Anemia Flashcards
Lab values for iron deficiency anemia?
LOW:
Serum iron, transferrin saturation, ferritin, MCV
(Ferritin stores iron, transferrin binds iron, MCV is mean corpuscle volume)
HIGH:
TIBC (This is binding capacity - body can bind lots of iron when there isn’t much around!)
HgB and Hct are normal at first then get low over time (chronic)
What’s better - immediate or extended release iron?
Immediate release. Extended release results in less absorption
Should iron be given with food?
No, it decreases absorption
Adverse effects of iron admin?
Dark discoloration of feces
Constipation or diarrhea
N/V
Upset stomach
(All of these are dose relatd)
What options do we have for oral iron supplementation?
Ferrous sulfate
Ferrous sulfate excsiccated (30% absorption - highest)
Ferrous gluconate (13% absorption - lowest)
Ferrous fumarate
Drug interactions for oral iron therapy?
Antacids, tetracycline antibiotics, H2 blockers/proton pump inhibitors, levothyroxine, mycophenolate, and cholestyramine impair absorption
Levodopa and penicillamine chelate iron to reduce levels
Dosing for oral iron therapy?
150-200 mg daily divided into 2-3 doses
Take with an empty stomach, start low and titrate upwards
How long should oral iron therapy last?
3-6 months AFTER anemia has resolved, this allows for replenishment of the stores (not just increasing to normal levels)
When do we give parenteral iron therapy?
Inadequate response to oral therapy
Chronic kidney disease
Chemotherapy patients receiving erythropoiesis stimulating agents
Refusal of blood product administration (wut?)
Options for parenteral iron therapy?
Iron dextran
Sodium ferric gluconate
Iron sucrose
Ferumoxytol
How is parenteral iron therapy dosed?
Hgb deficit = target Hgb - observed
multiply by weight in pounds!!!
then
Add 600 for women, 1000 for men to get dose
Iron dextran - dosing? Adverse effects? Limitations?
100 mg daily until total dose is reached
Can give as a single IV infusion also
Adverse effects - anaphylaxis (black box warning)
MUST do test dose of 25 mg followed by 1 hour observation
Also worry about painful injection, flushing, hypotension, fever, chills, myalgia
Sodium ferric gluconate - dosing? adverse effects? limitations?
Indicated when pt is undergoing hemodialysis
125 mg IV daily (IV infusion only)
Adverse effects: Less risk for rash but still monitor for 30 mins post dose just in case
Cramps, nausea, vomiting, flushing, hypotension, gastric pain, rash, pruritis
Iron sucrose - dosing? Adverse effects? Limitations?
Indication is pts with CKD with or without hemodialysis
Dosing: 100 mg IV daily
adverse effects: Leg cramps, hypotension
Don’t give oral iron with this
Ferumoxytol - dosing? Adverse effects? Limitations?
Indicated in pts with CKD
Dosed 510 mg IV followed by 510 mg 3-8 days later
30 mg/s
Adverse effects: No test dose required, observe for 30 mins after dose
Diarrhea, constipation, nausea, dizziness, hypotension, peripheral edema
How do we monitor response to iron therapy?
Hgb and Hct weekly until stabilized
Serum iron/ferritin monthly (wait 48 hours after IV iron)
Iron toxicity: serum ferritin over 800 or transferrin saturation over 50%
Check 1 week after doses 100-200 mg, 2 weeks after larger doses
Lab values for VB12 deficiency?
MCV over 100 fL, vitamin B12 less than 150 pg/mL
LOW:
Hct
HIGH:
Homocysteine (converted to cysteine by B12, low B12 = low conversion = too much homocysteine)
MMA (Same as above)
Signs/symptoms of VB12 deficiency?
Late stage can cause psychosis, dementia
Can have paresthesia
What is the DRA of VB12?
2 mcg in adults
2.6 mcg in pregnancy or breast feeding
Typical western diet provided 5-15
What is the DRA of iron?
Men and postmenopausal women it’s 8
Women it’s 18 mg
Western diet provides between 12-15 mg
When do we treat VB12 deficiency?
Megaloblastic anemia
Neurologic disease from deficiency
Marginally low VB12 levels with high MMA/homocysteine levels
How to treat VB12 deficiency?
1-2 mg orally once daily, avoid times release
IM admin: 1000 mcg daily x 1 week, then weekly for 1 month, then monthly thereafter
If you want to go from IM to oral, just give 1 mg orally daily starting on the due date of the next injection
Monitoring for VB12 deficiency?
Rapid response (usually within a few days, with response to anemia in 1-2 months)
Folic acid deficiency - how much folic acid do we need daily?
400 mcg in adults
600 mcg in pregnancy
500 mcg in lactating women
