The kidney plays an important role in the body. In addition to removing wastes and fluid, the kidneys perform other important jobs. It regulates the body water and other chemicals in the blood such as sodium, potassium, phosphorus and calcium. It removes drugs and toxins introduced into the body. It releases hormones into the blood to regulate blood pressure, generation of red blood cells and promotion of healthy bones.

Large studies in the United States (NHANES) indicated that more than 10 percent of adults have CKD. High risk groups include those with diabetes, hypertension and family history of kidney disease. Early detection can help prevent the progression of kidney disease to kidney failure. Glomerular filtration rate (GFR) is the best estimate of kidney function. Additionally, persistent proteinuria indicates the presence of CKD. Three simple tests can detect CKD: blood pressure, urine albumin and serum creatinine.

Cystatin C

Many studies showed that serum levels of cystatin C estimate GFR better than serum creatinine alone. Recent studies have clearly demonstrated that cystatin C is a better predictor of adverse events in the elderly, including mortality, heart failure, bone loss, peripheral arterial disease and cognitive impairment, than either serum creatinine or estimated GFR. These findings may be because cystatin C is a better filtration marker than creatinine. An alternative explanation is that factors other than GFR that affect serum levels of creatinine and cystatin C differentially confound the relationships between these measures and outcomes (see Scientific literature cystatin C).

Causes of CKD

The two main causes of chronic kidney disease are diabetes and high blood pressure, which are responsible for up to two-thirds of the cases. Diabetes causing damage to many organs in the body, including the kidneys and heart, as well as blood vessels, nerves and eyes.
If hypertension is uncontrolled, or poorly controlled, high blood pressure can be a leading cause of heart attacks, strokes and chronic kidney disease. Also, chronic kidney disease can cause high blood pressure.

Other conditions that affect the kidneys are glomerulonephritis, a group of diseases that cause inflammation and damage to the kidney's filtering units. These disorders are the third most common type of kidney disease. Further, inherited diseases, such as polycystic kidney disease, causing large cysts to form in the kidneys and damage the surrounding tissue, Lupus and other diseases that affecting the body's immune system, Obstructions caused by problems like kidney stones, tumours or an enlarged prostate gland in men and repeated urinary infections can cause CKD.

Symptoms of CKD

Most people may not have any severe symptoms until their kidney disease is advanced. However, one may notice that one feel more tired and have less energy. Further symptoms are trouble concentrating, poor appetite, trouble sleeping, muscle cramping at night, swollen feet and ankles, puffiness around your eyes, especially in the morning, dry, itchy skin or need to urinate more often, especially at night.

Anyone can get chronic kidney disease at any age. However, some people are more likely than others to develop kidney disease.
 

SCIENTIFIC Literature Cystatin C

- Séronie-Vivien S et al. Clin Chem Lab Med. 2008 ;46(12)

- Madero M et al. Curr Opin Nephrol Hypertens. 2006;15(6)

- Laterza OF et al. Clin Chem. 2002; 48(5)

- Shlipak MG et al. Ann Internal Med. 2006;145(4)

Further Readings Chronic Kidney Disease

- US National Kidney Foundation

            FAQ about GFR estimates (pdf 972kb)

- World Kidney Day

- International Society of Nephrology (ISN)

- International Federation of Kidney Foundations (IFKF) - Weblinks