Laboratory Results

We have always contacted our patients with laboratory and diagnostic test results that demand attention. With our patient portal we can now easily advise you of results through the Internet whether or not there are critical results. Sometimes the detail of the results can be confusing and raise questions. This simple guide is intended to focus your attention to the important lab test components that you can begin to understand without a medical education.

 It is important to realize that laboratory results may be outside of the so-called "normal range" for many reasons. These variations may be due to such things as race, diet preference, age, sex, menstrual cycle, degree of physical activity, problems with collection and/or handling of the specimen, alcohol, prescription and even non-prescription drugs. It is not possible to diagnose any disease or problem with a blood test alone. They can help you to learn about your body and detect potential problems in early stages when treatment or changes in personal habits can be most effective.

All labs set the normal result range for a particular test so that 95% of our healthy patients fall within the normal range. That means that 5% of healthy patients fall outside of the normal range, even when there is nothing wrong with them. Thus an abnormal test does not necessarily mean that there is something wrong. Part of what you see your doctor for is to interpret whether or not these changes are meaningful.

Complete Blood Count (CBC)

White Blood Count (WBC):  The white cells operate the immune system and fight infection. High WBC can be a sign of infection.  Low white counts can be a sign of bone marrow diseases and the undesired effect of some medications used to treat arthritis.

Hemoglobin (Hgb) and Hematocrit (Hct) : The hemoglobin is the amount of oxygen carrying protein contained within the red blood cells. The hematocrit is the percentage of the blood volume occupied by red blood cells. A low Hgb or Hct suggest an anemia. Anemia can be due to nutritional deficiencies, blood loss, destruction of blood cells internally, or failure to produce blood in the bone marrow.

Platelet Count (PLT) : These cells plug up tears in your blood vessels and prevent bleeding. High values can occur with bleeding, cigarette smoking or excess production by the bone marrow. Low values can occur from premature destruction states caused by medications , infections, or bone marrow failure from diseases. Low platelets also can occur from clumping of the platelets in the collection tube.

Chemistry Panel

Electrolytes: These are your potassium, sodium, chloride, magnesium and CO2 levels. They are important for the proper functioning of the brain, nerves, skeletal and heart muscle.

Waste Products: Blood Urea Nitrogen (BUN) is produced in the liver and excreted by the kidneys. High values may mean that the kidneys are not working as well as they should. BUN is increased by high protein diets and/or strenuous exercise. Creatinine is from muscle breakdown. It will increase when there is kidney failure or muscle damage. Uric Acid is normally excreted in urine. High values occur with gout and diuretics.      

Enzymes: AST, ALT, SGOT, SGPT, LDH, CPK and Alkaline Phosphatase are proteins called enzymes which help all the chemical activities within cells occur. Injury or natural death of cells release these enzymes into the blood. Higher concentrations are found in muscle, liver and heart. Damage from alcohol and a number of diseases result in high values. Alkaline phosphatase is found primarily in bones and the liver. Expected values are higher for growing children or when damage to bones or liver occurs. Low values are probably not significant. LDH is the enzyme present in all the cells in the body. Anything which damages cells, including blood drawing itself, will raise amounts in the blood. If blood is not processed promptly and properly, high levels may occur. CPK is useful for diagnosing diseases of the heart and skeletal muscle. This enzyme is the first to be elevated after a heart attack. If CPK is high in the absence of heart muscle injury, this is an indication of skeletal muscle disease.

Bilirubin:  A pigment removed from the blood by the liver. It indicates another aspect of liver function. Low values are of no concern.

Proteins: Albumin and Globulin measure the amount and type of protein in your blood. They are a general index of overall health and nutrition. Globulin is the "antibody" protein important for fighting disease.

Minerals: Calcium is controlled in the blood by the parathyroid glands and the kidneys. Calcium is found mostly in bone and is important for proper blood clotting, nerve, and cell activity. Elevated calcium can be due to medications such as some diuretics, the kidneys, excess parathyroid gland activity or vitamin D. Low calcium can be due to disorders such as insufficient parathyroid hormone; or drugs like Fosamax or furosemide type diuretics. Calcium is carried by albumin in the blood, so a low albumin level will cause the measured total calcium level to seem low. Phosphorus is also largely stored in the bone. It is regulated by the kidneys, and high levels may be due to kidney disease. 

Sedimentation Rate 

Erythrocyte Sedimentation Rate (ESR or Sed Rate) is a common measure of inflamation. Normal values are below 30. Mild infections can increase it slightly. C Reactive Protein (CRP) is an alternate test that also measures inflamation.


Specific Gravity (SG) : This measures how dilute your urine is, suggesting whether you are dehydrated. Water would have a SG of 1.000. Most urine is around 1.010, but it can vary depending on when you drank fluids last.

Glucose: Normally there is no glucose in urine. A positive value should raise the possibility of diabetes or glucose intolerance.

Protein: Normally there is little or no protein detectable. Protein can indicate kidney damage, blood in the urine, or an infection. 

Blood: Normally there is no blood in the urine. Blood can indicate an infection, kidney stones, trauma, or bleeding from a bladder or kidney tumor. 

Leukocyte esterase: Normally negative. Leukocytes are the white blood cells. White blood cells in the urine suggests a urinary tract infection.

Sediment: The urine is inspected with a microscope. Items such as mucous and squamous cells are commonly seen. Bacteria and squamous cells may indicate contamination when the specimen was not collected carefully.

Antinuclear Antibodies

 The immune system makes many proteins called antibodies to protect us. Unfortunately sometimes a mistake can occur and antibodies can target normal proteins. Some of the earliest identified were found to target the nucleus of our cells. These abnormal antibodies are called Antinuclear Antibodies (ANA). Fortunately this does not indicate the diagnosis of an autoimmune disease or the need for treatment. About 10 - 15% of healthy people have ANA. Other causes which we want to identify are; autoimmune diseases such as lupus, older age, certain medications and some cancers. A final determination of the significance of the ANA occurs after evaluation for health problems with medical history, physical examination and laboratory testing. Sometimes we will test for additional auto-antibodies (antibodies against normal proteins) to help understand whether there is a specific diagnosis.