OVERVIEW

What is chronic glomerulonephritis?

Chronic glomerulonephritis, abbreviated as chronic nephritis, is caused by various factors and consists of multiple types. It can occur at any age but predominantly affects young and middle-aged males^[1].

It has an insidious and slow onset, with basic clinical manifestations including hematuria, proteinuria, hypertension, and edema. It may be accompanied by varying degrees of renal dysfunction and can progress to chronic renal failure^[1].

Treatment primarily involves medication, and the prognosis depends on the severity of the condition and whether effective treatment measures are taken^[1].

Is chronic glomerulonephritis common?

Chronic glomerulonephritis is a common and frequently occurring disease in China^[1], but there is no latest authoritative data on its specific incidence rate.

What are the types of chronic glomerulonephritis?

Based on different renal pathological types, this disease can be classified into:

• Mesangial proliferative glomerulonephritis;
• Mesangiocapillary glomerulonephritis;
• Membranous nephropathy and focal segmental glomerulosclerosis, among others^[1].

SYMPTOMS

What are the common manifestations of chronic glomerulonephritis?

The disease has an insidious onset and progresses slowly. Early-stage patients may have no symptoms, only presenting with fatigue, tiredness, lower back pain, and decreased appetite. Edema may or may not be present, with mild swelling of the eyelids, face, and lower limbs being more common. Blood pressure may be normal or slightly elevated. Laboratory tests may reveal mild urinary abnormalities (proteinuria, hematuria)^[1,2].

This condition may persist for years or even decades, after which kidney function gradually deteriorates, leading to corresponding clinical manifestations such as anemia, malignant hypertension (a sharp rise in blood pressure within a short period, accompanied by symptoms like headache, dizziness, visual disturbances, and difficulty breathing), retinal hemorrhage, persistent systemic edema, and ultimately kidney failure^[1].

What serious consequences can chronic glomerulonephritis cause?

If chronic glomerulonephritis is not treated promptly, it will eventually progress to chronic kidney failure^[1].

CAUSES

What causes chronic glomerulonephritis?

Only a small number of chronic nephritis cases result from the progression of acute nephritis (either direct continuation or recurrence after clinical recovery for several years). The vast majority of chronic nephritis cases develop from primary glomerular diseases with various etiologies^[1].

However, the cause of primary glomerular diseases is not entirely clear and is often associated with immune system abnormalities.

DIAGNOSIS

How do doctors diagnose chronic glomerulonephritis?

Generally, doctors diagnose this condition based on the patient's symptoms, medical history (whether they have or have had other kidney diseases or infections), combined with tests such as urinalysis, urine microalbumin, blood tests, kidney function tests, kidney ultrasound, and kidney biopsy.

What tests are needed to diagnose chronic glomerulonephritis?

If chronic glomerulonephritis is suspected, tests such as urinalysis, urine microalbumin, blood tests, kidney function tests, and kidney ultrasound are usually required. If the cause or pathological type needs to be clarified, a kidney biopsy may also be necessary.

• Urinalysis: A preliminary assessment of whether the urine is normal and whether there is hematuria or proteinuria.
• Urine microalbumin: This test is more precise and accurate than urinalysis, detecting proteinuria that may be missed in routine tests. It better evaluates glomerular filtration function and identifies kidney damage^[3].
• Blood tests: Determine whether there is infection or anemia.
• Kidney function tests: Check for elevated serum creatinine and urea levels, as well as reduced glomerular filtration rate, to assess kidney function and stage the disease.
• Kidney ultrasound: Examine kidney morphology to confirm conditions such as kidney atrophy or masses^[1].
• Kidney biopsy: Determines the pathological type of chronic glomerulonephritis, confirms the specific disease, and helps formulate further treatment plans and prognosis^[1].

What precautions should be taken for a kidney biopsy?

Patients with the following conditions should not undergo a kidney biopsy:

• Significant bleeding tendency;
• Severe hypertension;
• Mental illness or uncooperative behavior;
• Solitary kidney (only one kidney) or small kidney;
• Women should preferably avoid the procedure during menstruation^[4].

Pre-biopsy precautions:

• Practice urinating and defecating in bed before the procedure;
• Train to eat while lying in bed.

Post-biopsy precautions:

• Lie flat for 24 hours. If the condition is stable and there is no visible hematuria, the patient may get out of bed. If visible hematuria occurs, bed rest should be extended until it disappears or significantly improves. Intravenous hemostatic drugs or blood transfusions may be necessary.
• During bed rest, remain quiet and minimize body movements to avoid wound bleeding. Monitor the wound for any bleeding and notify a doctor immediately if it occurs.
• Drink small amounts of water frequently after the procedure to help flush out small blood clots^[5].

What diseases should chronic glomerulonephritis be differentiated from?

1. Secondary glomerular diseases: Such as lupus nephritis, Henoch-Schönlein purpura nephritis, and diabetic nephropathy. These can be distinguished based on corresponding systemic manifestations and specific laboratory tests, such as antinuclear antibody tests and glycated hemoglobin levels^[1].
2. Other primary glomerular diseases:
   • Asymptomatic hematuria and/or proteinuria: Mild chronic glomerulonephritis should be differentiated from asymptomatic hematuria and/or proteinuria, which presents without edema, hypertension, or reduced kidney function^[1].
   • Post-infectious glomerulonephritis: Chronic glomerulonephritis with acute onset due to prior infections (e.g., bacterial infections like streptococcal bronchitis or pneumonia) must be distinguished. The two differ in incubation periods and dynamic changes in serum C3 levels. Additionally, chronic glomerulonephritis progresses chronically without a tendency to resolve^[1].
   • Primary hypertensive kidney damage: Chronic glomerulonephritis with significantly elevated blood pressure should be distinguished from benign arteriolar nephrosclerosis caused by long-term hypertension. The latter shows mild urinary changes (trace to mild proteinuria, possible microscopic hematuria, and casts) and often involves other hypertensive target organ complications (heart, brain)^[1].
   • Chronic pyelonephritis: Typically involves recurrent urinary tract infections, abnormal imaging and kidney function tests, and the presence of white blood cells in urine sediment. Positive urine bacterial cultures help differentiate^[1].

TREATMENT

Which department should I visit for chronic glomerulonephritis?

Nephrology.

How should chronic glomerulonephritis be treated?

The treatment of chronic nephritis should primarily aim to prevent or delay progressive deterioration of renal function, improve or alleviate clinical symptoms, and prevent cardiovascular complications, rather than focusing solely on eliminating red blood cells in urine or mild proteinuria^[1]. The following measures can be taken:

• Aggressively control hypertension and reduce proteinuria: Hypertension and proteinuria accelerate glomerulosclerosis and worsen renal function. Therefore, actively managing hypertension and reducing proteinuria are two critical steps. The treatment goal for hypertension is to maintain blood pressure at an ideal level (<130/80 mmHg). The treatment goal for proteinuria is to reduce it to <1 g/day^[1].
• Limit sodium intake: Chronic nephritis often involves volume-dependent hypertension caused by water and sodium retention. Hypertensive patients should restrict sodium intake (NaCl <6 g/day) and may use appropriate diuretics, such as hydrochlorothiazide^[1].
• Use ACE inhibitors or ARBs: Angiotensin-converting enzyme inhibitors (e.g., captopril, enalapril) or angiotensin receptor blockers (e.g., irbesartan, valsartan) are the first-line treatments for hypertension and/or reducing proteinuria in chronic nephritis. In addition to lowering blood pressure, these drugs also help reduce proteinuria and slow the progression of renal dysfunction. The dosage required to reduce proteinuria is often higher than the standard antihypertensive dose, and adjustments should follow medical advice. Patients with renal insufficiency should be monitored for hyperkalemia, and caution is required when serum creatinine exceeds 264 µmol/L^[1].
• Restrict dietary protein and phosphorus: Patients with renal insufficiency should limit protein and phosphorus intake and follow a high-quality, low-protein diet based on renal function^[1].
• Corticosteroids and cytotoxic drugs: Since chronic nephritis is a clinical syndrome with varying causes, pathological types, severity, clinical manifestations, and renal function, the use of these drugs should be determined based on the specific pathological diagnosis^[1].
• Avoid factors that worsen kidney damage: Infections, fatigue, pregnancy, and nephrotoxic drugs (e.g., aminoglycoside antibiotics, aristolochic acid-containing traditional Chinese medicines) may harm the kidneys and accelerate renal deterioration, so they should be avoided^[1].

DIET & LIFESTYLE

What effects will chronic glomerulonephritis treatment have on the body?

Chronic nephritis is a prolonged condition with slow progression, eventually developing into chronic renal failure. For some patients, this process generally takes over 10 years^[1].

The progression rate varies significantly among individuals, with kidney pathology type being a key factor. However, it is also related to kidney protection, appropriate treatment, and avoidance of aggravating factors.

What dietary precautions should be taken for chronic glomerulonephritis?

Reduce salt intake and avoid high-sodium foods such as pickles and salted duck eggs. Daily salt consumption should not exceed 2–3 g^[6]. Within protein restrictions, choose high-quality proteins like milk, egg whites, lean meat, and fish. Also, limit phosphorus-rich foods such as animal organs and egg yolks^[1].

Ensure adequate carbohydrate intake and supplement vitamins and minerals to meet the body's energy needs. Suitable foods include rice, noodles, lotus root starch, yam, green vegetables, cauliflower, apples, and kiwis^[6].

What lifestyle precautions should be taken for chronic glomerulonephritis?

• Take medications as prescribed by the doctor. Do not reduce, change, or stop medication without permission. Seek medical attention promptly if adverse drug reactions occur.
• Get sufficient sleep, rest adequately, and avoid overexertion^[7].
• Maintain personal hygiene, clean the perineal area daily, and prevent urinary tract infections^[7].
• Stay in a positive mood and relax through preferred activities^[7].

PREVENTION

How to Prevent Chronic Glomerulonephritis?

• Develop good lifestyle habits: Maintain a regular daily routine, engage in moderate physical activity, and exercise appropriately while avoiding excessive fatigue. Strengthen physical fitness and immunity, pay attention to personal and environmental hygiene, maintain a relaxed and cheerful mood, and enhance self-care awareness.
• Guard against bacterial or viral infections: Bacterial or viral infections are the most common causes of acute nephritis, particularly upper respiratory infections, asymptomatic bacteriuria, influenza, pharyngitis, and tracheobronchitis, which may worsen chronic nephritis symptoms. Actively prevent and treat infections, as well as acute nephritis. Reduce the chances of infection, avoid exposure to cold, and prevent illnesses such as colds, purulent tonsillitis, and skin infections.
• Pay attention to diet and nutrition: Patients should avoid high-protein diets, ensure food safety, and consume fresh fruits and natural foods. Follow the principles of variety, balanced combinations, and light, palatable meals.

In summary, once diagnosed, active treatment should be pursued to prevent progressive deterioration of kidney function and delay or avoid the stage where renal replacement therapy becomes necessary.