Naplex 2026 - Anemia Ch 35

Define anemia

A decrease in red blood cells (RBCs), hemoglobin (Hgb) and/or hematocrit (Hct)

Leads to reduced oxygen delivery.

What is hemoglobin (Hgb)

Iron-rich protein found in RBCs that carries oxygen

What is hematocrit (Hct)

% of RBC volume compared to the total blood volume

What are reticulocytes

Immature RBCs, formed in the bone marrow

What are erythrocytes

Mature RBCs

What are some causes for anemia?

1) Impaired RBC or Hbg production

2) Increased RBC destruction: hemolysis

3) Nutritional deficiencies: iron, folate, vitamin B12

4) A complication from a disease such as CKD or cancer

What are the 3 main nutritional deficiencies that can lead to anemia

Iron

Folate

Vitamin B12

Sx from prolonged/severe anemia?

-Fatigue

-Weakness

-SOB

-Exercise intolerance

-HA

-Dizziness

-Pallor

Due to reduced oxygen delivery

What is Mean corpuscular volume (MCV)

The size or avg volume of RBCs

If a pt has low Hgb/Hct ± S/sx of anemia, then you check MCV:

If MCV is low (<80 fL) this is called ____ anemia

If MCV is high (>100 fL) this is called ____ anemia

If MCV is normal (80-100) this is called ____ anemia

If MCV is low (<80 fL) this is called microcytic anemia

If MCV is high (>100 fL) this is called macrocytic anemia

If MCV is normal (80-100) this is called normocytic anemia

A likely cause for microcytic anemia is ....

Iron deficiency

Some causes for macrocytic anemia include... (6)

1) Vitamin B12 deficiency (diet or autoimmune)

2) Folate deficiency (diet)

3) Alcohol use disorder

4) Decreased GI absorption due to Crohn's disease, celiac disease or gastric bypass

5) Pregnancy

6) Long-term use of metformin, H2RAs or PPIs

Likely causes for normocytic anemia includes (5)

1) Acute blood loss

2) Malignancy

3) CKD

4) Bone marrow failure (aplastic anemia)

5) Hemolysis

What is ferritin

Iron stores

What is the most common nutritional deficiency in the US?

Iron

What pt populations require an increase in iron?

1) Pregnancy

2) Lactation

3) Infants

List the common causes for iron deficiency (6)

1) Vegetarian or vegan diet

2) Heavy menses

3) PUD

4) High gastric pH (eg use of PPIs)

5) GI disorders: celiac disease and IBD

6) Gastric bypass

List the lab findings consistent with iron deficiency anemia (IDA) aka microcytic anemia

Decrease in (6) markers

Increase in (1) marker

Decrease in:

1) Hgb

2) MCV (< 80 fL)

3) Reticulocyte count

4) Serum iron

5) Ferritin

6) TSAT (transferrin saturation)

Increase in:

1) TIBC (Total iron binding capacity)

What is the treatment regimen + counseling tips for iron deficiency, using oral tablets

Take 1 tab PO daily or every other day.

Take on an empty stomach (1 hr before or 2 hr after meals) for best absorption.

Avoid H2RAs and PPis; separate admin from antacids.

Sustained-release or enteric-coated iron tablets cause less ___ ___ but are not recommended due to __ ___

Sustained-release or enteric-coated iron tablets cause less GI irritation but are not recommended due to poor absorption

What is the general lab goal after starting oral iron tx for IDA

An increase in Hgb after 1-2 weeks

How long to continue oral iron tx for IDA?

For 3-6 months or until iron stores return to normal.

What is the dose in ferrous sulfate tablets (mg? elemental iron?)

365 mg (65 mg elemental iron)

What is the boxed warning for iron tablets

Accidental overdose in children can cause fatal poisoning. In case of overdose, go to ER or call poison control immediately, even if asymptomatic.

What are common SE of taking iron tablets

Constipation (dose related)

Dark and tarry stools

What is the antidote for iron overdose? (generic and brand name)

Deferoxamine (Desferal)

Why do antacids need to be separated from iron administration?

And why do we have to avoid H2RAs and PPIs?

Increasing gastric pH will decrease iron absorption

What can be taken to help increase iron absorption?

Vitamin C aka ascorbic acid

Iron is a polyvalent cation that can DECREASE absorption of other drugs by binding/chelating with them in the GI tract.

Separate administration is needed with the following meds (5)

1) Quinolones

2) Tetracyclines

3) Bisphosphonates

4) Levothyroxine

5) INSTIs (Integrase strand transfer inhibitors)

T/F: There is no difference in efficacy among the oral iron tablets, or among the IV iron formulations.

T

Due to cost and the risk of more severe ADR, IV iron is restricted to the following pt populations (3)

1) CKD on hemodialysis

2) Receiving erythropoiesis stimulating agents (ESAs)

3) Unable to tolerate oral iron

Name two IV iron products and their brand names

1) Iron sucrose (Venofer)

2) Ferumoxytol (Feraheme)

What is the boxed warning for Iron dextran

Serious and sometimes fatal anaphylactic rxns. All pts should be given a test dose prior.

What is the boxed warning for Ferumoxytol

Serious and sometimes fatal anaphylactic rxns.

Warning for all IV iron products

Hypersensitivity rxns

What is pernicious anemia?

A common cause of vitamin B12 deficiency.

It's an autoimmune condition caused by antibodies to intrinsic factor, which is required for vitamin B12 absorption.

What is the tx and duration for pernicious anemia

Vitamin B12

Lifelong

Lab markers for macrocytic anemia

Decrease in:

Hgb

Reticuloctye count

Vitamin B12 and/or folate

Increase:

MCV

± Methylmalonic acid (deficiency in B12)

± Homocysteine metabolism (deficiency in folate and B12)

Vitamin B12 is required for the metabolism of .... in the body

Methylmalonic acid and homocysteine

Folate is required for the metabolism of ... in the body

Homocysteine

Vitamin B12 deficiency can result in ... if untreated

Neurologic dysfunction including cognitive impairment and peripheral neuropathy which can become IRREVERSIBLE if untreated

Folic acid deficiency causes what sx

Ulcerations of the tongue and oral mucosa

What is 1st line tx for severe vitamin B12 deficiency

Cyanocobalamin injections (B12)

What vitamin is folic acid

Vitamin B9

1st line tx for folate deficiency is usually

oral folic acid / folate / vitamin B9

What is Nascobal and how do you use it

Cyanocobalamin (B12) nasal spray

Use in one nostril once weekly

What is the route of admin for cyanocobalamin (B12) injection

IM or deep Subq

What is erythropoietin (EPO)

A hormone made by the kidneys that simulates bone marrow to produce RBCs

Anemia of chronic disease (CKD or cancer) is often due to a deficiency of ....

Erythropoietin (EPO)

What is 1st line tx for anemia of chronic disease (CKD or cancer)

1) IV iron (preferred over oral)

2) Erythropoiesis-stimulating agents (ESAs):

Epoetin alfa

Darbepoetin alfta

Name the Erythropoiesis-stimulating agents (ESAs) and their brand names

1) Epoetin alfa

=> Epogen, Procrit

2) Darbepoetin alfta

=> Aranesp

The ___ guidelines recommend iron in all pts with anemia of CKD.

KDIGO (Kidney Disease Improving Global Outcomes)

A pt with "anemia of chronic disease" has been on IV iron but their Hgb remains < ___ g/dL. A erythropoiesis-stimulating agent can be used.

Hgb < 10 and on iron

=> start ESA

If Hgb approaches or exceed __ g/dL, then the ESA dose needs to be decreased or interrupted

Hgb 11 g/dL

If Hgb approaches or exceed 11 g/dL, then the ESA dose needs to be .....

decreased or interrupted

What is required for ESAs to be effective in the body?

Adequate iron stores

Epoetin alfa (Epogen, Procrit) for anemia of CKD: what is the dosing regimen

3x / week

Boxed warnings for Epoetin and Darbepoetin (4)

1) Increased risk of death, MI, stroke, VTE and thrombosis

2) Use lowest effective dose

3) CKD: increased risk of death when Hgb lvl > 11 g/dL

4) Select cancers: do not use if anticipated outcome is cure from cancer (it can worsen tumors)

Epoetin and Darbepoetin can do what to BP?

Increase it

It can cause HTN

Side effect of ESAs

Arthralgia (joint pain)

Lab monitoring for ESAs (5)

1) Hgb

2) Hct

3) TSTAT

4) Serum ferritin

5) BP

(IV/oral) route of ESAs is recommended for pts on hemodialysis

IV

Epoetin and Darbepoetin storage/handling

Fridge; do not shake

Darbepoetin (Aranesp) regimen

Weekly

Half-life of Epoetin vs Darbepoetin

Darbepoetin has half-life 3x LONGER than Epoetin, that is why darbepoetin is dosed once weekly and epoetin is 3x/week

Two common mechanisms of drug-induced hemolytic anemia

1) Immune-mediated:

Drug binds to RBCs and triggers antibodies to destruction

2) Glucose-6-phosphate dehydrogenase (G6PD) deficiency

The MD suspects a pt developed immune-mediated hemolysis. How can this be confirmed?

With a positive direct Coombs test

It detects antibodies stuck to the surface of RBCs

What is the relationship of G6PD enzyme and blood?

What happens if a pt is G6PD deficient?

G6PD enzyme protects RBCs from oxidant injury.

If a pt is G6PD deficient, RBCs can hemolyze after exposure to oxidative stress from high-risk medications. Can cause drug-induced hemolytic anemia

List common drugs that can cause immune-mediated anemia

Use mneumonic

Quite Quick Positive Coombs Lab Reveals Immune Mediated Situation

Q = Quinine

Q = Quinidine

P = Penicillin

C = Cephalosporins

L - Levodopa

R = Rifampin

I = Isoniazid

M = Methyldopa

S = Situation

List common drugs that can cause hemolytic anemia with G6PD deficiency pts

Use mneumonic

Patients Not Making Sufficient RBC Please Don't Quit Quietly

P = Pegloticase

N = Nitrofurantoin

M = Methylene Blue

S = Sulfonamides

R = Rasburicase

P = Primaquine

D = Dapsone

Q = Quinidine

Q = Quinine

Where are the injection sites for ESAs?

Abdomen around belly button

Upper/outer arms

Thighs

Hips to the back