Outcome of The Prenatal Beta-Thalassemia Control Program
Keywords:
Beta-thalassemia genes, Genetic counseling, Prenatal diagnosisAbstract
Beta thalassemia (β-thalassemia) is an inherited hemoglobin disorders and can be found in
Thailand. β-thalassemia can be found in 3-9% of Thai population and 13% approximately abnormal hemoglobin E (HbE), which is found mostly in northeastern Thai population. As a result, Thai couples are at risk of giving birth to babies with β-thalassemia major. The objective of this study was to develop a program for control and prevention of β-thalassemia. This retrospective descriptive research collected data from medical records and DNA β-thalassemia records at Khon Kaen Hospital during October, 2016-September, 2018. A total 6,151 couples were screened for thalassemia using complete blood count (CBC) and dichlorophenol indophenols precipitation test (DCIP). All positive screening samples were confirmed by hemoglobin typing (HPLC) and reverse dot blot hybridization (RDB) analysis using β-thalassemia test kit (Southeast Asia Panel, SEA) 22 panels
which was a new technique. Only one blood tube was used in the entire process from screening
through the molecular confirmation. Couples at risk were assessed by clinician and referred to genetic counseling, prenatal diagnosis and/or termination. The screening tests classified 235 (3.82%) couples as β-thalassemia carriers (MCV<80 fl and MCH<27 pg). Genes that cause thalassemia
major were found in 92 (1.5%) couples based on molecular confirmation. After genetic counseling
and prenatal diagnosis, 14 (0.23%) fetuses with β-thalassemia major were found. Thirteen couples (0.21%) made decision to terminate their fetuses and only one couple made decision to continue the pregnancy (β0-thalassemia/HbE) and planned to receive bone marrow transplantation in the future. In conclusion, the program established in this study is effective for control and prevention of
β-thalassemia by reducing number of new cases with these diseases. This program can suggest a guideline to prevent the birth of babies with β-thalassemia major and related issues.
