Robbins 14: Anemia Review Flashcards
Anemias are characterized by
- ↓ RBC
- ↓ Hct
- ↓ Hb
What is RDW and what does it tell us?
- Red cell distribution width = Measure of variability of RBC size
- Wide (↑) RDW = Reactive phenomenon seen in anemia when our BM is functioning properly: marrow is pumping out reticulocytes (larger cells)
What is MCHC?
- Average concentration of Hgb in RBC
What is MCH?
Mean cell hemoglobin = average mass of Hgb/RBC
What qualifies as Anemia in M and W?
Men: Hb < 13
Women: Hb <12
Microcytic anemias are due to…
↓ hemoglobin in the RBC due to:
- Loss of globins
- Loss of iron
- Loss of heme
Normocytic anemias are due to…
↑ destruction (hemolysis)/blood loss or ↓ production of RBC by BM.

Patient presents with normocytic anemia.
How do differentiate the cause?
Reticulocyte count
-
↑ reticulocyte count ➔ ↑ destruction (hemolytic anemia)
- BM has NL response to anemia
- ↓ reticulocyte count ➔ underproduction

Macrocytic anemias are due to…
Abnormalities that impair maturation of erythroid precursors in BM
Types of Microcytic Anemia
Iron LAST
- Iron-deficiency
- Lead poisoning
- Anemia of chronic disease (mostly, normocytic)
- Sideroblastic Anemia
- Thalassemias
What are Microcytic Anemias that occur due to ↓ iron?
- Iron-deficiency anemia
- Anemia of Chronic Disease (iron is trapped as ferritan)
What are Microcytic Anemias that occur due to ↓ globins?
Thalassemias
What are Microcytic Anemias that occur due to ↓ heme?
- Lead poisoning
- Sideroblastic anemia
Types of Macrocytic Anemias
- Megaloblastic Anemias (B12/folate deficiency/ pernicious anemia): ABNL DNA synthesis
- Other: Alcoholism and liver failure
Morphology of Megaloblastic Anemias
- Macro-ovalocytes
- Hypersegmented neutrophils (>5 lobes)
- Anisocytosis (variation in size)
- Poikilocytosis (variation in shape)
What are the Hct and MCV in Megaloblastic anemia?
- INC MCV
- DEC Hct
Normocytic anemias can be hemolytic or NON-hemolytic
Types of normocytic, hemolytic anemias due to intrinsic causes
What is the reticulocyte count?
↑ Reticulocytes (>2%)
- Hereditary Spherocytosis
- Paraoxysmal Nocturnal Hemoglobinuria
- G6PD Deficiency
- Sickle Cell Anemia
- HbC Disease

Normocytic anemias can be hemolytic or NON-hemolytic
Types of normocytic, hemolytic anemias due to extrinsic causes
What is the reticulocyte count?
↑ Reticulocytes (>2%)
- AI Hemolytic Anemia (AIHA)
- Microangiopathic Hemolytic Anemia (MAHA)
- Mechanical
- Infection

What 2 normocytic hemolytic anemias are due to membrane defects (intrinisic)?
- Heriditary spherocytosis
- Paroxysmal Noctural Hemoglobinuria
When do we see Aplastic Crisis via Parvovirus B19?
Chronic hemolytic anemias
- Sickle Cell Anemia
- Hereditary Spherocytosis
- Beta-thalassemia major
When do you see back/abdominal pain in anemia?
- Paroxysmal Nocturnal Hemoglobinuria
- G6PD Deficiency
Anytime RBC is damaged, it is removed via _____
Spleen (extravascular hemoloysis)
Extravascular hemolysis is due to what?
- Damage to membrane
- Poor deformability
- Opsinozation
Intravascular Hemolysis is due to what?
- Mechanical trauma (narrow vessels or mechanical heart valves)
- Compliment fixation
- Intracellular parasites (malaria)
- Extracellular toxins
Types of Normocytic Hemolytic anemias that undergo
Extravascular Hemolysis
- Hereditary Spherocytosis
- Sickle cell disorder
- G6PD Deficiency (extravascular + intravascular)
- Autoimmune hemolytic anemia (AIHA)
Types of Normocytic Hemolytic anemias that undergo
Intravascular Hemolysis
- Mechanical hemolysis
- Paraoxysmal Nocturnal Hemoglobinuria
- Microangiopathic Hemolytic Anemias (DIC, TTP, HUS)
Findings in intravascular hemolysis
- Schistocytes
- Hemoglobinuria + hemoglobinemia + hemosiderinuria
- ↓ Haptoglobins
- ↑ Unconjugated BR
Findings in extravascular hemolysis
Treatment
- Spherocytes
- No hemoglobinuria/hemosiderinuria
- Anemia + splenomegaly + jaundice
- Treatment = splenectomy
Pt has no RBC in urine, but (+) Hgb, what do they have?
- Hemolysis
- Rhadomyolysis
Findings in Hereditary Spherocytosis
- ↑ RDW
- NL - ↓ MCV
- ↑ MCHC (because RBC is smaller, but same volume)
- ↑ fragility to osmotic fragility test
- Spherocytes + Howell Jolly Bodies
Findings in G6PD Deficiency
Stress makes me eat bites of fava beans with Heinz Ketchup
- Heinz bodies: RBC with dark areas due to oxidized Hgb that has precipitated
- Bite cells
Complications of PNH
- Venous thrombosis
- AML
Diagnosis and treatment of PNH
- Flow cytometry to detect RBC deficient in GPI-linked proteins ; (-) Combs test
- Eculizimab: monoclonalAB used to prevent C5 => C5a conversion, reduce risk by 90%
Does sickling occur in Sickle Cell Trait?
Only under SEVERE hypoxia and in renal medulla (↑ risk of renal medullary carcinoma)
Histology in B-thalassemia
- Microcytosis
- Hypochromoia
- Anicysotiss (↑RDW)
- Poikilocytosis
- Basophilic stippling: aggregation of RNA due to toxic injury (seen in thalassemias + lead poisoning)
- Nucleated RBC
- Target cells (HALT, said the hunter to his target)
Which value is diagnostially useful in W of childbearing age who are at risk for both B-thalassemia and iron deficiency?
HbA2: ↑ in-thalasemia minor
Cause sof Warm IHA (IgG Ab)
- Idiopathic (MC)
- AI Disorder: SLE
- Drugs (Methyldopa, Penicillin, Cephalosporin)
- Lymphoid neoplasms: NHL and CLL
Causes of Cold IHA (IgG Ab)
- Myoplasma pneumonia
- EBV
- CLL =>
Findings in IHA
- Spherocytes (MC in WARM)
Findings in Microangiopathic Hemolytic Anemia
Schistocytes