Chronic kidney disease (CKD) is a type of long-term kidney disease, defined by the sustained presence of abnormal kidney function and/or abnormal kidney structure. To meet the criteria for CKD, the abnormalities must be present for at least three months. Early in the course of CKD, patients are usually asymptomatic, but later symptoms may include leg swelling, feeling tired, vomiting, loss of appetite, and confusion. Complications can relate to hormonal dysfunction of the kidneys and include high blood pressure (often related to activation of the renin–angiotensin system), insulin resistance, bone disease, and anemia. Additionally CKD patients have markedly increased cardiovascular complications with increased risks of death and hospitalization. CKD can lead to end-stage kidney failure requiring kidney dialysis or kidney transplantation.
Causes of chronic kidney disease include diabetes, high blood pressure, glomerulonephritis, and polycystic kidney disease. Risk factors include a family history of chronic kidney disease. Diagnosis is by blood tests to measure the estimated glomerular filtration rate (eGFR), and a urine test to measure albumin. Ultrasound or kidney biopsy may be performed to determine the underlying cause. Several severity-based staging systems are in use.
