A urine analysis may show high blood sugar. However, a urine test alone does not diagnose diabetes.

Your health care provider may suspect that you have diabetes if your blood sugar level is higher than 200 mg/dL. To confirm the diagnosis, one or more of the following tests must be done.

Blood tests:

• Fasting blood glucose level -- diabetes is diagnosed if it is higher than 126 mg/dL twice. Levels between 100 and 126 mg/dL are called impaired fasting glucose or pre-diabetes. These levels are risk factors for type 2 diabetes.
• Hemoglobin A1c test --
  • Normal: Less than 5.7%
  • Pre-diabetes: 5.7% - 6.4%
  • Diabetes: 6.5% or higher
• Oral glucose tolerance test -- diabetes is diagnosed if glucose level is higher than 200 mg/dL after 2 hours of drinking a glucose drink. (This test is used more often for type 2 diabetes.)

Screening for type 2 diabetes in people who have no symptoms is recommended for:

• Overweight children who have other risk factors for diabetes, starting at age 10 and repeated every 2 years
• Overweight adults (BMI greater than 25) who have other risk factors
• Adults over age 45, repeated every 3 years

For more information, see American Diabetes Association -- www.diabetes.org

Keeping an ideal body weight and an active lifestyle may prevent type 2 diabetes.

There is no way yet to prevent type 1 diabetes.

Alemzadeh R, Ali O. Diabetes Mellitus. In: Kliegman RM, ed. Kliegman: Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders;2011:chap 583.

American Diabetes Association. Standards of medical care in diabetes -- 2012. Diabetes Care. 2012; 35 Suppl 1:S11-S63.

Pignone M, Alberts MJ, Colwell JA, Cushman M, Inzucchi SE, Mukherjee D, et al. Aspirin for primary prevention of cardiovascular events in people with diabetes: a position statement of the American Diabetes Association, a scientific statement of the American Heart Association, and an expert consensus document of the American College of Cardiology Foundation. Circulation. 2010;121:2694-2701.

Eisenbarth GS, Polonsky KS, Buse JB. Type 1 Diabetes Mellitus. In: Kronenberg HM, Melmed S, Polonsky KS, Larsen PR. Kronenberg: Williams Textbook of Endocrinology. 11th ed. Philadelphia, Pa: Saunders Elsevier; 2008:chap 31.