Prevalence of alpha thalassemia in microcytic anemia: a tertiary care experience from north India

Twelve Cases of Hb Manitoba [α102(G9)Ser→Arg]: the Fluctuation in the Variant Expression

Hb Manitoba [α102(G9)Ser→Arg] is a rare α chain variant with diverse ethnic origins. It is mildly unstable with an expression of around 10.0-14.2% in the heterozygous state in most literature. In this study, 12 cases of Hb Manitoba [11 cases carried Hb Manitoba II (HBA1: c.309C>A) and one case carried Hb Manitoba IV (HBA1: c.307A>C)] were detected during a wide-spectrum study of α chain variants in the UK. Fluctuation in variant expression from 6.9 to 15.2% of total Hb on high performance liquid chromatography (HPLC) would pose a diagnostic dilemma in routine laboratories. Focusing on the variant expression, the median of Hb Manitoba was around 11.5% of total Hb in three cases, apparently with normal hemoglobin (Hb), and normal red blood cell (RBC) indices. Two cases showed a higher expression (13.9 and 15.2%) and five cases showed a lower expression (6.9-9.9%). The common α-thalassemia (α-thal) -α^3.7 (rightward) deletion coexisted with one case of increased Hb Manitoba expression. Iron (or other nutrient) deficiency was likely the cause of decreased Hb Manitoba percentage in this study. The α73(EF2)Val→Val (α2) (HBA2: c.222G>T) polymorphism is published for the first time and coexisted with two cases. The Cap +14 (C>G) (HBA2: c.-24C>G) polymorphism coexisted with another case in a heterozygous state. In conclusion, the fluctuation in variant expression can cause a diagnostic dilemma, especially in routine laboratories. Screening for the common -α^3.7 deletion and iron deficiency is recommended when an α chain variant is suspected.

Deletional Alpha-Thalassemia Alleles in Amazon Blood Donors

Alpha-thalassemia is highly prevalent in the plural society of Brazil and is a public health problem. There is limited knowledge on its accurate frequency and distribution in the Amazon region. Knowing the frequency of thalassemia and the prevalence of responsible mutations is, therefore, an important step in the understanding and control program. Hematological and molecular data, in addition to serum iron and serum ferritin, from 989 unrelated first-time blood donors from Amazonas Hemotherapy and Hematology Foundation (FHEMOAM) were collected. In this study, the subjects were screened for -α ^3.7/4.2/^20.5, -^SEA, -^FIL, and -^MED deletions. Alpha-thalassemia screening was carried out between 2016 and 2017 among 714 (72.1%) male and 275 (27.9%) female donors. The aims of this analysis were to describe the distribution of various alpha-thalassemia alleles by gender, along with their genotypic interactions, and to illustrate the hematological changes associated with each phenotype. Amongst the patients, 5.35% (n = 53) were diagnosed with deletion -α ^-3.7 and only one donor with α ^-4.2 deletion. From the individuals with -α ^-3.7, 85.8% (n = 46) were heterozygous and 14.20% (n = 7) were homozygous. The frequency of the -α ^-3.7 deletion was higher in male (5.89%) than in female (4.0%). There is no significant difference in the distribution of -α ^-3.7 by gender (p = 0.217). The -α ^20.5, -^SEA, and -^MED deletions were not found. All subjects were analyzed for serum iron and serum ferritin, with 1.04% being iron deficient (n = 5) and none with very high levels of stored iron (>220 µg/dL). Alpha-thalassemia-2^3.7kb deletion was the most common allele detected in Manaus blood donors, which is a consistent result, once it is the most common type of α-thalassemia found throughout the world. As expected, the mean of hematological data was significantly lower in alpha-thalassemia carriers (p < 0.001), mainly homozygous genotype. Leukocytes and platelet count did not differ significantly. Due to the small number of individuals with iron deficiency found among blood donors, the differential diagnosis between the two types of anemia was not possible, even because minor changes were found among hematological parameters with iron deficiency and α-thalassemia. Despite this, the study showed the values of hematological parameters, especially MCV and MCH, are lower in donors with iron deficiency, especially when associated with α-thalassemia, and therefore, it may be useful to discriminate different types of microcytic anaemia. In conclusion, we believed screening for thalassemia trait should be included as part of a standard blood testing before blood donation. It should be noted that this was the first study to perform the screening for alpha deletions in blood donors from the Manaus region, and further studies are required to look at the effects of donated thalassemic blood.

Prevalence of 3.7 and 4.2 deletions in Sudanese patients with red cells hypochromia and microcytosis

Objective

Alpha-thalassemia is a genetic disorder characterized by deletions of one or more α globin genes that result in deficient of α globin chains reducing haemoglobin concentration. The study aimed to screen 97 patients with microcytosis and hypochromasia for the 3.7 and 4.2 alpha thalassemia deletion mutations.

Results

Out of 97 patients screened, only 7 were carriers for the 3.7 deletion and all patients were negative for the 4.2 deletion. The 3.7 deletion was found in Foor, Hawsa and Rezagat Sudanese tribes. In the carriers of the 3.7 deletion, Red Blood Cells and Haematocrit were significantly increased. The Red Blood Cells were 7.23 ± 0.78 × 10¹²/L in adult males and 7.21 ± 0.67 × 10¹²/L in adult females while in children were 5.07 ± 0.87 × 10¹²/L. The mean cell volume and mean cell haemoglobin were significantly decreased, but the mean cell haemoglobin concentration slightly decreased. Haemoglobin levels didn’t revealed statistically significant decrease in adult males (11.7 ± 0.57 g/dL) and adult females (11.25 ± 0.64 g/dL), while in children were (11.6 ± 2.95 g/dL). Haemoglobin electrophoresis revealed two patients of the 3.7 and 4.2 negative were carriers for β-thalassemia. The study concluded that α^3.7 deletion has frequency of 0.07 in Sudanese with hypochromasia and microcytosis.

Undiagnosed Hemoglobinopathies: A potential threat to the premarital screening program

Objectives

To evaluate the prevalence of undiagnosed hemoglobinopathies among individuals visiting the premarital screening Centre.

Methods

This study was conducted at Premarital Screening Centre, King Fahad Central Hospital and Research Centre, Jazan, between January 2018 and October 2018. A total of 3,970 (male n =1,859 and female n = 2,111) individuals were included in the study. Data of complete blood count, hemoglobin electrophoresis and sickling tests of all individuals recruited in the study were obtained and statistically analyzed.

Results

One thousand three hundred and twelve individuals had abnormal complete blood counts or hemoglobin electrophoresis results, that include sickle cell trait (13.5%), sickle cell disease (0.7%), β thalassemia with sickle cell trait (2.46%), β thalassemia trait (1.51%), β thalassemia major (0.075%), suspected α thalassemia or other hemoglobinopathies (4.43%), hemoglobin H (0.3%), hemoglobin E (0.075%), undiagnosed cases (0.91%) and iron deficient (7.23%).

Conclusion

A high percentage of individuals are suspected for α thalassemia or other hemoglobinopathies that needs to be diagnosed. Further investigations shall be included in the premarital screening program to diagnose these inconclusive cases. Coexistence iron deficiency with thalassemia shall also be ruled out during premarital screening program.

Causes of microcytic anaemia and evaluation of conventional laboratory parameters in the differentiation of erythrocytic microcytosis in blood donors candidates

CONTEXT AND OBJECTIVE

Microcytic anaemia results from defective synthesis of haemoglobin in the erythroid precursors, causing a reduction in its mean corpuscular volume (MCV). The most common causes of microcytosis, without the increase in HbA₂ levels, are iron deficiency anaemia (IDA) and α-thalassemia. The aim of this study was to identify the causes of microcytic anaemia and evaluate the haematological parameters from blood donors deemed ineligible (due to the low haematocrit level) that would differentiate the IDA and α-thal, whether isolated or in association.

METHODS

Genomic DNA was submitted to the polymerase chain reaction multiplex for the diagnosis of the most common allele deletions of α-thal and erythrogram and in order to verify haematological parameters. Iron deficiency (ID) was determined through the measurement of serum ferritin.

RESULTS

Of the 204 samples, 82 (40.2%) were identified with ID, 24 (17.8%) with α-thal and 10 (4.9%) with ID associated with α-thal. In the α-thal with ID group haemoglobin (Hb), MCV, mean corpuscular Hb concentration (MCHC) and mean corpuscular Hb (MCH) values were significantly lower compared to the isolated α-thal. In the group with ID Hb, MCV, MCHC and MCH values were significantly lower compared to those with isolated α-thal. The α-thal with ID group, showed Hb, MCV, MCHC and MCH significantly reduced when compared to those with IDA.

CONCLUSIONS

This study showed that the values of haematological parameters, especially haematocrit, Hb, MCV, MCH, MCHC and red blood cell distribution width (RDW), are lower in patients with IDA, especially when associated with α-thal and therefore it may be useful to discriminate between the different types of microcytic anaemia.

Inherited haemochromatosis with C282Y mutation in a patient with alpha-thalassaemia: a treatment dilemma

A Caucasian 24-year-old female patient suffers from two hereditary disorders: alpha-thalassaemia, which is prevalent in Asia and rare in Europe, and haemochromatosis, which is prevalent among northern Europe and rare in Asia. The clinical presentation and management of one of these diseases is controversial for the other. She presented 5 years ago with a clinical picture of refractory iron-deficiency anaemia secondary to menorrhagia. On treating her with the standard iron therapy, her anaemia persists although with adquate iron stores. This prompted further investigations that revealed in addition to hereditary haemochromatosis, alpha-thalassaemia because of abnormal blood indices. The treatment of thalassaemia with either iron or blood transfusion is not advisable in haemochromatosis, while standard treatment of haemochromatosis with venesection will worsen the anaemia. As iron chelating agents were not approved in Australia for haemochromatosis, haematinics support was commenced with a satisfactory improvement of anaemia thus allowing for further venesection.

Iron deficiency anemia interfering the diagnosis of compound heterozygosity for Hb constant spring and Hb Paksé: The first case report

BACKGROUND

Diagnosis of thalassemia or hemoglobinopathy concomitant with iron deficiency anemia (IDA) is challenging.

METHOD

We report a case of 43-year-old female whose diagnosis of compound heterozygosity for hemoglobin Constant Spring (HbCS) and Hb Paksé became apparent after the treatment of IDA.

RESULTS

Prior to treatment, Hb analysis using isoelectric focusing (IEF) showed HbA 95.6%, HbA₂ 2.7%, and HbCS 1.7% compatible with heterozygous HbCS. After 4 months of oral iron therapy resulting in an improved Hb level, her HbCS level was substantially increased to 8.7% on IEF suggesting homozygous HbCS. Subsequent DNA analysis using multiplex amplification refractory mutation system analysis revealed compound heterozygosity for HbCS and Hb Paksé.

CONCLUSION

This case demonstrated that IDA can significantly reduce HbCS/Hb Paksé levels and probably mask the diagnosis of homozygous HbCS, homozygous Hb Paksé or the compound heterozygosity for both hemoglobinopathies by hemoblogin analysis. The test should be repeated after resolution of IDA, or molecular testing should be performed to confirm the diagnosis.

Knowledge, Attitude and Practice of Carrier Thalassemia Marriage Volunteer in Prevention of Major Thalassemia

Introduction:

Thalassemia is the most common genetic disorder and rising in the world as a health problem. Due to the criticality of this disease, in our country thalassemia prevention programs are more importance. The aim of this study was investigation of knowledge, attitude and behavior of marrying partners who were thalassemia genetic carriers in prevention of the birth of the children with major thalassemia

Methods:

This study was a descriptive-analytic study. Data collection tool was a self-administered questionnaire that included 43 items. The content validity of questionnaire was investigated under the supervision of physicians, experts of health education and promotion. Its reliability was confirmed by Cronbach’s Alpha test. The subjects in the study consisted of 100 marrying partners who were genetic carriers of thalassemia who referred to Premarital Counseling Center in Iranshahr City. Iranshahr is a a large city of Sistan and Balouchestan Province that located in southeast of Iran. The subjects were selected by convenience non-probability sampling method. Data analyzed using descriptive and analytic statistical tests in SPSS 16.00 and level of significance considered on α < 0.05.

Findings:

The average age of men and women that participated in this study was 21.92 and 24 years respectively. 88% of the partners had familial relationships. The educational level of most of the men (34%) was diploma and of women (44%) was pre-diploma. The research findings showed that 7% and 62% of the subjects had poor and mediocre levels of knowledge respectively. Also results showed that only 13% of them had a satisfactory behavior and educational status had a positive correlation with knowledge, behavior, perceived susceptibility and perceived severity (P<0.05). As well there was a significant statistical relationship between gender and familial relationship, and the perceived barriers of participants. (p=0.01).

The survey viewpoint of participants showed that they believed knowledge increasing (40%), genetic counseling (33%) and premarital screening (27%) were the most important strategies for prevention of thalassemia.

Conclusion:

The perceived barriers were the strongest predictors for preventive behaviors of incidence of major thalassemia in marrying partners, therefor educational interventions should focused on perceived barriers removing in Volunteer marrying partners.