**11. Conclusions**

Diagnosis of β-thalassemia and HbE requires laboratory investigations. Screening tests are used to search for carriers, while confirmatory tests are carried out in those samples positive for screening tests with the aim to make the definite diagnosis. There are several pitfalls in these laboratory tests, both in screening tests and confirmatory tests that must not be overlooked, otherwise misdiagnosis will occur.

#### **Acknowledgements**

The author thanks Mr. Eaktong Limveeraprachak of Sawan Pracharak Hospital, Nakorn Sawan Province, Thailand for providing hemoglobin typing results put in this chapter.

**155**

**Author details**

Thanusak Tatu

provided the original work is properly cited.

Division of Clinical Microscopy, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: tthanu@hotmail.com; thanusak.t@cmu.ac.th

*Laboratory Diagnosis of β-Thalassemia and HbE DOI: http://dx.doi.org/10.5772/intechopen.90317*

#### **Conflict of interest**

The authors declare no conflict of interest.

*Laboratory Diagnosis of β-Thalassemia and HbE DOI: http://dx.doi.org/10.5772/intechopen.90317*

*Beta Thalassemia*

βO-thalassemia (β<sup>E</sup>

be done.

occur.

this chapter.

**11. Conclusions**

**Acknowledgements**

**Conflict of interest**

The authors declare no conflict of interest.

ing the hemoglobin typing results.

hemoglobin typing results of the patients. If the patients of β-thalassemia disease (βO/βO) have just received blood transfusion, their hemoglobin types will be A2AF, instead of A2F which is the real hemoglobin type of the βO/βO. If patients of HbE/

blood transfusion should always be taken into account when reading and interpret-

α-thalassemia 1/HbE carrier are lower than those of the single HbE carrier (22.8 ± 4.4% vs. 27.6 ± 3.3%) [84]. Therefore, if HbE carriers have low HbE levels as well as MCV/MCH, further identification of α-thalassemia 1 genotype must

Diagnosis of β-thalassemia and HbE requires laboratory investigations. Screening tests are used to search for carriers, while confirmatory tests are carried out in those samples positive for screening tests with the aim to make the definite diagnosis. There are several pitfalls in these laboratory tests, both in screening tests and confirmatory tests that must not be overlooked, otherwise misdiagnosis will

The author thanks Mr. Eaktong Limveeraprachak of Sawan Pracharak Hospital, Nakorn Sawan Province, Thailand for providing hemoglobin typing results put in

Co-existence of α-thalassemia 1 in β-thalassemia carrier and in HbE carrier can be found some regions. This is called double α-thalassemia 1/β-thalassemia carriers and double α-thalassemia 1 and HbE carriers. Results of one-tube osmotic fragility test are always positive in double α-thalassemia 1/β-thalassemia carriers, being the same as that of the single β-thalassemia carrier. However, MCV/MCH in double α-thalassemia 1/β-thalassemia carriers are slightly higher than those in the single β-thalassemia carriers (70.7 ± 2.6 vs. 68.4 ± 2.7 for MCV, 21.0 ± 1.2 vs. 20.7 ± 0.9 for MCH) [83]. HbA2 level in double α-thalassemia 1/β-thalassemia carriers is lower than that in single β-thalassemia carrier (5.27 ± 0.77% vs. 5.65 ± 0.78%) [29]. In contrast, the results of one-tube osmotic fragility test of double α-thalassemia 1/ HbE carrier are usually positive, being different from those of single HbE which can be either positive or negative. The MCV/MCH in double α-thalassemia 1/ HbE carrier are lower than those of the single HbE carrier (68.7 ± 8.9 fL vs. 75.7 ± 7.5 fL for MCV, 22.5 ± 3.1 pg vs. 24.9 ± 2.8 pg for MCH). HbE level in double

be EFA, instead of EF which is the real hemoglobin type of βO/β<sup>E</sup>

/βO) have recent blood transfusion, their hemoglobin types will

. Therefore, recent

**154**
