Health Literacy and Endocrine System Tests
Knowledge and understanding of the medical terminology pertaining to common laboratory tests performed to evaluate common endocrine disorders and endocrine system function is an important aspect of health literacy. It can also aid in understanding information regarding your health and health care. Listed below are medical terms and definitions pertaining to some of the most common tests. To augment your learning experience you can hear the medical pronunciation of the terms in bold font in the chronological order in which they appear. Just click the play button below.
Chloride – Is the negatively charged ion of the sodium chloride (salt) molecule. It is the most abundant negatively charged electrolyte in blood and other body fluids outside of cells. Serum sodium refers to the amount of sodium in the blood stream. Its concentration is what is measured. Its symbol is Cl+.
Glycemic control – Is a term meaning degree of blood glucose control. Short-term glycemic control refers to the degree of blood sugar control from day to day. Long-term glycemic control refers to the degree of control over a period of 2-3 months as reflected by hemoglobin A1c measurements.
Hemoglobin A-1 C – Hemoglobin is the oxygen carrying protein in red blood cells. Hemoglobin A-1 C is the protein with sugar attached to it. The percentage of hemoglobin in blood which is hemoglobin A-1 C is an indicator of the average amount of glucose in the blood during the preceding 2-3 months. Thus, measurement of hemoglobin A-1 C is a test for determining long-term glycemic control. Also, hemoglobin A1c recently received FDA approval for diagnosing type 2 diabetes mellitus and pre-diabetes.
Hypernatremia – It is an abnormally high concentration of sodium in the bloodstream.
Hyponatremia – It is an abnormally low concentration of sodium in the bloodstream. Sodium when measured by laboratory normally ranges between 135 and 145 mEq per liter. Seizures can occur when the blood sodium concentration drops below 125 mEq per liter.
Oral glucose tolerance test (OGTT) – Is one of the tests used to diagnose diabetes mellitus. It involves drawing and testing blood for glucose at different intervals of time. Blood is first drawn and tested in the fasting state. Repeat blood drawing and glucose testing is then performed every 30 to 60 minutes after the person being tested has drunk 75 grams of glucose dissolved in liquid. The maximum duration of the test is up to three hours. Blood sugar readings higher than normal establish or confirm a diagnosis of diabetes mellitus, gestational diabetes or prediabetes barring any other cause of an abnormally high reading such as extreme acute illness or corticosteroid use. Normal readings during the study are as follows:
- 2 hour glucose greater than 200 mg/dl = Provisional Diagnosis of Diabetes (Must be confirmed on a subsequent date with a repeat OGTT or another approved method of testing)
New ADA guidelines for diagnosing gestational diabetes with a 75-gram OGGT are as follows:
- Fasting glucose – greater than 92 mg/dl
- 2-hour: greater than or equal to 153 mg/dl
Potassium – It is the most abundant positively charged electrolyte of the fluid inside of cells. Serum potassium refers to the amount of potassium in the blood stream. Its concentration is what is measured. Its symbol is K+.
Random blood glucose – Is the blood glucose reading obtained when the measurement is performed on blood at any time of the day without regard to the last meal. A reading of 200 or greater with classic symptoms of diabetes such as increased thirst and urination confirms the diagnosis.
Sodium – Is the positively charged ion of the sodium chloride (salt) molecule. It is the most abundant positively charged electrolyte in blood and other body fluids outside of cells. Serum sodium refers to the amount of sodium in the blood stream. Its concentration is what is measured. Its symbol is Na+.