Chronic kidney failure

Disease Description (Causes and Symptoms)

• Definition: Chronic kidney disease (CKD) is a condition in which the estimated glomerular filtration rate (eGFR) remains below 60 mL/min/1.73 m² for 3 months or longer, or tests indicating kidney damage (such as proteinuria, hematuria, imaging or histological changes) remain abnormal for 3 months or longer. As it progresses, it may lead to end-stage kidney disease (requiring kidney replacement therapy).
• Main causes
  • Adults: Diabetes mellitus (most common), hypertension, glomerulonephritis, polycystic kidney disease, etc.
  • Children: Congenital abnormalities (renal hypoplasia, urinary tract obstruction, etc.), hereditary kidney diseases (e.g., Alport syndrome)
• Pathophysiology: As kidney function (glomerular filtration and tubular function) declines, regulation of body fluids, electrolytes, acid-base balance, and excretory waste products, as well as endocrine functions (erythropoietin production, vitamin D activation, etc.), deteriorates. This causes systemic complications.
• Main symptoms
  • In the early stages, no symptoms or nonspecific symptoms such as fatigue, loss of appetite, and sleep disturbances
  • As it progresses: Edema (fluid retention), hypertension, pruritus, nausea and vomiting, shortness of breath (pulmonary edema), fatigue caused by anemia, neurological symptoms (numbness, muscle weakness, coma), electrolyte abnormalities (hyperkalemia), etc.

Treatment Methods and Precautions

• Diagnosis and monitoring
  • Essential tests: Serum creatinine (for eGFR calculation), urine albumin/creatinine ratio (UACR), electrolytes, hemoglobin, calcium, phosphate, PTH, urinalysis, and renal ultrasound
  • Kidney biopsy when necessary (e.g., atypical or rapidly progressive cases)
• Treatment of the underlying cause
  • Diabetic nephropathy: Strict blood glucose control (SGLT2 inhibitors are often recommended when applicable)
  • Hypertension: Blood pressure control (generally ACE inhibitors or ARBs are preferred, but combined use is prohibited)
  • Specific treatment for underlying diseases such as glomerulonephritis
• Delaying the progression of kidney dysfunction
  • Blood pressure targets should be individualized (more stringent control is generally recommended in cases of proteinuria; consult the treating physician)
  • ACE inhibitors/ARBs are effective in slowing progression in patients with proteinuria
  • SGLT2 inhibitors: Renal function-preserving effects have been reported not only in diabetic CKD but also in some cases of proteinuric nondiabetic CKD (indications must be confirmed)
  • Lifestyle management: Low-sodium intake (adjust to approximately 2 g of sodium ~ 5 g of salt per day), appropriate protein intake (adjust according to the level of kidney function), and caution with potassium intake (restrict it when there is a risk of hyperkalemia)
• Treatment of complications
  • Anemia: Iron supplementation and, when necessary, erythropoietin or other ESAs (consult the treating physician regarding indications and target Hb)
  • Bone and mineral metabolism disorder: Phosphate binders, active vitamin D preparations, etc.
  • Metabolic acidosis: Bicarbonate supplementation (when necessary)
  • Hyperkalemia: Dietary adjustment, medication (potassium excretion agents), and emergency treatment
• Kidney replacement therapy (end-stage kidney disease)
  • Dialysis (hemodialysis or peritoneal dialysis) or kidney transplantation. Indications for initiation include uremia not controlled with treatment (loss of appetite, vomiting, coma), uncontrolled edema, hyperkalemia, metabolic acidosis, etc.
• Precautions
  • Caution with unproven treatments (herbal medicines and folk remedies), nonsteroidal anti-inflammatory drugs (NSAIDs), contrast agents, and other nephrotoxic drugs
  • Vaccination is recommended because the risks of infection and cardiovascular disease are high (including influenza, pneumococcal disease, and hepatitis B vaccines)
  • Medication doses must be adjusted according to eGFR

Checklist Before an Outpatient Visit (Documents to Bring and Preparation)

• What to bring

  • A list of all medications, supplements, and herbal medicines currently being taken (including doses and dosing times)
  • Recent test results (blood tests [creatinine, electrolytes, hemoglobin], urinalysis, urine albumin/creatinine ratio, etc.) or test result files
  • Weekly records of blood pressure, weight, and edema status; changes in urine volume; and urinary symptoms
  • Eating habits (especially sodium, protein, and potassium intake), and whether you drink alcohol or smoke

• Changes to tell the doctor about in advance during the outpatient visit

  • Sudden weight gain (worsening edema), shortness of breath or difficulty breathing, worsening vomiting or loss of appetite, muscle weakness or numbness, recently started medications (e.g., NSAIDs or antibiotics), high-potassium meals, etc.

• Example questions for the patient to prepare

  • Are any of the medications I am currently taking harmful to my kidneys?
  • Based on my recent results (creatinine and UACR), what is the condition of my kidneys?

Examples of General Questions to Ask the Doctor

• What are the main side effects and precautions of this medication (or the medication I was prescribed)?
• How can my prognosis (likelihood of progression) be predicted based on my eGFR and urine albumin level?
• What points regarding lifestyle habits (diet, exercise, and fluid intake) must I follow?
• Which tests (frequency and items) should I have, and how often?

Examples of Disease-Specific Questions

• In my case (based on my current eGFR and albumin level), when should I begin preparing for kidney replacement therapy (dialysis or transplantation)?
• Are the medications I am taking (e.g., ACE inhibitors/ARBs and SGLT2 inhibitors) the most appropriate for my kidney function, and are there any medications that I should stop or have the dose adjusted?