Protein normally is not found in urine. When the kidneys are damaged by diabetes, small amounts of protein begin to leak into the urine. If blood sugar levels stay high and early kidney damage is left untreated, larger amounts of protein may be lost, possibly leading to kidney failure.
Urine tests for protein levels in people with diabetes check for amounts of albumin (protein). A urine test for protein can be done on a sample of urine collected randomly (usually the first time you urinate in the morning), a sample collected over 24 hours, or a sample collected over a specific period, such as 4 hours or overnight.
No preparation is needed for this test, but results can be affected by factors such as high blood sugar levels, recent exercise, urinary tract infections, high blood pressure, heart failure, or a high fever during an infection.
Abnormal results differ slightly among the three different types of urine samples.1
| Results | 24-hour urine sample | Timed urine sample | Random urine sample |
|---|---|---|---|
| Milligrams of protein per 24 hours | Micrograms of protein per minute | Micrograms of protein per milligram of creatinine | |
Normal |
Less than 30 |
Less than 20 |
Less than 30 |
Tiny amounts of protein (microalbuminuria) |
30–299 |
20–199 |
30–299 |
High protein (macroalbuminuria) |
300 or more |
200 or more |
300 or more |
Because the amount of protein lost through urine varies, 2 of 3 urine samples within a 3- to 6-month period need to show abnormal results for a diagnosis of diabetic kidney disease (nephropathy).
Credits
| Author | Caroline Rea, RN, BS, MS |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Pat Truman, MATC |
| Primary Medical Reviewer | Michael J. Sexton, MD - Pediatrics |
| Specialist Medical Reviewer | Stephen LaFranchi, MD - Pediatrics and Pediatric Endocrinology |
| Last Updated | July 28, 2008 |
