Antiphospholipid Antibody

This test checks for antibodies that may be found in people with abnormal blood clots or autoimmune diseases.

Antinuclear Antibody

This blood test is done to help your doctor diagnose a type of illness called an autoimmune disease.

Antimyocardial Antibody

This test checks the level of a certain antibody in your blood that can indicate heart damage. The antibodies show up before symptoms appear.

Antidiuretic Hormone

This test measures the amount of antidiuretic hormone (ADH) in your blood. ADH regulates your body's balance of water.

Anion Gap (Blood)

This test looks at electrically charged particles in your blood to help your doctor diagnose acid-base imbalances.

Anaerobic Culture

This test looks for certain bacteria in a wound or an infection in a fluid sample. These bacteria are called anaerobic because they don’t need oxygen to grow.

Amphetamine Screen (Blood)

This test measures the amount of a drug called amphetamine in your blood. The test is most often used to screen for drug abuse.