Parenteral vs Oral Vitamin B12 in Children With Nutritional Macrocytic Anemia: A Randomized Controlled Trial

ABSTRACT

Background: There is limited literature in children on efficacy of different routes of vitamin B12 administration for vitamin B12 deficiency macrocytic-megaloblastic anemia. Objective: To compare parenteral with oral vitamin B12 therapy in children with macrocytic-megaloblastic anemia. Study design: Single-center, open-label randomized controlled trial. Participant 80 children aged 2 month-18 year with clinical and laboratory features of nutritional macrocytic anemia. Intervention All children received an initial single parenteral dose of 1000 µg vitamin B12 followed by randomization to either parenteral or oral vitamin B12 for subsequent doses. Group A was given 1000 µg intramuscular (IM) vitamin B12 (3 doses on alternate days for those aged <10 year, five doses for age >10 year), followed by monthly 1000 µg IM for the subsequent two doses. Group B was given daily oral vitamin B12 1500 µg (500 µg in <2 years age) for three months. Folic acid and iron supplementation, and relevant dietary advice were given to both groups in a similar fashion. Outcome: Improvement in serum vitamin B12 levels and total hemoglobin was compared three months post-treatment. Result: The median(IQR) increase in serum vitamin B12 level was significantly higher in group A [600 (389,775) vs 399 (313, 606) pg/mL; P= 0.016]. The median (IQR) rise of hemoglobin was also more in group A [2.7 (0.4,4.6) vs 0.5 (-0.1,1.2) g/dL; P=0.001]. Conclusion: Increase in serum vitamin B12 levels and hemoglobin was better in children with nutritional macrocytic anemia receiving parenteral as compared to oral vitamin B12.