Diagnosis of Kidney Disease
In many CKD patients, previous renal disease or other underlying diseases are already known. A small number present with CKD of unknown cause. In these patients, a cause is occasionally identified retrospectively.
It is important to differentiate CKD from acute renal failure (ARF) because ARF can be reversible. Abdominal ultrasound, in which the size of the kidneys is measured, is commonly performed. Kidneys with 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 CKD from 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.
Chronic kidney disease usually causes no symptoms in its early stages. Only lab tests can detect any developing problems. Anyone at increased risk for chronic kidney disease should be routinely tested for development of this disease.
- Urine, blood, and imaging tests (X-rays) are used to detect kidney disease, as well as to follow its progress.
- All of these tests have limitations. They are often used together to develop a picture of the nature and extent of the kidney disease.
- In general, this testing can be performed on an outpatient basis.