If a patient is newly discovered to have a high creatinine (stages 2-4 CKD), they cannot be labeled as having CKD unless you know that this is a stable value. Elsewhere in these guidelines we have suggested checking the serum creatinine within 14 days to be sure that the level is not rising. This only applies if the patient is well and other results (especially potassium) not worrying.
Initial assessment of a high creatinine (low eGFR)
Acute renal failure - a decline in renal function over hours or days - needs urgent assessment.
Sometimes the cause is immediately apparent (e.g. bladder outflow obstruction or drugs) and quickly rectifiable. If not, urgent hospital assessment is almost always required. Refer according to local protocols.
Slower rates of deterioration may need specialist assessment: referral guidelines are
- NICE suggests these rates of GFR loss:
- Loss of GFR of 5ml/min/1.73m2 over a year or less
- Loss of GFR of 10ml/min/1.73m2 over 5 years or less
- Or if Stage 4 CKD is reached (GFR<30mls/min/1.73m2)
- Sooner if there is proteinuria and/or haematuria - more info
Information for patients
Most patients who are newly discovered to have poor kidney function tests have an old problem which is changing slowly. It is important to spot those whose tests are changing more quickly. In many cases, changes in medicines or other simple changes will be enough to put things right, but others may need further investigations and specialist treatment.