Hydroxyurea Therapy in Hemoglobin Madrid Patients / 대한혈액학회지

ABSTRACT

Unstable hemoglobins (Hb) are variants of adult Hb that tend to precipitate and form insoluble inclusions (Heinz bodies) within red blood cells (RBC) and RBC precursors. More than 100 structurally different unstable Hb variants showing broad spectrum of manifestations from asymptomatic to severe hemolytic anemia and dyserythropoiesis have been discovered. Hydroxyurea is a potent ribonucleotide reductase inhibitor and have been proposed as a new therapy for beta chain hemoglobinopathies through activation of gamma chain synthesis. We treated two patients (A : son, B : father) with highly unstable Hb diagnosed as Hb Madrid [Beta 115(G17)Ala->Pro] by direct DNA sequencing and restriction enzyme analysis. Our patients received hydroxyurea in dosages varying from 0.75g to 1.3g daily for 89 weeks. We could not show the clinical and hematological improvements after hydroxyurea therapy in thses patients. Optimization of dosage and long term side effects of hydroxyurea should be studied further.