurea therapy.
Results
Albuminuria was present at baseline in 49% of our cohort. At one year of HU treatment, 38% with albuminuria normalized. Participants older than 10 at HU initiation had a 1.35x increase in the hazard ratio for developing ACR compared to younger than 10 years. We found that an ACR level of ≥ 100 mg/g to be a significant cut-point for recurrence.
Conclusion
The impact of HU on normalizing albuminuria may be dependent on baseline age at initiation of treatment and level of albuminuria. Our study provides the novel finding that hydroxyurea, initiated in younger age with lower levels of albuminuria can strongly benefit from the addition of HU therapy and titration to the maximal tolerated dose. Clinicians should not defer initiating HU for renoprotection until patients are older and experiencing moderate to severe albuminuria.