Hb S/?-Thalassemia in the REDS-III Brazil Sickle Cell Disease Cohort: Clinical, Laboratory and Molecular Characteristics.
Ontology highlight
ABSTRACT: We described the clinical, laboratory and molecular characteristics of individuals with Hb S (HBB: c.20A>T)/?-thalassemia (Hb S/?-thal) participating in the Recipient Epidemiology and Donor Evaluation Study (REDS-III) Brazil Sickle Cell Disease cohort. HBB gene sequencing was performed to genotype each ?-thal mutation. Patients were classified as Hb S/?0-thal, Hb S/?+-thal-severe or Hb S/?+-thal based on prior literature and databases of hemoglobin (Hb) variants. Characteristics of patients with each ?-thal mutation were described and the clinical profile of patients grouped into Hb S/?0-thal, Hb S/?+-thal and Hb S/?+-thal-severe were compared. Of the 2793 patients enrolled, 84 (3.0%) had Hb S/?0-thal and 83 (3.0%) had Hb S/?+-thal; 40/83 (48.2%) patients with Hb S/?+-thal had mutations defined as severe. We identified 19 different ?-thal mutations, eight Hb S/?0-thal, three Hb S/?+-thal-severe and eight Hb S/?+-thal. The most frequent ?0 and ?+ mutations were codon 39 (HBB: c.118C>T) and IVS-I-6 (T>C) (HBB: c.92+6T>C), respectively. Individuals with Hb S/?0-thal had a similar clinical and laboratory phenotype when compared to those with Hb S/?+-thal-severe. Individuals with Hb S/?+-thal-severe had significantly lower total Hb and Hb A levels and higher Hb S, white blood cell (WBC) count, platelets and hemolysis markers when compared to those with Hb S/?+-thal. Likewise, individuals with Hb S/?+-thal-severe showed a significantly higher occurrence of hospitalizations, vaso-occlusive events (VOE), acute chest syndrome (ACS), splenic sequestration, blood utilization, and hydroxyurea (HU) therapy.
SUBMITTER: Belisario AR
PROVIDER: S-EPMC7225056 | biostudies-literature |
REPOSITORIES: biostudies-literature
ACCESS DATA