Creatinine is a waste product produced by muscles and eliminated by the kidneys. The creatinine level in the blood is an important indicator of kidney function. When the kidneys are not functioning properly, the creatinine level rises, indicating kidney failure. One common question among patients with this condition is what creatinine level warrants the start of dialysis. This article explores the various aspects related to creatinine and the decision to begin dialysis.
Understanding Creatinine and Its Role
What is Creatinine?
Creatinine is a breakdown product of creatine, a molecule used by muscles to produce energy. It is filtered by the kidneys and excreted in the urine.
Measuring Creatinine Levels
Creatinine levels are measured through a simple blood test. Normal creatinine levels vary based on age, sex, muscle mass, and overall health. Generally, normal levels range between 0.6 and 1.2 mg/dL in men and between 0.5 and 1.1 mg/dL in women.
Kidney Failure and Creatinine Levels
Acute (AKI) and Chronic Kidney Disease (CKD)
There are two main types of kidney failure: acute kidney injury (AKI), which occurs rapidly, and chronic kidney disease (CKD), which develops slowly over several years. In both cases, a high creatinine level indicates decreased kidney function.
Stages of Kidney Disease
Chronic kidney disease is classified into five stages, determined by the glomerular filtration rate (GFR), which assesses the kidneys’ ability to filter blood.
- Stage 1: Normal kidney function (GFR ≥ 90 mL/min/1.73 m²) with evidence of kidney disease.
- Stage 2: Mildly decreased kidney function (GFR = 60-89 mL/min/1.73 m²).
- Stage 3: Moderately decreased kidney function (GFR = 30-59 mL/min/1.73 m²).
- Stage 4: Severely decreased kidney function (GFR = 15-29 mL/min/1.73 m²).
- Stage 5: Kidney failure (GFR < 15 mL/min/1.73 m²), often requiring dialysis.
When to Start Dialysis?
Role of Creatinine Level
The creatinine level alone does not determine the need to start dialysis. Other factors, such as symptoms, quality of life, and glomerular filtration rate (GFR), are also considered.
Indications for Dialysis
Clinical guidelines generally recommend starting dialysis when:
- The GFR is below 15 mL/min/1.73 m².
- The patient has severe symptoms of uremia (buildup of waste in the blood) such as nausea, vomiting, extreme fatigue, and cognitive impairment.
- There are signs of severe hyperkalemia (high potassium levels), uncontrolled metabolic acidosis, or fluid overload that cannot be managed with medications.
Specific Creatinine Values
Although there is no universal threshold, a creatinine level above 8-10 mg/dL in non-diabetic patients and above 6-8 mg/dL in diabetic patients often signals the need to consider dialysis, depending on symptoms and GFR.
Other Considerations Before Starting Dialysis
Comprehensive Health Evaluation
Doctors consider the patient’s overall health, including the presence of cardiovascular disease, infections, and other complications.
Patient Preferences
The patient’s preferences and quality of life are crucial factors in the decision to start dialysis. Some patients may choose to delay dialysis for various personal reasons.
Alternative Methods
Before starting dialysis, doctors may try to optimize medical and dietary treatments to manage symptoms and slow the progression of kidney failure.
Conclusion
The decision to start dialysis (commencer le dialyse) is not based solely on a specific creatinine level but on a comprehensive assessment of kidney function, symptoms, quality of life, and patient preferences. Creatinine level is an important indicator but must be considered in conjunction with other clinical factors. Open communication between the patient and the medical team is essential to determine the appropriate time to begin dialysis.
