Anemia

Question 1

Pathophysiology of Anemia

Answer 1

Decreased iron-carrying capacity of blood

Iron-deficiency anemia

• caused by poor intake or blood loss (acute or chronic)
• treated with iron replacement

Folic Acid deficiency anemia

• Seen in alcoholism, chronic malnutrition, fad diets, and diets low in vegetables
• Drugs: Dilantin, sulfamethoxazole/trimethoprim, oral contraceptives, methotrexate

Pernicious anemia

• Vitamin B12 deficiency leads to macrolytic-normochromic anemia
• Vegetarians, vegans, genetic predisposition, autoimmune disease

Question 2

Anemia: Goals of Treatment

Answer 2

Restore hemoglobin (Hgb) and red blood cell count to normal levels to maintain oxygen-carrying capacity of blood

Question 3

Iron-Deficiency Anemia: Prevention and Treatment

Answer 3

Prevention:

• Adequate intake via iron-rich diet
• Monitor in periods of rapid growth (infancy, adolescence, pregnancy)
• Replacement in infants 1 mg/kg/day starting at 4 months (2mg/kg/day in preterm infants)

Treatment

• iron replacement based on age
• dose divided to 3 doses per day

Question 4

Iron Deficiency Anemia: Monitoring & Outcome Evaluation

Answer 4

Monitoring

• Reticulocyte count 5-10 days after starting therapy
• Hgb, Hct, ferritin at 4 weeks, then at 3 months and then annually

Outcome Evaluation

• Return to normal Hgb, Hct, and ferritin levels should be determined
• If Hgb, Hct, ferritin do not return to normal levels, the patient should be evaluated for a source of blood loss in other pathology

Question 5

Iron Deficiency Anemia: Patient Education

Answer 5

Importance of prevention with adequate iron intake in diet

Administration

• Empty stomach if tolerated
• Three times per day is best
• May cause constipation (may need a stool softener)

Question 6

Folic Acid Deficiency Anemia: Risk groups

Answer 6

• Infants fed goat’s milk or powdered milk formula
• Vegetarians and vegans
• Pregnant women increases in daily requirement
• Patients with sprue, Crohn’s disease, giardial infections, and short bowel syndrome
• Patients taking drugs that affect folic acid absorption

Question 7

Folic Acid Deficiency Anemia: Prevention & Drug Therapy

Answer 7

Prevention

• Adequate dietary intake
• Folic acid supplementation in pregnancy

Drug Therapy for deficiency

• Oral folic acid 1-2 mg/day for 4-5 weeks
• Hgb levels start to rise in a week

Women of childbearing age and pregnant women should consume 0.4 mg to 0.8 mg/day

Question 8

Folic Acid Deficiency Anemia: Monitoring and Patient Education

Answer 8

Monitoring
- Follow Hgb/Hct in 4 weeks and then regularly

Education

• Need for folic acid
• Administration

Question 9

Pernicious Anemia: Cause

Answer 9

Caused by inadequate vitamin B12

• Defective secretion of gastric intrinsic factor, which is necessary for vitamin B12 absorption
• Vitamin B12 malabsorption in 10%-30% of adults older than age 50 years because of reduced pepsin activity and gastric acid secretion

Question 10

Pernicious Anemia: Prevention & Drug Therapy

Answer 10

Prevention
- eating foods high in vitamin B12 such as mollusks (e.g., clams), fortified breakfast cereals, liver, trout, salmon, milk, eggs

Drug Therapy

• Oral, IM, and intranasal vitamin B12 replacement
• Nutritional deficit: 1,000 mcg/day of cobalamin given until normal B12 levels
• Vitamin B12 therapy 1,000 mcg IM daily for 1 week followed by 100-1,000 mcg IM weekly for a month
• – Parenteral, nasal, or oral therapy: may be used once a patient’s B12 level return to normal
• – Parenteral: 1000 mcg of vitamin B12 IM monthly
• – Nasal: 500 mcg of cyanocobalamin weekly
• – Oral: 1000 mcg daily (least expensive)

Question 11

Pernicious Anemia: Monitoring & Patient Education

Answer 11

Monitoring:

• Reticulocyte counts, Hgb & Hct, iron, folic acid, & vitamin B21 serum levels prior to treatment, at 5-7 days of therapy, then frequently until Hgb & Hct are normal
• Monitor potassium levels
• Liver function tests every 2-4 weeks to monitor hepatotoxicity

Patient Education

• Disease process and need for lifelong therapy
• Vitamin B12 therapy regimen
• Monitoring

Question 12

Anemia of Chronic Disease

Answer 12

Occurs as a result of a disease process

Older adults

Patients with renal failure, osteomyelitis, TB, rheumatoid diseases, hepatitis, carcinoma, myeloma, lymphoma, and leukemia at risk

Question 13

Anemia of Chronic Disease: Treatment

Answer 13

• If associated with chronic renal failure or zidovudine-treated HIV: epoetin alfa 50 to 100 units/kg in adults and 50 units/kg in children dosed 3 times per week
• Epoetin alfa dose titrated to keep Hgb level between 1012 g/dL
• Dosage increased by 25% if Hgn is less than 10
• Epoetin alfa dose decreased by 25% if Hgb approaches 12 or increases greater than 1 in any 2 week period

Question 14

Sickle Cell Anemia: Pharmacodynamic & Prevention

Answer 14

• Universal newborn screening
• Autosomal recessive genetic disorder
• HgbS which distorts into sickle shaped RBC
• – Sickled cells obstruct microvessels

Prevention

• Immunizations
• Hydration

Question 15

Sickle Cell Anemia: Treatment

Answer 15

Multivitamin infusion daily

Evaluate for vitamin D deficiency

Prophylactic penicillin

Hydroxyurea (Droxia, Hydrea)