Antenatal screening for thalassemia carrier at tertiary care centre
Keywords:Mentzer index, Thalassemia minor, Universal screening
Background: Thalassemia syndromes are the commonest genetic disorders of blood and constitute a vast public health problem with 2.78 to 4% prevalence in India. The most effective and feasible approach to reduce the incidence of thalassemia major is implementation of carrier screening program to screen the antenatal women in early pregnancy.
Methods: Institutional based cross sectional observational study was conducted. We screened 400 antenatal women by performing preliminary test red cell indices, Mentzer index and confirmatory test by high performance liquid chromatography. Husbands of positive women were also tested to find out couples on risk.
Results: Out of 400 antenatal women screened, 46 required HbA2 estimation, and 11 (2.8%) were diagnosed as β-thalassemia minor positive. Most of thalassemia minor positive women were primigravida and mean (SD) age and gestational age of these women was 23.8 (3.1) years and 11.8 (1.7) weeks, respectively. Amongst thalassemia minor positive women most were mild to moderately anemic and these women had significantly greater mean TRBC count. Ninety one percent of thalassemia minor positive women had MCV<77. All of thalassemia minor positive women had MCH<27. Eighty two percent of thalassemia minor positive women had MI<13. None of couple at-risk was detected. So, prevalence of thalassemia carrier was 2.8%.
Conclusions: Thalassemia is a monogenetic disorder with autosomal recessive streak. Universal screening in antenatal window by complete blood counts, hematological indices (MCV, MCH, TRBC), Mentzer index and HPLC may lead to non-pyrrhic victory over this odious entity.
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