Lab Test Explanations

CBC (Complete Blood Count)

Complete Blood Count is an essential test for almost all patients. It detects anemia, infections, leukemia, mononucleosis, and many other diseases. A complete blood count includes the following tests:

  • White blood count: Determination of the number of white blood cells (leukocytes) in a measured volume (usually a cubic millimeter). There are several different types of white blood cells; they all form the first line of defense against disease.
    – High: Infection, leukemia, cancer
    – Low: Low immunity, leukemia, cancer.
  • Red blood count: Determination of the number of red blood cells (erythrocytes) in a measured volume.
    – High: Lung disease, blood cancer kidney disease.
  • Hemoglobin: The red coloring material/the oxygen carrying pigment of the red blood cell. Formed in the bone marrow, it carries oxygen from the lungs to the tissue and carbon dioxide from the tissue to the lungs.
    – High: Same as for red blood count, shortness of breath.
  • Hematocrit: The percentage of red blood cells to the original blood volume. The count depends mostly on the number of red blood cells, and to some extent the average size of the red blood cell. Usually the count is about 3 times the hemoglobin value (assuming no marked hypochromia).
    – High: Same as red blood count.
    – Low: Same as red blood count.
  • MCV: Mean corpuscular volume is the average measure (volume) of the size of red blood cells.
    – High: Lack of B12, low folic acid, pernicious anemia.
    – Low: Low iron, sickle cell disease.
  • MCH: Mean corpuscular hemoglobin is an estimate of the amount of hemoglobin in the average red blood cell.
  • MCHC: Mean corpuscular hemoglobin concentration is an estimate of the average hemoglobin concentration of the average RBC. This depends on red cell size as well as on the actual amount of hemoglobin contained in the cell.
  • Platelet count: Disk shaped cell primarily influencial in blood clotting.
    – High: Blood disease.
    – Low: Bruising, bone marrow disease.
  • Monocytes: A mononuclear white blood cell (leukocyte) formed in the bone marrow and transported to tissues such as the lungs and liver. Their function is to aid in antibody production in the event if infection or inflammation.
    – High: Mononucleosis, leukemia, fatigue, fever, sore throat, swollen lymph nodes.
  • Granulocytes: Any cell containing granules especially a white blood cell (leukocyte).
    – High: Bacterial infection, leukemia.
    – Low: Low immunity.


This is an analysis of at least 29 different chemical elements in the blood. It includes kidney and liver function as well as some minerals, blood sugar, enzyme levels, etc. Included in it are the following tests:

  • Calcium: An essential dietary element. Constant blood calcium is necessary for the maintenance of a normal heartbeat, and normal functioning of nerves and muscles. The most abundant mineral in the body, it combines with phosphorus to form teeth and bones. It is also important in blood clotting (coagulation) and many enzyme functions.
    – High: Hyperparathyroidism, cancer, bone disease.
  • Ionized Calcium: Same as above.
    – High: Same as above.
  • Phosphorous: A mineral, a major component of bone, and abundant in all tissue. It’s essential in almost every chemical reaction in the body. Phosphorous is absorbed from the intestine into the blood and stored in bones and teeth. Absorption is dependent on vitamin D and calcium, but inhibited by excessive iron, aluminum, and magnesium.
    – High: May be indicative of kidney failure, and/or hypoparathyroid.
    – Low: Can cause arthritis, pyorrhea, rickets, tooth decay, weight loss or gain, irregular breathing, mental and physical fatigue, and nervous disorders.
  • Alkaline Phosphatase: A phosphate enzyme active in an alkaline medium such as blood serum or plasma, bone, kidneys, mammary glands, spleen, lung, adrenal cortex, etc.
    – High: Elevations occur in liver and bone disorders, the third trimester of pregnancy, osteoporosis, fractured bones, multiple myeloma, etc. Extremely high levels are most often seen in bile duct obstruction, cholestasis, and Paget’s Disease of the bone.
  • Bilirubin, Total: Bilirubin is a bile pigment, a breakdown product of heme. It normally circulates in the plasma as a complex with albumin and is taken up by the liver. Total is the sum of “direct” and “indirect.”
  • Bilirubin, Direct: Accumulates in the blood and tissues and is excreted in the urine.
  • Bilirubin, Indirect: Not excreted in the urine.                                                                                                                                                  – High: High concentrates may result in jaundice, or indicate severe liver disease.
  • AST (SGOT): Serum glutamic oxaliacetic acid is primarily present in the heart, liver, skeletal muscles, and kidneys.
    – High: Can indicate disease in any of the above areas. Ex: hepatitis, infectious mononucleosis, cirrhosis, muscular dystrophy, etc. When heart attack occurs, highest levels of SGOT are roughly proportional to the degree of cardiac damage.
    – Low: Can indicate pregnancy.
  • ALT (SGPT): Serum glutamic pyruvic transsaminase is an enzyme normally present in the liver and other body tissues. It is released into the blood as a result of tissue injury or whenever a disease affects the liver, kidney, heart, or skeletal muscles.
    – High – Very high: hepatitis, infectious mononucliosis.
    – Moderately high: cirrhosis and jaundice.
    – Occasional: muscular dystrophy, myocardial infarction, dermatomyositis.
  • LDH: Lactic dehydrogenase is widespread in tissues, particularly the kidneys, skeletal muscles, liver, and myocardium. It is an enzyme that catalyzes the interconversion of lactate and piruvate, and appears in elevated concentrations when these tissues are injured by disease and/or trauma.
    – High: Tissue injury, blood clots.
  • Gamma GT: Confirms the liver origin of elevated alkaline phosphatase. Isolated or disproportionate elevations are found in alcohol abuse.
    – High: Occurs in most types of liver disease.
  • Total Protein: Albumins and globulins are the most abundant proteins in the blood. Improper digestion and/or utilization affect total protein concentration. High or low serum protein levels require further diagnostic testing to determine which protein is involved.
  • Albumin: Protein found in animal and vegetable tissue. Transports fatty acids, bilirubin, and poorly soluble hormones. Aids in the maintenance of osmotic pressure and binding of toxic metals. Distributed throughout the body, including bone and skin. In healthy people, dehydration from exercise increases albumin levels, bed rest decreases concentrations.
    – High: Excess protein intake, dehydration.
    – Low: May indicate liver disease which in turn affects the supply of amino acids to the liver. Increases in utilization of albumin by liver, spleen, kidney, and muscles may result in hypoalbuminemia (low albumin), or a large variety of diseases or injuries.
  • Globulin: A type of protein not soluble in water.
    – High: Pregnancy, hypothyroidism, biliary cirrhosis, obstructive jaundice, hepatitis, nephrosis.
    – Low: Malnutrition.

A/G Ratio (Albumin to Globulin ratio)

  • CPK, Total: Creatinine phosphokinase is an enzyme of the skeletal muscle, myocardium, and brain tissue that catalyzes transfer of a phosphate group thus producing creatinine and ATP (adenosine triphosphate), both integral in energy production.
  • BUN: Blood urea nitrogen is measurerd to determine kidney function; the count usually parallels creatinine.
    -High: Usually indicates a kidney disorder or too much protein in the diet. -Low: Excessive fluid intake
  • Creatinine: Final waste product of protein metabolism and is found in the muscles and blood and is excreted in the urine. Measurement of serum creatinine determines renal function.
    – High: Suggests chronic kidney disease.
    – Low: Excessive fluid intake.
  • BUN/Creatinine ratio:
    – High: Prerenal or postrenal azotemia.
    – Low: Primary renal disease.
  • Glucose: Blood sugar is the end product of carbohydrate metabolism, the body’s chief source of energy. Utilization of glucose is controlled by insulin.
    – High: Generally indicative of diabetes mellitus                                                                                                                                                   – Low: When combined with high insulin indicates insulinoma, hypoglycemia, etc.
  • Uric acid: The major end product of animal protein metabolism, elimated by the kidneys, and a common constituent of kidney stones.
    – High: Excessive protein in the diet, stress related, gout or inflammatory arthritis due to uric acid deposits in the tissues, diabetes, and/or the use of diuretics. Accumulations in the kidneys may lead to stones and kidney failure.
    – Low: May indicate liver disease or over-consumption of fluids.
  • Sodium: Essential mineral found predominantly in extracellular fluids, vascular fluids, arteries, veins and capillaries, intestinal fluids surrounding cells, and within the bones. Functions with potassium to equalize the acid-alkali factor in the blood, helps regulate water balance in the body, and is involved in muscle relaxation/contraction and nerve stimulation.
    – High: Potassium loss, edema, dizziness, high blood pressure.
    – Low: Treatment with diuretics, overhydration, glandular problems.
  • Potassium: Essential mineral found mainly in the intracellular fluid. 5% of the total mineral content of the body. Necessary for normal growth and stimulation of nerve impulses for muscle contractions. Aids in keeping the skin healthy. Assists in the conversion of glucose to glycogen for storage in the liver. Functions in cell metabolism, enzyme reactions, synthesis of muscle protein from amino acids, maintaining regular heartbeat, and getting oxygen to the brain by uniting with phosphorus.
    – High: Kidney failure, severe lack of fluid, hypoglycemia. *Acidosis tissue has a potassium deficit when plasma levels are registering normal or high.
    – Low: Excessive use of salt, inadequate fruits and vegetables, stress, severe malnutrition, nervous disorders, insomnia, constipation, slow and irregular heartbeat, muscle damage, diabetes, excessive cortisone and/or aldosterone, weakness, sagging muscles, acne, dry skin.
  • Chloride: Essential mineral mainly in combination with sodium and potassium. Helps regulate acid/alkali balance, stimulate production of hydrochloric acid for protein and fibrous food digestion. Stimulates the liver to function as a filter for waste products. Aids in keeping joints and tendons in youthful condition and helps distribute hormones.
    – High: Too much salt in diet, kidney failure.
    – Low: Hair and tooth loss, poor muscular contraction, impaired digestion, diuretic use.
  • Carbon Dioxide: Gas formed in the tissues and eliminated by the lungs. Assists in maintaining neutrality of body tissues and fluids.
    – High: Lung disease, acidosis.
    – Low: Hyperventilation, kidney disease.

Anion Gap: Indicates Metabolic Acid/Base Imbalance

  • Cholesterol: A lipid or fat-related substance necessary for good health. It is a normal component of most body tissue especially the brain, nervous system, liver, and blood. Necessary to form the sex and adrenal hormones, vitamin D, and bile. It also plays a role in skin lubrication. Lecithin decreases cholesterol in some people.
    – High: Elevated lipids may be present in diabetes, hypothyroidism, nephrotic syndrome, pancreatitis, or alcoholism. Leads to hardening of the arteries, heart attacks, strokes.
    – Low: May indicate severe liver damage, hypothyroidism, malnutrition, or other severe infections.
  • Triglycerides: Large fat molecules made from carbohydrates which break down during enzymatic hydrolysis into free fatty acids. Free fatty acids pass from the intestine into the blood. High blood levels produce fat deposits along artery walls. Free fatty acids are increased with consumption of sugar, white flour, refined/processed carbohydrates, alcohol, etc.
    – High: Diabetes, hypertension, heart disease, aches, and pains.
  • LDL: Low density lipoproteins: The worst type of cholesterol.
    – High: Heart problems, hardening of the arteries.
  • Iron: An essential mineral present in every cell. All iron is associated with protein. The major function of iron is to combine with copper and protein in the production of hemoglobin. Iron is also necessaary for the formation of enzymes that facilitate protein metabolism. Absorbtion is from the upper small intestine and is facilitated by ascorbic acid. Iron is stored in the liver, spleen, bone marrow, and blood.
    – High: May indicate cirrhosis of the liver, diabetes, pancreas insufficiency, hemolytic or aplastic anemia, Gilbert’s disease. Too much iron can result in siderosis, damage to the heart, liver, and/or pancreas.
    – Low: May indicate hypochromic anemia, GI bleeding, malnutrition, pregnancy.


  • Color: Color should be pale yellow. Other colors may indicate the following:                                                                                               – Brown: dehydration. Red: blood. Dark orange: bile.
  • Appearance: Usually reported only if abnormal.
  • Specific gravity: Indicative of renal function. May indicate diabetes insipidus, or severe hyperthyroidism, or sickle cell anemia. It also has an effect on the other aspects of a urine test. If lower than 1010, too much fluid. If higher than 1020, too little fluid.
  • Leukocytes: White blood cells sometimes found in urine. More than 3 indicate infection.
  • Nitrite: A salt of nitrous acid sometimes found in urine. Positive in infection.
  • Ph: Normal urine is acidic. It may be alkaline in alkalosis or in some specific cases of kidney disease. If lower than 6.5, your body is too acidic. If higher than 7.0, too alkaline.
  • Protein: Indicates the amount and the size of protein molecules. Since there are many types of protein, different types can indicate different problems. Positive in kidney disease, too much protein in diet, or diabetes.
  • Ketone: An organic compound found in diabetes, etc.
  • Urobilinogen: Appears classically as a secondary product from increased red blood cell breakdown. May also be present in hepatitis.
  • Bilirubin: Conjugated bilirubin is excreted in the urine and elevated levels may indicate cholestasis.
  • Red blood cells: Gross urinary bleeding can indicate stones, tumors, tuberculosis, and acute glomerulonephritis. Occasional bleeding can indicate bleeding and clotting disorders, blood dyscrasias, renal infarction, malignant hypertension, collagen diseases, various bladder and prostatic conditions.
  • White blood cells: Indicates an infection in the urinary tract. Epithelial cells: May indicate infection of the kidney or urinary tract.
  • Bacteria: May indicate an infection.
  • Casts: Fatty casts, RBC, and WBC casts are always significant.

Thyroid Profile


  • TSH (thyroid stimulating hormone): The higher this number the slower the thyroid function.
  • T3 uptake Thyroxine: (T4) Free thyroxine index.
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