Hematologic Growth Factors

Question 1

What kind of dietary iron is best absorbed?

Answer 1

Heme iron - lots in red meat.

Question 2

What determines the body’s iron content? How is it stored? How is it transported?

Answer 2

Absorption. It is stored with Ferritin and transported with Transferrin.

Question 3

How is iron eliminated?

Answer 3

The body has no way to excrete iron. It is lost by sloughing of intestinal cells.

Question 4

So if iron can’t be eliminated, how is it regulated?

Answer 4

By ferritin synthesis - when iron is high, more ferritin is synthesized. When it is low, more is transported to the marrow for erythropoeisis.

Question 5

Acute Iron Toxicity

Answer 5

Seen in young children. Necrotizing gastroenteritis. Treatment is irrigation and chelation.

Question 6

Chronic iron toxicity

Answer 6

Hemochromatosis - organ failure and death.

Question 7

Adverse effects of iron salts

Answer 7

Nausea, epigastric distress, abdomina cramps, constipation, diarrhea, black stools.

Question 8

Vitamin B12 importance

Answer 8

Remember biochem? It is needed to convert folate to its active form.

Question 9

B12 deficiency

Answer 9

Neurologic syndrome - parasthesia, weakness, leading to ataxia. Irreversible.

Question 10

Mechanisms of B12 deficiency

Answer 10

Dietary (rare, maybe in vegetarians), Intrinsic factor problems (malabsorbtion)

Question 11

Folic acid importance

Answer 11

Precursor to nucleotides. If you can’t make DNA, you will get macrocytic normochromic anemia.

Question 12

Epoetin Alpha - what is it?

Answer 12

Glycosylated protein produced using recombinant DNA. It is produced by the kidney and stimulates erythroid proliferation and differentiation.

Question 13

Epoetin Alpha indications

Answer 13

Anemia due to renal failure or other disorders.

Question 14

Epoetin Adverse Effects

Answer 14

Hypertension, Thrombosis, Iron Deficiency, Hypertensive Encephalopathy and seizure.

Question 15

Darbepoetin alpha mechanism

Answer 15

Stimulates progenitor cells to produce Epoetin. Slow clearance. Long T 1/2

Question 16

G-CSF effects and important use

Answer 16

Stimulates progenitor cells already committed to neutrophil lineage to make new neutrophils and activate already extant neutrophils. It is important in stem cell transplantation because it pushes stem cells into the peripheral blood.

Question 17

GM-CSF effects

Answer 17

Stimulates proliferation and differentiation of granulocytic progenitor cells, leading to more granulocytes, eosinophils, basophils, and monocytes.

Question 18

Adverse effects of G-CSF

Answer 18

bone pain, local skin reactions, necrotizing vasculitis, splenomegaly.

Question 19

Adverse effects of GM-CSF

Answer 19

Fevers, flu like syndrome, bone pain, diarrhea, malaise, arthralgias, myalgias, capillary leak syndrome, peripheral edemas, pleural and pericardial effusions.

Question 20

Thrombopoeitic Growth Factors

Answer 20

Interleukin -11 - Megakaryocytes, thrombocytes

Thrombopoeitin - Megakaryopoeisis increasing platelet count.