Section 1: Anemia_Nonhemolytic Flashcards
CF of anemia
- Tiredness
- Fatigue
- Malaise
- Loss of energy
More severe anemia
- Short of breath
- Lightheadedness
- Confusion
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4877-4889). . Kindle Edition.
A craving for ice is a pointer to ——?
Iron deficiency anemia
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4877-4889). . Kindle Edition.
DD of anemia
- Hypoxia
- Carbon monoxide poisoning
- Methemoglobinemia
- schemic heart disease
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4877-4889). . Kindle Edition.
Physical exams for CCS for anemia
List the system to examine
- General appearance
- CV
- Chest
- Extremities
- HEENT
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4891-4902). . Kindle Edition.
Common PE findings in anemia
- Pallor
- Flow murmur described as I/ VI or II/ VI systolic murmur
- Pale conjunctiva
- Jaundice and scleral icterus (yellow eyes)
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4891-4902). . Kindle Edition.
Best initial diagnostic test for anemia
CBC with peripheral smear (pay special attention to the MCV/ MCHC)
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4891-4902). . Kindle Edition.
Additional tests in anemia after CBC and peripheral field
- Reticulocyte count
- Haptoglobin
- LDH
- Total and direct bilirubin
- TSH with T4
- B12/ folate levels
- Iron studies
- Urinalysis with microscopic analysis
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4891-4902). . Kindle Edition.
Classify anemia based on the MCV (mean corpuscular volume)
- Microcytic
- Normocytic
- Macrocytic
Classify anemia based on the MCHC
- Hypochromic
- Normochromic
- Hyperchromic
Likely diagnosis (microcytic anemia)
- Blood loss
- Elevated platelet count
Iron deficiency
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4908-4960). . Kindle Edition.
Likely diagnosis of microcytic anemia
- Rheumatoid arthritis
- End-stage renal disease
- Any chronic infectious, inflammatory, or connective tissue disease
Anemia of chronic disease
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4908-4960). . Kindle Edition.
Likely diagnosis of microcytic anemia:
- Very small MCV with few or no symptoms
- Target cells
Thalassemia
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4908-4960). . Kindle Edition.
Likely diagnosis of microcytic anemia
- Alcoholic
- Isoniazid
- Lead exposure
Sideroblastic anemia
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4908-4960). . Kindle Edition.
Iron deficiency anemia:
- Best initial diagnosis and findings
- Most accurate diagnostic test
- Best initial thearpy
Iron studies:
- Low ferritin
- High TIBC
- Low Fe
- Low Fe sat
- Elevated RDW (red blood cell distribution width)
Bone marrow biopsy (not necessary in CCS)
Oral ferrous sulfate
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4908-4960). . Kindle Edition.
Anemia of chronic disease:
- Best initial diagnosis and findings
- Most accurate diagnostic test
- Best initial thearpy
Iron studies:
- High ferritin
- Low TIBC
- Low Fe
- Normal or low Fe sat
Most accurate test will be diases specific or none
Treat the underlying disease
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4908-4960). . Kindle Edition.
Thalassemia:
- Best initial diagnosis and findings
- Most accurate diagnostic test
- Best initial thearpy
Iron studies:
- Normal
Hemoglobin Electrophoresis
- Beta: Elevated HgA2, HgF
- Alpha: Normal
No treatment
Alpha thalassemia is most accurately diagnosed by DNA sequencing
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4908-4960). . Kindle Edition.
Sideroblastic anemia:
- Best initial diagnosis and findings
- Most accurate diagnostic test
- Best initial thearpy
Iron studies:
- High Fe
Prussian blue stain
Minor: Prescribe pyridoxine replacement
Major: Remove the toxin exposure
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4908-4960). . Kindle Edition.
Microcytic anemia:
- Most important test
- Most accurate test
- Iron studies/ profile (Fe level, Fe saturation, ferritin, TIBC)
- Bone marrow biopsy
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4964-4987). . Kindle Edition.
True or False:
Only iron deficiency is associated with an elevated red cell distribution of width (RDW)
True
This is because the newer cells are progressively smaller and smaller; therefore, the red cell width changes over time
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4964-4987). . Kindle Edition.
A 62-year-old-man with a history of anemia from a bleeding peptic ulcer comes for evaluation. He is constipated and has black stool. His medications are omeprazole, oral ferrous sulfate, and occasional liquid antacids. What would you do next?
a. EGD
b. Colonoscopy
c. Guaiac testing/ hemoccult
d. Discontinue omeprazole
e. Increase the dose of ferrous sulfate
C. Oral ferrous sulfate can turn the stool black, but elemental iron such as this does not make the stool guaiac positive. Only the iron in hemoglobin or myoglobin can make the stool guaiac card positive.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4964-4987). . Kindle Edition.
A 68-year-old woman is found on routine CBC to have a hematocrit of 32 percent (normal 37– 42) and an MCV of 70 (normal 80– 100). Her stool is heme negative. What should you do next?
a. Colonoscopy
b. Sigmoidoscopy
c. Barium enema
d. Upper endoscopy
e. Two more stool tests now
f. Repeat the stool testing in a year
g. Capsule endoscopy
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kindle Locations 4964-4987). . Kindle Edition.
A. Colonoscopy is indicated in all patients > 50 simply as routine screening. Hence, in this case, the patient needs colonoscopy anyway, regardless of what the stool tests show. Another reason to go straight to colonoscopy is the presence of microcytic anemia. Unexplained microcytic anemia in a patient above 50 is most likely caused by colon cancer. Sigmoidoscopy will do nothing to evaluate the right side of the colon and would miss nearly 40 percent of cancers. No matter what a sigmoidoscopy showed, you would need to inspect the right side of the colon. Capsule endoscopy is done to evaluate bleeding when the upper and lower endoscopy are normal and the source of bleeding is likely to be in the small bowel.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 4988-5011). Kaplan Publishing. Kindle Edition.
True or False:
The only microcytic anemia with a high reticulocyte count is HgH
True
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 4988-5011). Kaplan Publishing. Kindle Edition.
A patient comes with end stage renal disease for evaluation of shortness of breath. After dialysis, he is found to have a hematocrit of 28 with an MCV of 68. Iron studies are performed. What do you expect to find? Iron Total Iron Binding Capacity Ferritin RDW
a. Iron:Low; TIBC:High; Ferritin: Low; RDW:High
b. Iron:Low; TIBC:Low; Ferritin:Normal; RDW:Normal
c. Iron:Normal; TIBC:Normal; Ferritin:Normal; RDW:Normal
d. Iron:High; TIBC:High; Ferritin:Normal; RDW:Normal
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 5007-5034). Kaplan Publishing. Kindle Edition.
C. The anemia of chronic disease, such as that found in patients with end stage renal disease, is associated with normal or increased amounts of iron in storage (ferritin/ TIBC) but the inability to process the iron into usable cells and hemoglobin. The only form of anemia of chronic disease that reliably responds to erythropoietin is caused by end stage renal disease.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 5007-5034). Kaplan Publishing. Kindle Edition.
True or False:
“Extravascular” hemolysis occurs in spleen and liver, so you cannot see it on the smear.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 5007-5034). Kaplan Publishing. Kindle Edition.
True
True or False:
Metfromin block B12 absorption
True
CF of B12 macrocytic anemia
- Fatigue and other features of anemia
- Peripheral neuropathy
- Glossitis (smooth tongue)
- Diarrhea
Neurological problems resolve with treatment if they have been present for a short duration of time
Folate deficiency does not cause neurological problems
Macrocytic anemia:
Best initial test
Most accurate test
CBC with peripheral blood smear
Serum level of B12 or Folate
Diagnostic tests for CCS in a case of macrocytic anemia
CBC with peripheral blood smear
Serum level of B12 or Folate
Serum Bilirubin
LDH
Reticulocyte
Oval cell will be visible on the peripheral smear as well
Up to 30 percent of those with B12 deficiency can have a normal B12 level, because transcobalamin is an acute phase reactant and any form of stress can cause its elevation.
If you suspect B12 deficiency, what test should be ordered?
Methylmalonic acid level
Homocysteine levels go up in both vitamin B12 deficiency and folate deficiency
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 5057-5067). Kaplan Publishing. Kindle Edition.
When asked, after finding a low B12 level or elevated methylmalonic acid level,
“What is the next best test to confirm the etiology of the B12 deficiency?”
.
Antiparietal cell antibodies and anti-intrinsic factor antibodies
Antiparietal cell antibodies and anti-intrinsic factor antibodies confirm pernicious anemia as the etiology of the B12 deficiency. Essentially, pernicious anemia is an allergy to parietal cells; it is a kind of autoimmune disorder against this part of the stomach.
Schilling’s test is an older, rarely done method of confirming the etiology and is not necessary if the antibodies are present.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 5057-5067). Kaplan Publishing. Kindle Edition.
B12 deficiency and folate deficiency are treated with replacement.
After B12 replacement therapy:
- What improves first?
- What follows after 1?
- What will improve last?
- True or False: there is low potassium after treating B12 deficiency!
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 5068-5080). Kaplan Publishing. Kindle Edition.
- Reticulocytes improve first
- The hypersegmented neutrophils improve
- Neurological abnormalities improve last
- True
Folate will correct the blood problems in B12 deficiency
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 5068-5080). Kaplan Publishing. Kindle Edition.