Millions of people in the UK are needlessly suffering from advanced kidney disease, because of a ‘blind spot’ in current testing methods. The traditional test used by the NHS to identify kidney dysfunction, measures the level of a waste product (Creatinine), which is only raised when up to 60% of the kidney has already been damaged. This damage is irreversible, with dialysis or transplant the only available therapies.
As kidney disease progresses, waste builds up in the blood which can have a significant impact on other key areas of the body; impairing heart health, weakening bones, reducing immune response and damaging the central nervous system. If left unchecked, CKD can cause kidney failure and death.
With early detection, the progression of CKD can be prevented; in response to this the National Institute for Health and Care Excellence, has drafted new guidance for doctors to improve diagnosis and identify kidney dysfunction in the earliest stages. The health watchdog makes it clear that a highly sensitive test for the biomarker Cystatin C, should be used alongside the traditional creatinine test, for more accurate and earlier identification of kidney function deterioration.
Cystatin C is a protein produced by the body at a constant rate, its small molecular weight allows it to be completely broken down and removed by the kidneys; levels therefore, remain steady if the kidneys are working efficiently and the glomerular filtration rate (GFR) is normal. If kidney function deteriorates, Cystatin C concentrations rise.
Testing for cystatin c means doctors can pick up on even the smallest changes in GFR, identifying a drop in kidney function at the earliest opportunity. Once a problem has been spotted early it can be managed through medication and/or changes to diet and lifestyle, preventing chronic kidney disease from occurring.
Around 2 million adults in England have CKD – but as it is largely asymptomatic and often undiagnosed, it is thought a further 1 million could also be suffering from the advanced stages of the disease. Dr Gilbert Wieringa, Consultant Biochemist at Bolton NHS Foundation Trust, a keen advocate of the test commented:
“I welcome the fact that NICE now recognises Cystatin C as a key biomarker in the differential diagnosis of CKD. The ready availability of this blood test ensures the right treatment can be started for the right patient in the right time in turn helping to prevent or delay progression of CKD, reducing or delaying complications, and reducing the risk of cardiovascular disease. It provides a key example where investment in a diagnostic test helps reduce far greater cost burdens of managing secondary complications further down the line”
NICE says that while using the cystatin c test will increase the cost of diagnosis “accuracy is expected to improve and fewer people are expected to require treatment and monitoring”.
Dr Peter FitzGerald, MD at UK Biotech firm Randox, which has created a cystatin C test for use in every standard hospital lab in the UK, believes the new diagnostic method could have a significant impact on the financial burden of CKD on the NHS:
“CKD is closely linked with diabetes, obesity, stoke and cardio vascular disease – as we see these conditions increase across the UK, so too will the prevalence of CKD, but if we can catch kidney function damage early, we can prevent CKD and prevent the need for expensive medical interventions such as dialysis, the cost of which per patient, per year is around £31,000. Needless to say, it also comes at considerable personal expense, but this does not have to be the way.”
NICE estimates that up to 20% of the current CKD population may not have needed medication, if the new testing method was introduced and says “savings are expected at a local level as a result of this change.”