Nutrition Deficiency Anemia

Nutrition Deficiency Anemia

Anemia that occurs due to deficiency of a nutritive substance necessary for erythropoiesis is called nutrition deficiency anemia. The substances which are necessary for erythropoiesis are iron, proteins and vitamins like C, B12 and folic acid. The types of nutrition deficiency anemia are:

Iron deficiency anemia

Iron deficiency anemia is the most common type of anemia. It develops due to inadequate availability of

iron for hemoglobin synthesis. RBCs are microcytic and hypochromic.

Causes of iron deficiency anemia:

i. Loss of blood

ii. Decreased intake of iron

iii. Poor absorption of iron from intestine

iv. Increased demand for iron in conditions like growth and pregnancy.

Features of iron deficiency anemia: Features of iron deficiency anemia are brittle nails, spoonshaped

Nails (koilonychias), brittle hair, atrophy of papilla in tongue and dysphagia (difficulty in swallowing).

Protein deficiency anemia

Due to deficiency of proteins, the synthesis of hemoglobin is reduced. The RBCs are macrocytic and hypochromic. Pernicious anemia or Addison’s anemia Pernicious anemia is the anemia due to deficiency of vitamin B12. It is also called Addison’s anemia. It is due to atrophy of the gastric mucosa because of autoimmune destruction of parietal cells. The gastric atrophy results in decreased production of intrinsic factor and poor absorption of vitamin B12, which is the maturation factor for RBC. RBCs are larger and immature with almost normal or slightly low hemoglobin level. Synthesis of hemoglobin is almost normal in this type of anemia. So, cells are macrocytic and normochromic/hypochromic. Before knowing the cause of this anemia, it was very difficult to treat the patients and the disease was considered to be fatal. So, it was called pernicious anemia. Pernicious anemia is common in old age and it is more common in females than in males. It is associated with other autoimmune diseases like disorders of thyroid gland, Addison’s disease, etc. Characteristic features of this type of anemia are lemon yellow color of skin (due to anemic paleness and mild jaundice) and red sore tongue. Neurological disorders such as

paresthesia (abnormal sensations like numbness, tingling, burning, etc.), progressive weakness and

ataxia (muscular incoordination) are also observed in extreme conditions.

Megaloblastic anemia

Megaloblastic anemia is due to the deficiency of another maturation factor called folic acid. Here, the RBCs are not matured. The DNA synthesis is also defective, so the nucleus remains immature. The RBCs are megaloblastic and hypochromic. Features of pernicious anemia appear in megaloblastic

anemia also. However, neurological disorders may not develop.

4. Aplastic Anemia

Aplastic anemia is due to the disorder of red bone marrow. Red bone marrow is reduced and replaced

by fatty tissues. Bone marrow disorder occurs in the following conditions:

i. Repeated exposure to Xray or gamma ray radiation.

ii. Presence of bacterial toxins, quinine, gold salts, benzene, radium, etc.

iii. Tuberculosis.

iv. Viral infections like hepatitis and HIV infections. In aplastic anemia, the RBCs are normocytic and

normochromic.

5. Anemia of Chronic Diseases

Anemia of chronic diseases is the second common type of anemia (next to iron deficiency anemia). It is characterized by short lifespan of RBCs, caused by disturbance in iron metabolism or resistance to erythropoietin action. Anemia develops after few months of sustained disease. RBCs are normocytic and normochromic. Common causes anemia of chronic diseases:

i. Noninfectious inflammatory diseases such as rheumatoid arthritis (chronic inflammatory autoimmune disorder affecting joints).

ii. Chronic infections like tuberculosis (infection caused by Mycobacterium tuberculosis) and

abscess (collection of pus in the infected tissue) in lungs.

iii. Chronic renal failure, in which the erythropoietin secretion decreases (since erythropoietin is

necessary for the stimulation of bone marrow to produce RBCs, its deficiency causes anemia).

iv. Neoplastic disorders (abnormal and disorganized growth in tissue or organ) such as Hodgkin’s

disease (malignancy involving lymphocytes) and cancer of lung and breast.

RBCs are generally normocytic and normochromic in this type of anemia. However, in progressive disease associated with iron deficiency the cells become microcytic and hypochromic.