Anemia Flashcards
What is anemia?
- Decreased Hgb and RBCs =
2. Decrease in oxygen carrying capacity of blood
What causes anemia?
- Decreased RBC productions
- Increased RBC loss
- Increased RBC destruction
- Decreased RBC productions
- Increased RBC loss
- Increased RBC destruction
- Hgb < 13 g/dL for men
- Hgb < 12 g/dL for women
- “Sign of disease”
What is the 2nd most prevalent and costly public health issue?
Anemia
How can you monitor or screen for anemia?
With NO chronic conditions check CBC every 5 years, if Hgb 11-12 g/dL consider further workup
With chronic conditions check CBC yearly
What is the clinical presentation of acute anemia?
- Tachycardia
- Angina
- Lightheadedness
- SOB
What is the clinical presentation of chronic anemia?
- Fatigue
- Weakness
- Headache
- Dizziness
- Pallor
- Sensitivity to the cold
What is the normal clarification of RBC size/Hgb content?
Normochronic and normocytic
Define Macrocytic
an abnormally large red blood cell
Define Microcytic
an abnormally small red blood cell
Define Hyperchromic
the red blood cells have more hemoglobin than normal
Define Hypochromic
the red blood cells have less hemoglobin than normal
What is the initial evaluation of anemia?
- CBC-Complete blood count (RBC indices)
- Reticulocyte Index
- Supporting labs (iron, folate, B12, etc.)
- Fecal occult blood stool cards
What is hemoglobin and what are the normal values?
- Estimates oxygen carrying capacity
- Men: < 13 g/dL
- Women: <12 g/dL
Where is hemoglobin made?
in RBCs
What happens with Hgb in anemia?
- Decreased Hgb per RBC
2. Decreased number of RBCs
What is hematocrit?
The % of RBCs in unit volume of whole blood
usually 3x the Hgb value
What happens to happens to hematocrit in anemia?
Decreased (increase in plasma volume)
What is the red blood cell count?
- Number of RBCs per unit of blood (millions/mcg)
What is the lifespan of a RBC?
120 days
What happens to RBCs in anemia?
Decreases
In what special populations do normal values vary?
- High altitude
- Smokers
- Elderly
What are the three RBC indices?
- MCV
- MCH
- MCHC
What are special facts about RBC indices?
- Describe size and Hgb content or RBCs
2. Do not express variation between cells
What is MCV?
Mean Cell Volume
What happens to MCV in macrocytic RBCs?
Increases
ALSO, folic acid and B12 deficient
What happens to MCV in microcytic RBCs?
Decreases
ALSO, Iron deficiency
What is Mean Cell Hemoglobin (MCH)?
The amount of Hgb in a RBC
What are false elevations of MCV referred to as?
Reticulocytosis
What happens to MCH in macrocytosis? microcytosis?
- Increases
- Decreases
* You actually can’t distinguish between microcytosis and hypochromia*
What is the Mean Cell Hemoglobin Concentration (MCHC)?
Weight of Hgb per volume of cells (concentration)
-Independent of cell size
What occurs when a patient has a low MCHC and MCH?
Hypochromia
What occurs when there is normal MCHC and a decreased MCH?
Microcytosis
What is a reticulocyte?
young red blood cell
-indicates new RBC productions
What happens when total reticulocyte count is low? High?
- problem with bone marrow production
2. increased erythropoietic response to hemolysis or blood loss
What is the RBC distribution width?
Variation in RBC size
-Increased % = greater variation in size
This is useful for Dx of mixed anemia
What is meant by ‘serum iron’?
Concentration of iron bound to transferrin
Transferrin = binds and transports iron (normally 1/3)
What is the total iron binding capacity (TIBC)?
Measures the iron binding capacity of transferrin
DOES NOT FLUCTUATE
What does it mean when a patient has high TIBC and low serum iron?
Iron deficiency
What does it mean when a patient has low TIBC and low serum iron?
Anemia of chronic disease
What is transferrin saturation?
indicates the extent to which iron binding sites on transferrin are vacant
Serum Iron / TIBC X 100 = % ~33%
What is ferritin?
storage iron
it is proportional to total iron stores in the body
What does it mean when a patient has low ferritin?
Virtually diagnostic for IDA–chronic disease
What do low levels of folic acid and vitamin B-12 mean?
Vitamin deficiencies
What is important about homocysteine?
Folic acid and b-12 are needed to convert homocysteine to menthinoine
If there are high levels of homocysteine there may be vitamin deficiencies
What is methylmalonic acid (MMA)?
Vitamin B-12 is needed to convert MMA to succinyl Co-A
If there is an increase in urinary secretion of MMA usually before there is a decrease in serum b-12
What is erythropoietin?
it stimulates RBC production and maturation
increases 100 to 1000 fold during hypoxia or anemia
What are the three reasons iron is important?
- Transports O2 to tissue as part of Hgb
- Cell’s energy metabolism
- Facilitates O2 use and storage in muscles
What causes IDA-the most common nutritional deficiency and type of anemia?
- Inadequate dietary intake (3rd world)
- Inadequate absorption (Gastrectomy)
- Increased Iron needs (blood donations)
- Blood loss (GI tract)
- Other chronic illnesses (malabsorption)
What is the clinical presentation of IDA?
Don’t appear until Hgb <8-9
- Glossal pain
- Decreased salivary flow
- Pica/parophagia
- Psychomotor/mental devalopment
- “spoon” shaped nails
- Guaiac stool