What is a complete blood count (CBC) measuring?
During a CBC, a lab technician will look at your blood under a microscope. Using a special machine to help them analyze the blood, they take a count of the different blood parts. Each cell type, or – in the case of hematocrit, each measurement – can help hint at what is going on in the body. This can potentially diagnose lupus, or, just as importantly, gauge overall health. The cell types counted in the test are:
Red blood cells
Red blood cells carry oxygen throughout the body. For most people, these important cells are circular with a small dimple in the center. However, for people carrying the sickle-cell gene, a few red blood cells have a different structure that resembles a sickle or crescent moon shape. These miss-formed red blood cells do not carry oxygen as effectively and can also clog vessels in the bloodstream resulting in pain and organ damage.
These unusual blood cells are the cause of Sickle Cell Anemia, a condition that can co-occur in people with lupus. The people at highest risk for developing sickle-cell (people of African, Asian, Central American, South American, Middle Eastern, Indian, and Mediterranean descent) also have an increased risk of lupus. Lupus itself can also cause low levels of red blood cells.
Fewer red blood cells means less oxygen is being transported to the body. As cells and organs are starved for oxygen, fatigue and brain fog can happen. Anemia also makes organs more susceptible to damage.
Exactly what causes this type of anemia isn’t always clear in people with lupus. But, catching it early allows people with lupus to pursue treatment options to prevent damage and relieve symptoms. You can read more about lupus-related anemia here.
Hemoglobin is actually a part of the red blood cell. In fact, hemoglobin is the structure that actually carries the oxygen through the bloodstream. Measuring both hemoglobin levels and counting red blood cells helps doctors better diagnose anemia.
Normal levels fall in the range of 11.5 to 15.0 grams per deciliter of blood.