In many Chronic Kidney Disease(CKD) patients, previous renal disease or other underlying diseases are already known，with a small number presents with CKD of unknown cause. In these patients, a cause is occasionally identified retrospectively.
It is important to differentiate Chronic Kidney Disease(CKD) from acute renal failure (ARF) because ARF can be reversible. Abdominal ultrasound is commonly performed, in which the size of the kidneys are measured. Kidneys with Chronic Kidney Disease(CKD) are usually smaller (< 9 cm) than normal kidneys with notable exceptions such as in diabetic nephropathy and polycystic kidney disease. Another diagnostic clue that helps differentiate Chronic Kidney Disease(CKD) and ARF is a gradual rise in serum creatinine (over several months or years) as opposed to a sudden increase in the serum creatinine (several days to weeks). If these levels are unavailable (because the patient has been well and has had no blood tests) it is occasionally necessary to treat a patient briefly as having ARF until it has been established that the renal impairment is irreversible.
In chronic renal failure treated with standard dialysis, numerous uremic toxins accumulate. These toxins show various cytotoxic activities in the serum, have different molecular weights and some of them are bound to other proteins, primarily to albumin. Such toxic protein bound substances are receiving the attention of scientists who are interested in improving the standard chronic dialysis procedures used today.
