Chronic Kidney Disease

A single elevated serum creatinine does not establish chronic kidney disease. CKD means an abnormality of kidney structure or function has persisted for at least 3 months and has implications for health. That time requirement separates chronic disease from acute kidney injury and prevents a transient change during dehydration, infection, obstruction, or nephrotoxin exposure from being mislabeled as permanent disease. The two tests that identify CKD are a blood estimated glomerular filtration rate (eGFR) and a urine albumin-to-creatinine ratio (uACR). Persistent eGFR below 60 mL/min/1.73 m2 meets the criterion even when urine albumin is not elevated. Conversely, persistent uACR of at least 30 mg/g identifies kidney damage even when eGFR remains above 60. Using eGFR alone therefore misses albuminuric CKD with preserved filtration. A patient may have no symptoms for years. The kidneys can lose substantial filtration before the patient notices fatigue, nausea, edema, or changes in urination. This is why a nurse should not use the absence of symptoms to dismiss an abnormal eGFR or uACR. Diabetes and hypertension are major causes and risk markers. In the United States,...