Optimizing Transcranial Doppler Screening for Stroke Prevention in Young African Children With Sickle Cell Disease

Abstract

BACKGROUND: The greatest burden of sickle cell disease (SCD) globally occurs in sub-Saharan Africa, where significant morbidity occurs secondary to SCD-induced vasculopathy and stroke. Transcranial doppler (TCD) ultrasound grades the severity of vasculopathy, with disease modifying therapy resulting in stroke risk reduction in high-risk children. The feasibility and utility of TCD screening in young children with SCD remains understudied. PROCEDURE: We performed a retrospective review of TCD examination results in children ≤24 months with SCD in one of six centers in Africa. Using the time-averaged maximum of the mean flow velocity, values <170 cm/s were considered to be low risk for stroke, 171-199 cm/s conditional risk, and >200 cm/s high risk. RESULTS: A total of 115 children were screened, with five (4.3%) unable to complete the TCD due to agitation. A total of 110 children with a mean age of 15 ± 5 months were included. Low risk studies were identified in 95 (86.4%) and conditional risk in 15 (13.6%). No patient had a high risk study. Those with conditional risk examinations were not more anemic than those with low risk studies (p = 0.84). CONCLUSIONS: TCD screening of young children with SCD is feasible, with low technical failure rates. Many children in our cohort had a conditional risk study, suggesting cerebral vasculopathy begins at a young age in some African children. Future large cohort studies should be undertaken to determine the incidence of conditional or high risk studies in African children ≤2 years with SCD to inform future guideline development for TCD screening.