Plasma or Serum Creatinine (Mass Concentration)

Why This Test Matters

Creatinine levels can indicate how well your kidneys are working. High levels may suggest kidney damage or disease, while low levels could indicate dehydration or muscle loss. This test is often used alongside other measures to monitor kidney health, especially in people with risk factors like diabetes or hypertension.

What to Expect Before the Test

No special preparation is needed for this test. You may have a small needle inserted into your arm or a blood sample collected from your finger. If you’re having a urine test, you’ll need to collect a sample over a 24-hour period. Drink plenty of fluids the day before if you’re doing a urine test to ensure accurate results.

What the Results Mean

Results are typically reported as a numerical value (mass concentration) in units like milligrams per deciliter (mg/dL) or milligrams per liter (mg/L). Your doctor will compare these results to your health history and other tests to determine if they’re within a normal range or if further action is needed.

Common Causes of Abnormal Results

High creatinine levels can be caused by kidney disease, dehydration, severe muscle damage, or conditions that reduce blood flow to the kidneys. Low levels may result from dehydration, muscle wasting, or certain medications. Other factors, like diet or exercise, can also influence creatinine levels.