Anemias due to nutritional deficiencies are usually macrocytic with low MCV values.
The most common cause of anemia is iron deficiency.
Iron-deficiency anemia can be caused by chronic blood loss, poor dietary intake or absorption, increased demand (pregnancy), or decreased supply (malabsorption).
Megaloblastic anemia is another type of macroyctic anemia that occurs when the body cannot produce enough healthy red blood cells because it lacks vitamin B12 or folate.
Iron-deficiency anemia is characterized by hypochromia (pale red cells) and microcytosis (small RBC size).
The most common cause of anemia is iron-deficiency anemia, which can be caused by poor dietary intake or increased blood loss.
Hemolytic anemias result from premature destruction of RBCs.
Increased red cell destruction occurs when the spleen removes RBCs from circulation faster than they can be replaced.
Hemolytic anemia may result from autoimmune hemolysis, hereditary spherocytosis, sickle cell disease, thalassemia, G6PD deficiency, and other causes.
Thrombocytopenia refers to a decrease in platelet count below normal levels.
Leukopenia refers to a decrease in white blood cell count below normal levels.
Increase in reticulocytes indicates regenerative response to anemia.
Reticulocytosis may occur as part of normal physiologic processes such as during pregnancy or following hemorrhage.
Autoimmune hemolytic anemia is characterized by antibodies against self-antigens on RBC membranes that lead to their premature removal from circulation.
Increased blood loss may occur from menstruation, gastrointestinal bleeding, or other sources.
Anemia due to hemorrhage results from acute bleeding.
Chronic inflammation can also lead to anemia through various mechanisms such as hepcidin production, impaired iron release from macrophages, and reduced erythropoiesis.
Reticulocytosis may also indicate pathological conditions like hemolysis, bone marrow stimulation, or myelodysplasia.
Hepcidin inhibits ferroportin, leading to decreased iron export from enterocytes and macrophages into plasma.
Aplastic anemia is a rare disorder where bone marrow fails to make sufficient numbers of all types of blood cells.
Thrombocytopenia is a condition with low platelet count.