This test looks for signs in your blood that you have the Epstein-Barr virus, the virus that causes mono.

This test looks for antibodies to 3 diseases: measles, mumps, and rubella.

This test measures the levels of Helicobacter pylori antibodies in your blood. The test can help find out whether your peptic ulcers are caused by these bacteria.

This test finds out if you have low levels of a particular enzyme that can cause hemolytic anemia.

This test measures the level of free T4 in your blood. It helps your health care provider know how well your thyroid is working.

This test looks for antibodies to a parasite that causes the disease amebiasis. This disease is more common in tropical countries with poor sanitation.

This test looks at the number and size of various blood cells to help judge your overall health or to diagnose a range of illnesses, from anemia to infections.

This test measures the amount of a protein called C4 in your blood. You may need this test if your doctor suspects that you have an autoimmune disease.

This test measures the amount of C3 proteins in your blood. C3 proteins are part of your immune system. This test can help diagnose lupus.

A sweat chloride test is used to diagnose cystic fibrosis, a disease that causes mucus to build up in the lungs and other organs.