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Continuous Manual Exchange Transfusion for Patients with Sickle Cell Disease: An Efficient Method to Avoid Iron Overload
Published on: March 14, 2017
Annual stroke incidence in Nigerian children with sickle cell disease and elevated TCD velocities treated with
IkeOluwa Lagunju1,2, B J Brown1,2, A O Oyinlade1,2
1Department of Paediatrics, College of Medicine, University of Ibadan, Ibadan, Nigeria.
Insights
Hydroxyurea (HU) significantly lowers transcranial Doppler (TCD) velocities in Nigerian children with sickle cell disease (SCD). This treatment also reduces the incidence of primary stroke, offering a promising alternative for stroke prevention.
Area of Science:
- Pediatric Neurology
- Hematology
- Vascular Medicine
Background:
- Elevated transcranial Doppler (TCD) velocities are key predictors of stroke risk in children with sickle cell disease (SCD).
- Blood transfusions, the standard for stroke prevention, present significant challenges in African healthcare settings.
- Hydroxyurea (HU) has demonstrated efficacy in reducing elevated TCD velocities in pediatric SCD patients.
Purpose of the Study:
- To evaluate the effectiveness of Hydroxyurea (HU) in mitigating primary stroke risk among Nigerian children with SCD and elevated TCD velocities.
- To assess the impact of HU treatment on TCD velocity reduction and stroke incidence in this cohort.
Main Methods:
- Prospective follow-up of 104 children with SCD and TCD velocities ≥170 cm/sec treated with HU.
- Regular 3-monthly TCD and neurological assessments for a minimum of 12 months.
- Monitoring for primary stroke events to determine incidence rates.
Main Results:
- Mean TCD velocities decreased significantly from 198.2 cm/sec to 169.3 cm/sec (P < 0.001) after HU treatment.
- A low stroke incidence of 0.27 per 100 person-years was observed in the study cohort.
- Initial TCD velocities indicated conditional and abnormal risk in 57.7% and 42.3% of children, respectively.
Conclusions:
- Hydroxyurea (HU) effectively reduces TCD velocities and lowers the risk of primary stroke in Nigerian children with SCD.
- HU presents a viable alternative for primary stroke prevention in low- and middle-income countries disproportionately affected by SCD.
- The findings support the expanded use of HU in SCD management to prevent cerebrovascular complications.
Background:
Elevated transcranial Doppler (TCD) velocities accurately predict stroke risk in children with sickle cell disease (SCD). Chronic blood transfusion, the gold standard for primary stroke prevention, is faced with numerous challenges in Africa. Hydroxyurea (HU) has been shown to reduce elevated TCD velocities in children with SCD.
Aim:
To determine the effectiveness of HU in reducing the risk of primary stroke in a cohort of Nigerian children with SCD and elevated velocities treated with HU.
Methods:
Children with SCD and TCD velocities ≥170 cm/sec treated with HU were prospectively followed with 3-monthly TCD and neurological evaluations for ≥12 months to determine the incidence of primary stroke.
Results:
One hundred and four children, 53 males, and 51 females were enrolled into the study. Their ages ranged from 2 to 16 years with a mean of 6 years. At first TCD examination, velocities ranged from 173 to 260 cm/sec with conditional and abnormal risk velocities in 60 (57.7%) and 44 (42.3%) children, respectively. Follow up ranged from 1 to 8 years with a mean of 3.6 years. Mean TCD velocities showed a significant decline from 198.2 (standard deviation [SD] = 15.6) cm/sec to 169.3 (SD = 21.4) cm/sec (P < 0.001). One stroke event occurred in the cohort, giving a stroke incidence of 0.27/100 person years.
Conclusion:
HU significantly reduces TCD velocities in Nigerian children with SCD and elevated TCD velocities, with a corresponding reduction in the incidence of primary stroke. HU may represent a potential alternative for primary stroke prevention in low and middle income countries where the burden of SCD resides.
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