The diagnosis of diabetic nephropathy depends mostly on urinalysis. The most important finding is documenting the presence of albumin in the urine

The diagnosis of diabetic nephropathy depends mostly on urinalysis. The most important finding is documenting the presence of albumin in the urine:^[1][2]

• Screening for albuminuria is done with a routine dipstick urinalysis.
• However, routine dipsticks do not rule out microalbuminuria.
• Hence, if the test is positive, a 24-hour urine sample for quantifying the amount of protein should be done.
• However, if the test is negative, a radioimmunoassay for albumin should be done and repeated every year if the initial result is negative.
• Conditions such as heart failure, uncontrolled hypertension, UTI and an acute febrile illness increase the albumin excretion in the urine and hence, testing for albuminuria should not be performed during these conditions.^[3]
• The albumin to creatinine ratio should also be measured in a morning urine sample, a 24-hour or an overnight sample.
• In the case of an abnormal urine albumin to creatinine ratio (more than 30 mg/ g Cr), test should be repeated once or twice over a period of few months for consistency of the results.
• Estimated GFR (eGFR) is often calculated at the time of screening to document and/or stage chronic kidney disease (CKD).
• If retinopathy is present along with albuminuria, the albuminuria is highly attributed to diabetic nephropathy.
• New genetic markers are being studied for diabetic nephropathy. These markers are being determined in order to facilitate an early identification and management of patients at a high risk of developing diabetic nephropathy.^[2]