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.