Anemia - Diagnosis

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Normal percentages are highest in the very youngest individuals and decline as people age. They also vary by gender. The following are some examples of normal range:

• Newborns: 42 - 60%
• Children: 35 - 45%
• Adult males: 41 - 53%
• Adult women: 36 - 46%

Smokers, people at high altitudes, and those who are dehydrated tend to have higher than normal hematocrit levels. Those at greater risk for low hematocrit levels include pregnant women and patients with cirrhosis, heart failure, and splenomegaly.

Reticulocyte Count. Reticulocytes are immature red blood cells, and their count reflects the rate of red blood cell production. The upper normal limit is about 100,000/mL. A low count, when bleeding isn't the cause, suggests problems in production in the bone marrow. An abnormally high count indicates that the red blood cells are being destroyed in high numbers and indicates hemolytic anemia. New research suggests that the reticulocyte hemoglobin content (CHr) test may be more accurate than a standard hemoglobin test for detecting iron deficiency in infants. This test may help identify babies who are at risk for becoming anemic and help them get treated earlier.

Blood Morphology. A blood smear viewed under a microscope allows an expert to classify the blood by its color, size, and shape (its morphology ). Generally red blood cells are categorized as:

• Pale-colored (hypochromic) and abnormally small (microcytic)
• Normal colored and normal sized (normochromic, normocytic)
• Abnormally large (macrocytic)

The shape of the red blood cells, which can be distorted in many blood disorders, is also important in determining a diagnosis.

Diagnosing Iron Deficiency Anemia and its Causes

There are two steps in making a diagnosis in patients with symptoms of iron deficiency anemia:

• The first step is to determine if a person is actually deficient in iron.
• If iron stores are low, the second step is to diagnose the cause of the iron deficiencies, which will help determine treatment.

Determining if Iron Stores are Low. The following findings are important in determining that a person is iron deficient: