5613304 ANTENATAL SCREENING FOR HAEMOGLOBINOPATHIES AMONG THE TRIBAL POPULATION IN THE STATE OF TAMIL NADU, INDIA

Abstract

Background: Hemoglobinopathies especially Sickle cell anemia and Thalassemia is more prevalent in the tribal population living in the hilly areas of Tamilnadu. As a part of the Government initiative for prevention of hemoglobinopathy, National Health Misiion, Tamilnadu State Chapter, has initiated Hemoglobinopathy screening for antenatal mothers in this target population. It was anticipated to have challenges like difiiculites in convincing the families for screening and if required aminocentesis. The study details with results of this screening program conducted over the period of 9 months is being presented. The project is ongoing till date. Aim: To prevent the prospective birth of Thalassemia and Sickle Cell Anemia children in Hemoglobinopathy prevalent tribal population Study Period: From September 2021 to June 2022 Methodology: All Antenatal Mothers attending the Primary health centres (PHC - Government Health Facilities) in 18 tribal blocks were screened for Haemoglobinopathies (Thalassemia & SCA) during the first trimester. 4 ml of blood was taken, 2 ml each in EDTA tubes. Informed consent was obtained before taking blood samples for test. Complete Blood Count was done in the Primary Health Centre. The second sample was transported under cold chain to the nearest medical college on the same day where high performance liquid chromatography (HPLC) was done. The CBC reports of all the mothers screened were shared with the Biochemistry Department where HPLC was done in the Biorad - 10 machine. If the mothers were found to have Thalassemia or Sickle Cell trait, husbands were tested for CBC & HPLC. If the couple was positive they were given genetic counselling regarding amniocentesis at the PHC with online support of specialists including Hematologist, State Blood Diseases Expert, and Genetics Consultant. If the couple give their consent, amniocentesis was done between 16 – 20 weeks at the prenatal diagnostic centre at state Capital, Chennai. Genetic testing was done for the parents and the foetus. This test was outsourced. If the foetus was found to be affected post test counselling was given regarding Medical Termination of Pregnancy (MTP) if they gave consent MTP was done. If the foetus was normal or to have trait, pregnancy was continued. Results: Total Mothers screened - 14016 Antenatal (AN) mothers Prevalence of Hemoglobinopathy Trait/ diseased - 7 % (959) Various types of Hemoglobinopathy trait/ diseased among the screened AN Mothers - Thalassemia trait (40.8%), Sickle cell trait (27.6 %), Sickle Cell Anemia (2%), Borderline thalassemia trait (29.6 %) No of husbands screened 511 out of which 13 % (73) were positive No of Amniocentesis done in 38 antenatal mothers out of which 31.58 % (12) were normal foetus, Trait Foetus 47.37 % (18), affected & MTP done 21.05 % (8) Conclusion: Antenatal Screening & Diagnosis is the best strategy for preventing Haemoglobinopathies which will be cost effective in the long term. It proactively reduces morbidity, mortality, DALY & psychological problems seen in management of affected children & their families. The direct medical cost of treating 1 Thalassemia child weighing 30 kg is around 2500 USD per year along with significant indirect expenses where as the cost of Antenatal Screening & Prenatal Diagnosis is 225 USD. The challenges met in implementing the program including difiiculty in taking the husband’s sample and counseling the couple with affected fetus are addressed. Reference 1. S Chakravorty, MC Dick. Antenatal Screening for Heamoglobinopathies; current status, barriers and ethics. Br J Haematol 2019; 187(4):431-440. doi: 10.1111/bjh.16188. Epub 2019 Sep 11.