To the Editor: The Australasian Creatinine Consensus Working Group has issued an important statement1 that highlights the perils of relying on serum creatinine concentration alone to estimate kidney function. However, the suggestion that the recommended eGFR (estimated glomerular filtration rate) “is not appropriate for use . . . [in certain groups, such as] Aboriginal and Torres Strait Islander populations” and that “GFR should be measured directly” in such populations is poorly worded and clinically inappropriate.

The two most commonly used formulas for eGFR calculation (the Cockroft–Gault and MDRD [Modification of Diet in Renal Disease] equations) are both derived from studies in US subjects, with a correction factor added for African-Americans.2,3 Concerns have recently been raised about other ethnic groups.4 As neither formula has been validated in any specific Australian majority or minority group, to recommend exclusion of Aboriginal and Torres Strait Islander populations without data is inappropriate.

In the Northern Territory, rates of kidney disease in Indigenous Australians are 20–30 times those in the white population. In addition, Indigenous Australians have limited access to basic health care, let alone “direct measurements of GFR”. We believe that, until data are available on the validity of the MDRD formula for specific minority groups, the best clinical care can be delivered by measuring the serum creatinine concentration and calculating eGFR (using the MDRD equation) in all Australians. We have been using this approach for over 2 years.

Therefore we suggest the following alternative to the Working Group’s recommendation: