Megaloblastic Anemia: A Drug-Induced Disorder

Megaloblastic anemia is categorized by distinguished hematopoietic cell morphology, unproductive hematopoiesis, induced by folic acid and/or vitamin B12 deficiency [1]. Ineffective DNA synthesis in hematopoietic progenitor cells or myelodysplastic syndrome leading to congenital disorders is commonly responsible for the megaloblastic anemia. In western populations, cobalamin (vitamin B12) deficiency is a common factor to cause the megaloblastic anemia. The complexity of the clinical manifestations of megaloblastic anemia often leads to a misdiagnosis in the geriatric population. Bone marrow aspirate examination and bone marrow core biopsy can aid in the morphologic diagnosis of this disorder. The diagnosis of megaloblastic anemia is quite excellent and uptake of folic acid and/or vitamin B12 with a simple regimen is effective for the treatment [2]. In a case report, a 31year old army soldier with both vitamin B12 and folic acid deficiency in his blood, showed a typical megaloblastic anaemia with oval macrocytes and hypersegmented neutrophils. Three months later, the patient revealed a further reduction in his neutrophil count and a mild thrombocytopaenia. The repeat bone marrow examination exposed a considerable (33%) plasma cell penetratation with erythroid dysplasia and further investigations confirmed a non secretory multiple myeloma (NSMM). The initial presentation was megaloblastic anaemia but the patient was diagnosed with NSMM later [3].