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Updated: Jun 3, 2026
05:23
Continuous Manual Exchange Transfusion for Patients with Sickle Cell Disease: An Efficient Method to Avoid Iron Overload
Published on: March 14, 2017
Renin-angiotensin-aldosterone system inhibition exacerbates anemia in sickle cell disease
Najmeh Eskandari1, Emma Pappano1, Maria Armila D Ruiz1
1Comprehensive Sickle Cell Center, Division of Hematology and Oncology, Department of Medicine, University of Illinois Chicago, Chicago, IL.
Blood
|June 1, 2026
Summary
Renin-angiotensin-aldosterone system inhibitors (RAASi) may lower hemoglobin in sickle cell disease (SCD) patients. Monitoring hemoglobin is crucial when using RAASi in this population.
Area of Science:
- Hematology
- Nephrology
- Pharmacology
Background:
- Renin-angiotensin-aldosterone system inhibitors (RAASi) are used for albuminuria in sickle cell disease (SCD).
- RAASi can worsen anemia in general and diabetic populations via unknown mechanisms.
- The effect of RAASi on anemia in chronic hemolytic disorders like SCD is not well understood.
Purpose of the Study:
- To investigate the impact of RAASi on hemoglobin levels in patients with SCD.
- To explore the mechanisms by which RAASi might affect erythropoiesis in SCD.
Main Methods:
- Cross-sectional analysis of 658 Walk-PHaSST participants.
- Longitudinal analysis of two cohorts (n=24 and n=32) receiving RAASi therapy.
- Studies in SCD mice treated with losartan, assessing hemoglobin, reticulocyte counts, bone marrow progenitor cells, and histopathology.
Main Results:
- RAASi use was linked to lower hemoglobin in SCD patients (β -0.46±0.21; P=0.032).
- RAASi therapy reduced hemoglobin by -0.44±0.14g/dL (P=0.006) and -0.53±0.17g/dL (P=0.005) in longitudinal cohorts.
- Losartan-treated SCD mice showed reduced hemoglobin, reticulocyte counts, and erythroid progenitor formation, with lower erythroid/myeloid ratios in bone marrow.
Conclusions:
- RAASi therapy is associated with decreased hemoglobin levels in patients with SCD.
- The findings suggest RAASi may impair erythropoiesis in SCD, potentially through effects on bone marrow progenitors.
- Close monitoring of hemoglobin is recommended for SCD patients using RAASi.
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