Health-Care Provider Information
Stages of Chronic Kidney Disease (CKD)
- CKD is defined as abnormalities of kidney imaging, urinalysis, or function (eGFR <60 mls/min/1.73m2) for greater than 3 months.
- Based on eGFR and urine albumin-creatinine ratio.
- Both must be done in order to help guide diagnosis, management and predict risk of progression. Imaging and kidney biopsy may also be required for diagnosis, management, and prognosis.
- Please refer to the heat map at: Chronic Kidney Disease Stages
- The higher the ACR, the greater the chance of progression of the chronic kidney disease.
- Best calculated by the CKD-EPI equation. Can use qxmd.com
- If reported <60 mls/min/1.73m2, should be repeated within 1 to 2 weeks to ensure it is not declining rapidly and if not, repeated again after 3 months to determine if persistent.
- Interpret with caution in the very elderly, those with morbid obesity, those with low body mass index, patients who have amputations and in pregnancy.
- Requires a correction factor for African American ethnicity – multiple eGFR by 1.21 for correct value.
- Drugs that inhibit the tubular secretion of creatinine (such as trimethoprim, gemfibrozil, cimetidine) can affect eGFR accuracy.
- Do not use eGFR in acute kidney injury.
Urine albumin-creatinine ratio (ACR)
- Spot urine collection, early morning specimen is best but any time of day is okay.
- 2 of 3 tests must be greater than 2 mg/mmol if diabetic or greater than 3 mg/mmol if not diabetic.
- Do NOT do a urine for ACR when:
- Blood sugars are very high – i.e. Diabetes is poorly controlled.
- Hypertension is poorly controlled.
- The patient has an infectious illness.
- Congestive heart failure is not controlled.
- The patient has her menses.
- The patient has been vigorously exercising in the past 48 hours.
Kidney Failure Risk Equation
- This tool identifies patients who are at increased risk of progression to end-stage kidney disease, especially when the eGFR is 30 to 60 mls/min. The equation requires age, sex, eGFR and ACR.
- The results of this calculation stratify patients into no current risk, low risk, intermediate risk, and high risk for progression.
- The KFRE can be accessed at: kidneyfailurerisk.com or at qxmd.com
Treatment Tips for People with Diabetes and CKD
- All of these treatments are an attempt to decrease the urine ACR in order to decrease progression of kidney disease.
- Control BP: Target BP is <130/80 mmHg for most people. Multiple comorbidities and the frail elderly will have a target BP of 140/90 mmHg.
- Control Blood sugar: Target A1c is 7% or less for most people. Multiple comorbidities and the frail elderly will have a target A1c of 7.5 to 8%.
- Salt restriction: 1500 mg/day.
- Protein restriction: 1 gm/kg/day.
- Smoking cessation.
- Control weight and/or modest weight loss.
- Assess for sleep apnea.
When to Refer to Nephrology
- Acute kidney failure
- eGFR <60 mls/min/1.73m2 with proteinuria and/or microscopic hematuria
- Progressive decline in eGFR
- Persistent proteinuria (2 of 3 urine samples)
- Unexplained hematuria
- Hereditary or unknown cause of CKD
- Inability to achieve treatment targets or other difficulties in management of the CKD patient.
- If in doubt, call LINK Nephrology through System Flow Coordination Centre.