Clinical Approach to Anemia Flashcards
What test is most helpful in Dx of Fe deficiency?
Ferritin
What red cell morphology is most suggestive of autoimmune hemolysis?
Microspherocyte
What simple test best defines inadequate marrow function in an anemic pt?
Reticulocyte count
Having a hyposegmented (2 lobes) neutrophil in a smear is a sign of:
myelodysplasia
If you see a smear with a TON of lymphocytes and they all appear “smeared”, what is going on?
Chronic Lymphocytic Leukemia (CLL)
If you see a “hairy” lymphocyte in a peripheral smear, think:
Hairy Cell Leukemia (HCL)
What is a normal reticulocyte percentage and count?
0.5-2.5% or 25-125x10^9
How do you calculate the corrected reticulocyte count? How do you determine if it is an adequate response?
(RC % x hct)/45
< 3 inadequate
> 3 adequate
What happens to reticulocyte count in acute blood loss and hemolytic anemia?
elevates
What happens to reticulocyte count in chronic blood loss?
drops due to Fe deficiency
Levels of these 5 things will be elevated in hemolytic anemia.
LDH Bilirubin Haptoglobin Plasma Free Hb Urine hemosiderin
In warm IHA, what antibody isotype will be specific for RBCs?
What causes it?
IgG
penicillin alters RBC surface proteins and IgG attacks them.
Complement may also be present
In cold IHA, what antibody isotype will be specific for RBCs?
What causes it?
IgM
Mono (viral)
Mycoplasma pneumonia (bacterial)
“IgM tends to drop off in the central body and it tends to be complement mediated, alone” - Dr. Weir
If you have yet unexplained anemia after smears, antibody tests, and cell counts, and a low retic. count, what do you do next?
Bone marrow analysis. Since you have ruled out blood loss, anemia may be due to lack of production.
Your pt has macrocytic anemia. What are you going to look for first?
Reticulocyte count
Your pt has macrocytic anemia and elevated reticulocyte count. What is in your differential?
hemolysis
acute blood loss
Your pt has macrocytic anemia and low retic. count. What are you going to look for now?
B12 and folate levels
Your pt has microcytic anemia. What are you going to look for now?
Ferritin levels
Your pt has microcytic anemia and low ferritin levels. What are you going to look for now?
Evaluate for blood loss
Your pt has microcytic anemia and normal ferritin levels. What are you going to do now?
Hb electrophoresis to evaluate Hb type (HbA, HbA2, HbC, HbSC, HbH)
Your pt is anemic. What are the possible causes?
Decreased RBC production
Increased RBC destruction
Blood loss
Sequestration of blood
What are the possible causes of decreased production of RBCs leading to anemia?
Malnutrition (Fe, B12, folate)
Infections (HIV, mycobacterial pneumonia, mononucleosis)
Inflammation (RA, SLE, other chronic infl. conditions)
Endocrine dysfunction (hypothyroidism, etc.)
Metabolic dysfunction (renal insufficiency, etc)
toxins (lead, drugs, EtOH, etc)
Bone marrow failure
Infiltration (fibrosis or tumor of bone marrow)
When testing for autoimmunity to determine the cause of hemolysis, what test is rapid and sensitive?
Direct Coomb’s
If your pt has hemolytic anemia and is Coomb’s negative, what else are you looking for?
microangiopathic or non-microangiopathic hemolytic anemias.
Your pt has microangiopathic hemolytic anemia. What are the potential causes of this?
** look or schistocytes! **
DIC, TTP, HUS, prosthetic heart valves, malignant hypertension
Your pt has non-microangiopathic hemolytic anemia. What are the potential causes of this?
congenital conditions:
membrane (hereditary spherocytosis), Hb (sickle cell, thals), enzyme dysfunction (G6PD deficiency)
acquired conditions:
infection, lead tox., paroxysmal nocturnal hemoglobinurea (PNH)
What is the most common hereditary enzyme defect leading to non-microangiopathic hemolytic anemia? What’s another important one that leads to non-microangiopathic hemolysis?
G6PD deficiency (cell cannot prevent oxidative damage, macrophages destroy cells in spleen); pyruvate kinase deficiency (no ATP, cell explodes from osmotic pressure)
Is pernicious anemia common among the causes of anemia?
No
Most anemias are microcytic, macrocytic, or normocytic?
85% are normocytic