What type of blood cells are affected in pernicious anemia?

In pernicious anemia, the primary issue involves the production of red blood cells, specifically relating to the formation of megaloblasts. This condition is caused by a deficiency in vitamin B12, which is essential for proper red blood cell maturation. Without adequate vitamin B12, the bone marrow produces abnormal, large, immature red blood cells called megaloblasts, which cannot develop into healthy red blood cells.

Individuals with pernicious anemia may experience symptoms associated with ineffective red blood cell production, such as fatigue, weakness, and pale skin. The megaloblasts have a characteristic appearance in the bone marrow, indicating that the erythropoiesis (the process of producing red blood cells) is disrupted.

While white blood cells, platelets, and thrombocytes may be present in varying levels, the hallmark characteristic of pernicious anemia specifically relates to the presence and nature of megaloblasts in the red blood cell development pathway. This makes megaloblasts the correct answer when identifying the type of blood cells affected in this condition.