Chronic Kidney Disease Pathway Document Description Presented ...

The diagnosis of CKD is made by assessment of kidney function using estimated
Glomerular Filtration Rate (eGFR). eGFR is calculated from serum creatinine
levels, but depends on the method of creatinine assay used by each pathology
department. Therefore independent calculations of eGFR from previous
creatinine results will not give reliable results, as a correction factor needs to be
applied for the method used by Dudley group of hospitals pathology dept.
There is no need for 24-hour urine collection to measure creatinine clearance in
primary care.
The method for calculating eGFR is the 4-variable MDRD formula:
eGFR (mL/min/1.73m 2 )= 186 x [Serum Creatinine (umol/L) x 0.0113] -1.154 x
Age(years) -0.203 (x 0.742 if female) and 1.21 if African Caribbean.
An online calculator can be downloaded from:
http://www.renal.org/eGFRcalc/GFR.pl
N.B. The 4-variable MDRD formula:
• Is suitable for adults only (>17 years of age)
• Results are unreliable for eGFR > 60 mL/min/1.73m 2 .
• Results will NOT reflect true GFR if patient is receiving dialysis therapy.
• The formula has not been validated for Asian people.
• Results may deviate from true GFR values with extremes of body
composition, dietary intake or severe liver disease.
• The formula has NOT been validated for drug dosing. Use the Cockcroft
and Gault formula
Diagnosis of CKD should be made during a period of wellness by
measurement of eGFR.
Advise the person not to eat meat for at least 12 hours before the eGFR blood
test.
If the eGFR is < 60 mls/min then the guidance in this pathway should be followed
to exclude acute renal failure.
A diagnosis of renal impairment should not be made on the basis of
one result; at least 2 results should be considered which should be at
least 3 months apart.
If both of the results are< 60 mls/min then the patient should be considered to
have CKD and be added to the practice register. The patient should then be
managed following the guidance in this pathway.
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