Blood tests can provide a wealth of information about your health. These diagnostic tools help in the determination of disease. Some diseases can change the number of certain types of blood cells, while others can destroy cells or change their shape, all effects that can be identified through blood testing. There are diseases which can affect how long it takes for your blood to form a clot. Some infections can affect your blood cells as well.
Complete Blood Count
The complete blood count (CBC) provides your physician with information about your white blood cells, red blood cells and platelets. It provides the total number of your white blood cells which fight infection. You have five types of white blood cells. The CBC provides your percentage for each type, referred to as the differential. It also provides information about your red blood cells (RBCs). A CBC gives the total number of red blood cells (RBCs) and lists the concentration of hemoglobin, a protein that carries oxygen. The CBC also includes the total number of platelets, the cells involved in clotting to prevent the loss of blood.
Reticulocyte Count
Blood cells are formed in the bone marrow. Reticulocytes are the young RBCs that are not yet mature, but have been released by the bone marrow to enter into your bloodstream. Daniel Ryan, M.D., professor of pathology and laboratory medicine at the University of Rochester Medical Center explains in "Williams Hematology," that the reticulocyte count is used to help determine if RBCs are being destroyed and whether bone marrow is functioning properly.
PT and PTT
PT stands for prothrombin time and PTT is the partial thromboplastin time. According to Diana Nicoll, M.D., Ph.D., associate dean of the University of California, both of these blood tests evaluate whether or not you can create blood clots within the normal amount of time.
ABO Typing
Ravindra Sarode, M.D., director of transfusion medicine and hemostasis laboratory at the University of Texas Southwestern Medical Center writes in "The Merck Manual for Healthcare Professionals," that ABO typing is the blood test that determines what type of blood you have. This is crucial in the event that you need a blood transfusion. If you receive the wrong blood type, your immune system will destroy the transfused blood. This can be a life-threatening condition.
Rh Typing
Rh typing identifies whether or not you have the Rh(D) antigen on your RBCs. Sarode explains that if you do not have this antigen (substance) on your RBCs, you are called Rh negative which means that, in cases where transfusion is needed, you will always need Rh-negative blood. If you have the Rh(D) antigen, you are Rh positive and can be transfused with Rh negative or Rh positive blood. This blood test also identifies the Rh type of a fetus and mother.
References
- "Pocket Guide to Diagnostic Tests"; Diana Nicoll, M.D., PhD, Stephen McPhee, M.D., Michael Pignone, M.D., Chuanyi Lu, M.D.; 2007
- The Merck Manual: Blood Collection
- "Williams Hematology"; Marshall Lichtman, M.D., Ernest Beutler, M.D. et al.; 2006
