Term
| Which form of iron is given orally? |
|
Definition
| Ferrous and not ferric. NB that you shud Tx w/ oral iron for another 3-6 months. |
|
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Term
| What are some A/Es of oral iron Tx? |
|
Definition
| Nausea, epigastric discomfort, abdominal cramps, constipation & diarrhea |
|
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Term
| What are the three parental forms of iron? |
|
Definition
|
|
Term
| What are some of the other A/Es of iron dextran? |
|
Definition
| Headache, arthalgias, fever, nausea & vomiting, flushing and pruitus |
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Term
| Where do we see acute iron toxicity? |
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Definition
| Almost exclusively in children, they experience: necrotizing gastroenteritis, vomiting, abdominal pain, bloody diarrhea, shock, metabolic acidosis, coma, death |
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Term
| How do u Tx acute iron toxicity? |
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Definition
| Urgent bowel irritants, followed by Deferoxamine or deferasirox (?) (iron-chelator). NB that activated charcoal is effective in most toxins but not for iron. |
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Term
| Chronic iron toxicity is know as? |
|
Definition
| Hemochromatosis, which usually builds in the heart, liver and pancreas. Can be inherited or from transfusions for thalassemia major. |
|
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Term
| What form are the Vit. B12 in food? |
|
Definition
| Cyanocobalamin & hydroxocobalamin. Active forms are (deoxy)adenosylcobalamin & methylcobalamin |
|
|
Term
| What are some of the glycoproteins? |
|
Definition
|
|
Term
| Where is excessive Vit. B12 stored? |
|
Definition
|
|
Term
| What is the "methylfolate trap"? |
|
Definition
|
|
Term
| How does large amounts of folate correct the anemia caused by Vit. B12 deficiency? |
|
Definition
|
|
Term
| What causes the neurological Sx in megaloblastic anemia? |
|
Definition
| The lack of vit. B12 leading to a lack of methionine |
|
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Term
| When looking at megaloblastic anemia, what lab value will you look at? |
|
Definition
| Elevated serum homocysteine levels - Vit. B12 deficiency. NB that homocysteine may increase risk of atherosclerosis. Also note that labs will also show elevated methylmalonic acid, recall that Vit. B12 is needed for methylmalonly-CoA mutase which isomerizes methylmalonyl-CoA to succinyl-CoA |
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|
Term
| What are the neurological defects with lack of Vit. B12? |
|
Definition
|
|
Term
| Explain the Schilling test? |
|
Definition
|
|
Term
| Which form of parental Vit. B12 is preferred? |
|
Definition
| Hydroxocobalamin as its highly protein bound thus remains longer in circulation |
|
|
Term
| What kind of vascular Dz would u see in folate def? |
|
Definition
|
|
Term
| Folate on top of being needed to make purines is also needed to make? |
|
Definition
| dUMP to dTMP. NB that you get from THF to methyl-THF by serine transhydroxymethylase |
|
|
Term
| What three enzymes are involved in the dTMP cycle? |
|
Definition
| dTMP synthase, dihydrofolate reductase & serine transhydroxymethylase |
|
|
Term
| What do you know of that cause folate def? |
|
Definition
| Methotrexate and to a lesser extent, trimethoprim (inhibits dihydrofolate reductase) & pyrimethamine (antiparasitic) |
|
|
Term
| What effect does phenytoin have on folate def? |
|
Definition
| Long-term therapy can cause the def but only rarely cause the megaloblastic anemia |
|
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Term
|
Definition
|
|
Term
| What are EPO Rs a member of? |
|
Definition
| JAK/STAT superfamily of cytokine R's |
|
|
Term
|
Definition
|
|
Term
| What is the long-acting version of EPO? |
|
Definition
| Darbepoetin, it has two carbohydrate chains, which improve biologic activity (decreased clearance and T1/2 is 3X's that of EPO) |
|
|
Term
| What are some of the A/Es of EPO? |
|
Definition
| Hypertension and thrombosis; FDA also says that pts with chronic liver failure or CA and have a serum Hg level >12g/dL from EPO-like agents are at gr8er risk for thrombosis, or in advanced head & neck CA -> faster tumor growth |
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Term
| What are the two myeloid growth factors u know? |
|
Definition
| Filgrastim (G-CSF) & Sargramostin (GM-CSF) => stimulate the production and function of PMN's. NB they act on JAK/STAT R's on various myeloid progenitor cells |
|
|
Term
| What are the A/Es of myeloid growth factors? |
|
Definition
G-CSF - minimal but sometimes bone pain
GM-CSF - fever, arthralgias & capillary damage w/ edema.
NB that allergic rxns are rare |
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|
Term
|
Definition
|
|
Term
| How does hydroxyurea work? |
|
Definition
...
A/Es: BM supression & cutaneous vasculitis
NB that it is currently being used to Tx CML & polycythemia vera |
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