Anemia, iron deficiency and thalassemia among adolescents in Northeast Thailand: results from two independent surveys

Development of molecular diagnostic platform for α0 -thalassemia 44.6 kb (Chiang Rai, --CR ) deletion in individuals with microcytic red blood cells across Thailand

INTRODUCTION

The α⁰ -thalassemia 44.6 kb or Chiang Rai (--^CR ) deletion has been reported in northern Thailand and is capable of causing hemoglobin (Hb) H disease and a lethal α-thalassemia genotype, Hb Bart's hydrops fetalis, in this region. However, there are no current data regarding the frequency of --^CR nationwide due to a lack of effective diagnostic assay. Therefore, this study aimed to develop a reliable platform for simultaneous genotyping of --^CR and two common α⁰ -thalassemias in Thailand (--^SEA and --^THAI ) and investigate the frequency of --^CR across Thailand.

METHODS

Multiplex gap-PCR assay and five renewable plasmid DNA controls for --^CR , --^SEA , --^THAI , α2-globin (HBA2), and β-actin (ACTB) were newly developed and validated with reference methods. The developed assay was further tested on 1046 unrelated individuals with a reduced mean corpuscular volume (MCV) of less than 75 fl for investigating genotypic and allelic spectrum of --^CR .

RESULTS

Our developed assay showed 100% concordance with reference methods. The results were valid and reproducible throughout hundreds of reactions. Comparison of the genotypic and allelic spectra revealed that heterozygous --^SEA (--^SEA /αα) and --^SEA alleles were dominant with the frequency of 22.85% (239/1046) and 13.34% (279/2092), respectively. Of these, --^THAI and --^CR were relatively rare in this population and comparable to each other with the allelic frequency of 0.14% (3/2092).

CONCLUSION

This study successfully established a reliable molecular diagnostic platform for genotyping of --^CR , --^SEA , and --^THAI in a single reaction. Additionally, we demonstrated the frequency of --^CR in Thailand for the first time and provided knowledge basis for the planning of severe α-thalassemia prevention and control programs in Thailand, where thalassemia is endemic.

Anemia, iron deficiency, and thalassemia among the Thai population inhabiting at the Thailand-Lao PDR-Cambodia triangle

Anemia is a major public health problem in many areas of Southeast Asia. Ascertaining anemia and defining its underlying causes is essential for providing appropriate care, management, and establishment of a control program. Limited studies on these have been carried out on people living at the borders of Thailand, Lao PDR, and Cambodia. This cross-sectional study was done in four areas along the borders of Thailand, Lao PDR, and Cambodia. Blood specimens were collected from subjects aged 15-18 years in four districts including Kantharalak, Si Sa Ket province (n = 36), Nam Khun (n = 109), Nam Yuen (n = 98), and Na Chaluai (n = 128), Ubon Ratchathani province, Thailand. RBC parameters were recorded, and serum ferritin (SF) level was measured. Diagnosis of thalassemia and hemoglobinopathies was based on hemoglobin (Hb) and DNA analyses. Measurement of C-reactive protein was performed to exclude false-negative result of iron deficiency. The prevalence of anemia was found to be 25.1%. ID accounted for only 10.5%. Various types of thalassemia were identified in 67.7% of the subjects. The overall prevalence of thalassemia included 3.5% α⁰-thalassemia, 0.8% β-thalassemia, 47.7% Hb E, and 53.6% α⁺-thalassemia. The proportions of ID, thalassemia and combined ID and thalassemia among anemic subjects were 6.5%, 66.6%, and 20.4%, respectively. The results indicate that thalassemia and hemoglobinopathies rather than ID are major causes of anemia in Thailand-Lao PDR-Cambodia triangle. This information should prove useful for implementing an anemia control program in the regions.

Coexisting Iron Deficiency Anemia and Thalassemia Traits in Infants: Implication for an Anemia Screening Program

OBJECTIVES

To study the prevalence of anemia among healthy infants, and outcomes of giving a therapeutic trial of iron to anemic infants in thalassemia-endemic area.

METHODS

A cross sectional study was conducted in 6-9-month-old, full-term healthy infants who attended the well child clinics at 2 tertiary care centers in southern Thailand. Complete blood count and serum ferritin were performed in every infant, and hemoglobin typing was performed only in anemic cases. All anemic infants were given a therapeutic trial of iron and categorized into either; iron responder (hemoglobin increased ≥ 1 g/dL) or iron non-responder (hemoglobin increased <1 g/dL) groups after one month of the therapeutic trial. Mean levels of hematological parameters, including the Mentzer index, were compared within the groups.

RESULTS

A total of 620 infants were included in the study. From this, 230 infants (37%) were anemic for which iron deficiency contributed for 80% of the etiology. The iron responder group showed significant improvement in hematological parameters after a trial of iron, while there was no improvement in the iron non-responder group. Among iron responders, there were 31 out of 186 infants (16.6%) who had coexisting abnormal hemoglobin typing, and their post-treatment complete blood count still showed a mean corpuscular volume < 70, with a Mentzer index < 13.

CONCLUSION

Iron deficiency remains a major cause of anemia among infants, and a therapeutic trial of iron is beneficial in this age group, even though thalassemia trait/hemoglobinopathy can co-exist.

Severe microcytosis in a hemoglobin E/Β-thalassemia patient with signs of iron deficiency: A case report

Background

β-thalassemia is a hereditary disorder characterized by a decrease in the synthesis of β-globin chains that decreases hemoglobin in erythrocytes, low erythrocyte production, and anemia.

Case presentation

A 6-year-old girl came with complaints of paleness for one week. Physical examination showed vital signs within normal limits, conjunctival anemia, and hepatomegaly. Investigations: HGB 5.4 g/dL, MCV 44.5 fL, MCH 15.5 pg, MCHC 34.8 g/dL, RDW-CV 29.2%, WBC 4,770/μL, PLT 2,728,000/μL, Serum iron 29 g/dL, TIBC 217 g/dL and transferrin saturation of 13.36%. Peripheral blood smears showed target cells, teardrop cells, ovalocytes, fragmentocytes, cigar cells, and pseudothrombocytosis by automated hematology tools caused by the misinterpretation of small erythrocytes as platelets. Hemoglobin electrophoresis showed a decrease in HbA (4.9%), as well as an increase in HbF (18.3%), HbE (70.5%), and HbA2 (6.3%). The patient was diagnosed with β-thalassemia.

Discussion

Thalassemia with severe microcytosis suggests possible coexistence with iron deficiency. A complete iron profile examination is required in these patients to ensure appropriate and comprehensive medical management.

Conclusion

Iron profile examination plays an essential role in the management and diagnosis of β-thalassemia patients.

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The iron profile investigation should be considered in patients with β-thalassemia.

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Diagnosis of β-thalassemia with microcytosis can be given a blood transfusion.

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PCR transfusion can be considered in managing anaemia in children with β-thalassemia.

Prevalence and Associated Factors of Anemia among Muslim Students, Nakhon Si Thammarat, Thailand: A Cross-Sectional Study

Anemia is a global public health problem. The prevalence of anemia among different ages, genders or ethnic groups must be clarified in order to solve problems. This study proposed to determine the prevalence and factors related to anemia among the Muslim school-age population in Nakhon Si Thammarat, Thailand. Socio-demographic and anthropometric data were collected by a structured questionnaire. Blood samples were collected from 200 school-age subjects. The thalassemia screening was performed with KKU-OF and KKU-DCIP reagents. The prevalence of anemia in this study was 36.5%, divided into males and females, 33.3% and 39.1%, respectively. The means of Hb, Hct, MCV, MCH, and MCHC in the anemic group were significantly lower. The positive results for KKU-OF or KKU-DCIP or both were 15.0%, 2.5%, and 1.0%, respectively. The result of positive OF test was a significantly independent factor for anemia. The number of family members was 5 to 7 and more than 7 persons are related factors for anemia in this study. In summary, the contribution of thalassemia and socio-economic factor are associated factors to anemia in this population. These findings should be addressed in public health strategies for the control of anemia of school-aged Muslims in the region.

Evaluation of Hematocrit in Adults with Dengue by a Laboratory Information System

The implementation of a laboratory information system (LIS) at the Hospital for Tropical Diseases in Thailand provides valuable medical resources, particularly for dengue. Hematocrit (Hct), which is often derived from hemoglobin (Hgb), is important in the diagnosis and management of dengue. This study aimed to evaluate the Hct value obtained from the LIS automated analyzer. We prospectively enrolled 163 hospitalized adults with dengue, for whom 1,141 real-time complete blood count (CBC) results were obtained via a hematology analyzer and updated in the LIS database. The median (interquartile range (IQR)) duration of analytic turnaround times (TATs) was 40.0 (30.0–53.0) minutes. Linear regression analysis indicated a significant relationship between Hgb and Hct with a coefficient of determination (Pearson's R²) of 0.92 at red blood cell distribution width (RDW) ≤18, but Pearson's R² decreased to 0.78 at RDW >18. The Hct calculated from the three-fold conversion method and from the analyzer had a Pearson's R² of 0.92. At Hgb <12 g/dl and ≥16 g/dl, a greater difference between the two Hct values was observed, with median (IQR) differences of −0.8% (−1.9%–0.2%) and 0.8% (−0.1%–1.7%), respectively (P value <0.05). In conclusion, the Hgb and Hct of patients with dengue were highly correlated at RDW ≤18. The Hct calculated from the three-fold conversion method and from the analyzer had an excellent relationship, except when the Hgb was <12 g/dl or ≥16 g/dl. Apart from routine CBC evaluation, the LIS could help for accurate data collection in clinical research and development.

Factors associated with anaemia and iron deficiency among women of reproductive age in Northeast Thailand: a cross-sectional study

Background

Anaemia and iron deficiency (ID) affect women of reproductive age globally and considered to be a major public health problem in developing countries. This study determines the prevalence of anaemia and ID among women of reproductive age in urban northeast Thailand and examined the relative contribution of various risk factors to anaemia and ID in this population.

Methods

Three hundred ninety-nine non-pregnant women, aged 18–45 years, from three universities in northeast Thailand participated in this cross-sectional study. Selected socio-demographic, history of blood loss, usual consumption of red meat and tea/coffee, and anthropometric data were collected. Complete blood count including haemoglobin (Hb) concentration, serum ferritin (SF), C-reactive protein (CRP), and thalassemia were determined. Multiple logistic regressions were applied to identify the risk factors of anaemia and ID.

Results

Overall, 370 participants were included for data analyses after excluding women with severe/intermedia thalassemia diseases and/or those with positive serum CRP. The prevalence of anaemia, ID, and iron deficiency anaemia (IDA) were 28.4, 28.4, and 13.2%, respectively. Women with thalassemia had a higher prevalence of anaemia but a lower prevalence of ID than the women without thalassemia. By multiple regression analysis, ID [adjusted OR (AOR) = 4.9, 95% CI = 2.8–8.3], two α-gene defects (AOR = 8.0, 95% CI = 3.0–21.3) and homozygous Hb E (AOR = 8.5, 95% CI = 3.0–24.3) were identified as the potential risk factors of anaemia. Further, the odds of ID were significantly higher among women who donated blood within the past 3 months (AOR = 6.7, 95% CI = 2.8–16.3), and had moderate to a high amount of blood loss during menstruation (AOR = 2.2, 95% CI = 1.3–3.9).

Conclusion

This study found a relatively high but differential prevalence of anaemia and ID among women of reproductive age with or without thalassemia. Only homozygous Hb E and two α-gene defects of thalassemia types and ID were the main factors contributing to anaemia. Recent blood donation, and moderate to a high amount of blood loss during menstruation were potential risk factors of ID in this population.

Nutritional anemia predominant form of anemia in educated young Thai women

OBJECTIVE

Anaemia is one of the most common health problems worldwide, with a high prevalence in Africa and South East Asia, including Thailand. Thai women of childbearing age have an increased risk of anaemia due to several factors including underlying health problems, lifestyles and poor diet. Therefore, we investigated the prevalence of anaemia among female students of Chulalongkorn University (aged 18-22) and categorized causes of the anaemia.

DESIGN

400 Thai female student-volunteers, without known underlying diseases were subjected to blood tests; complete blood count, Haemoglobin typing and serum ferritin level. Bloods, having haemoglobin under 12 g/dl and hematocrit under 36%, were designated as anaemia. Then causes of anaemia are categorized into 3 groups; Iron deficiency, Thalassemia and Others.

RESULTS

We found that 21% of the volunteers were anaemic. In 85 anaemic volunteers, they were classified as Iron deficiency anaemia (IDA); with low serum ferritin levels 42.4%, Thalassemia; total of 6 types 25.9%, IDA and Thalassemia 2.3% and Others 29.4% in which haemoglobin typing and serum ferritin level were normal.

CONCLUSION

Iron deficiency anaemia (IDA) is the major cause of anaemia in Thai female students in our study. Several students were gradually developing anaemia where their haematocrit (Hct) and haemaglobin (Hb) were within reference range but mean corpuscular volume (MCV), mean corpuscular haemaglobin (MCH) and serum ferritin fell below reference range, indicating latent iron deficiency. A few volunteers had both IDA and Thalassemia and also Thalassemia with iron overloaded where health can be deteriorated without knowledge of having these conditions or proper health care. To improve their health, universities or public organizations should provide education and/or screen for anaemia. With the knowledge and understanding of their health issues or underling diseases, students themselves can prevent serious health conditions, improve university performances, and improve their quality of life.

Reticulocyte hemoglobin equivalent in a thalassemia-prevalent area

BACKGROUND

Reticulocyte hemoglobin equivalent (Ret-He), a direct measure of the hemoglobin (Hb) in the young red blood cells, has been reported to be useful in the diagnosis of iron deficiency anemia (IDA) but may have some limitations in thalassemia trait. This study evaluated the differences in Ret-He in school-aged children, and assessed the diagnostic value of Ret-He in identifying IDA in a thalassemia-prevalent area.

METHODS

Blood samples underwent complete blood count analysis, including Ret-He, ferritin, serum iron and total iron binding capacity. Blood samples also underwent Hb typing and a molecular study for α-thalassemia. Receiver operating characteristic analysis was performed to determine the predictive capacity of Ret-He in the diagnosis of IDA. ID was defined as serum ferritin <30 ng/mL and/or transferrin saturation (TSAT) <16%; IDA was defined as serum ferritin <12 ng/mL and/or TSAT <16% with low Hb for age. Normal healthy children (normal controls: NC) had normal iron study, without the thalassemia trait.

RESULTS

Ninety-eight children with a mean age of 12.9 ± 0.6 years were included. Ret-He in the thalassemia trait group (26.7 ± 2.4 pg), ID group (29.0 ± 2.9 pg), IDA group (25.4 ± 2.7 pg), ID + thalassemia trait group (26.6 ± 2.8 pg), and the IDA + thalassemia trait group (24.6 ± 2.3 pg) was significantly lower than in the NC group (30.8 ± 1.7 pg; P < 0.001, 0.01, 0.006, 0.002 and <0.001, respectively). Ret-He had an area under the curve of 0.904 in diagnostic ability for IDA, while a cut-off ≤27 pg had a sensitivity of 91.7% and a specificity of 81%.

CONCLUSION

Ret-He was lowest in subjects with IDA + thalassemia trait. A Ret-He cut-off ≤27 pg was suggestive of IDA in the present study.

Anemia in the Elderly in Northeastern Thailand: A Community-Based Study Investigating Prevalence, Contributing Factors, and Hematologic Features

This community-based study investigated anemia prevalence and certain hematologic features and their possible relationships to thalassemia and iron deficiency (ID) in a population of older people in Northeastern Thailand. Participants included 319 apparently healthy individuals ranging in age from 60 to 98 years, whose current health status was assessed by means of personal interviews. Blood samples were also collected to determine the following parameters: red blood cell indices, serum ferritin, C-reactive protein, hemoglobin profiles, and the α0-thalassemia gene. Based upon established WHO criteria, the overall prevalence of anemia was found to be 47.7%, increasing from 39% within the age group of 60-70 years to 68% in those >80 years. Factors considered to be significant contributors to anemia were classified as ID (3.6%), thalassemia (56.2%), and "unknown" (40.1%). Overall, only 2.4% of participants exhibited any ID. Hematologic changes appear to correlate with age. Our findings provide not only baseline information, potentially useful for implementing appropriate control measures, but also an enhanced awareness and understanding of the factors contributing to anemia among the elderly in the region.

Excessive fluoride consumption increases haematological alteration in subjects with iron deficiency, thalassaemia, and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency

Excessive fluoride consumption leads to accelerated red blood cell death and anaemia. Whether that increases the haematological alteration in subjects with haematological disorders (iron deficiency, thalassaemia, and G-6-PD deficiency) is still unclear. The fluoride in serum and urine and haematological parameters of students at Mae Tuen School (fluoride endemic area) were analysed and compared to those of students at Baan Yang Poa and Baan Mai Schools (control areas). Iron deficiency, thalassaemia, and G-6-PD deficiency were also diagnosed in these students. The students at Mae Tuen School had significantly (P < 0.001) higher levels of mean fluoride in the serum and urine than those in control areas. In both control and fluoride endemic areas, students with haematological disorders had significantly lower levels of Hb, Hct, MCV, MCH, and MCHC than those without haematological disorders. Moreover, the lowest levels of Hb, MCH, and MCHC were observed in the students with haematological disorders who live in the fluoride endemic area. Thus, the excessive fluoride consumption increased haematological alteration in subjects with iron deficiency, thalassaemia, and G-6-PD deficiency and that may increase the risk of anaemia in these subjects.

Testicular function in patients with regular blood transfusion for thalassemia major

Background

Regular blood transfusion and iron chelation therapy have improved the quality of life of patients with thalassemia and increased their longevity, but transfusion also increases the frequency of endocrine complications, possibly because of iron deposition in the pituitary gland or the gonads, or both.

Objective

To evaluate testicular function in patients with thalassemia major by basal hormonal study, and identify risk factors for dysfunction.

Methods

We performed a cross-sectional study of 28 patients with thalassemia major aged 11.7 ± 1.8 (8–14.9) years (15 in prepuberty, 13 in puberty with no delayed puberty) who had regular blood transfusions. A normal control group comprised 64 boys who were matched for age and Tanner genital stage.

Results

The mean level of serum ferritin in the previous year was 1,575 ± 642 ng/mL, and the onset of blood transfusion was at 3.8 ± 2.3 years and iron chelation therapy was 6.6 ± 2.8 years. The trend for anti-Müllerian hormone levels in patients and controls was similar with age, and although higher in the patients, particularly at Tanner stage II, was not significantly different. Testosterone levels were lower in the patients compared with controls; particularly at Tanner stages IV–V (290.88 vs. 537.4 ng/dL, P < 0.05). Serum follicle-stimulating hormone and luteinizing hormone levels were not significantly different between the groups at any Tanner stage.

Conclusion

Patients who received regular blood transfusions had normal Sertoli cell function. Leydig cell dysfunction may occur, even though the patients had a normal pubertal onset.

Red Cell Indices and Formulas Used in Differentiation of β-Thalassemia Trait from Iron Deficiency in Thai Adults

β-Thalassemia (β-thal) and iron deficiency cause most microcytic anemias. Red cell indices and formulas have been established as simple, fast, and inexpensive in discrimination between these two hematological disorders in school children. However, whether these formulas could be applied to diagnose β-thal trait and iron deficiency in adult Thai subjects is unclear. The aim of this study was to examine the diagnostic accuracy of five red cell indices [red blood cell (RBC) counts, mean corpuscular volume (MCV), mean corpuscular hemoglobin (Hb) (MCH), mean corpuscular Hb concentration (MCHC), and red cell distribution width (RDW)] and nine formulas (RDW/RBC, RDW Index, Sirdah, Green and King, Mentzer, England and Fraser, Ehsani, Srivastava and Shine and Lal). Their sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV), efficiency, and Youden's Index were analyzed in 102 β-thal trait and 64 iron deficiency adult Thai subjects. The RDW/RBC formula proved to be the most reliable index as they had 100.0% specificity and PPV and the highest efficiency (94.58%) and Youden's Index (91.18%), as well as high sensitivity (91.18%) and NPV (87.67%). Therefore, this formula could be used in initial discrimination of β-thal trait from iron deficiency in adult Thai subjects.

Red cell indices and formulas used in differentiation of β-thalassemia trait from iron deficiency in Thai school children

Red cell indices and formulas have been established as simple, fast, and inexpensive means for discrimination between the β-thalassemia (β-thal) trait and iron deficiency. However, there were no reports of the diagnostic reliability of different red cell indices and formulas in discrimination of β-thal trait from iron deficiency in the Thai population. The aim of this study was to examine the diagnostic accuracy of five red cell indices [red blood cell (RBC) count, mean corpuscular volume (MCV), mean corpuscular hemoglobin (Hb) (MCH), mean corpuscular Hb concentration (MCHC), and red cell distribution width (RDW)] and eight formulas (Sirdah, Green & King, RDW Index, Menzler, England & Fraser, Ehsani, Srivastava, and Shine & Lal). Their sensitivity, specificity, positive and negative prognostic value and efficiency, were analyzed in 77 Thai school children, 21 with the β-thal trait and 56 with iron deficiency. The Sirdah and Srivastava formulas proved to be the most reliable indexes as they had 100.0% sensitivity and negative predictive value, the highest efficiency (97.4%), and the highest Youden's Index value (96.4%). Therefore, these formulas could be used in initial discrimination of the β-thal trait from iron deficiency in Thai school children.

Interaction of hemoglobin Grey Lynn (Vientiane) with a non-deletional α(+)-thalassemia in an adult Thai proband

Hemoglobin (Hb) Grey Lynn is a Hb variant caused by a substitution of Phe for Leu at position 91 of α1-globin chain, originally described in individual of unknown ethnic background. This article addresses the interaction of Hb Grey Lynn with a non-deletional α⁺-thalassemia found in Thailand, a hitherto un-described condition. The proband was adult Thai woman referred for investigation of mild anemia with Hb 90 g/L. Hb analyses using low pressure liquid chromatography raised a suspicion of abnormal Hb presence, which was failed to demonstrate by cellulose acetate electrophoresis and capillary electrophoresis. DNA sequencing identified a CTT (Leu) to TTT (Phe) mutation at codon 91 corresponding to the Hb Grey Lynn (Vientiane) [α91(FG3)Leu>Phe (α1) on α1-globin gene and a C deletion between codons 36 and 37 on α2-globin gene causing α⁺-thalassemia. As compared to those observed in a compound heterozygote for Hb Grey Lynn / α⁰-thalassemia reported previously, higher MCV (81.7 fL) and MCH (26.3 pg) values with a lower level of Hb Grey Lynn (19.7%) were observed in the proband. The normochromic normocytic anemia observed could be due to the interaction of Hb Grey Lynn with α⁺-thalassemia. The two mutations could be identified using PCR-RFLP and allele-specific PCR assays developed.

Extruded rice grains fortified with zinc, iron, and vitamin A increase zinc status of Thai school children when incorporated into a school lunch program

Iron (Fe), zinc (Zn), and vitamin A (VA) deficiencies are common among children in developing countries and often occur in the same individual. Rice is widely consumed in the developing countries of Asia and the low phytate in polished rice makes it ideal for Zn and Fe fortification. Triple-fortified rice grains with Zn, Fe, and VA were produced using hot extrusion technology. The main objective of the present study was to determine the impact of triple-fortified extruded rice on Zn status in school children in Southern Thailand. Although serum zinc was the main outcome indicator, Fe and VA status were also assessed. School children with low serum zinc (n = 203) were randomized to receive either triple-fortified rice (n = 101) or natural control rice (n = 102) as a component of school lunch meals for 5 mo. Serum Zn, hemoglobin, serum ferritin, serum retinol, and C-reactive protein were measured at baseline and at the end of the study. After the intervention, serum Zn increased (P < 0.05) in both the fortification (11.3 ± 1.3 μmol/L) and control (10.6 ± 1.4 μmol/L) groups, most likely due to the proper implementation of the school lunch and school milk programs, with the increase greater in the group receiving the triple-fortified rice (P < 0.05). Because the children were not Fe or VA deficient at baseline, there was no change in Fe or VA status. We conclude that Zn fortification of extruded rice grains is efficacious and can be used to improve Zn status in school children.

Burden of anemia in relation to thalassemia and iron deficiency among Vietnamese pregnant women

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.

Proxy indicators for identifying iron deficiency among anemic vegetarians in an area prevalent for thalassemia and hemoglobinopathies

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.

Evaluation of the URIT-2900 automated hematology analyzer for screening of thalassemia and hemoglobinopathies in Southeast Asian populations

BACKGROUND

The effectiveness of the URIT-2900 Hematology Analyzer for screening of hemoglobinopathies commonly found in Southeast Asian populations was examined.

METHODS

Appropriate cut-off values of MCV and MCH for screening of α(0) and β thalassemias were derived from the receiver operator characteristic curve conducted initially on 279 subjects with various thalassemia genotypes. Validation was performed additionally in a cohort of another unrelated 313 subjects.

RESULTS

The best cut off values of MCV and MCH were found to be 78fL and 27pg, respectively. Using these cut off values in combination with the dichlorophenolindophenol test in screening of α(0) thalassemia, β thalassemia and Hb E in a cohort study revealed 100% sensitivity, 79.6% specificity, 80.0% positive predictive value and 100% negative predictive value.

CONCLUSION

The combined blood cell counting using the URIT-2900 Automated Hematology Analyzer and dichlorophenolindophenol test is suitable for population screening of thalassemia and hemoglobinopathies in Southeast Asia.