Trans-Cranial Doppler Ultrasound Velocity Measurements In Children With Sickle Cell Disease In Nairobi, Kenya

Background Children with Sickle Cell Disease (SCD) have a stroke lifetime risk of 25-30% and a peak incidence at 7 years of age. Current evidence recommends annual trans-cranial Doppler ultrasound (TCD) to screen for risk of stroke in children aged 2-16 years. Recent studies in sub-Saharan Africa (SSA) have reported much lower prevalence of velocities greater than 200cm/s in the context of similar incidence of stroke as in the west.

Methods We undertook a retrospective study of timed mean average cerebral blood flow velocity (CBFv) in children with SCD presenting to the SCD clinics across two sites: Gertrude’s Children’s Hospital and Uhai Neema Hospital. TCD had been undertaken on patients referred for the procedure, applying standard protocols. We documented occurrence of stroke in these children.

Results We retrieved data for 85 children; they were of median age 8 (IQR 4-12) years, and 42% (n=36) were females. The left CBFv measurements was of average 102(IQR 94-111) cm/S; and the right CBFv was 104(IQR 96, 110) cm/S. One child had left CBFv>200cm/S. Four children had conditional left CBFv (>175cm/S). Four children had right ≤CBFv 50cm/S and six had left CBFv≤50cm/S. Six children had suffered stroke; and in five of them, we were not able to insonate the corresponding MCA.

Conclusion CBFv observations in our patient group is of a similar profile to that of children in other African countries. There is need to re-examine the CBFv values for children with SCD residing in SSA.

Disclosures All authors declare no conflict of interest