Diagnosis of Type 1 Diabetes
The doctor will ask about your symptoms and medical and family history. A physical exam will be done. The doctor will also do a few tests. There are four main tests used to diagnose diabetes. The American Diabetes Association (ADA) list the following test as options for diagnosis:
Symptoms and Results of Random Plasma Glucose TestSymptoms typical of diabetes include excessive thirst and hunger, frequent urination, and weight loss. Your doctor will make the diagnosis based on your symptoms and the results of the random plasma glucose test. This test is taken any time of day, without regard to when you have last eaten. A sample of your blood will be taken. The blood glucose level will be measured. A measure of 200 (mg/dl) [11.1 mmol/L] or higher indicates the presence of diabetes.
Two-hour Glucose Tolerance TestThis starts with a three-day intake of a diet consisting of at least 150 grams of carbohydrates. You will then be asked to fast overnight (between 8-16 hours). The test is generally done in the morning, in your doctor's office.A sample of your blood will be obtained to measure blood sugar. Then, you will consume a drink that contains 75 grams of glucose dissolved in water. Two hours later, another blood sample will be obtained to measure blood sugar. If you have diabetes, your blood sugar level will rise higher than normal and remain high for a much longer time than is normal. A measure of 200 mg/dl (7 mmol/L) or above at two hours is considered a positive test.
Hemoglobin A1c (HbA1c)The HbA1c test is a good indicator of your average blood sugar levels over the previous 2-4 months. This test usually does not require any dietary restrictions. A sample of your blood will be taken. If your HBA1c level is 6.5% or higher, this indicates a diagnosis of diabetes.
Fasting Plasma Glucose TestYou will need to eat nothing for at least eight hours before the test. A sample of your blood will be taken. The blood glucose level will be measured. A measure of 126 milligrams per deciliter (mg/dl) (7 millimole per liter of blood [mmol/L]) or higher on two separate occasions indicates a diagnosis of diabetes.
Other TestsAfter the diagnosis of diabetes is confirmed, your doctor will most likely order the following tests:
- Urine microalbumin—to see if there is any damage to your kidneys by measuring protein in your urine
- Thyroid function tests
- Blood lipids (cholesterol) levels (total low-density lipoprotein [LDL] and high-density lipoprotein [HDL] cholesterol, triglycerides)
- Kidney function tests including serum creatinine, blood urea nitrogen (BUN), and potassium
- Glutamic acid decarboxylase (GAD) antibodies
- Plasma insulin levels
- Islet cell antibodies
- Plasma C-peptide
- Insulin antibodies
More from Beliefnet
Many medical groups felt that early exposure to certain foods like peanuts increased a child's risk of developing food allergies. However, newer research including this trial suggest that early exposure may actually decrease the risk of developing food allergies.
Breastfeeding May Decrease the Risk of Childhood Obesity
Tonsillectomy May Reduce Number of Sore Throat Days in Children
Research Review Finds Little Support for Nearly Half of Medical Talk Show Recommendations