Understanding Your Lab Values and CKD Health Numbers
- Living with chronic kidney disease (CKD) can feel like learning a new language due to its complexity and progression. Initially, only a few tests might be necessary, but as CKD worsens, your kidneys struggle more with their functions, requiring more frequent and varied testing. This includes monitoring for related health conditions.
- Regular visits with healthcare professionals and completing recommended lab work are crucial for staying informed about your health. This guide provides a quick overview of the key health indicators you may find in your medical records, particularly important for CKD patients. These tests may involve blood or urine samples sent to a lab or measurements taken during exams, such as weight or blood pressure.
- Always consult your healthcare professional if you have questions about your results before taking any action.
Labs Measuring Your Kidney Health
- Serum (Blood) Creatinine
- Waste product from protein digestion and muscle breakdown.
- Removed by kidneys; high levels indicate potential kidney disease.
- Normal levels vary by age, sex, and body size.
- Cystatin C
- Protein produced by body cells, also removed by kidneys.
- Alternative or additional measure to creatinine for kidney health.
- Less common and more expensive test.
- Estimated Glomerular Filtration Rate (eGFR)
- Estimates how well kidneys remove waste from the blood.
- Calculated using creatinine, age, and sex; or cystatin C.
- Key for determining CKD stage; eGFR below 60 indicates kidney issues, below 15 indicates kidney failure.
- Measured Glomerular Filtration Rate (mGFR)
- Direct measure of kidney function.
- More accurate but complex and lengthy process.
- Used in specific situations needing precise kidney function measurement.
- Blood Urea Nitrogen (BUN)
- Waste product from protein breakdown.
- Evaluated alongside creatinine and eGFR for kidney health.
- Normal levels vary with age.
- Urine Albumin-Creatinine Ratio (uACR)
- Measures albumin and creatinine in urine.
- Indicates how well kidneys filter albumin.
- Normal level is less than 30 mg/g; higher levels can signal albuminuria.
- Urine Protein-Creatinine Ratio (uPCR)
- Measures all proteins in urine, not just albumin.
- Used for specific kidney diseases or pediatric testing.
- Normal level is less than 150 mg/g; higher levels can signal proteinuria.
Measuring Your Balance of Important Minerals and Acidity
- Potassium
- Essential mineral for heart and muscle function.
- Kidneys regulate blood potassium levels.
- Goal level: 3.5 to 5.
- Sodium
- Balances body fluid, supports nerve and muscle function.
- Kidneys help regulate fluid and sodium levels.
- Excessive sodium can lead to high blood pressure and edema.
- Limit intake to less than 2300 mg/day.
- Serum (Blood) Bicarbonate/Carbon Dioxide (CO2)
- Maintains blood acidity balance.
- Low levels can indicate metabolic acidosis.
- Goal bicarbonate/CO2 level: above 22 mEq/L.
You can always visit Understanding Your Lab Values or Blood and Urine Tests to learn even more.