What is Folic Acid Deficiency Anemia?
Folic acid deficiency anemia develops as a result of decreased intake of folic acid or malabsorption of the substance in the gastrointestinal tract. Anemia is treated with folic acid by mouth.
Folic deficiency anemia is much less common than B12 deficiency.
Causes of Folic Deficiency Anemia
The cause of folic acid deficiency anemia may be an insufficient content of folic acid in the diet (its main sources are liver and greens), chronic alcohol intoxication, increased need for folic acid (during pregnancy, with malignant tumors, hemolysis, some dermatitis), malabsorption during celiac disease , under the influence of drugs that inhibit (methotrexate, triamteren, anticonvulsants, barbiturates, metmorphine, etc.), increased excretion of folic acid from the body (with liver diseases, hemodialysis).
Pathogenesis during Folic Acid Deficiency Anemia
With a deficiency of cyanocobalamin (its coenzyme – methylcobalamin), folic acid does not convert into its coenzyme form, without which the synthesis of the component that is part of DNA is impossible. As a result, cell division is disrupted and, first of all, actively multiplying cells of the hematopoietic tissue are affected. In the bone marrow, the reproduction and maturation of red blood cells is delayed, their life span is shortened.
Due to impaired blood formation and hemolysis (destruction) of red blood cells, anemia develops, in which cells appear blood cells with pathological signs, and they appear not only in the bone marrow, but also in the blood. The changes relate to leukocytes (leukopenia is noted – a decrease in the number of leukocytes) and thrombocytopenia (a decrease in the number of platelets).
The occurrence of abnormal mitosis and the appearance of giant epithelial cells of the alimentary canal leads to the development of inflammatory processes in the mucous membrane of its departments (stomatitis, esophagitis, gastritis, enteritis). This exacerbates the primary violation of the secretion and absorption of the internal factor and, therefore, increases the deficiency of vitamins (vicious cycle).
As a result of the lack of cyanocobalamin in the body, metabolic products that are toxic to nerve cells accumulate, and fatty acids with a changed structure are synthesized in nerve fibers. Degeneration (gradual qualitative change in cells) of the spinal cord (funicular myelosis) develops, the cranial and peripheral nerves are affected with the development of diverse neurological symptoms.
Symptoms of Folic Deficiency Anemia
The clinical picture of folic acid deficiency anemia has practically no characteristic features – patients are concerned about fatigue, palpitations; upon examination, pale lips, nails, and a bright red tongue are found. Signs of damage to the gastrointestinal tract and nervous system are absent. Examination reveals hyperchromic macrocytic anemia, leukopenia, thrombocytopenia; trial therapy with vitamin B12 does not cause an increase in the number of reticulocytes. If necessary, the diagnosis is confirmed by determining the content of folic acid in serum and red blood cells.
Diagnosis of Folic Deficiency Anemia
Suspicion of folic acid deficiency occurs when hyperchromic (macrocytic) anemia is detected in the hemogram with a normal or low number of reticulocytes in the absence of changes in the number of granulocytes and platelets. The identification of the characteristic picture of megaloblastic hematopoiesis allows with a 50% degree of probability to speak of folic acid deficiency. The decisive diagnostic method is the determination of folic acid in red blood cells. Normally, its content ranges from 100 to 450 ng / l. With folic acid deficiency anemia, the folic acid content in red blood cells decreases.
In the study of peripheral blood – hyperchromic (macrocytic) anemia. Reduced hemoglobin and red blood cells. Other deviations in the hemogram, as a rule, are not noted. An increase in indirect bilirubin is extremely rare.
Treatment of Folic Deficiency Anemia
For the prevention and treatment of folic acid deficiency anemia, folic acid is prescribed at a dose of 1 mg / day orally. If necessary, increase the dose. The number of young blood cells increases after 3-4 days. If neurological symptoms are detected, vitamin B12 should be excluded. With an unrecognized deficiency of this substance, folic acid administration eliminates anemia, but neurological symptoms progress.
Prevention of Folic Deficiency Anemia
Prevention of folic acid deficiency is required by pregnant women, as well as patients taking drugs that can disrupt folic acid metabolism. For the prevention of folic acid deficiency anemia, folic acid preparations are used at a dose of 5 mg / day.