Isolated estimated glomerular filtration rate (eGFR) measurements in the quality framework are failing to distinguish between patients with stable and unstable CKD, Dr Donal O’Donoghue told GP.
Proteinuria and serial eGFR measurements that calculate rate of change should be used instead to pick out the minority of patients likely to progress to renal failure, he said.
His remarks follows a report that these measurements are likely to be added to the quality framework (GP, 16 March).
‘The eGFR is not a perfect measure — 90 per cent of people are in 30 per cent of their true eGFR,’ he said.
But because improved biochemical methods to determine kidney function are years away, GPs can use additional measures to reduce the number of patients with stable CKD being referred. GPs should not automatically refer a patient with low eGFR to secondary care, Dr O’Donoghue said.
‘What we’ve seen across the country is an increase in inappropriate referrals and appropriate referrals,’ he said. ‘We’ve now got a system where people with an eGFR below 60 are being flagged, so that’s leading to an increased awareness of CKD.
‘When unexpected CKD is identified in that way, then it’s important to consider why the patient may have a low eGFR.’
GPs should compare eGFR readings to previous serum creatinine measurements, said Dr O’Donoghue, who conceded rate of change could be difficult to determine because of variation in the type of assay used.
GPs should also check whether a patient was on medications, such as NSAIDS, or had comorbidities that can lower eGFR.
‘It’s good medical practice that if you’ve got a case of CKD, the next thing is proteinuria.
‘If there’s a normal proteinuria, and no change in eGFR, the appropriate care is vascular disease management, which is done best in primary care,’ he added.
Dr Lawrence Goldberg, lead consultant at the Sussex Kidney Unit and member of the Renal Association executive committee, said the Renal Association and the Royal College of Physicians had called for proteinuria and serum creatinine measurements to be included in the next quality framework review.
Since inclusion of CKD in the quality framework, his unit had seen a 50 per cent increase in referrals, said Dr Goldberg. In a third of cases, letters are sent to the GP with instructions for management in primary care.
‘It’s a new area for primary care to deal with and there’s a learning curve. But as time goes on and GPs get more confident, there’s no need to refer.’