Anemia - Block 4 Flashcards
WHat is anemia?
Decrease in RBC, RBC mass, and Hgb concentration
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What values constitutes anemia?
Males: Hgb <13 g/L
Non pregnanct women: Hgb <12 g/L
What is the life span of RBC?
120 days
What is is the function of EPO?
Initiates and stimulates the production of RBCs
* prevent apoptosis -> proliferation and maturation
Describe the structure of Hgb?
- 2 a chains and 2 b-chains
- Chelated iron
What is transferrin?
Transport protein that delivers iron to bone marrow so it can be incorporated into Hgb
Where are old blood cells destroyed/broken down?
Spleen and narrow
What are the presnetations of anemia?
- SOB
- Fatigue
- Irritability
- DZ
- Weakness
- Tachycardia
- Vertigo
- HA
- Chest pain
- Ecchymoses
- Blood in sttol or urine
- Hematomas
- Neurologic
- Pale
- ALtered mental status
What type of anemia causes neurologic manifestations?
Vitamin B12 def
What is in a fishbone?
What are the elements of a CBC diagram?
What is the normal Hgb value?
Male: 14-17
Female: 12-16
What is normal MCV value?
80-100 fL
What are the functional defects of anemia?
- Hypoproliferative: marrow damage, iron def, decreases RBC stimulation
- Maturation dx: Iron, folate, vit b12 deficiency
- Hemorrhage/hemolysis: blood loss, autoimmune, hemolysis
Describe the types of anemia?
What are the labs associated with microcytic anemia?
- Serum iron
- Total iron binding capacity
- percentage transferrin saturation
- Serum ferritin
What are the labs associated with macrocytic anemia?
Folic acid and VIt B12
How should we diagnose anemia?
What is the most common type of deficinecy?
Iron
What is hepcidin?
Regulator of absorption, iron recycling, and iron mobilization from hepatic stores
What type of iron is best absorbed? What type of iron is in most Western diets?
Ferrous (Fe2+)
Ferric (Fe3+)
What is the daily iron recommendations?
Male and postmeno females: 8 mg
Menstruating females: 18 mg
What are the manifestations of ID?
- Iron stores reduced without reduced serum levels
- Iron stores depleted, but Hgb remains within normal ranges
- Hgb falls -> anemia
What is your earliest and most sensitive laboratory change in an iron panel?
Ferritn
What are the s/s for IDA?
- Alopecia
- Dry/damaged hair and skin
- Atrophic glossitis
- RLS
- Cold intolerance
- Pica
- Brittle nails
- Irritability
What are the components of an iron panel and how is that affected by IDA?
Total iron binding capacity (TIBC): elevated
Serum iron: decreased
Ferritin: decreased
Transferrin saturation: decreased
Why would TIBC be elevated in IDA?
Cells have a lot of capacity to bind to iron
What is the tx for IDA?
PO iron supplementation
Dosing:
* Adults: 100-200 mg elemental iron/day divided into 2-3 doses
* Children: 3-6 mg/kg/d in 3 doses
How long is PO iron tx duration?
continue treatment for 3-6 months after anemia resolved to replete stores & prevent relapse
What is your most prescribed iron product?
Ferrous sulfate
Describe the absorption of iron?
- Food decreases absorption as much as 50%, however does mitigate Gi upset
- Ferrous iron (Fe2+) > ferric (Fe3+)
* Polysaccaride iron complex -> ferric form that has less GI irritation
How much should Hgb levels increase when using iron?
1 g/dL Q2-3W
What are the ADRs of iron?
Constipation, dark/tarry stools
- Iron toxicity is reversed by deferoxamine
What is the difference between GI bleed and iron stool?
GI bleed: loose
Iron: hard and solid
When would parenteral iron be used?
- Failure and intolerance to PO
- Quick recovery
- COnjunction with ESA
- Anemia of CKD/other states unresponsive to ESAs alone
- Substitute for blood transfusions
How is parenteral iron dosed? ADR?
Weight based
N/V, hypersentitivity, life threatening -> slow infusion rate
What iron formulation requires a test dose before admin?
Iron dextran
When do you see improvement in IBD with PO iron?
- reticulocytosis in days
- increase in Hgb after ~ 2 wks
- normal levels of iron reached by 2 months
serum ferritin concentrations should return to normal (~6-12 months)
When does acute iron tox occur?
1-6 hr after ingestion
What is the tx for acute iron tox?
- Supportive therapy
- Iron chelation w/ deferoxamine
Who are more prone to chronic iron tx?
Chemo
Prolonged iron exposure
Tx for iron overload (chronic iron tox)?
Deferoxamine IM, IV, SC
Transferrin infusions
What are the tx options of anemia in CKD?
- iron
- ESA
When should iron be initiated in CKD patients?
KDIGO: TSAT ≤ 30% & ferritin ≤ 500 ng/mL
HD: IV iron
Non-HD: PO iron
- ESA is ineffective when iron stores are low
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When should ESA be initiated in CKD patients?
Initiation:
* Individualize for Non-HD pts w/ Hgb < 10 g/dL
* CKD 5D initiate ESA at Hgb between 9-10 g/dL; avoid Hgb <9 g/dL
Maintenacne:
* do not use to maintain Hgb > 11.5 g/dL -> thrombosis
* Do not exceed Hgb > 13 g/dL
What are the types of ESA?
Epoetin alfa
Darbepoetin
What is our Hgb target for ESA?
11-12 g/dL
No response after 8 weeks: DC
Montior Hgb twice weekly -> 2-6 weeks for dosage adjustment
What are causes of anemia due to inflammation?
- Chronic infection
- Chronic inflammation
- Malignancies
- Less common causes
What is the difference between ACD and ACI?
ACD: develops over months to yrs -> reflects severity of dx
ACI: develops over days, typically in the hospital
What are the factors that contribute to anemia inflammation?
- BLunted EPO response to anemia
- Disturbance of iron homeostasis
- Impaired proliferation of erythroid progenitor cells
Describe the labs of AI?
Ferritin and hepcidin increase
TIBC decrease
What is the tx for AI?
Iron
ESA: if patient is noncurative with non-myeloid tumors
RBC transfusion: if patient is curative
What are the labs of hemolytic anemia?
- Decreased Hgb/Hct and haptoglobin
- Reticulocytosis
- Abnormal peripheral blood smear
- Increased unconjugated bilirubin and lactate dehydrogenase
What is the tx for hemolytic anemia?
- Removal of offending drug
- Tx of underlying dx
- Transfusion as necessary
What are the causes of megaloblasic anemia?
- Vit B12 def
- FOlate
- Drug induced
Abnormal DNA metabolism -> large, immature RBCs
What are the causes of vit b12 def?
- Inadequate intake (alcoholics)
- Malabsorption
- Inadequate utilization
What is the recommended dietary allowanceof b12?
Adults: 2.4 mcg/d
Pregnant and breast-feeding women: 2.6 mcg/d
Common problem with B12 def?
Neurologic complications
Sources of B12?
- Fish
- Fortified cereals
- Liver
Labs of macrocytic anemia from B12 def?
- MSV (elevated)
- Low B12 and folate
What is the tx for macrocytic anemia?
Cyanocobalmin
How do we evalute B12 therapy?
Reticulocytosis: 3-5 days
Hgb: rise in first week and normalize in 1-2 months
Maintence: 3-6 months after initation
What is the recommneded amount of folate?
Adults: 400 mcg/day
Pregnant females: 600 mcg/day
Lactating females: 500 mcg/day
What is the lab findings of macrocytic anemia from folate def?
- MCV (elevated)
- Homocystein (elevated)
- Serum folate (decreased)
What is the tx for folate def anemia?
- Correct B12 first with cyanocobalmin
- Folic acid supplementation for 4 months
- CHeck for ADRs: site pain, flushing, malaise
How should we evaluate folic acid therapy?
- Reticulocytosis in first week
- Hgb/Hct begins to rise within 2 weeks reaches normal levels within ~ 2 months
- Increased alertness and appetite often occur early in treatment
What are drugs that cause B12 def?
Alcohol, metformin, PPI, H2RA
What is nonmegaloblastic anemia?
No impariment of DNA synthesis, normal B12 and folate
