Abstract
Vitamin B12 deficiency is seen in countries like India mainly because of predominantly vegetarian diet and is a significant health problem. Patients present with various neurological and hematological manifestations of megaloblastic anemia. In this case report, we present a 14-year-old girl child having a history of past blood transfusions and iron deficiency anemia currently presenting with severe anemia due to idiopathic autoimmune hemolytic anemia (AIHA) and later found to have concomitant vitamin B12 deficiency. On investigating, she had vitamin B12 deficiency, raised homocysteine and methylmalonic acid levels, positive Direct Coombs Test (DCT), and negative glucose-6-phoshphatase deficiency and osmotic fragility tests. Thyroid profile and tissue transglutaminase IgA (tTg-IgA) tests were negative. Antinuclear antibodies (ANA) and anti-double stranded DNA antibody (anti-dsDNA) serum immunoglobulin were also normal. Bone marrow showed megaloblastic anemia picture. Although AIHA and vitamin B12 deficiency anemia are not common, clinicians should have a high index of suspicion when patients present with hemolytic picture and severe megaloblastic anemia.