A CBC is the oldest blood analysis and currently the most commonly performed blood test.

It consists of a combination of tests which analyze the ceIlular make up of the blood. Some specific analyses of the CBC are as follows:

Hematocrit

The hematocrit represents the percentage of the blood volume which is comprised by red blood cells. If forty percent of the blood consists of red blood cells then the hematocrit is 40 volumes percent. A low hematocrit is a sign of anemia. Such anemia may be from nutritional factors, blood loss (bleeding) or other disease processes.

Hemoglobin

Hemoglobin makes up about 1/3 of all red blood cells. As such, it is directly proportional to the hematocrit. Hemoglobin is the chemical which allows blood to carry oxygen from the lungs. Iron is important in the chemical structure of hemoglobin. A low hemoglobin also represents anemia.

White Blood Count

White blood cells are a normal component of blood. Their primary function is as a defense against infections. An elevated white blood cell count may be a sign of infection. Some viral infections may lower the white blood count. There are 5 different types of white blood cells. Increases or decreases in these cells may indicate particular medical conditions.

Platelets

Blood platelets are a component of blood which is important in blood clotting (to stop bleeding). Platelets act by "sticking" to each other and "clotting" the bleeding site. Aspirin affects the clotting of blood by decreasing the effectiveness of platelets.

Diabetes is a disease caused by elevated levels of glucose in the blood serum. Insulin, a hormone manufactured in the pancreas normally functions to regulate the amount of glucose in the blood. When there is a deficiency of insulin, glucose rises and diabetes results.

Criteria for diagnosing diabetes include a random glucose greater than 200 or a fasting glucose greater than 125. Another test useful in diabetes is hemoglobin A1c. (HbA1c or glycohemoglobin). HbA1c is often used to indicate how well a diabetic or pre-diabetic’s glucose is controlled. This test measures a chemical which is a reflection of the average glucose levels in the blood over a period of 2 -3 months. A typical normal value for HbA1c is less than 5, while the goal of therapy in treating diabetes is often a HbA1c of less that 7, diabetes with a HbA1c greater than 8 must revaluate how their diabetes has been treated.