Anemias Flashcards
Microcytic Anemias
Low MCV.
- Thalassemia
- Iron Deficiency
- Chronic Disease
- Sideroblastic Anemia
Whats the most common cause of iron deficiency anemia in the US?
Blood loss: either occult or acute.
- Generally GI
Average iron storage in adult man?
10mg/kg
Usual anemia presenting symptoms
Weakness, HA, Irritability, fatigue, exercise intolerance.
Many patients are asymptomatic
Pica
Cravings for food not fit for consumption. Dirt, paper, ice.
Pagophagia
Pica for ice. Considered quite specific for the iron deficiency state.
Gold standard for diagnosing iron deficiency.
Low serum ferritin (iron stores).
Serum iron: reduced
Total iron binding capacity: increased
Transferrin sat: low
RDW
Measures anesiocytosis
Test measuring the variation of size in red blood cells.
Microcytic anemia with low or normal RDW = ?
Chronic disease or thalassemia
Microcytic anemia with high RDW = ?
Iron deficiency anemia.
Anemia of chronic disease
Occurs in the setting of chronic inflammatory diseases.
EPO is low, serum iron is reduced.
ferritin is high(ddx from IDA)
usually normocytic, can be micro
Diseases than are commonly associated with ACD?
RA, SLE
HIV, TB
Carcinomas, lymphomas, leukemias
Megaloblastic Macrocytic Anemias
Abnormalities in DNA metabolism.
- B12 and Folate deficiency
- Drug side-effects
Absorption of B12 depends on these 5 things.
Adequate dietary intake Acid-pepsin in stomach Intrinsic factor Pancreatic proteases Functional ileum
Total body stores of cobalamin
The average stores of B12 are 2 - 5 milligrams
Pernicious Anemia
Autoimmune disease where parietal cells fail to release intrinsic factor in the stomach.
Lab results that ddx B12 from folate deficiency?
Elevated homocysteine (HC) AND Methylmalonic acid (MMA). Folate is just elevated HC
B12 deficiency tx
1000 mg B12 daily for a week, weekly for a month, monthly for life.
Most common cause of folate deficiency?
Nutritional due to poor diet and or alcoholism.
Non-megaloblastic macrocytic anemias?
Alcoholism Liver disease Aplastic anemia drug-induced pregnancy myeloma hypothyroidism
DDx for normocytic anemia
NORMAL SIZE HEM
Anemia of chronic renal failure.
different from chronic disease anemia. Much more severe.
Give EPO!
Mixed anemia
Order peripheral smear because many different cells. High RDW (many different sized cells), but MCV may be normal because the AVERAGE is in the normal range.
Reticulocyte count
Usually make up about 1% (stain blue)
Usually reticulocytes circulate in blood for one day before maturing.
Elevated count shows that bone marrow is responding to anemia and producing more cells.
3 areas where reticulocyte count is appreciated
Acute blood loss
Hemolytic anemia
Response to iron, B12, folate replacement
Anemia of acute blood loss
Source is usually quite clear
Generally takes 24 hours for Hgb to drop.
Reticulocytosis may result in mild macrocytic anemia.
Which test cal determine of a hemolytic anemia is immune?
Direct Coomb’s Test. Perform once you know the anemia is hemolytic.
Lab tests for hemolysis
Decreased Haptoglobin: bound with damages cells
Elevated D.Bili: porphyrin concerted to Bili
Elevated Lactate dehydrogenase (LDH): released from hemolysed RBC’s
HUS
Hemolytic urea syndrome. Cause by E-coli. Generally happens in kids and causes kidney failure.
Heriditary Hemochromatosis
Excess Iron.
Harrison’s disease.
Iron is deposited in many tissues and damages them.
What cells go with lead?
Stippling.
What does iron in tissues produce?
Hydrogen peroxide is converted to free radical ions. Can cause cancers, cardiac toxicity and many other factors
Hemochromatosis liver pathology
Usually first organ affected
Hepatomegaly present in 95%
Most common cause of death in treated pt’s.
Hemochromatosis Cardiac Pathology
Presenting in 15% of patients.
Mostly CHF and arrhythmias.
Hemochromatosis Pancreatic Pathology
Causes diabetes in 65% of patients
Generally have family hx of diabetes
Hemochromatosis Skin Pathology
Excessive skin pigmentation present in 90% of symptomatic pt’s.
Metallic hue
Hemochromatosis Pituitary pathology
Hypogonadism
Decreased libido, no period, manboobs
Hemochromatosis Joint pathology
Arthritic changes in 25 - 50% of pts
Often starts in hands
Pseudogout can occur
Hemochromatosis Lab Dx
Transferrin > 50%
Elevated serum ferritin
DNA testing
Hemochromatosis Tx
Phlebotomy
Take off blood volume, removes iron as well.