Description of Laboratory Tests

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Glossary/Vocabulary

Acetylcolinsterase/colinsterase - Measures the amount of these enzymes present in the body. "Decreased values indicate interference with the enzyme, usually as a result of organic phosphate poisoning. Colinsterase may also be decreased during pregnancy and with cancer, liver disease and certain skin conditions." Enzyme levels are rarely high, except in the presence of kidney disease and hyperthyroidism.-

Normal Values - > 0.5 pH units per hour-

When Performed - "When a variety of symptoms that result from excessive parasympathetic nervous system activity are observed (as described above), especially after possible exposure to insecticide; in certain skin, liver, and kidney diseases.-

Symptoms/Functions - Acetylcolinsterase/colinsterase are enzymes that control the body’s "involuntary processes that transmit nerve impulses to the heart, gastrointestinal tract, tear ducts, etc. When these processes are reduced or interfered with - either by disease or by inhalation, ingestion, or skin contact with organic phosphate insecticide such as malathion - the patient has increased parasympathetic nervous system activity. Symptoms include increased stomach acidity, increased intestinal motility, erratic pulse and heart rate, difficulty in breathing, increased sweating, salivation, and watering of the eyes" and pupil constriction. "Severe reactions include headaches, muscle twitching, convulsions, and diarrhea."-

 

Glucose 6-phosphate dehydrogenase (G6PD) - Measures the amount of the Glucose 6-phosphate dehydrogenase enzyme which is found in red blood cells.-

Normal Values - 120 - 280 units/billion cells-

When Performed - "In undiagnosed hemolytic anemia; before administration of antimalarial drugs, sulfanomides, and nitrofurans."-

Symptoms/Functions - "In people with a deficiency of this enzyme (an inherited condition), red blood cells are no longer protected from oxidation, causing hemolysis (destruction of red blood cells and subsequent separation of hemoglobin), which can lead to anemia. The deficiency is more frequent in Blacks, Orientals, and Caucasians from the Mediterranean area, and more serious in men than women." -

"Glucose 6-phosphate dehydrogenase deficiency, while not usually serious or chronic, can sometimes be fatal. It does not show itself until the patient ingests drugs or foods that precipitate the hemolytic anemia, which can then cause hemoglobinurea, jaundice, fever, and renal failure. Some of those drugs are Primaquine (for malaria, aspirin, sulfa products, nitrofurans, vitamin C, certain antibiotics, some worm medicines, inhalation of naphthalene (moth repellent), and eating fava beans - but only in people born with a G6PD deficiency."-

 

Hematocrit - "Shows the percentage of blood cells (mostly red blood cells) comprising the total blood volume. Low hematocrit readings (decreased percentage of total cells) are found in red blood cell anemias, immediately after hemorrhage, and whenever there is excessive fluid intake. High hematocrit readings are found in severe dehydration and polycythemia, angina, and after surgery, trauma, or burns."-

Normal Values - 40% - 55% (slightly lower in women)-

When Performed - "In diagnostic screening for anemias and dehydration; to follow the course of therapy for anemias and hemorrhage. An abnormal result should be followed by more appropriate tests."-

 

Hemoglobin - Measures the amount of hemoglobin in the blood. Hemoglobin levels are increased "when red blood cells are suddenly damaged or destroyed, as with sickle cell disease or the Rh anemia of infancy. Polycythemia (a disease characterized by excessive red blood cells) may show increased hemoglobin. Hemoglobin values are decreased in most forms of anemia, especially those associated with iron deficiency. Hemoglobin is decreased in leukemia, after hemorrhage, and in pregnancy."-

Normal Values - men 14-18 g per 100 ml; women 12-15 g per 100 ml-

When Performed - "Primarily when there is a suspicion of anemia; to aid in the diagnosis of many inherited conditions (such as sickle cell anemia); to distinguish certain poisonings from disease; an indication of how much blood has been lost after injury or surgery."-

Symtoms/Functions - "Hemoglobin is an iron protein substance manufactured inside newly forming red blood cells and stored for the life of the cells. Its task is to pick up oxygen as the red blood cells pass through the lungs and deliver that oxygen to tissue cells throughout the body."-

 

Hemolysis/Haptoglobin - Measures the amount of haptoglobin in the body. "Reduced levels of haptoglobin indicate hemolysis. Decreased values of haptoglobin also are also found in liver disease and with infectious mononucleosis. Certain severe infections, tissue damage such as with heart attack, and cancers cause increased haptoglobin levels."-

Normal Values - 50-100 mg per 100 ml serum-

When Performed - "When anemia is present, especially when it is thought to be from an inherited condition such as thalassemia (Mediterranean or Cooley’s anemia) or from Rh problems; when it is suspected that certain environmental factors (chemicals, drugs, or physical injury ) are causing anemia; in severe infections; with liver disease."-

Sympoms/Functions - Haptoglobin is a blood globulin. Hemolysis means "increased breakdown of red blood cells and the liberation of Hemoglobin into the plasma. When hemolysis occurs, the red blood cells do not last as long as they should, and this usually (but not always) results in anemia. -

 

Immunoglobulin (including Milk IgE) - Measures the amount of immunoglobulin in the blood. "Immunoglobulins are increased as a result of infection, allergy, and various autoimmune conditions in which the body in essence turns on itself and causes illness. After cancer surgery, an increase in immunoglobulins is usually a good sign. Immunoglobulins may be decreased with certain leukemias, cancers, and other conditions where immunity is lacking."-

Normal Values - in mg per 100 ml-

IgG:
IgA:
IgM:
IgE:
IgD:
500-2000 -
50-400-
50-200-
0.01-0.1-
0.5-5-

When Performed - "When excessive gamma globulins are found, as with leukemias, certain cancers, kidney problems, parasitic infections, and chronic infections; after surgery for cancer as a guide to progress; when multiple sclerosis is suspected."-

Symptoms/Functions -"Immunoglobulins (Ig) are the blood protein antibody particles (gamma globulins) of the body. They react with, protect against, and help destroy antigens, which can cause illness. An antigen may be a microorganism (bacteria, virus, fungus), a chemical, or a toxin given off by an invading microorganism. Usually antibodies are specific; that is, they react only to a particular disease-causing substance."-

"Five major immunoglobulins can be tested for in the blood:-

IgG - is the most abundant type, responds to any foreign body invasion and can cause Rh anemia problems.-

IgA - protects against viral and bacterial infections and can cause transfusion reactions.-

IgM - is another response to infection; it also reacts to arthritis.-

IgE - is involved in allergic reactions such as asthma, hay fever, and skin rashes.-

IgD - can be isolated, but its action is still not understood.-

 

Magnesium - Measures the amount of magnesium in the blood. "Lower than normal values are found with parathyroid, thyroid, and adrenal gland hyperactivity, and with malnutrition, chronic alcoholism, pancreatitis, and diuretic therapy. Higher than normal values are found with dehydration and with inactive adrenal glands; after a heart attack."-

Normal Values - 1.5-2.5 mEq per liter; 2 mg per 100 ml-

When Performed - "Whenever patients exhibit symptoms such as twitching and quivering muscles, irritability, and weakness. It is also used to determine whether these symptoms are caused by lowered Calcium levels rather than by lower magnesium levels."-

Symptoms/Functions - "Magnesium is found in all cells and its active in many biochemical processes, particularly in enzyme reactions. Magnesium is important to the regulation of the body’s calcium supply and usage."-

 

Platelet Count - Measures the amount of platelets in the blood. "Platelets are usually increased (> 500,000) in rheumatoid arthritis, most cancers, trauma (hemorrhage), polycythemia, and some anemias (iron deficiency). They are decreased in bleeding tendencies (usually < 20,000 per mm3 before bleeding occurs), purpura (a condition in which even the slightest bruise causes a black-and-blue mark from bleeding under the skin), some anemias, certain leukemias, and infectious mononucleosis."-

Normal Values - 150,000 - 500,000 per mm3 (lower for children).-

When Performed - "When there are obvious bleeding tendencies; before surgical procedures; with fractures; to check liver function; when polycythemia or certain kinds of anemia are suspected; when leukemia is being treated."-

Symptoms/Functions - Platelets are less than half the size of red blood cells and are essential to the blood clotting process. "They are manufactured in bone marrow at the rate of about 100,000 per day. When bleeding occurs platelets group together, swell up, stick to the injured area, and attempt to act as plugs to stop the bleeding. The normal life span for platelets is about 8 days."-

 

Prothrombin Time - Measures the amount of time it takes for a "fibrin strand (first sign of clotting) to be seen." A longer amount of time indicates a lower percentage of prothrombin activity (slower clotting). The time is prolonged with the use of anticoagulant drugs, liver disease, and low levels of vitamin K. -

Normal Values - 12-14 seconds-

When Performed - "Primarily as an indication of certain anticoagulant drugs; as an indication of how the liver is functioning; as a measure of a patients dietary intake of viamin K."-

Symptoms/Functions - "Prothrombin is one of the 12 known factors necessary to stop bleeding…It is manufactured in the liver from vitamin K, which is obtained in the diet primarily from green leafy vegetables, fish, and liver."-

 

Red Blood Cell Count - "Red blood cells are counted and stained to reveal the size, shape, and hemoglobin content. Sickle cells are seen directly this way , as are certain anemias. Higher than normal values are usually found with polycythemia, dehydration, certain kidney diseases, and lung conditions where there is trouble breathing and the body needs more oxygen. Lower than normal values are usually found with anemias, severe infections, certain cancers, Malaria, lead poisoning, and after prolonged bleeding."-

Normal Values - 4-6 million per mm3 -

When Performed - "When there is suspicion of one of the anemias or polycythemia (a disease where the bone marrow makes too many red blood cells); in certain parasitic diseases; to verify certain poisonings; to help determine blood loss after hemorrhage."-

Symptoms/Functions - "The red blood cells (erythrocytes) contain hemoglobin, which is the essential carrier of oxygen in the blood. Besides carrying oxygen to all parts of the body, red blood cells pick up certain waste products (such as carbon dioxide) that are given off later by the lungs."-

 

White Blood Cell Count - Total count of the 5 kinds of white cells. "The amount of certain kinds of white blood cells usually increases with infections, blood disorders, emotional stress, hemorrhage, rheumatic fever, and burns. The white blood cell count decreases following ingestion of certain drugs or chemicals, after x-ray treatments, with malaria, typhoid, brucellosis, certain forms of leukemia, and virus and rickettsial infections." Normal Values - 5,000-10,000 per mm3 (children may have higher values).-

When Performed - " When infection is suspected; in toxic reactions to certain drugs (sulfa drugs and other antibiotics; analgesics); in toxic reactions to chemicals or poisons (arsenic); in blood disorders, especially leukemias."-

Symptoms/Functions - "The five different types of white blood cells are formed and stored in the bone marrow, thymus, lymph glands, and spleen. They are particularly important in fighting infections. -

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