European Journal of Cardiovascular Medicine

Macrocytosis is common in various clinical settings and it is found in approximately1.7–3.6% of people admitted forcare for any cause^1-3. Macrocytosis would be seen even in the absence of anemia. Heterogeneous group of disorders acting via various known and unknown processes can lead to macrocytic anemia. Macrocytic anemia can be classified in two pathogenic group.^4-5

1. Non Megaloblastic Macrocytic Anemia (NMMA)- it is results from increased lipid deposition on red cell membrane, mainly in liver disease.
2. Megaloblastic Anemia (MA)- due to vitamin b12 deficiency /folate deficiency and in myelodysplastic syndromes.^6-7

The automated reticulocyte count measurements increases the precision and accuracy compared with traditional manual counts.^8,9 The reticulocyte maturity can assessed, based on the staining intensity of reticulocytes, which is proportional to their RNA content^10,11.

In this study, we tested the use of reticulocyte maturation parameters in the screening of macrocytic anemia patients, to distinguish causes associated with ineffective erythropoiesis (MDS and MA) and NMMA .We describe significant differences in immature reticulocyte fraction (IRF),absolute reticulocyte count(ARC)

and mean reticulocyte volume (MRV) values between NMMA and macrocytic anemia due to MDS. These differences were sufficiently clear to provide a reliable screening diagnosis.¹²

MDS generally display macrocytosis and dyserythropoiesis in a variety of structural abnormalities affecting metabolism, hemoglobin and membrane antigens or even the presence of abnormal mitochondrial deposits^13,14.  

We have conducted this study in the department of pathology. A two year prospective study was done and a total of 100 blood samples were examined among them 50 samples were control and 50 cases.

The necessary data was collected from patients and their records. Complete information regarding alcohol intake, drug intake, thyroid disorder and other comorbid illness was obtained.

All the samples were processed on 5 part hematology analyzer.

All routine hematological and reticulocyte maturation parameters were extracted in 50 cases of macrocytic anemia, which includes estimating

• hemoglobin level,
• red blood cell indices (MCV, MCH, MCHC),
• red cell distribution width (RDW),
• total leucocyte count,
• differential leucocyte count, platelet count,
• reticulocyte count, and
• examination of peripheral smear.

If the patients showed the features of megaloblastosis like occurrence of hypersegmented neutrophils or macro ovalocytes then bone marrow aspiration and biopsy will be carried out after obtaining the consent. Patients fasting vitamin B12 and folic acid were measured.

Automated reticulocyte analysis :  Reticulocyte maturation analysis was performed using five part analyser . This instrument provides the following parameters: absolute reticulocyte count (ARC) percentage, corrected reticulocyte counts (CRC), percentages of maturation fractions according to three classes: low RNA content (RETL), medium RNA content (RETM) and high RNA content (RETH). It also determines: mean reticulocyte volume (MRV), and immature reticulocyte fraction (IRF).

Inclusion criteria: Alladultpatientwithmacrocyticanemia(MCV>100fl).

Exclusion criteria:Immunehemolyticanemia , Afterbloodloss ,Certain drug(like, methotrexate,    Phenytoin,Antiretroviralagentsetc),Bloodtransfusion(within30days),Pregnantwoman.

LIMITATION OF STUDY : This study can be only used as screening test to differentiate between various causes of macrocytic anemia. It is not a diagnostic test. The instrument (5 part hematology analyser) is not available at all places and  also not cost effective.

A total of 100 samples (cases -50, controls -50)  were  studied. In our study  we took 50  blood samples of cases in which 05 MDS patients ,13 patients with NMMA and 25 patients with MA while 07 DM patients. Out of 13 NMMA patients 09 males and 04 females, out of 05 MDS pt. 04 males  and 01 females and in MA 15 males and 10 females. 50 peripheral blood samples were obtained from healthy donar as control.

Table 1: Age wise distribution of cases of Macrocytic Anemia along with control

2. Distribution of cases of macrocytic anemia as per sex along

with controls

3.Distribution of cases of Macrocytic Anemia according to

Reticulocyte Count

  4: Distribution of cases in macrocytic anemia according to

Mean Reticulocyte volume(MRV)

5. Distribution of cases in macrocytic anemia according to

Immature Reticulocyte Fraction

The most common age group affected by macrocytic anemia  is middle age (30-40 yrs) group.This  study agrees with the result of ‘ A Torres Gomez et al, who also suggest that age were independently  associated with macrocytic anemia. In our study males are affected more commonly than females with M:F ratio of 2:1 and agrees with A Torres Gomez et al. In our study hemoglobin in control group ranged from 10.5-15.9 g/dl with mean value 12.7  1.6 and in cases group ranged from 2.3-10.8   with mean value 7.77  2.31.In our study most cases showed moderate to severe degree of anemia. In this study MA having red blood cells showed high mean cell volume than NMMA and  it was  statistical significant (p < 0.05). These findings are similar to result of ‘A Torres Gomez et al.

In our study mean corpuscular volume (MCV) in case group ranged from 100.3-128.1fl with mean value 113.2 8.2 and in control groups ranged from  80.1- 97.3 fl with mean value 83.1 5.7 . In this study MA having red blood cells showed high mean cell volume than NMMA and  it was  statistical significant              

In conclusion , the differential diagnosis of macrocytic Anemia  is a great challenge to clinicians but with the help of maturation parameters ,this can be made easy. The main advantage of maturation parameters in macrocytic  anemia is to find out the spectrum of macrocytic anemia and  establish the role of reticulocyte maturation parameters in NMMA and MA. It is used as a screening test in macrocytic anemia.We observed in our study that released reticulocytes showed more immature appearance with high MRV and high IRF in MA than NMMA.

       In conclusion it is crucial to differentiate  between MA and NMMA. For  definitive diagnosis of MDS we eventually requires bone marrow aspiration and cytogenetic studies. The biochemical analysis iron status , serum cobalamine and folate levels are normal  along with increased value of IRF and MRV which  makes diagnosis of  macrocytic anemia.

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 3.Christine A. Moore; Abdullah Adil.et al 2022: evaluation of megaloblastic and non megaloblastic anemia.

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