Long-term treatment follow-up of children with sickle cell disease monitored with abnormal transcranial Doppler velocities

Stroke risk in sickle cell anemia (SCA), predicted by high transcranial Doppler (TCD) velocities, is prevented by transfusions. We present the long-term follow-up of SCA children from the Creteil newborn cohort (1992-2012) detected at risk by TCD and placed on chronic transfusions. Patients with normalized velocities and no stenosis were treated with hydroxyurea, known to decrease anemia and hemolytic rate. Trimestrial Doppler was performed and transfusions restarted immediately in the case of reversion to abnormal velocities. Patients with a genoidentical donor underwent transplant. Abnormal time-averaged maximum mean velocities (TAMMV) >= 200 cm/s were detected in 92 SCA children at a mean age of 3.7 years (range, 1.3-8.3 years). No stroke occurred posttransfusion after a mean follow-up of 6.1 years. Normalization of velocities (TAMMV < 170 cm/s) was observed in 83.5% of patients. Stenosis, present in 27.5% of patients, was associated with the risk of non-normalization (P < .001). Switch from transfusions to hydroxyurea was prescribed for 45 patients, with a mean follow-up of 3.4 years. Reversion, predicted by baseline reticulocyte count >= 400 x 10(9)/L (P < .001), occurred in 28.9% (13/45) patients at the mean age of 7.1 years (range, 4.3-9.5 years). Transplant, performed in 24 patients, allowed transfusions to be safely stopped in all patients and velocities to be normalized in 4 patients who still had abnormal velocities on transfusions. This long-term cohort study shows that transfusions can be stopped not only in transplanted patients but also in a subset of patients switched to hydroxyurea, provided trimestrial Doppler follow-up and immediate restart of transfusions in the case of reversion.