What routine urine test is recommended for a patient with suspected or established diabetes?

Routine Urine Testing for Diabetes

Urine glucose testing is not recommended for routine care of patients with diabetes, and has been supplanted by self-monitoring of blood glucose (SMBG) and hemoglobin A1c testing. 1

Urine Glucose Testing: Not Recommended

• Urine glucose testing should not be performed routinely in diabetes management. 1
• Despite relatively low cost and ease of specimen collection, the well-described limitations of urine glucose testing make SMBG the preferred method for monitoring glycemic control. 1
• Laboratory blood glucose testing should only be used to supplement information from SMBG and glycated protein testing, not as a routine assessment tool. 1

Urine Albumin Testing: The Essential Routine Test

The routine urine test you should perform for diabetes is urine albumin measurement using a spot urine albumin-to-creatinine ratio (uACR). 1

When to Test

• Annual testing for albuminuria should begin:
  • In type 1 diabetes: 5 years after diagnosis in pubertal or post-pubertal individuals 1
  • In type 2 diabetes: at the time of diagnosis, regardless of treatment 1

How to Perform the Test

• Use a first morning void urine sample for measurement of albumin-to-creatinine ratio. 1
• If first morning void is difficult to obtain, collect all samples at the same time of day with the patient well-hydrated, having not eaten within 2 hours or exercised. 1
• The test should be reported as milligrams of albumin per gram of creatinine, with a reference range of ≤30 mg/g creatinine. 1

Interpretation

• Normal: ≤30 mg albumin/g creatinine 1
• Microalbuminuria: >30 to 300 mg albumin/g creatinine 1
• Macroalbuminuria: >300 mg albumin/g creatinine 1

Follow-up Testing

• If estimated glomerular filtration rate is <60 mL/min/1.73 m² and/or albuminuria is >30 mg/g creatinine, repeat the uACR every 6 months to assess change. 1
• To confirm persistent albuminuria, repeat testing should show values >30 mg/g creatinine in 2 of 3 tested samples. 1

Urine Ketone Testing: Situational Use Only

Urine ketone testing is not a routine test but should be available for specific clinical situations. 1

When to Test for Ketones

• Individuals prone to ketosis (type 1 diabetes, history of diabetic ketoacidosis, or treated with SGLT2 inhibitors) should measure ketones if they have unexplained hyperglycemia or symptoms of ketosis such as abdominal pain or nausea. 1
• Testing should be performed during acute illness, stress, consistently elevated blood glucose (>300 mg/dL), during pregnancy, or with symptoms of ketoacidosis. 1

Important Limitations

• Blood beta-hydroxybutyrate measurement is preferred over urine ketone testing for diagnosing and monitoring diabetic ketoacidosis. 1, 2
• Standard urine dipsticks using the nitroprusside method only measure acetoacetate and acetone, not beta-hydroxybutyrate, which is the predominant ketone body in DKA. 2
• Urine ketones have high sensitivity but poor specificity and can be positive in up to 30% of normal fasting individuals and pregnant women. 2

Common Pitfalls to Avoid

• Do not use urine glucose testing to guide diabetes management decisions—it has been replaced by more accurate methods. 1
• Do not use timed urine collections for albumin measurement in clinical practice—spot urine albumin-to-creatinine ratio is the standard. 1
• Do not rely on urine ketone testing alone for DKA diagnosis or monitoring—blood beta-hydroxybutyrate is superior. 2
• Avoid testing for urine albumin after vigorous exercise within 24 hours, as this can cause false-positive results. 1