Can leukopenia and thrombocytopenia occur due to B12 or folate deficiency?

Leukopenia and thrombocytopenia can indeed occur due to both vitamin B12 and folate deficiencies. These deficiencies disrupt the normal production of blood cells in the bone marrow, leading to a decrease in the number of white blood cells (leukopenia) and platelets (thrombocytopenia).

Vitamin B12 and folate are both essential for DNA synthesis and cell division. Without sufficient levels of these vitamins, hematopoietic (blood-forming) stem cells cannot proliferate and differentiate effectively, resulting in lower counts of red blood cells, white blood cells, and platelets. This can lead to megaloblastic anemia, where there are large, immature, and dysfunctional cells in the bone marrow.

Both deficiencies can result in the full spectrum of hematological manifestations, making it important to consider both when evaluating a patient presenting with these lab findings. This understanding is critical in clinical practice, as addressing the underlying vitamin deficiency can restore normal blood cell production over time.