In Stage 1 CKD kidney function is normal but there is other evidence of kidney disease. Stage 2 CKD is mildly reduced kidney function, GFR 60-89mls/min/1.73m2 Both stages require other evidence of kidney disease, for example:
- Proteinuria or haematuria
- A genetic diagnosis of kidney disease (e.g. known to be have a disease such as polycystic kidney disease)
- Evidence of structurally abnormal kidneys (e.g. reflux nephropathy, renal dysgenesis).
Rememember that eGFR is an estimate (more info on eGFR). Was an appropriate correction for black race made?
Creatinine and eGFR in an individual are usually quite stable. Deteriorating renal function needs rapid assessment. Further information on initial assessment of renal impairment and deteriorating renal function. Note that CKD staging and management outlined below are only applicable to stable renal function.
Assessment and management of Stages 1+2 CKD.
Almost all patients with stages 1 and 2 CKD can be appropriately managed in primary care. The aim is to identify individuals at risk of progressive renal disease, and reduce associated risks.
- Risk of cardiovascular events and death is substantially increased by the presence of CKD; at CKD 1-2, particularly by proteinuria. The risk of cardiovascular death is (on average) much higher than the risk of needing dialysis or a renal transplant.
- Some patients need further investigation where there are indications that progression to end stage renal failure (Stage 5) may be likely. Pointers to progression of renal disease are:
- Proteinuria - the risk is graded, but a common cut-off for investigation is ACR>70 or PCR>100
- Haematuria of renal origin
- Declining GFR - more info
- Young age
- Long term monitoring of renal function and other parameters is indicated.
Initial assessment | Management
Initial assessment of stages 1 and 2 CKD
The aim is to identify individuals at risk of progressive renal disease, and to reduce associated risks.
- Patients have normal or near-normal GFR, but have other evidence of renal disease.
- If assessment is precipitated by a first discovery of elevated creatinine, it is important to be certain that the value is stable. Maybe there are previously recorded values? If not, and the patient is well, repeat test within 14 days. Ideally this sample should be taken after a period of at least 12h without meat consumption, and the sample must get to the lab or be separated the same day. Deteriorating renal function needs rapid assessment.
- Undertake further assessment as shown below for long term management.
- Where haematuria or proteinuria are present but referral is not indicated, annual monitoring, with later referral if there is evidence of progression (see below), is appropriate.
Management of Stages 1 and 2 CKD
- 12 monthly estimation of
- Creatinine - consider referral/advice if significant progression. A significant change in eGFR has been variously defined as a short-term eGFR fall of >15% or [creatinine] rise >20%; or more recently (NICE guideline) a loss in GFR over 1y of 5ml/min, or a loss of GFR in 5y of 10ml/min. More on deteriorating function
- Urinar y protein for ACR or PCR. Note thresholds; ACR 30 or PCR 50 for more stringent blood pressure targets (and suffix 'p' on CKD stage), and ACR 70 or PCR 100 for specialist referral/discussion. More on proteinuria
- Blood pressure - 140/90 max (130-139/90), or 130/80 max (120-129/80) for patients with proteinuria: urinary ACR>30 or PCR>50. More on hypertension
- Cardiovascular risk - advice on smoking, exercise and lifestyle. Consider cholesterol lowering therapy if already have macrovascular disease, or if estimated 10 year risk of cardiovascular events =/>20%. More on CV risk in CKD
Patient info - Stages 1 and 2 CKD
Stage 1 CKD is kidney disease with normal kidney function. In Stage 2 CKD function is 60-90%. Most patients with stages 1 and 2 CKD just need occasional testing to be sure things are no different, but a few patients need further investigation because there are pointers to a disease that could benefit from treatment or lead to serious further trouble.
Further information about blood tests and kidney function from the Edinburgh Renal Unit website.