Tests
RDW (Red Cell Distribution Width)
A red cell distribution width (RDW) test measures how much the volume and size of your red blood cells (erythrocytes) varies.
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Tests
A red cell distribution width (RDW) test measures how much the volume and size of your red blood cells (erythrocytes) varies.
Tests
A red blood cell (RBC) count measures the number of red blood cells, also known as erythrocytes, in your blood. Red blood cells are made in your bone marrow, the spongy tissue inside your large bones. They contain hemoglobin, an iron-rich protein that carries oxygen from your lungs to every cell in your body. Your cells need oxygen to grow, reproduce, and make energy for you to function. An RBC count that is higher or lower than normal is often the first sign of an illness. So, the test may allow you to get treatment even before you have symptoms.
Tests
Red blood cell (RBC) indices measure your red blood cells' size, shape, and quality. Red blood cells are also known as erythrocytes. They are made in your bone marrow (the spongy tissue inside your large bones). They contain hemoglobin, an iron-rich protein in your red blood cells that carries oxygen from your lungs to every cell in your body. Your cells need oxygen to grow, reproduce, and make energy.
Tests
An RBC (red blood cell) antibody screen is a blood test that looks for RBC antibodies in your blood. These antibodies destroy red blood cells that are foreign (different from your own).
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This test measures the level of renin in your blood. Renin is an enzyme, a protein that speeds up certain chemical reactions in your body. It's made by your kidneys. When your blood pressure or sodium decreases or your potassium increases, your kidneys release renin. That's because renin also acts as a hormone (a chemical messenger in your bloodstream that controls the actions of certain cells or organs) to help control your blood pressure.
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RSV stands for respiratory syncytial virus. It is a viral infection that affects the respiratory tract. Your respiratory tract includes your lungs, nose, and throat. RSV testing checks a fluid sample from your nose to see if the virus is in your body and causing symptoms of a respiratory infection.
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A reticulocyte count (retic count) measures the number of reticulocytes in your blood. Reticulocytes are immature (still developing) red blood cells (RBCs). Your body makes reticulocytes in your bone marrow. Then it sends them into your blood, where they mature into red blood cells within one to two days. The main job of the red blood cells is to move oxygen from your lungs to every cell in your body.
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A rheumatoid factor (RF) test checks a sample of your blood for rheumatoid factor, a protein made by the immune system .
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This test measures the amount of salicylates in the blood. Salicylates are a type of drug found in many over-the-counter and prescription medicines. These can include:
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An SHBG blood test measures the level of a protein called sex hormone binding globulin (SHBG) in a sample of your blood. SHBG is made mostly in your liver. It binds (attaches) to sex hormones such as testosterone and estrogen and helps control how much of these hormones are active in your body.
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This test looks for smooth muscle antibodies (SMAs) in a sample of your blood. High levels of SMAs are usually a sign of a chronic (long-lasting) liver condition called autoimmune hepatitis .
Tests
A sodium blood test measures the amount of sodium in your blood. Sodium is a type of electrolyte . Electrolytes are minerals that have an electrical charge when they are dissolved in water or body fluids. You have electrolytes in your blood, urine (pee), tissues, and other body fluids. They help control the amount of fluid and the balance of acids and bases (pH balance) in your body. Sodium also helps your nerves and muscles work properly.