Ccr

Creatinine Clearance
Synonyms	N/A
Pronounce	N/A
Specialty	N/A
Symptoms
Complications	Chronic kidney disease, Acute kidney injury
Onset
Duration
Types	N/A
Causes
Risks
Diagnosis	Blood test, Urine test
Differential diagnosis	N/A
Prevention	N/A
Treatment
Medication
Prognosis
Frequency
Deaths	N/A

Creatinine Clearance (Ccr) is a measure used to assess the glomerular filtration rate (GFR) of the kidneys. It is an important indicator of renal function and is used to detect and monitor kidney disease.

Physiology

Creatinine is a waste product formed by the normal breakdown of muscle tissue. It is produced at a relatively constant rate and is excreted by the kidneys. The clearance of creatinine from the blood is used as an estimate of the GFR, which is the rate at which the kidneys filter blood.

Measurement

Creatinine clearance can be measured using a 24-hour urine collection and a blood test to determine the concentration of creatinine in both urine and blood. The formula for calculating creatinine clearance is:

Ccr = (Ucr × V) / Pcr

where:

• Ccr = Creatinine clearance (mL/min)
• Ucr = Urine creatinine concentration (mg/dL)
• V = Urine flow rate (mL/min)
• Pcr = Plasma creatinine concentration (mg/dL)

Clinical Significance

Creatinine clearance is used to assess kidney function. A decreased creatinine clearance indicates impaired kidney function, which can be due to acute kidney injury or chronic kidney disease. It is also used to adjust the dosage of medications that are excreted by the kidneys.

Normal Values

Normal creatinine clearance values vary based on age, sex, and body size. Generally, normal values are:

• Men: 97 to 137 mL/min
• Women: 88 to 128 mL/min

Factors Affecting Creatinine Clearance

Several factors can affect creatinine clearance, including:

• Age: Creatinine clearance decreases with age.
• Muscle mass: Individuals with higher muscle mass may have higher creatinine levels.
• Diet: High protein intake can increase creatinine production.
• Medications: Certain medications can affect creatinine levels.

Limitations

While creatinine clearance is a useful measure of kidney function, it has limitations. It can be affected by factors such as muscle mass and diet, and it may not accurately reflect GFR in certain populations, such as those with muscle wasting or obesity.

Alternatives

Other methods to estimate GFR include:

• Estimated Glomerular Filtration Rate (eGFR) using equations such as the MDRD or CKD-EPI.
• Inulin clearance test, which is more accurate but less commonly used.

See Also

• Glomerular filtration rate
• Chronic kidney disease
• Acute kidney injury
• Renal function

External Links

• [Link to relevant medical resources]

Classification
External resources