EXAM #1: MICROCYTIC ANEMIA Flashcards
What is the most important point to remember about anemia?
Anemia is NOT a concluding diagnosis; it is a manifestation of disease
What is the definition of anemia?
Decreased RBC resulting in decreased oxygen carrying capacity
What are the common symptoms of anemia?
- Fatigue
- Dyspnea
- Weakness
What is the normal MCV of RBCs?
80-100 fL
What is the definition of microcytic anemia?
Less than 80 fl MCV
What is the rule of thumb for determining the size of a RBC on PBS?
- Lymphocyte nucleus
- Central pallor is roughly 1/3 of the RBC width
What are the hallmark features of microcytosis on PBS?
- Microcytic
- Hypochromic
What is a normal Hb for men?
14-17 g/dL
What is a normal Hb for women?
12-15 g/dL
What is a normal Hct in men?
42-50%
What is a normal Hct in women?
36-44%
What is the normal MCH?
Mean Corpusucular Hb
30-34pg
What is the normal MCHC?
Mean Corpusucular Hb Concentration
30-36%
What is the normal RDW?
Red Cell Distribution Width
13-15%
Note that the smaller the RDW, the more UNIFORM the size
What are the three causes of iron deficiency?
1) Inadequate absorption
2) Inadequate utilization
3) Excessive loss****
*****This is the most common cause
How much iron can be absorbed per day?
1-3mg
Where in the body is iron absorbed?
First and second parts of the duodenum
What is the difference between ferrous and ferric iron?
Fe++= ferrous Fe+++= ferric
What form of iron is most efficiently absorbed?
Heme iron
Are plants a good source of iron?
NO
- Low in iron to begin with
- Most is Fe+++
What transporter is important for the absorption of Fe++?
DMT-1
Divalent Metal Transporter
What happens to Fe++ once it is absorbed into the enterocyte?
Binds ferretin
How does iron/ferretin leave the enterocyte?
Ferroportin transporter
How is iron transported in the blood?
Plasma transferrin i.e. carrier protein
What blocks the ferroportin transporter?
Hepcidin (made in the liver)