Kidney and Liver Testing in Diabetes
Yes, patients with diabetes absolutely require regular kidney and liver function tests as part of their standard care.
Required Kidney Function Tests
Both serum creatinine with estimated glomerular filtration rate (eGFR) and spot urinary albumin-to-creatinine ratio (UACR) must be performed annually in all patients with diabetes 1, 2. These tests are non-negotiable components of comprehensive diabetes care.
When to Start Kidney Screening
- Type 1 diabetes: Begin screening 5 years after diagnosis 2
- Type 2 diabetes: Begin screening immediately at diagnosis 2, 3
Frequency of Kidney Monitoring
- Annual testing is the baseline requirement for all patients with diabetes 1
- More frequent monitoring (2-4 times per year) is needed if abnormalities are detected or if the patient has moderate-risk features (eGFR 45-59 or UACR 30-299) 2
- Quarterly monitoring (3-4 times per year) is required for high-risk patients with eGFR <45 or UACR ≥300 2
- Testing may need to be more frequent in patients with known chronic kidney disease or when medications affecting kidney function are changed 1
Required Liver Function Tests
Liver function tests should be performed annually in patients with diabetes 1. This is explicitly listed in the American Diabetes Association's comprehensive medical evaluation table as a component that should be checked "if not performed/available within the past year" 1.
When More Frequent Liver Testing Is Needed
Liver function tests may need to be checked more frequently after initiation or dose changes of medications that affect liver values, including diabetes medications, blood pressure medications, cholesterol medications, or thyroid medications 1.
Additional Required Laboratory Tests
Beyond kidney and liver tests, the annual diabetes evaluation should include 1:
- Lipid profile (total, LDL, HDL cholesterol and triglycerides) - annually
- A1C - at least twice yearly if meeting goals, quarterly if not meeting goals 1
- Serum potassium - in patients on ACE inhibitors, ARBs, or diuretics 1
Critical Pitfalls to Avoid
Do not skip kidney testing even if the patient feels well - diabetic kidney disease can be present at diagnosis in type 2 diabetes, and 6.5% of newly diagnosed patients already have significant urinary albumin elevation 3. Approximately 20-40% of patients with diabetes will eventually develop chronic kidney disease 3.
Do not rely on a single abnormal test - two out of three specimens must be abnormal over a 3-6 month period to diagnose diabetic nephropathy due to significant day-to-day variability 2.
Do not ignore temporary factors that can falsely elevate urinary albumin, including exercise, acute infection, fever, congestive heart failure, marked hyperglycemia, marked hypertension, urinary tract infection, or hematuria 2.
When to Refer to Nephrology
Referral to a nephrologist is indicated when 2, 3:
- eGFR <30 mL/min/1.73 m²
- Continuously increasing urinary albumin levels
- Continuously decreasing eGFR