Hunt for the Hidden TraitSource of Support: Nil
Objective: To assess the efficacy of a peripheral smear examination as a screening tool for β-thalassemia trait.
Materials and Methods: 17 623 Leishman-stained peripheral smears were evaluated during the period from July 2006 to September 2007. The following parameters were studied: hemoglobin, red blood cell count, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and red cell distribution width. All the cases that showed microcytosis, hypochromia, erythrocytosis and absence of anisopoikilocytosis were suspected of having the thalassemia trait (TT), and all these cases were further evaluated with Alkaline Hemoglobin Electrophoresis for confirmation.
Results: Of the 17 623 smears examined, 60 cases were considered suspicious of having TT. Alkaline hemoglobin electrophoresis carried out on all these cases revealed an elevated HbA 2 (Mean = 7.5%). Five cases evaluated were found to have other hemoglobinopathies (1 Sickle cell trait, 3 Hb-E, 1 thalassemia intermedia).
Conclusion: Careful screening of peripheral smear is an invaluable screening tool for thalassemia trait (PPV - 95%). There must be awareness among the peripheral centers about the importance of peripheral smear screening and the affected persons should be counseled.
29 January 2020 (online)
Thieme Medical and Scientific Publishers Private Ltd.
A-12, Second Floor, Sector -2, NOIDA -201301, India
- 1 Lukens JN. The thalassemias and related disorders: Quantitative disorders of hemoglobin synthesis. In: Lee GR, Bithell TC, et al, editors. Wintrobe′s Clinical hematology, 9th ed. Philadelphia: Lea and Febiger; 1993. p. 1102-45.
- 2 Maheshwari M, Arora S, Kabra M,. Menon PS. Carrier screening and prenatal diagnosis of β Thalassemia. Indian Pediatr 1999;36:1119-25.
- 3 Weatherall DJ. The thalassemia. In: Beutler E, Lichtman MA, et al, editors. Willams Hematology, 6th ed. New York; McGraw Hill; 2001. p. 547-80.
- 4 Kotwal J, Saxena R, Choudhry VP, Dwivedi SN, Bhargava M. Erythrocyte indices for discriminating thalassaemic and non-thalassaemic microcytosis in Indians. Natl Med J India 1999;12:266-7.
- 5 d′Onofrio G, Zini G, Ricerca BM, Mancini S, Mango G. Automated measurement of red blood cell microcytosis and hypochromia in iron deficiency and beta-thalassaemia trait. Arch Pathol Lab Med 1992;116:84-9.
- 6 Bentley SA, Ayuscue LH, Watson JM, Ross DW. The clinical utility of discrimant functions for the differential diagnosis of microcytic anemias. Blood 1989;15:575-82.
- 7 Afroz M, Shamsi TS, Syed S. Predictive value of MCV/RBC count ratio to discriminate between iron deficiency anaemia and beta thalassaemia trait. J Pak Med Assoc 1998;48:18-9.
- 8 Eldibany MM Totonchi KF, Josepj AJ. Usefulness of certain red blood cell indices in diagnosing and differentiating thalassaemia trait from iron deficiency anemia. Am J Clin Pathol 1999;111:676-82.