|Year : 2016 | Volume
| Issue : 3 | Page : 310-311
Megaloblastic anemia: The thing that should not be forgotten in diagnosis
Public Health, Hainan Medical University, China; Public Health, Faculty of Medicine, University of Nis, Serbia; Public Health, Joseph Ayobabalola University, Nigeria; Public Health, Surin Rajabhat University, Thailand; Public Health, Dr DY Patil Medical College, Pune, India
|Date of Web Publication||17-May-2016|
Wiwanitkit House, Bangkhae-10160, Bangkok
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Wiwanitkit V. Megaloblastic anemia: The thing that should not be forgotten in diagnosis. Med J DY Patil Univ 2016;9:310-1
"Anemia" is a common problem that can be seen around the world.  This problem is considered as one of the very important nutritional disorders.  There are several types of anemia. Basically, the red blood cell morphology is mainly used for classification of types of anemia. Based on red blood cell shape, anemia can be divided into three main groups:
In the present report, the specific study on megaloblastic anemia, the anemia with abnormal red blood cell is reported.  The classical findings in anemia can be seen. Nevertheless, an important note is "megaloblastic anemia is one of the common causes of undiagnosed anemia." 
- Abnormal small,
- Normal and
- Abnormal large red blood cell.
The interesting consideration is on the diagnosis of megaloblastic anemia. Generally, the diagnosis of anemia requires blood test, complete blood count. In any patients with suspicious signs and symptoms (such as pale conjunctiva), the complete blood count should be performed to estimate hemoglobin (Hb) level. If the abnormal low Hb level is observed, the diagnosis of anemia can be done. For the classification of the type of anemia, the classical peripheral blood smear examination can be useful. However, in the present day, there are many available automated hematology analyzers that can provide red blood cell size parameter, the mean cell volume (MCV). This can be useful for classification of type of anemia due to the red blood cell shape. Using automated hematology analyzer, the megaloblastic anemia can be easily diagnosed based on the two red blood cell parameters, "Hb" and "MCV." Therefore, the problem of underdiagnosis can be decreased in setting where the automated hematology analyzer is available.
However, there are also many issues on diagnosis of megaloblastic anemia. First, the investigation for the rooted cause should be mentioned. , The Vitamin B 12 or folate deficiency is the basic cause of megaloblastic anemia. In the present day, serum Vitamin B 12 and folate can be assessed by special clinical chemistry laboratory. However, this might not be available in the resource limited setting. To get the complete history taking of the patient is needed. The vegetarianism becomes an important risk and the usually forgotten risk is the heavy alcoholic drinking. A so called condition namely "pernicious anemia" should be mentioned. It is a kind of immunological disorder that presents megaloblastic anemia. To diagnose this uncommon condition, it requires "histologically proven atrophic body gastritis, peripheral blood examination showing megaloblastic anemia with hypersegmented neutrophils, cobalamin deficiency and antibodies to intrinsic factor and to gastric parietal cells."  In addition, the infection related megaloblastic anemia should also be mentioned. The fish tape worm infestation is proved to be an important cause of megaloblastic anemia.  This is not a tropical disease, but the disease should also be kept in mind in the present era of globalization.
Finally, the misdiagnosis of megaloblastic anemia should also be mentioned. In fact, the misdiagnosis, especially for false negative, can be common in classical peripheral blood smear examination. Nevertheless, with the use of high-tech automated hematology analyzer, the problem can still be seen. It is acknowledged that "inaccuracies in the measured MCV of dehydrated or otherwise undeformable cells" can be possible, and this can lead to erroneous MCV report. 
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