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Objective: To establish a new indicator derived from reticulocyte hemoglobin (Ret-He) content and red blood cell (RBC) indices for screening for iron deficiency anemia (IDA) in an area in whch thalassemia is prevalent., Methods: Blood specimens from 304 women aged between 18 and 30 years residing in northeast Thailand were collected and measured for RBC and reticulocyte parameters. Iron deficiency was diagnosed when a participant had a serum ferritin level of less than 15 ng per mL. Thalassemia genotypes were defined by hemoglobin (Hb) and DNA analyses., Results: Of the total participants, 25% had iron deficiency (ID) and 50% carried the thalassemia gene. Various mathematical formulas were established and analyzed using the receiver operating characteristic (ROC) curve. The formula derived from Ret-He: (Ret-He/RDW-SD) × 10, was the best predictor for identifying ID among participants (area under the curve [AUC] = 0.812). Further testing of this indicator among individuals with positive thalassemia-screening results revealed stronger performance with an AUC of 0.874., Conclusions: The findings indicate that the formula derived from Ret-He might be applicable for screening ID in areas in which thalassemia is prevalent., (© American Society for Clinical Pathology 2020. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

This study assessed thalassemia and hemoglobinopathies in a group of the Tay ethnic minority. Participants included 289 women of reproductive-age who enrolled in a pilot screening program for thalassemia conducted at six communities of Thai Nguyen Province, northern Vietnam. Standard procedures including complete blood count (CBC), hemoglobin (Hb) and DNA analyses were performed for all samples. The prevalence of thalassemia in 289 Tay women was 15.6% (gene frequency 0.078) for α 0 -thalassemia (α 0 -thal), 10.0% (gene frequency 0.050) for α + -thal, 7.3% (gene frequency 0.036) for β-thalassemia (β-thal), 2.4% (gene frequency 0.012) for Hb Constant Spring [Hb CS; α142, Term→Gln, T AA> C AA (α2), HBA2 : c.427T>C] and 1.7% (gene frequency 0.009) for Hb E [β26(B8)Glu→Lys, G AG> A AG; HBB : c.79G>A]. Further analysis of β-globin gene abnormalities identified four mutations including codons 41/42 (-TCTT) ( HBB : c.126_129delCTTT), codon 17 (A>T) ( HBB : c.52A>T), codons 71/72 (+A) ( HBB : c.216_217insA), and -28 (A>G) ( HBB : c.78A>G). The results hint at the remarkably high frequencies of severe forms of thalassemia that indicate a serious public health problem requiring further exploration, and most probably, also intervention within the country.

Screening for thalassemia carriers should not only be conducted in middle-income countries but also can be possible in low-middle income countries, through cooperation of experienced professionals from middle income countries. We describe a collaborating model between two close neighboring countries in establishing such a screening program for thalassemia. After training and setting up of facilities, a total of 152 out of 187 hospital staff were screened as a pilot activity to encourage community participation. Referring system for sending blood samples to a reference center in Thailand was also established. Among 152 health staff, 12.5% α0-thal, 2% β-thal and 13% Hb E carriers were found. Applying thalassemia screening to 411 pregnant women and 71 spouses, 5 couples at risk of bearing a child of thalassemia disease were identified. The thalassemia screening program has a sensitivity of 99.5%, specificity of 77%, positive predictive value of 73%, and negative predictive value of 99.5%. Thus, it is possible to operate a thalassemia screening program with acceptable performance in a low-middle income country (Lao People’s Democratic Republic) with the cooperation of a referral center located within close proximity in a middle income country (Thailand).

Background and Aims: A pilot screening program for thalassemia was initiated in the Lao People's Democratic Republic. This study aimed to describe the genotype diversity and hematologic features of thalassemia among the participating pregnant women., Methods: Blood samples of 411 pregnant Laotian women were collected. Hemoglobin (Hb) profiles were determined using a capillary zone electrophoresis system. Mutations of α- and β-globin genes were investigated using a polymerase chain reaction and related techniques., Results: As many as 26 different thalassemia genotypes including non-transfusion-dependent thalassemia, i.e. Hb E-β-thalassemia, Hb H, and EA Bart's diseases, were identified. A variety of phenotypic expressions of hematologic features and Hb profiles were observed, including an unusual phenotype of Hb E-β0 thalassemia with 89.1% Hb E, 1.6% Hb F, and 9.3% Hb A2., Conclusions: The remarkable genotype-phenotype diversity indicates a need for careful laboratory interpretation in order to provide appropriate genetic counseling and care to the Laotian population., (© 2015 S. Karger AG, Basel.)

The study was conducted to assess the achievement of a thalassemia screening program at a community level supported by village health volunteers (VHVs) of 2 subdistricts in the northeast of Thailand. One subdistrict served as the intervention and the other as the control area. A training program was organized for the village health volunteers from the intervention area. Essential information about the risk and danger of thalassemia was given to the participants who wanted to have children in the community as well. Of the 206 individuals who wanted to have children living in the intervention area, 190 (92.2%) agreed to undergo screening. Of the 196 individuals within the control area, only 26 (13.3%) voluntarily participated in the screening tests. Attitude toward prevention and knowledge about the disease improved significantly in both areas, but the differences between the scores were statistically significantly higher for individuals living in the intervention area., (© 2012 APJPH.)

Background and Aims: Information about the extent to which anemia is related to thalassemia and iron deficiency (ID) is not available in Vietnam. This study investigated the burden of anemia in relation to thalassemia and ID among Vietnamese pregnant women., Methods: A cross-sectional study was conducted in Thua Thien Hue, Central Vietnam. Blood samples taken from 399 pregnant women with a gestational age <12 weeks were analyzed. Anemia was defined as Hb levels <11 g/dl, and ID as ferritin values <15 ng/ml., Results: Out of 399 participants, 77 (19.3%) were anemic. While the prevalence of ID was 20.1%, the prevalence of ID anemia was 6.0%. The overall prevalence of thalassemia was 7.3%. Of the 77 anemic women, 24 (31.2%) had ID, and 20 (26.0%) had thalassemia genes. The rest (42.9%) were anemic due to unknown causes., Conclusions: The results indicate that ID remains a significant health burden among the study population, together with anemia caused by unknown factors. Thalassemias appear not to contribute to a great extent to anemia among Vietnamese pregnant women. Other causes need to be investigated further in order to develop an effective control program for anemia within the population., (Copyright © 2013 S. Karger AG, Basel.)

A community-based assessment of thalassemias and hemoglobinopathies was conducted at the Thua Thien Hue Province, Central Vietnam. By cluster sampling, a total of 410 pregnant women attending the antenatal care service at 30 commune health centers were recruited consecutively from September 2011 to June 2012. Hemoglobin (Hb) analysis was performed using an automated Hb analyzer. α-Thalassemia (α-thal) genes were identified by polymerase chain reaction (PCR)-based techniques. Out of the 410 pregnant women, 2.7% carried α(0)-thal and 1.2% were β-thal carriers. One woman with the - -(THAI) deletion was also found. Among the females under survey, structural Hb variants with 3.2% Hb E [β26(B8)Glu→Lys, GAG>AAG; HBB: c.78G>C] and 3.7% Hb Constant Spring [Hb CS; α142, Term→Gln, TAA>CAA (α2); HBA2: c.427T>C] were found. Assessing the frequency of thalassemias and hemoglobinopathies by ethnicity, Kinh (Vietnamese) and ethnic minority groups, Hb CS with a high frequency of 24.0% was observed in the ethnic minority groups. These results provide basic population-based information, are useful not only for implementing measures for prevention and control of thalassemias in the region but also for studying the importance of thalassemias and hemoglobinopathies in ethnic minorities within Southeast Asia.

In order to determine the prevalence of thalassemia and hemoglobinopathies in different regions of northeast (NE) Thailand and Vientiane, Laos People's Democratic Republic (PDR), a total of 1,809 blood samples were collected consecutively from individuals attending antenatal care services at 11 community hospitals in different regions of NE Thailand and three hospitals in Vientiane, Laos PDR, from May 2009 to April 2010. All individuals were investigated for thalassemia and hemoglobinopathies using standard methods. For individuals from NE Thailand, the carrier frequencies were 41.7% for Hb E [β26(B8)Glu→Lys, GAG>AAG], 5.8% for α(0)-thalassemia (α(0)-thal), and 0.9% for β-thal. The THAI deletion type of α(0)-thal was found in one individual from an ethnic minority. From a group of pregnant Laotian women, 30.1% were Hb E carriers. The prevalence of α(0)-thal of 8.6% for the Laotian women was similar to that found in the upper northeastern part of Thailand. The frequency of β-thal was 2.3 %. The proportion of carriers of α(+)-thal and Hb Constant Spring (Hb CS, α142, Term→Gln (TAA>CAA in α2)] ) from Thailand and Laos was significantly different. The frequency of Hb Paksé [α142, Term→Tyr (TAA>TAT in α2)] was relatively low for Thailand as well as for Laos. The results indicate that thalassemia and hemoglobinopathies are a significant health burden in the region and that a prevention and control program for severe thalassemia diseases should be established in Laos.

Background and Aims: The study aimed to determine the proportion of iron deficiency (ID) anemia (IDA) among vegans in northeast Thailand and to explore whether mathematical formulas derived from red blood cell (RBC) indices are applicable for IDA screening in the study population., Methods: Blood samples from 234 individuals (age 6-45 years) living in a vegan community were taken. Complete blood cell count, serum ferritin, hemoglobin profiles and DNA analysis for α-thalassemia were determined. Anemia was defined using the WHO criteria adjusted for age and sex. Serum ferritin <15 ng/ml was considered as ID. A number of mathematical formulas derived from RBC indices were applied to screen ID among anemic individuals., Results: Anemia was found in 41.5% (95% CI = 35.1-48.1%) of the study participants. The overall proportion of thalassemia and hemoglobinopathies was 56.4% (95% CI = 49.8-62.9%). Of the anemic participants, 45.4% had ID. Based on the receiver-operating characteristic curve analysis, 4 formulas were applicable for predicting ID among anemic individuals (highest sensitivity of 86.4%)., Conclusions: The proposed formulas might be used as proxy indicators for the identification of ID among anemic children and adult vegans if more sophisticated laboratory determinations are not available due to limited financial resources., (Copyright © 2012 S. Karger AG, Basel.)

Unlabelled: The cross-sectional study assessed anemia, thalassemia, and hemoglobinopathies, as well as iron deficiency, among 190 northeastern Thai school children aged 10 to 11 years. The aim was to analyze the reasons for anemia among the group. Hemoglobin concentration and other hematological parameters were determined using an automated blood cell counter. Beta-thalassemia and other hemoglobinopathies were identified by high performance liquid chromatography (HPLC) analysis of hemoglobin. Alpha-thalassemia was identified by polymerase chain reaction (PCR) and related techniques. Iron deficiency was assessed using serum ferritin (SF) <20 ng/ml as indicator. Based on the WHO criteria, anemia was defined by hemoglobin (Hb) level <11.5 g/dl. Twenty five out of 190 children (13.2%; 95% CI = 8.7-18.8%) were anemic. Iron deficiency was found in only two out of 190 children (1.0%; 95% CI = 0.1-3.8%), but the two iron deficient children were not anemic. The proportion of thalassemia and hemoglobinopathies among the group was 61.1% (95% CI = 53.7-68.0%). As underlying reasons for anemia, thalassemia and hemoglobinopathies were found in 22 out of 25 (88.0%) anemic children. Beta-thalassemia and homozygous Hb E seem to be important, while this was less obvious for heterozygous α-thalassemia and heterozygous Hb E., Conclusion: The results suggest that thalassemia and hemoglobinopathies may be major contributing factors to the occurrence of anemia in this area among the children's population.

We determined the prevalence of the H63D and the IVS5#1G-A HFE mutations in 370 (169 males and 201 females) Thai thalassemia carriers and 201 normal subjects. While no IVS5#1G-A mutation was found, the H63D heterozygosity was identified in 5.5% (11/201) of normal subjects and 7.3% (27/370) of thalassemia carriers. Within the thalassemic group, the medians (ranges) of serum ferritin were 217.5 ng/ml (20.1-424.3) and 169.8 ng/ml (3.9-3,536.0) in male subjects and 30.4 ng/ml (11.9-130.7) and 49.3 ng/ml (0.6-931.0) in female subjects with (HD) and without (HH) H63D mutation, respectively. The proportions of subjects with elevated ferritin were found to be 37.5% (6/16) for HD and 14.0% (18/129) for HH in male and 0% (0/11) for HD and 3.0% (5/164) for HH in female subjects, respectively. Statistical analysis of all the data revealed no significant difference. Among 14 Hb E/beta-thalassemia patients, no difference in hematological data as well as serum ferritin levels was observed between those with (HD) and without (HH) H63D mutation. Therefore, the H63D heterozygosity has no significant effect on the serum ferritin level and screening for this HFE mutation in thalassemic patients is not recommended., (2007 S. Karger AG, Basel)

A cross-sectional prevalence study of anemia was undertaken on 412 pregnant women in northeast Thailand during January 2003 to May 2004. With standardized diagnostic protocols and the CDC criteria of anemia [hemoglobin (Hb) < 11 g/dl at < or = 12 weeks of gestation and Hb < 10.5 g/dl at < or = 20 weeks of gestation], 71 (17.2%) subjects were anemic. Of these, 42 (59.2%) subjects had thalassemia, 5 (7.0%) had iron deficiency, 18 (25.4%) had combined thalassemia and iron deficiency and 6 (8.5%) had no thalassemia nor iron deficiency. Adjusted logistic regression analyses indicated that various thalassemia genotypes were significantly related to anemia, while homozygous Hb E had the highest risk with an odds ratio (OR) of 44.8 (95% CI 12.6-159.7). In comparison, iron deficiency demonstrated a much lower risk with OR of 3.1 (95% CI 1.4-6.8). This finding suggests that the contribution of iron deficiency to pregnancy associated anemia in this region is low.

Primary screening for thalassemia and hemoglobinopathies usually involves an accurate blood count using an expensive electronic blood cell counter A cheaper alternative method was tested by using a modified osmotic fragility (OF) test and a modified dichlorophenolindophenol (DCIP) test. Altogether 423 pregnant Thai women participated in this project. Hemoglobin patterns and globin genotypes were determined using an automated high-performance liquid chromatography analyzer and polymerase chain reaction analysis of alpha- and beta-globin genes. Among the 423 subjects, 264 (62.4%) carried thalassemia genes. The combined OF and DCIP tests detected all pregnant carriers of the 3 clinically important thalassemias, ie, alpha0-thalassemia, beta-thalassemia, and hemoglobin E with a sensitivity of 100.0%, specificity of 87.1%, positive predictive value of 84.5%, and negative predictive value of 100.0%, which show more effectiveness than these values for the standard method based on RBC counts. A combination of modified OF and DCIP tests should prove useful and applicable to prenatal screening programs for thalassemia and hemoglobinopathies in communities with limited facilities and economic resources.