Secondary benefit of maintaining normal transcranial Doppler velocities when using hydroxyurea for prevention of severe sickle cell anemia

Abstract

In a retrospective cohort study, we tested the hypothesis that when prescribing hydroxyurea (HU) to children with sickle cell anemia (SCA) to prevent vaso-occlusive events, there will be a secondary benefit of maintaining low transcranial Doppler (TCD) velocity, measured by imaging technique (TCDi). HU was prescribed for 90.9% (110 of 120) of children with SCA ≥5 years of age and followed for a median of 4.4 years, with 70% (n = 77) receiving at least one TCDi evaluation after starting HU. No child prescribed HU had a conditional or abnormal TCDi measurement. HU initiation for disease severity prevention decreases the prevalence of abnormal TCDi velocities. K E Y W O R D Shydroxyurea therapy, red cells, sickle cell disease, transcranial Doppler velocity

Transcranial Doppler Ultrasound in Peninsular Arab Patients With Sickle Cell Disease

“…Local experience in the region shows that about one‐third of patients are taking hydroxyurea, which has been reported to lower TAMMV values in patients with SCD . Hydroxyurea therapy was documented only among the Iraqi cohort and showed significant lowering of the TAMMV in both the MCAs and PCAs, although the reverse was true in the ICAs.…”

Targeted Hydroxyurea Education after an Emergency Department Visit Increases Hydroxyurea Use in Children with Sickle Cell Anemia

“…For example, a center that “strongly recommends” hydroxyurea for all children with SCA 5 years or older recently reported that over 90% of their patients were on hydroxyurea. (13) The NHLBI guidelines state that families should be “offered” hydroxyurea; this may lead to ambiguous language from providers who offer, rather than recommend, treatment. Providers may also be communicating misgivings about hydroxyurea including concerns about carcinogenicity, teratogenicity, and adverse effects on fertility.…”

Intermittent or uneven daily administration of low‐dose hydroxyurea is effective in treating children with sickle cell anemia in Angola

“…acute pain events, observational studies also show that hydroxyurea increases baseline hemoglobin concentration, 6,8,14,15 decreases elevated transcranial Doppler (TCD) velocities, [16][17][18] reduces proteinuria or glomerular hyperfiltration, [19][20][21][22][23] may be effective in the primary and secondary prevention of stroke, [24][25][26][27] and may improve retinopathy, 28 hypoxemia, 29,30 obstructive sleep apnea, 31 priapism, 32 and general organ function. 33,34 Based on evidence of efficacy, an expert panel of the US National Heart, Lung, and Blood Institute (NHLBI) recently recommended that clinicians offer hydroxyurea to all adolescents, children, and infants who are at least 9 months old regardless of clinical severity to reduce complications due to SCA.…”

“…Additionally, the BABY HUG trial showed that hydroxyurea is safe to administer in infants as young as 9 months while decreasing the number of pain and dactylitis episodes . Besides acute pain events, observational studies also show that hydroxyurea increases baseline hemoglobin concentration, decreases elevated transcranial Doppler (TCD) velocities, reduces proteinuria or glomerular hyperfiltration, may be effective in the primary and secondary prevention of stroke, and may improve retinopathy, hypoxemia, obstructive sleep apnea, priapism, and general organ function …”