Heme #2: Normocytic & Macrocytic Anemias

Question 1

MC normocytic anemia

Answer 1

Anemia of chronic disease

Question 2

What are the three main factors that decrease serum iron in anemia of chronic disease?

Answer 2

-Increased hepcidin: acute phase reactant that blocks release of iron from macrophages and reduces GI absorption of iron.

-Increased ferritin: acute phase reactant that sequesters iron into storage.

-Erythropoietin inhibition: via cytokines

Question 3

Diagnostics for anemia of chronic disease
-CBC
-Iron studies (one thing differentiates from iron deficiency anemia)

Answer 3

-CBC: mild normocytic normochromic anemia

-Iron studies: normal to increased ferritin** + decreased TIBC + decreased serum iron. Normal/low transferrin saturation.

Question 4

Management for anemia of chronic disease

Answer 4

-Treat underlying disease to correct anemia
-Erythropoietin-alpha if renal disease

Question 5

Labs for anemia of chronic disease
-Serum Iron:
-TIBC:
-Ferritin

Answer 5

Serum iron: decreased
TIBC: decreased
Ferritin: increased

Question 6

Labs for iron deficiency anemia
-Serum iron:
-TIBC:
-Ferritin:

Answer 6

-Serum iron: decreased
-TIBC: increased
-Ferritin: decreased

Question 7

Macrocytic Anemia (MCV is…)

What are the two anemias in this category?

Answer 7

-MCV > 100

B12 and Folate Deficiencies

Question 8

B12 (Cobalamin) Deficiency
-Sources
-Absorption
-Pathophysiology

Answer 8

-Sources: animal in origin (meats, eggs, dairy)
-Absorption: B12 released by stomach and combines with intrinsic factor and absorbed in distal ileum
-B12 deficiency causes abnormal synthesis of DNA

Question 9

What are the two etiologies of B12 deficiency?

Answer 9

-Decreased absorption: Pernicious anemia MCC (lack of intrinsic factor due to parietal cell antibodies), Crohn Disease, Chronic alcohol use, H2/PPI’s, Metformin

-Decreased intake: vegans

Question 10

Symptoms of B12 deficiency (similar to folate, but HAS _________)

Answer 10

Neuro abnormalities: symmetric paresthesias (MC initial symptom), lateral and posterior spinal cord demyelination (ataxia, vibratory, sensory, propioception deficits), decreased DTR’s, Positive Babinski, seizures

-Fatigue, pallor, exercise intolerance
-Glossitis, diarrhea, malabsorption

Question 11

What does a CBC with peripheral smear show with B12 deficiency?

What lab distinguishes B12 from folate deficiency?

Answer 11

-Macrocytic anemia + megaloblastic anemia (hypersegmented neutrophils, macro-ovalocytes)

-Increased methylmalonic acid

-Also has increased homocysteine

Question 12

Management for B12 deficiency

Answer 12

Start with IM B12 weekly until corrected, then monthly

Question 13

How often do patients with pernicious anemia need injections of B12?

Answer 13

Lifelong monthly injections

Question 14

If the B12 deficiency is due to a dietary deficiency, what should you give them?

Answer 14

Oral B12 replacement

Question 15

Etiologies of Folate Deficiency

Answer 15

-Inadequate intake (MCC): alcoholics, unbalanced diet
-Increased requirements: pregnancy, malignancy, psoriasis
-Impaired absorption: Celiac, IBD, diarrhea
-Impaired metabolism: Methotrexate, Trimethoprim, antiseizure medications
-Loss: dialysis

Question 16

Symptoms of Folate Deficiency

Answer 16

-Similar to B12, but no neuro symptoms

Question 17

What is one, extremely rare symptom of Folate deficiency that can occur?

Answer 17

Chlorosis (pale, faintly green complexion)

Question 18

CBC with smear for Folate Deficiency shows:

What other labs are there for folate deficiency?

Answer 18

-Macrocytic anemia + megaloblastic anemia (hypersegmented neutrophils, macro-ovalocytes)

Increased homocysteine

Normal methylmalonic acid (distinguishes B12 from folate)

Question 19

Management for folate deficiency anemia

Answer 19

-Oral folic acid