What is kidney function?
Kidney function refers to the key physiological roles of the kidneys in maintaining homeostasis, primarily including the excretion of metabolic waste, regulation of electrolyte balance, maintenance of acid-base balance, and hormone secretion . Healthy kidneys ensure normal metabolic function and also significantly impact blood pressure and bone health.
The Core Role of Kidney Function
Excretion of metabolic waste.
The kidneys produce urine to excrete excess metabolic waste products such as urea, creatinine , and uric acid from the body. Excessive accumulation of these substances can lead to poisoning or organ damage.
Regulating water and electrolyte balance2.
The kidneys maintain the body’s water and electrolyte balance by regulating urine volume and the concentration of ions such as sodium, potassium, and calcium in the urine. For example, when the body is dehydrated, the kidneys concentrate urine to reduce water loss.
Maintaining acid-base balance3.
The kidneys maintain the blood pH between 7.35 and 7.45 by excreting acidic substances (such as hydrogen ions) or reabsorbing alkaline substances (such as bicarbonate), thus preventing acidosis or alkalosis .
Hormone secretion and regulatory function.
Erythropoietin (EPO) : Stimulates the bone marrow to produce red blood cells, preventing anemia .
Renin : It participates in blood pressure regulation and affects vasoconstriction and blood volume through the renin-angiotensin system.
Active vitamin D conversion : helps calcium absorption and maintains bone health.
II. Common Indicators for Assessing Kidney Function
Blood test:
Creatinine (Cr) : Elevated creatinine levels may indicate decreased kidney function.
Blood urea nitrogen (BUN) : reflects protein metabolism and kidney excretion capacity.
Estimating glomerular filtration rate (eGFR) : Assessing kidney filtration efficiency by taking into account factors such as age, sex, and creatinine levels.
urine test2.
Proteinuria : Proteinuria may be a sign of glomerular damage.
Urine sediment : Detects red blood cells, white blood cells, or casts to aid in the diagnosis of nephritis or infection.
Imaging examination3.
Ultrasound and CT scans can be used to observe the morphology of the kidneys and screen for stones , tumors , or structural abnormalities.
Common Diseases Affecting Kidney Function
Chronic kidney disease (CKD)1.
Long-term hypertension , diabetes and other conditions can lead to the gradual loss of kidney function. Early symptoms are not obvious, and in the later stages, dialysis or transplantation may be required.
Acute kidney injury (AKI)2.
Caused by infection, drug toxicity, or insufficient blood volume, it manifests as a sudden decrease in urine output and a surge in creatinine, requiring timely intervention.
glomerulonephritis
Immune abnormalities can lead to glomerular inflammation, which may be accompanied by hematuria and edema.
Kidney stones or obstruction
Kidney stones or tumors can obstruct the urinary tract, affecting urine output and leading to hydronephrosis or even loss of kidney function.
How to protect kidney function
Control underlying diseases1.
Manage chronic diseases such as hypertension and diabetes , and monitor blood sugar and blood pressure regularly .
Rational drug use
Avoid long-term abuse of nonsteroidal anti-inflammatory drugs (such as ibuprofen ) and some nephrotoxic drugs such as antibiotics.
Healthy lifestyle
Drink 1.5-2 liters of water daily and avoid high-salt and high-protein diets.
Quit smoking and limit alcohol consumption, exercise moderately, and maintain a healthy weight.
Regular screening4.
High-risk individuals (such as those with diabetes or hypertension) are advised to have their urine routine and kidney function checked annually.
Summary
Kidney function is the cornerstone of life, involving excretion, regulation, and endocrine processes. Early detection of abnormalities (such as foamy urine, increased nocturia, and fatigue) and proactive intervention can slow disease progression. A healthy lifestyle and regular checkups are key to protecting the kidneys.