Serum Creatinine (S. creatinine)
Serum Creatinine (S. creatinine) is a commonly used marker to evaluate kidney function. It is a waste product generated from the breakdown of creatine, a molecule found in muscles. Creatinine is filtered from the blood by the kidneys and excreted into the urine. The level of serum creatinine is used to assess kidney function for several reasons:
- Indicator of Glomerular Filtration Rate (GFR): Glomerular filtration rate (GFR) is a measure of how well the kidneys are filtering waste products from the blood. Creatinine is filtered from the blood by the kidneys, so the level of serum creatinine is inversely related to the GFR. Higher levels of serum creatinine indicate lower GFR and impaired kidney function, while lower levels indicate higher GFR and better kidney function.
- Screening for Kidney Disease: Elevated serum creatinine levels can indicate acute or chronic kidney disease. Acute kidney injury (AKI) or chronic kidney disease (CKD) can cause impaired kidney function, leading to decreased creatinine clearance and elevated serum creatinine levels.
- Monitoring Kidney Function: Serum creatinine levels are monitored over time to assess changes in kidney function. This is particularly important for individuals with known kidney disease, diabetes, hypertension, or other conditions that can affect kidney function.
- Adjusting Medications: Some medications are cleared from the body by the kidneys. Elevated serum creatinine levels may indicate reduced kidney function, which can affect the dosing of medications that are renally cleared. Monitoring serum creatinine levels helps healthcare providers adjust medication dosages to prevent toxicity or adverse effects.
- Assessment of Acute Kidney Injury: Significant increases in serum creatinine levels over a short period may indicate acute kidney injury, which can occur due to various reasons such as dehydration, sepsis, or nephrotoxic medications.
- Risk Stratification: Serum creatinine levels, along with other factors such as age, gender, and comorbidities, are used to stratify patients into different risk categories for kidney disease and related complications.