Multicenter validation of fully automated capillary electrophoresis method for diagnosis of thalassemias and hemoglobinopathies in Thailand.

Thalassemias and hemoglobinopathies are highly prevalent in Thailand and other Southeast Asian countries. Accurate and precise separation of hemoglobin types, together with reliable quantitation, are essential for differential diagnosis of these diseases. Presented in this study is a multicenter validation of a fully automated capillary electrophoresis (CE) method for hemoglobin separation and quantitation involving four reference laboratories in Thailand. Analytical performance characteristics, including precision and accuracy were compared with existing validated HPLC and LPLC methods using 412 blood samples from unrelated subjects. Coefficient of variance of Hb A2 quantitation was 1.80-2.86, 1.26-5.13 and 1.08-6.66% for within run, between run and interlaboratory comparison, respectively. Results of Hb A2 and Hb F quantitated by the CE method correlates well with those of the two comparative methods (r = 0.98-0.99). The CE method correctly determined the genotypes (thalassemias and hemoglobin variants) of all blood samples tested. The major advantage of the CE system is its ability to separate and quantitate Hb A2, Hb E, Hb F, Hb H and Hb Bart's, which are important parameters required for diagnosis of thalassemias and hemoglobinopathies.

The validation of an automated liquid chromatography system for the diagnosis of thalassemias and hemoglobinopathies.

Accurate and precise hemoglobin separation and the quantitation of Hb A2 and Hb F are essential for the diagnosis of the thalassemias and hemoglobinopathies. Presented in this study is the validation of the the Hb A2 assay of the HbGold analyzer, a fully automated liquid chromatography system for hemoglobin separation and quantitation. Variability of Hb A2 quantitation was quite low; the CV's of within-run, between-run and interlaboratory studies were 1.8-3.1%, 3.4-6.0% and 6.8-8.8% respectively. The results of the %Hb A2 quantitated by HbGold analyzer correlated well with those given by the Bio-Rad Variant Hb testing system (r=0.98). The application of the HbGold analyzer for the diagnosis of the thalassemia phenotypes frequently observed in Thailand is considered. In conclusion, the Hb A2 assay of the HbGold analyzer could be used for the quantitation of Hb A2 and Hb F and the presumptive identification of abnormal hemoglobins.

Prevention of thalassemia: experiences from Samui Island.

Thalassemia is one of the most important genetic disorders in Thailand. A model for prevention of thalassemia by combining 4 strategies including education, carrier screening, counseling and prenatal diagnosis was developed by a thalassemia task force. A thalassemia work group was formed in order to develop a mechanism to integrate the model for real use on Samui Island where thalassemia is common and a specific disease oriented program is required. 200 health professionals working on Samui Island participated in the thalassemia educational courses. The specific training courses were also provided for obstreticians, medical technologists and counselors. A team of well-trained health professionals was established to manage public education. Information booklets, posters, brochures and mass media including spot radio and newspapers were used as educational materials. For carrier screening, blood samples of pregnant women from all health care organizations on Samui Island were collected and screened for thalassemia carriers by using the osmotic fragility (OF) test/the dichlorophenol indophenol precipitation (DCIP) tests at Samui Hospital. Samples with positive results were sent to the Regional Medical Sciences Center in Surat Thani for thalassemia diagnosis. When a carrier was identified, her spouse was offered testing. For at-risk couples, details of the disorder were included in counseling to help them reach a decision that was right to them, in the context of their unique medical, moral and social situations. Amniotic fluid samples were collected for prenatal diagnosis. All patient information was registered by using computer software. After 1 year of integration by using facilities of the Ministry of Public Health service system, a wide range of problems were identified. They underlined the need for effective health service structure co-operation, adequate education of responsible health professionals, explicit policies and a clear line of responsibility at local, regional and national levels for service development and quality management. It is hoped that all information conducted in the present study will be useful to health authorities to develop an explicit policy and promote the health service structure co-operation in the country that will finally lead to successfully reducing the frequency of severe thalassemia in the future.

Prevention of thalassemia: experiences from Samui Island.

Thalassemia is one of the most important genetic disorders in Thailand. A model for prevention of thalassemia by combining 4 strategies including education, carrier screening, counseling and prenatal diagnosis was developed by a thalassemia task force. A thalassemia work group was formed in order to develop a mechanism to integrate the model for real use on Samui Island where thalassemia is common and a specific disease oriented program is required. 200 health professionals working on Samui Island participated in the thalassemia educational courses. The specific training courses were also provided for obstreticians, medical technologists and counselors. A team of well-trained health professionals was established to manage public education. Information booklets, posters, brochures and mass media including spot radio and newspapers were used as educational materials. For carrier screening, blood samples of pregnant women from all health care organizations on Samui Island were collected and screened for thalassemia carriers by using the osmotic fragility (OF) test/the dichlorophenol indophenol precipitation (DCIP) tests at Samui Hospital. Samples with positive results were sent to the Regional Medical Sciences Center in Surat Thani for thalassemia diagnosis. When a carrier was identified, her spouse was offered testing. For at-risk couples, details of the disorder were included in counseling to help them reach a decision that was right to them, in the context of their unique medical, moral and social situations. Amniotic fluid samples were collected for prenatal diagnosis. All patient information was registered by using computer software. After 1 year of integration by using facilities of the Ministry of Public Health service system, a wide range of problems were identified. They underlined the need for effective health service structure co-operation, adequate education of responsible health professionals, explicit policies and a clear line of responsibility at local, regional and national levels for service development and quality management. It is hoped that all information conducted in the present study will be useful to health authorities to develop an explicit policy and promote the health service structure co-operation in the country that will finally lead to successfully reducing the frequency of severe thalassemia in the future.

The validation of an automated liquid chromatography system for the diagnosis of thalassemias and hemoglobinopathies.

Accurate and precise hemoglobin separation and the quantitation of Hb A2 and Hb F are essential for the diagnosis of the thalassemias and hemoglobinopathies. Presented in this study is the validation of the the Hb A2 assay of the HbGold analyzer, a fully automated liquid chromatography system for hemoglobin separation and quantitation. Variability of Hb A2 quantitation was quite low; the CV's of within-run, between-run and interlaboratory studies were 1.8-3.1%, 3.4-6.0% and 6.8-8.8% respectively. The results of the %Hb A2 quantitated by HbGold analyzer correlated well with those given by the Bio-Rad Variant Hb testing system (r=0.98). The application of the HbGold analyzer for the diagnosis of the thalassemia phenotypes frequently observed in Thailand is considered. In conclusion, the Hb A2 assay of the HbGold analyzer could be used for the quantitation of Hb A2 and Hb F and the presumptive identification of abnormal hemoglobins.