Anemia

ANEMIA – Etiology, Classification, Clinical Manifestations and Management

Anemia is a reduction in red blood cells (erythrocytes) which in turn decreases the oxygen carrying capacity of the blood. Anemia reflects on abnormality in RBC number, structure and function.

ETIOLOGY

• Loss of RBC’s: Occurs with bleeding, potentially from a major source, such as the gastrointestinal tract, the uterus, the nose, or a wound.
• Decreased production of RBC’s: Can be caused by a deficiency in cofactors (including folic acid, vitamin B12 and iron) required for erythropoiesis, RBC production may also be reduced if the bone marrow is suppressed (e.g. by tumor, medication, toxin) or is in adequately stimulated because of a lack of erythropoietin (as occur in chronic renal disease).
• Increased destruction of RCB’s: May occur because of an overactive RES(reticuloendothelial system) or because the bone marrow produces abnormal RCB’s that are then destroyed by the RES (sickle cell anemia)

CLASSIFICATION OF ANEMIA

• Morphologic
• Etiologic

Morphologic Classification:

• Normocytic, normochromic
• Macrocytic, normochromic
• Microcytic, hypochromic

Etiological Classification:

Decreased erythrocyte production (hypoproliferative anemia)

• Decreased hemoglobin production
  • Iron Deficiency
  • Thalassemias
• Defective DNA synthesis
  • Cobalamin deficiency
  • Folic acid deficiency
• Decreased number of erythrocyte precursors
  • Aplastic anemia
  • Chronic diseases
  • Chemotherapy
• Blood loss
  • Acute : Trauma, blood vessel  rupture
  • Chronic: Gastritis, menstrual flow, hemorrhoids

Increased erythrocyte destruction (hemolytic anemia)

• Intrinsic: Abnormal hemoglobin (sickle cell anemia), enzyme deficiency (G-6-PD)
• Extrinsic: Physical trauma, medications, and toxins

IRON DEFICIENCY ANEMIA

        Iron deficiency anemia typically results when the intake of dietary iron is inadequate for hemoglobin synthesis. The body can store about one fourth to one third of its iron, and it is not until those stores are depleted that iron deficiency anemia actually begins to develop. It is defined as anemia associated with either inadequate, absorption or excessive loss of iron; it is chronic, microcytic and hypochromic anemia.

ETIOLOGY

• In children, adolescents, and pregnant women, inadequate iron in diet; required to keep up with increased growth.
• For adults, blood loss (from ulcers, gastritis, inflammatory bowel disease, or gastrointestinal tumors)
• In premenopausal women, menorrhagia
• In chronic alcoholics, chronic blood loss from gastrointestinal tract
• Iron malabsorption after gastrectomy or with celiac disease

CLINICAL MANIFESTATION

Body System: Integumentary

Mild (10-14 g/dl): None

Moderate (6-10 g/dl): None

Severe (<6 g/dl): Pallor, jaundice, pruritis

Body System: Eyes

Mild (10-14 g/dl): None

Moderate (6-10 g/dl): None

Severe (<6 g/dl): Icteric conjunctiva and sclera, blurred vision

Body System: Mouth

Mild (10-14 g/dl):  None

Moderate (6-10 g/dl): None

Severe (<6 g/dl): Glossitis, smooth tongue

Body System: cardiovascular

Mild (10-14 g/dl): Palpitation

Moderate (6-10 g/dl): increased palpitations, bounding pulse

Severe (<6 g/dl): tachycardia, systolic mummur, angina, MI

Body System: Pulmonary

Mild (10-14 g/dl): Exertional dyspnea

Moderate (6-10 g/dl): Dyspnea

Severe (<6 g/dl): Tachypnea, orthopnea, dyspnea

Body System: neurologic

Mild (10-14 g/dl): None

Moderate (6-10 g/dl): Roaring in ears

Severe (<6 g/dl): headache, vertigo, irritability, impaired though process

Body System: Gastrointestinal

Mild (10-14 g/dl): none

Moderate (6-10 g/dl): none

Severe (<6 g/dl): anorexia, hepatomegaly, splenomegaly, difficulty in swallowing, sore mouth

Body System: musculoskeletal

Mild (10-14 g/dl): none

Moderate (6-10 g/dl): none

Severe (<6 g/dl): bone pain

Body System: general

Mild (10-14 g/dl): none

Moderate (6-10 g/dl): fatigue

Severe (<6 g/dl): sensitivity to cold, weight loss, lethargy

DIAGNOSTIC EVALUATION

• History and physical examination:
  • History: Ask the patient for socioeconomic status, any injuries, any disease etc
    • In physical examination check the vital signs temperature, pulse, respiration, blood pressure. Assess the skin color and signs of anemia. Check the body weight.
• Red blood cell size and color: with  iron deficiency anemia, red blood cells are smaller and paler in color than normal
• Hematocrit: this is the percentage of blood volume made up by red blood cells. Normal levels are generally between 34.9 and 44.5 percent for adult women and 38.8 to 50 percent for adult men. These values may change depending on age.
• Hemoglobin: lower than normal hemoglobin levels indicate anemia. The normal hemoglobin range is generally defined as 13.5 to 17.5 grams (g) of hemoglobin per deciliter (dL) of blood for men and 12.0 to 15.5 g/dL for women. The normal ranges for children vary depending on the child’s age and sex.
• Ferritin: this protein helps store iron in body, and a low level of ferratin usually indicates a low level of stored iron
• Endoscopy: to check for bleeding from a hiatal hernia, an ulcer or the stomach with the aid of endoscopy
• Colonoscopy: to rule out lower intestinal sources of bleeding
• Ultrasound: women may also have a pelvic ultrasound to look for the cause of excess menstrual bleeding, such as uterine fibroids.

MANAGEMENT

        To treat iron deficiency anemia, it is recommend taking iron supplements.

MEDICAL MANAGEMENT

• Oral iron preparations – ferrous sulfate, ferrous gluconate, and ferrous fumarate available
• In case, oral iron is poorly absorbed or poorly tolerated, or iron supplementation is needed in large amounts, intravenous or intra muscular administration of iron dextran needed.
• Before parenteral administration, a small test dose administered to avoid risk of anaphylaxis
• Emergency medications (e.g. ephinephrine) should be close at hand. If no signs of allergic reaction occurred after 30 minutes, remaining dose administered.
• IM injection causes local pain and stain skin. Side effects minimized by using Z-track technique for administering iron dextran deep into gluteus maximus muscle
• Because of problems with IM administration, IV route is preferred.

DIETARY MANAGEMENT

Foods rich in iron include:

• Red meat
• Pork
• Poultry
• Seafood
• Beans
• Dark green leafy vegetables, such as spinach
• Dried fruit, such as raisins and apricots
• Iron – fortified cereals, breads and pastas
• Peas

Choose foods containing vitamin C to enhance iron absorption

To enhance the body’s absorption of iron by drinking citrus juice or eating other foods rich in vitamin C at the same time. Vitamin C in citrus juices, like orange juice helps body to better absorb dietary iron.

Vitamin C is also found in:

• Broccoli
• Grape fruit
• Kiwi
• Leafy greens
• Melons
• Oranges
• Peppers
• Strawberries
• Tangerines
• Tomatoes