Anemia due to Decreased RBC Production

Question 1

Describe some of the major causes for underproduction anemia

Answer 1

• iron deficiency
• chronic inflammation and infection (malignancy)
• lead intoxication
• renal disease/failure
• endocrine (thyroid and adrenal)

Question 2

chronic inflammation and infection: pathophysiology

Answer 2

TNF decreases iron availability from stores and ↓EPO production, INF-beta inhibits erythropoiesis.
Infection/Inflamm: IL-1 diminishes iron mobilization and EPO production, INF-gamma inhibits prolif of erythroid precursors

Question 3

lead intoxication: pathophysiology

Answer 3

Lead inhibits synthesis of protoporphyrin and the enzyme that ligates iron to the porphyrin ring.

Question 4

renal disease/failure: pathophysiology

Answer 4

EPO cannot be produced (its made in the kidneys)

Question 5

chronic inflammation and infection: typical clinical findings

Answer 5

Dependent on underlying disease, may include: fever, arthralgia, arthritis, fatigue. For infection, symptoms and signs relate to the focus (pain, cough, swelling)

Question 6

lead intoxication: typical clinical findings

Answer 6

Personality changes, irritiable, headache, weakness, wt loss, adb pain, vomiting

Question 7

renal disease/failure: typical clinical findings

Answer 7

Related to those with renal deficiency: fatigue, pallow, low exercise tolerance, dyspnea, tachypnea

Question 8

endocrine (thyroid): typical clinical findings

Answer 8

Hyper or hypo activity, weight gain or loss, systemic skin, nail, hair changes.

Question 9

endocrine (adrenal): typical clinical findings

Answer 9

nausea, vomiting, dehydration, weakness, circulatory collapse

Question 10

chronic inflammation and infection: typical lab features

Answer 10

Mild-mod anemia (Hgb 8-12 gm/dL)—severity is proportional to underlying disease, may be normochromatic/normocytic or microcytic with some hypochromia. ↓serum Fe, total iron binding capacity (TIBC), EPO for Hct, retic count. Nrml to ↑ ferritin (Fe stores)

Question 11

lead intoxication: typical lab features

Answer 11

Mild-mod anemia, ↓ retic count, microcytosi and mild hypochromia, basophilic stippling, ↑ zinc protoporphyrin, may see concurrent iron def (“inner city triple whammy”), ↑ lead levels

Question 12

renal disease/failure: typical lab features

Answer 12

Don’t see anemia until kidney function is ˂40%. Mod-sev anemia. Hgb: 5-9 mg/dL. Normochromic/normocytic. ↓retic, ↓EPO, ↓production

Question 13

endocrine: typical lab features

Answer 13

↓retic count and index in all
Hypothyroid: mild anemia, normochromic/normocytic. May be microcytic or macrocytic. Hyperthryroid: usually normocytic, may be microcytic. Adrenal: mild anemia, normocytic

Question 14

Describe the pathophysiology of the anemia of chronic disease

Answer 14

??

Question 15

Describe the rationale and indications for the use of erythropoietin in the management of underproduction anemia

Answer 15

used in specific conditions when there is an absolute deficiency or where EPO levels are decreased out of proportion to the degree of anemia and administration is known to induce a response.

Question 16

Explain the biochemical basis for B12 and folate deficiency leading to a macrocytic anemia

Answer 16

a. Both are critical co-factors for normal hematopoiesis (in the synthesis of methionine from homocysteine). Deficiencies of folic acid and Vit B12 affect the maturation process of red cell precursoes in the marrow. The cells increase in size, arrest in S phase of mitosis, undergo destruction, resulting in ineffective erythropoiesis and anemia