Clinico-haematological profile of children with vitamin B12 deficiency anaemia

Background: In India, megaloblastic anaemia due to vitamin B12 deficiency is a major cause of nutritional anaemia in children. Objectives: To assess the magnitude and study the clinical profile of megaloblastic anaemia due to vitamin B12 deficiency in the age group 3 months to 12 years. Setting and design: This was an observational study carried out in Mahatma Gandhi Institute of Medical Sciences, Sewagram, Central India, from December 2015 to June 2017. Method: All children visiting the hospital OPD or admitted in wards during the study period were screened for anaemia and those having haemoglobin <11g/dl (children <6 years) or <12g/dl (6-12 years) were included in the study. Total 110 children were included in study and their clinical and haematological profile was studied. Statistical analysis software used was SPSS 22.0 version and Graph Pad Prism 6.0 version. Results: Out of 110 anaemic children, 22 had megaloblastic anaemia with vitamin B12 levels below 200ng/L and incidence was maximum in the age group of 6 to 12 months. Most common symptom was pallor followed by loss of appetite _________________________________________ Associate Professor, Department of Paediatrics, Mahatma Gandhi Institute of Medical Sciences (MGIMS), Sewagram, India, Associate Professor, Department of Pediatrics, Jawaharlal Nehru Medical College, Datta Meghe Institute of Medical Sciences, India, DNB Family Medicine, MGIMS, Sewagram, India *Correspondence: richa6101@gmail.com orcid.org/ 0000-0003-0729-5887 (Received on 17 December 2019: Accepted after revision on 24 January 2020) The authors declare that there are no conflicts of interest This study was funded by the MGIMS research scientific committee Open Access Article published under the Creative Commons Attribution CC-BY License and fatigue. On peripheral smear examination, 14 patients (63.6%) had macrocytosis and hypersegmented polymorphs and 4 patients (18.2%) had pancytopenia. Conclusions: Out of 110 anaemic children 20% had megaloblastic anaemia with vitamin B12 levels below 200ng/L. More than 75% of megaloblastic anaemia due to B12 deficiency occurred in the 6 months to 6 years age group. On peripheral smear, 64% had macrocytosis and hypersegmented polymorphs and 18% had pancytopenia. DOI: http://dx.doi.org/10.4038/sljch.v49i4.9261 (

Conclusions: Out of 110 anaemic children 20% had megaloblastic anaemia with vitamin B12 levels below 200ng/L. More than 75% of megaloblastic anaemia due to B12 deficiency occurred in the 6 months to 6 years age group. On peripheral smear, 64% had macrocytosis and hypersegmented polymorphs and 18% had pancytopenia.

Introduction
In India, 60-70% of children under the age of 6 years have varying degrees of anaemia 1 . According to available studies in India, 65% infants, 60% 1-6 year olds, and 88% adolescent girls are anaemic 2 . In children, most anaemia is nutritional with megaloblastic anaemia a major contributory factor. Earlier, folate deficiency was a major cause of megaloblastic anaemia in comparison to vitamin B12 deficiency. However, during the past few years, prevalence of folic acid deficiency has decreased from 70-75% to 2-10% 3-5 . Today, vitamin B12 deficiency is a significant cause of megaloblastic anaemia.

Objectives
Current study was undertaken to assess the magnitude and to study clinical profile of megaloblastic anaemia due to vitamin B12 deficiency in the age group 3 months to 12 years. All children in the age group of 3 months to 12 years, admitted as well as attending out-door facility, at Kasturba hospital were screened for anaemia by haemoglobin (Hb) concentration assessment. Those having Hb concentration less than 11g/dl (children less than 6 years) and 12g/dl (children between 6-12 years) were included in study after taking written informed consent from the parents. Their clinical and haematological features were observed and subjected to investigation (vitamin B 12 level). The normal reference range of serum vitamin B12 is above 300ng/L. The range between 200 to 300 ng/L is borderline. Hence the levels less than 200 were considered as low and as diagnostic of megaloblastic anaemia. Children who had received blood transfusion in the last 6 months and children whose peripheral smear showed the picture of thalassaemia, sickle cell anaemia, or some alternative diagnosis were excluded from the study.

Method
Sample size was estimated using Open EPI software, by using formula of cross-sectional prevalence study for 95% confidence interval and a desired absolute precision of 6% with following assumptions: P=50% (assuming that 50% of women will have adequate health literacy so as to get the maximum possible sample size) Nonresponse rate of 20%. The sample size came out to be 110.
Statistical analysis used descriptive and inferential statistics using Chi square test, student's unpaired t-test and Pearson's correlation coefficient.
Software used in the analysis were SPSS 22.0 version and Graph Pad Prism 6.0 version. A pvalue less than 0.05 was considered significant.

Results
The prevalence of megaloblastic anaemia is shown in Table 1. Age wise prevalence of megaloblastic anaemia with mean Vitamin B12 levels is shown in Table 2.
Prevalence of megaloblastic anaemia was maximum in the 6 to 12 month age group with mean vitamin B12 level 119.5ng/L. The relationship of age with megaloblastic anaemia was significant with a p value of 0.015.  Mean corpuscular volume (MCV) of patients with megaloblastic anaemia is shown in Table 4. Mean MCV of megaloblastic children in age group 6 to 12 month was 116.9fL. The relationship of MCV with megaloblastic anaemia was significant with a p value 0.047. The clinical profile of patients with megaloblastic anaemia is shown in Table 5.  . It is thought that as the anaemia becomes more severe, thrombocytopenia develops followed by neutropenia. Further, 27% patients had fever which resulted in leucocytosis which ultimately decreases the degree of pancytopenia. In our study hypersegmented polymorphs were observed in about 63.6% patients; however, another series reported the occurrence of hypersegmented polymorphs to be 43%. This disparity in clinicohaematological features of megaloblastic anaemia results because of difference in duration of onset of anaemia, socio-economical condition of patients, nutrition of patients, and coexisting illness.

Conclusions
Out of 110 anaemic children 20% had megaloblastic anaemia with vitamin B12 levels below 200ng/L. More than 75% of megaloblastic anaemia due to B12 deficiency occurred in the 6 month to 6 year age group. On peripheral smear, 64% had macrocytosis and hypersegmented polymorphs and 18% had pancytopenia.