ABSTRACT
To estimate beta-thalassaemia carrier rate and to determine an accurate mass screening test, we tested 1000 randomly selected children aged 5-16 years from different geographical areas of Egypt. Microcytosis was present in 412 participants. The osmotic fragility test was positive in 81.1% of the 90 beta-thalassaemia carriers; in the indeterminate group (12 participants), the test was positive in 83.3%; in the 310 who were iron deficient, the test was positive in 63.9%. beta-thalassaemia carrier rate was > or = 9%. Serum iron, microcytosis, HbA2 level and transferrin saturation were accurate tests for detecting carriers. For the one-tube osmotic fragility test, sensitivity was 87.0% and specificity 34.1%; the test has limited use for a mass screening programme in Egypt, where iron deficiency is prevalent.
Subject(s)
Genetic Carrier Screening/methods , Genetic Testing/methods , Osmotic Fragility , beta-Thalassemia/diagnosis , beta-Thalassemia/epidemiology , Adolescent , Anemia, Hypochromic/epidemiology , Anemia, Hypochromic/genetics , Anemia, Iron-Deficiency/epidemiology , Anemia, Iron-Deficiency/genetics , Child , Cost-Benefit Analysis , Egypt/epidemiology , Fetal Hemoglobin/metabolism , Genetic Testing/economics , Genetic Testing/standards , Hemoglobin A2/metabolism , Heterozygote , Hospitals, Pediatric , Hospitals, University , Hospitals, Urban , Humans , Iron/blood , Population Surveillance , Prevalence , Sensitivity and Specificity , Severity of Illness Index , Transferrin/metabolism , beta-Thalassemia/blood , beta-Thalassemia/geneticsABSTRACT
To estimate beta-thalassaemia carrier rate and to determine an accurate mass screening test, we tested 1000 randomly selected children aged 5-16 years from different geographical areas of Egypt. Microcytosis was present in 412 participants. The osmotic fragility test was positive in 81.1% of the 90 beta-thalassaemia carriers; in the indeterminate group [12 participants], the test was positive in 83.3%; in the 310 who were iron deficient, the test was positive in 63.9%. beta-thalassaemia carrier rate was >/= 9%. Serum iron, microcytosis, HbA2 level and transferrin saturation were accurate tests for detecting carriers. For the one-tube osmotic fragility test, sensitivity was 87.0% and specificity 34.1%; the test has limited use for a mass screening programme in Egypt, where iron deficiency is prevalent