Symptom Finder - Abnormal Laboratory Values
Abnormal Laboratory Values
As with functional changes, the principal basic sciences used to develop the differential diagnosis of abnormal laboratory values will be physiology and biochemistry.
For example, the clinician has just received a complete blood cell count showing a reduction of hemoglobin and hematocrit. Using physiology, he
or she can recall that anemia may develop from a decreased intake or absorption of iron, B12, or folic acid, a decreased production of red cells in
the bone marrow, or increased destruction of red cells in the spleen or blood circulation. Now, the clinician can prepare a simple list of
possibilities using common etiologies as follows:
1. Decreased intake: iron deficiency anemia, starvation, folic acid deficiency
2. Decreased absorption: pernicious anemia, malabsorption syndrome
3. Decreased production: aplastic anemia, myelophthisic anemia
4. Increased destruction: hemolytic anemia, DIC, malaria, and so forth.
The list of possibilities can be expanded by taking this sign to the
second and third steps, as demonstrated above.
As with functional changes, the principal basic sciences used to develop the differential diagnosis of abnormal laboratory values will be physiology and biochemistry.
For example, the clinician has just received a complete blood cell count showing a reduction of hemoglobin and hematocrit. Using physiology, he
or she can recall that anemia may develop from a decreased intake or absorption of iron, B12, or folic acid, a decreased production of red cells in
the bone marrow, or increased destruction of red cells in the spleen or blood circulation. Now, the clinician can prepare a simple list of
possibilities using common etiologies as follows:
1. Decreased intake: iron deficiency anemia, starvation, folic acid deficiency
2. Decreased absorption: pernicious anemia, malabsorption syndrome
3. Decreased production: aplastic anemia, myelophthisic anemia
4. Increased destruction: hemolytic anemia, DIC, malaria, and so forth.
The list of possibilities can be expanded by taking this sign to the
second and third steps, as demonstrated above.