The Complete Management Of Thalassemia And Thalassemia Syndromes
With A Thalassemia Patient
In a population where genes for abnormal hemoglobin and thalassemia are present, random mating gives rise to offsprings carrying both the abnormal genes. Such double heterozygocity may lead to Hb E thalassemia, Hb S thalassemia and so on. The term thalassemia syndrome is used to include these double heterozygote conditions as well as the classical homozygous thalassemia. The double heterozygote states present with milder manifestations. Compared to thalassemia major. In such subjects, the presence of abnormal hemoglobin as well as the elevation of fetal hemoglobin can be demonstrated by suitable tests.
Lepore hemoglobins are formed when normal alpha chains combine with chains consisting of the N-terminal residues of delta chains. Three variants of Hb Lepore have been identified. In the homozygous state, clinical picture is that of Cooley’s anemia, the hemoglobin consisting of 75% Hb F and 25% Hb Lepore.
Hereditary persistence of fetal hemoglobin (HPFH)
In this condition, the gene for Hb F persists beyond the neonatal period, resulting In the production of large amounts of Hb F throughout life. The hematological picture varies. In homozygous subjects, Hb F forms 100% and in heterozygous, about 25%. Except for slight morphological abnormalities of erythrocytes, the clinical picture is almost normal. It is important to distinguish them from thalassemia syndromes which have different courses and prognosis.
Faulted Hemoglobin In Thalassemia
Blood transfusion is the mainstay of therapy. If Hb level is maintained above 10.0g/dl all the time by regular transfusions, erythroid hyperplasia does not occur. If the treatment is started early, skeletal deformities are prevented and growth and development continue normally. When the hemoglobin rises, intestinal absorption of Iron is reduced. However, Iron overload still occurs and this has to be treated by administering the Iron chelating agent desferrioxamine. Desferrioxamine is more effective in mobilizing Iron and eliminating it in Urine, if given by slow subcutaneous infusion than as intravenous bolus injections. It is given in the dose of 1 g/day as slow subcutaneous infusion overnight, several times a week. Administration of vitamin C before giving desferrioxamine increases the excretion of Iron.
A novel approach is the use of drugs like 5-azacytidine which are capable of inducing cellular differentiation and activation of repressed genes in tissue culture studies. This drug has been given in experimental studies as an infusion in a dose of 2 mg/Kg/day. Gamma chain synthesis is augmented. This helps in reducing the imbalance between alpha chains and non-alpha chains to form Hb F.
Thalassemia intermedia and thalassemia minor follow a milder course. They have to be diagnosed by laboratory studies.
© 2014 Funom Theophilus Makama