A genetic test checks the DNA of your cells. It can find changes in your genes or chromosomes that may cause a genetic illness. The results may tell you about your ancestry, your health, or your risk for certain diseases. Testing can be done on a single gene, selected genes, or all of your genes (your genome). The test...

Discusses blood glucose tests used to diagnose diabetes and prediabetes. Covers types of tests, including fasting blood sugar, 2-hour postprandial blood sugar, random blood sugar, and oral glucose tolerance. Discusses how to prepare and what results mean.

A test for calcium in urine is a 24-hour test that checks the amount of calcium that is passed from the body in the urine. Calcium is the most common mineral in the body and one of the most important. The body needs it to build and fix bones and teeth, help nerves work, make muscles squeeze together, help blood clot...

Creatinine and creatinine clearance tests measure the level of the waste product creatinine (say "kree-AT-uh-neen") in your blood and urine. These tests tell how well your kidneys are working. Another substance, creatine (say "KREE-uh-teen"), is formed when food is changed into energy through a process called...

The phosphate urine test measures the amount of phosphate in a sample of urine collected over 24 hours (24-hour urine test). Phosphate is a charged particle (ion) that contains the mineral phosphorus. The body needs phosphorus to build and repair bones and teeth, help nerves function, and make muscles contract. Most...

Thyroid antibody tests measure the levels of antibodies that can destroy thyroid tissue or make the cells produce thyroid hormones. They are blood tests. Antibodies that destroy thyroid tissue can lead to hypothyroidism (underactive thyroid). Antibodies that make the cells produce thyroid hormone can lead to...

An arterial blood gases (ABG) test measures the acidity ( pH) and the levels of oxygen and carbon dioxide in the blood from an artery. This test is used to find out how well your lungs are able to move oxygen into the blood and remove carbon dioxide from the blood. As blood passes through your lungs, oxygen moves into...

Covers why and how parathyroid hormone tests are done. Covers what possible results might mean. Includes info on what might affect the test.

Covers screening tests, diagnostic tests, and medical exams used to find a disease or determine risk for certain health problems. Covers well-child visits. Includes links to info on routine tests for men, for women, and at various stages of life.

Describes colonoscopy, a screening test that examines the lining of the large intestine. Explains that the test is done to look for polyps in the colon or rectum and to check for colorectal cancer. Discusses preparing for the test and how it is done.

This test measures the amount of lead in a person's blood. Lead is a poisonous (toxic) metal that can damage the brain and other parts of the body. A lead test may be done on blood taken from the vein, a finger (finger stick), or the heel (heel stick). A person can be exposed to lead: By eating or drinking...

A chloride test measures the level of chloride in your blood or urine. Chloride is one of the most important electrolytes in the blood. It helps keep the amount of fluid inside and outside of your cells in balance. It also helps maintain proper blood volume, blood pressure, and pH of your body fluids. Tests for sodium...

Discusses blood test to check level of potassium (K) in blood. Includes info on what affects potassium levels in the body such as kidney function, blood pH, and hormones. Explains how and why test is done. Covers what results mean.

Discusses test to check level of potassium (K) in urine. Includes info on what affects potassium levels in the body such as kidney function, blood pH, and hormones. Explains how and why test is done. Covers what results mean.

Discusses blood test used to check for thyroid gland problems. Explains how TSH causes thyroid gland to make hormones that help control metabolism. Covers how it is done and test results.

The sedimentation rate (sed rate) blood test measures how quickly red blood cells (erythrocytes) settle in a test tube in one hour. The more red cells that fall to the bottom of the test tube in one hour, the higher the sed rate. When inflammation is present in the body, certain proteins cause red blood cells to stick...

Discusses C-peptide test, used to tell the difference between type 1 and type 2 diabetes, find the cause of hypoglycemia, or check whether a pancreas tumor (insulinoma) was completely removed. Discusses how the test is done and how to prepare for it.

An alpha-fetoprotein (AFP) blood test checks the level of AFP in a pregnant woman's blood. AFP is a substance made in the liver of an unborn baby (fetus). The amount of AFP in the blood of a pregnant woman can help see whether the baby may have such problems as spina bifida and anencephaly. An AFP test can also be done...

Discusses cancer antigen 125 (CA-125) test that can help show if some types of cancer are present. Covers its use to check how well treatment for ovarian cancer is working or to see if ovarian cancer has returned. Covers possible test results.

Discusses blood test to check the different types of hemoglobin in the blood. Covers how some diseases, such as sickle cell disease, aplastic anemia, and leukemia, have abnormal types of hemoglobin. Discusses possible test results.

Looks at assessments done to discover problems like depression, schizophrenia, Alzheimer's disease, learning disabilities, or obsessive-compulsive disorder. Covers what is done, including an interview, physical exam, lab tests, and written or verbal tests.

Includes tips to comfort a child before a medical test. Offers tips based on age, from newborns through the teen years.

This test for Tay-Sachs disease measures the amount of an enzyme called hexosaminidase A (Hex A) in the blood. Hex A breaks down fatty substances in the brain and nerves. Tay-Sachs is an inherited disease in which the body can't break down fatty substances as it should, so the fatty substances collect in the nerve cells...

What are outpatient services? Outpatient services are medical procedures or tests that can be done in a medical center without an overnight stay. Many procedures and tests can be done in a few hours. Outpatient services include: Wellness and prevention, such as counseling and weight-loss programs. Diagnosis, such as lab...

Tests for erection problems can help you find out why you can't have or maintain an erection. This problem is called erectile dysfunction, or impotence. It's a common problem. Most erection problems are caused by a mix of blood vessel, nerve, or psychological issues. To find the cause, your doctor will first ask about...