Monitoring protocol if unstable chronic kidney disease (CKD)

if a decline in estimated glomerular filtration rate (eGFR) is seen

• then eGFR is repeated three times over a period of at least 90 days (1)
  • a significant eGFR decline is indicated if there is more than a (1,2):
    • 5 mL/min/1.73 m2 decrease within 1 year, or
    • 10 mL/min/1.73 m2 decrease within 5 years
      
• Defining progression (3)
  • define accelerated progression of CKD as:
    • a sustained decrease in GFR of 25% or more and a change in GFR category within 12 months
    • or a sustained decrease in GFR of 15 ml/min/1.73 m2 per year
      
      
  • take the following steps to identify the rate of progression of CKD:
    • obtain a minimum of 3 GFR estimations over a period of not less than 90 days
    • in people with a new finding of reduced GFR, repeat the GFR within 2 weeks to exclude causes of acute deterioration of GFR- for example, acute kidney injury or starting renin-angiotensin system antagonist therapy
      • if a large decline in eGFR is seen (25% or more)
        • then repeat eGFR within 2 weeks to exclude acute kidney injury (2)
          
          
  • be aware that people with CKD are at increased risk of progression to endstage kidney disease if they have either of the following:
    • a sustained decrease in GFR of 25% or more over 12 months or
    • a sustained decrease in GFR of 15 ml/min/1.73 m2 or more over 12 months

Risk factors associated with CKD progression

• cardiovascular disease
• proteinuria
• acute kidney injury
• hypertension
• diabetes
• smoking
• African, African-Caribbean or Asian family origin
• chronic use of NSAIDs
• untreated urinary outflow tract obstruction

Notes:

• 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 (2)
  
  
• consider the person's baseline eGFR and the lifetime likelihood, if they continued the same rate of decline, that they would eventually reach an eGFR level that would require renal replacement therapy
  • for example, a rate of decline of 3 mL/min/1.73 m2 per year would be of greater concern in a person of 40 years of age with a baseline eGFR of 30 mL/min/1.73 m2 than in a person of 70 years of age with a baseline eGFR of 60 mL/min/1.73 m2 (1)
    
    
• detect acute kidney injury by using any of the following criteria (4):
  • a rise in serum creatinine of 26 micromol/litre or greater within 48 hours
  • a 50% or greater rise in serum creatinine known or presumed to have occurred within the past 7 days
  • a fall in urine output to less than 0.5 ml/kg/hour for more than 6 hours in adults and more than 8 hours in children and young people
  • a 25% or greater fall in eGFR in children and young people within the past 7 days
    
    
• when the laboratory reports only that the person's eGFR exceeds their reference range (for example, they only report an eGFR as greater than 60 mL/min/1.73 m2)
  • then suspect a significant deterioration in renal function (such as acute kidney injury) if the person's serum creatinine increases greater than 1.5-fold

Reference:

• CKS - chronic kidney disease - not diabetic (Accessed 28/2/14)
• The Renal Association - initial assessment of a high creatinine (low eGFR) (Accessed 28/2/14)
• NICE (August 2021). Chronic kidney disease: assessment and management
• NICE (August 2013). Acute kidney injury - Prevention, detection and management of acute kidney injury up to the point of renal replacement therapy