What are other Names for this Test? (Equivalent Terms)

• Glucose Capillary Blood Test
• Glucose Finger-Stick Blood Test

What is Glucose Self-Monitoring Blood Test? (Background Information)

• Glucose is a simple sugar that serves as the body’s main energy source. Some organs, such as the brain, use glucose exclusively for energy
• Glucose is obtained through the diet directly and indirectly. Foods may contain glucose; alternatively, more complex sugars, such as maltose, lactose, and starch, are broken down and their components converted into glucose
• After a meal, blood glucose levels may rise markedly. Conversely, they may fall after a strenuous workout has forced muscles to use up the body’s glucose stores
• Blood glucose levels must be maintained within a relatively narrow range. Excess glucose in blood may damage tissues, while deficiencies may cause fatigue, lightheadedness, and brain malfunction
• The body compensates for the various factors that impact blood glucose levels through the use of hormones. Two such sugar-regulating hormones are insulin and glucagon. They play opposing roles:
  • Insulin is made by beta cells of the pancreas. It is released in blood after a rise in blood glucose (such as after a heavy meal), to help lower it to normal levels by stimulating cells to take in glucose and other nutrients
  • Glucagon is made by the alpha cells of the pancreas and has the opposite effect. It is released when glucose levels fall below normal (such as after a workout) and causes cells to produce glucose and release it from their stores
• Problems with either of these mechanisms may cause abnormalities in blood glucose levels that can even be life-threatening
• The most common cause of elevated glucose is diabetes mellitus, or simply “diabetes”. There are 3 types of diabetes mellitus, all of which stem from problems with insulin function:
  • Type 1, or insulin-dependent, diabetes results from the autoimmune destruction of beta cells of the pancreas
  • Type 2, or insulin-independent, diabetes results from the desensitization of cells to the effects of insulin
  • Gestational diabetes may occur during pregnancy and result in excessively large babies that exhibit low glucose levels
• The Glucose Self-Monitoring Blood Test helps determine the levels of glucose in blood through the use of portable, user-friendly devices. It is used to diagnose diabetes, cancers, and other metabolic disorders
• Current tests offer reliable glucose readings in less than 2 minutes. They are also less invasive and easier to use than previous versions of the test

What are the Clinical Indications for performing the Glucose Self-Monitoring Blood Test?

Following are the clinical indications for performing the Glucose Self-Monitoring Blood Test:

• Monitoring glucose levels of individuals with diabetes
• Frequent urination
• Increased thirst
• Fatigue
• Blurry vision
• Rapid weight loss
• Tingling and numbing in the extremities
• Giving birth to a baby over 9 pounds
• Obesity
• History of cardiovascular disease

How is the Specimen Collected for Glucose Self-Monitoring Blood Test?

Following is the specimen collection process for Glucose Self-Monitoring Blood Test:

Sample required: Blood 

Process of obtaining a blood sample in adults using the fingerstick method:

• Check the procedure for the specific device to be used
• Cleanse the site (side of the forefinger) with alcohol or other topical germicides
• Wipe-off the first drop of blood
• Avoiding “milking” the finger, wait for a large drop of blood to form
• Cover the pad of the reagent strip with the drop of blood
• Place the strip into the meter for reading. Follow the instructions on the meter
• Apply pressure to stop the bleeding

Preparation required: No special preparation is needed prior to the test.

What is the Significance of the Glucose Self-Monitoring Blood Test Result?

The significance of the Glucose Self-Monitoring Blood Test result is explained.

• A high value (greater than 110 mg/dL for an adult, 85 mg/dL for a child) for the test may indicate:
  • Diabetes mellitus
  • Acromegaly
  • Cushing’s syndrome
  • Glucagonoma
  • Severe liver disease
  • Pheochromocytoma
  • Pancreatitis
  • Hyperalimentation
• A low value (less than 60 mg/dL for an adult, 50 mg/dL for a child) for the test may indicate:
  • Addison’s disease
  • Galactosemia
  • Hereditary fructose intolerance
  • Hypopituitarism
  • Insulinoma
  • Malabsorption syndromes
  • von Gierke disease
  • Insulin overdose

The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.

Additional and Relevant Useful Information:

• The Glucose Self-Monitoring Blood Test may not provide reliable results when glucose levels are very low (less than 50 or 60 mg/dL) or very high (greater than 450 or 500 mg/dL)
• Diabetes insipidus is a rare disorder whereby the kidneys cannot conserve water

Certain medications that you may be currently taking may influence the outcome of the test. Hence, it is important to inform your healthcare provider of the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid unnecessary chances of a misdiagnosis.

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/common-procedures/procedures-laboratory/glucose-blood-test/

Please visit our Laboratory Procedures Center for more physician-approved health information:

http://www.dovemed.com/common-procedures/procedures-laboratory/