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Learn About Tests

Your health care provider may order lab tests as part of your normal wellness visit to monitor a disease or help diagnose an illness. They will explain the reason or purpose for the lab work as well as any specific instructions to follow.
There are too many to list individually, but these are the most commonly ordered lab tests:

Antinuclear Antibody (ANA): Looks for evidence of autoimmune diseases such as lupus or rheumatoid arthritis. Sample collection involves drawing blood.

Complete Blood Count (CBC): Evaluates cells that circulate in the blood. A CBC screens for, diagnoses, or monitors a variety of diseases and conditions that affect blood cells, such as anemia, infection, inflammation, bleeding disorder or cancer. Sample collection involves drawing blood.

Comprehensive Metabolic Panel (CMP): Measures 14 chemicals in the blood including sugar/glucose level, cholesterol, electrolyte and fluid balance, kidney function, and liver function. Sample collection involves drawing blood.

COVID Antibody: Detects antibodies produced by the body’s immune system in response to SARS-Cov-2 from a blood sample. COVID-19 serology tests can determine a prior infection.  However, antibody tests are not the preferred tests to diagnose current infections. Antibodies normally show up one to two weeks after first symptoms.

COVID PCR (SARS-CoV-2 polymerase chain reaction): A respiratory test that detects the virus’ RNA. The PCR test is the “gold standard” test for diagnosing an active COVID-19 infection due to its reliability and accuracy.
COVID Rapid Antigen: Detects the viral proteins of SARS-CoV-2 through respiratory samples to determine an active infection. Antigen tests can provide results in minutes and involve a simpler process. However, they are not as sensitive as PCR tests; therefore, negative results do not rule out infection.
Erythrocyte Sedimentation Rate (ESR): Measures the rate at which red blood cells settle at the bottom of a test tube over a period of one hour. The purpose is to identify inflammation (swelling). Sample collection involves drawing blood.

Some (not all) lab tests require “fasting” for 8-12 hours before testing. Fasting involves not eating or drinking anything (except water). Because nutrients from food and drinks move into the bloodstream, a test given after fasting will show the body’s natural levels of sugar, cholesterol, etc.

Platelet Count (can be a single test or part of a CBC): Determines the number of platelets in a sample of blood. Platelets are tiny parts of cells essential for normal blood clotting. This test is used to diagnose or monitor a bleeding disorder or bone marrow disease. Sample collection involves drawing blood.

Urinalysis: A test of your urine. It detects and manages a wide range of conditions, such as urinary tract infections, kidney disease and diabetes. A urinalysis involves checking the appearance, concentration and content of urine. Sample collection involves collecting one to two ounces of urine in a clean container.

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