Times of India
28 October 2010
By Durgesh Nandan Jha
New Delhi, India

Marker Identifies Disease 10 Yrs Before Onset
A new technique for early detection of Chronic Kidney Disease (CKD) could save many lives in future. With the help of a multi–marker panel of proteins and hormones, individuals at a greater risk of developing the disease can be identified up to 10 years before its clinical onset. By the time CKD is usually diagnosed, it is stage III and IV and half of the kidney is already damaged.

Doctors say it will be possible to start treatment and make lifestyle changes at an early stage with the help of this finding. According to a doctor, the new biomarkers can be tested in a single blood sample. The biomarkers are homocysteine, a marker for atherosclerosis; aldosterone, a hormone that affects salt handling by the kidneys; and BNP, which is involved in maintenance of blood pressure and volume.

The biomarkers have been identified with the help of a research carried out on more than 2,300 persons with normal kidney functions. The subjects were tested for over a period of 10 years to find the biomarkers that can identify high–risk individuals. The study has been published in the latest edition of the Journal of the American Society of Nephrology.

According to Dr S C Tewari, director of nephrology and renal transplant at the Fortis Institute for Renal Sciences, the new biomarkers can be tested in a single blood sample. "It is a revolutionary finding and can help in saving the life of many patients," said Tewari. He said serum creatinine, the primary biomarker for CKD is insensitive to early perturbations in renal function, particularly in patients without overt clinical CKD.

CKD affects 16% of the Indian population. It is associated with metabolic abnormalities and bone disease and is also an important risk factor for peripheral vascular disease, cardiovascular disease, stroke, all of which cause mortality. Hypertension and diabetes are key risk factors but do not fully help in identifying individuals at risk of developing CKD.

Said Dr Sandeep Mahajan, nephrologist, AIIMS, "All the existing diagnostic tests including eGRF and CKD–EPI are creatinine–based. The identification of the disease through this process is delayed and the new finding – if validated on Indian population – can bring a revolutionary change in treatment of CKD. We can use certain drugs and lifestyle modification such as weight control and dietary changes to prevent the disease."

He added the present results require further replication and testing in clinical trial settings as well as in costeffectiveness settings before being brought into the clinical arena.

Early Diagnosis Can Save Lives
Chronic Kidney disease (CKD)
CKD is associated with metabolic abnormalities and bone disease and is also an important risk factor for peripheral vascular disease, cardiovascular disease, stroke – all of which can be fatal 16 % suffers of Indian from population CKD

Available medical test
Glomerular Filtration Rate (GFR) is based on serum creatinine measurement. Half the kidney is damaged in most cases by the time the disease is diagnosed, say doctors

Biomarkers
Predict CKD 10 years before its clinical onset

New CKD biomarkers
validated through research

Homocysteine
Protein which is the marker for atherosclerosis (thickening of arteries)

Aldosterone
Hormone that affects salt handling by kidneys

B–type natriuretic peptide | Indicates heart damage in patients

Benefits of early diagnosis
Certain medicines and lifestyle modification like weight control and dietary changes at an early stage can prevent the disease or delay the prognosis These new biomarkers were developed after prolonged research on 2,300 patients of American origin. Doctors say replication on Indians and cost–effectiveness needs to assessed