Laboratory tests for allied health fields are most commonly performed in the chemistry department. Within this department are subsections such as toxicology and radioimmunoassay. Computerized instruments used in this department are able to perform individualized tests or multiple tests from a single sample.
Serum is the most common chemistry specimen. Other specimens such as plasma, whole blood, urine and other body fluids are also tested.
Common Chemistry Tests:
Alanine aminotransferase (ALT): Associated with the liver. Marked elevations point to liver disease; used for monitoring liver treatment.
Alpha-fetoprotein (AFP): Associated with the liver. Increased levels are seen in hepatic carcinoma; elevation of AFP in prenatal screening indicates neural tube disorder.
Alkaline phosphatase (ALP: Associated with the liver or bone. Elevated levels may indicate biliary obstruction and bone disease.
Ammonia: Associated with the liver. Increased levels in blood indicate cirrhosis and hepatitis.
Amylase: Associated with the pancreas and liver. Increased levels of this enzyme diagnostic for acute pancreatitis; decreased levels are associated with liver disease, cholecystitis, and advanced fibrosis.
Aspartate amino transferase (AST): Associated with the liver or heart. Increase in enzyme indicates liver dysfunction; a significant increase may follow myocardial infraction.
Bilirubin: Associated with the liver. Increased levels in the blood stream may indicate red cell destruction and liver dysfunction.
Blood gases (ABG): Associated with the kidneys and lungs. This test measures pH, partial pressure of carbon dioxide, partial pressure of oxygen to evaluate the acid-base balance.
Serology and Immunology
Serology is the study of serum. Serology tests the body’s response to the presence of bacterial, viral, fungal, or parasitic diseases that can stimulate antigen-antibody reactions in a laboratory environment. Serologic tests are able to detect autoimmune reactions, in which autoantibodies produced by B lymphocytes attack normal cells. Testing is in several ways. Enzyme immunoassay (EIA), agglutination, complement fixation, or precipitation is used to determine the antibodies or antigens present as well as to assess its concentration.