Screening for beta-thalassaemia carriers in Egypt: significance of the osmotic fragility test.
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.
El-Beshlawy
A
A
Department of Paediatrics, Faculty of Medicine, Cairo University, Cairo, Egypt. amalelbeshlawy@yahoo.com
Kaddah
N
N
Moustafa
A
A
Mouktar
G
G
Youssry
I
I
D000293:Adolescent; D000747:Anemia, Hypochromic / Q000453:epidemiology / Q000235:genetics; D018798:Anemia, Iron-Deficiency / Q000453:epidemiology / Q000235:genetics; D002648:Child; D003362:Cost-Benefit Analysis; D004534:Egypt / Q000453:epidemiology; D005319:Fetal Hemoglobin / Q000378:metabolism; D006580:Genetic Carrier Screening / Q000379:methods*; D005820:Genetic Testing / Q000191:economics / Q000379:methods* / Q000592:standards; D006443:Hemoglobin A2 / Q000378:metabolism; D006579:Heterozygote; D006776:Hospitals, Pediatric; D006785:Hospitals, University; D006786:Hospitals, Urban; D006801:Humans; D007501:Iron / Q000097:blood; D009996:Osmotic Fragility; D011159:Population Surveillance; D015995:Prevalence; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014168:Transferrin / Q000378:metabolism; D017086:beta-Thalassemia / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology* / Q000235:genetics
D014168:Transferrin; D006443:Hemoglobin A2; D005319:Fetal Hemoglobin; D007501:Iron