Chronic Kidney Disease

Chronic kidney disease (CKD) is not diagnosed from one abnormal creatinine result. It means that reduced kidney function or kidney damage has persisted for at least 3 months. CKD is present when either of the following is documented for 3 months or longer: - an estimated glomerular filtration rate (eGFR) below 60 mL/min/1.73 m² - a marker of kidney damage, such as an albumin-to-creatinine ratio (ACR) of at least 3 mg/mmol, even when the eGFR is normal The kidneys regulate filtration, fluid volume, electrolytes, acid-base balance, erythropoietin production, and activation of vitamin D. As functioning nephrons are lost, the remaining nephrons initially increase their workload. This compensatory hyperfiltration can preserve the eGFR for a time, but sustained pressure damages glomeruli and allows albumin to leak into urine. Sodium and water retention then contribute to hypertension and edema, while reduced erythropoietin production contributes to anaemia. The same feedback cycle can worsen kidney injury: reduced filtration promotes fluid and metabolic waste accumulation, and hypertension increases intraglomerular pressure. Albuminuria is therefore more than a laboratory abnormality; it signals glomerular injury and predicts increased...