Early detection of kidney disease saves lives. Learn about the essential blood tests, urine tests, imaging studies, and biopsy procedures used to diagnose and monitor kidney disease.
Kidney disease is often called a "silent disease" because symptoms may not appear until significant damage has occurred. Regular testing is the only way to catch kidney problems early. If you have diabetes, high blood pressure, a family history of kidney disease, or are over 60 years old, regular kidney screening is essential.
Dr. Rajesh Goel, Senior Nephrologist with 18+ years of experience, recommends at least annual kidney function screening for all at-risk patients. Early detection allows for lifestyle changes and medications that can slow or stop kidney disease progression.
| Test | Type | Purpose | Recommended Frequency |
|---|---|---|---|
| eGFR | Blood | Measures overall kidney function | Every 1-3 months |
| Serum Creatinine | Blood | Indicates how well kidneys filter waste | Every 1-3 months |
| Blood Urea | Blood | Measures urea waste product | Every 1-3 months |
| Blood Urea Nitrogen (BUN) | Blood | Measures urea nitrogen waste product | Every 1-3 months |
| Cystatin C | Blood | Alternative kidney function marker | As needed |
| Serum Uric Acid | Blood | Monitors purine metabolism and kidney excretion | Every 3-6 months |
| Sodium (Na) | Electrolyte | Fluid balance regulation | Every 1-3 months |
| Potassium (K) | Electrolyte | Heart rhythm and muscle function | Every 1-3 months |
| Chloride (Cl) | Electrolyte | Fluid and acid-base balance | Every 1-3 months |
| Bicarbonate (HCO₃) | Electrolyte | Acid-base status of blood | Every 1-3 months |
| Calcium | Mineral | Bone health and heart function | Every 3-6 months |
| Phosphorus | Mineral | Bone health, cardiovascular risk | Every 3-6 months |
| Magnesium | Mineral | Enzyme reactions, heart rhythm | Every 3-6 months |
| Alkaline Phosphatase | Mineral | Bone disease and liver function | Every 6-12 months |
| Intact PTH | Mineral | Bone-mineral disorder in CKD | Every 6-12 months |
| Vitamin D (25-OH) | Mineral | Calcium absorption and bone health | Every 6-12 months |
| CBC | Blood | Anemia assessment and monitoring | Every 1-3 months |
| Serum Iron | Blood | Iron availability for erythropoiesis | Every 3 months |
| Ferritin | Blood | Total iron stores assessment | Every 3 months |
| TIBC | Blood | Iron transport capacity | Every 3 months |
| Transferrin Saturation | Blood | Iron availability for ESA therapy | Every 3 months |
| Vitamin B12 | Blood | Red blood cell formation | If anemia present |
| Folate | Blood | Red blood cell formation | If anemia present |
| Fasting Blood Sugar | Diabetes | Blood glucose control monitoring | Every 3 months |
| Post-Prandial Blood Sugar | Diabetes | Post-meal glucose control | Every 3 months |
| HbA1c | Diabetes | Average glucose over 2-3 months | Every 3 months |
| Lipid Profile | Heart | Cardiovascular risk assessment | Every 6-12 months |
| Liver Function Test | Heart | Liver function and drug metabolism | Every 6-12 months |
| Serum Albumin | Nutrition | Nutritional status assessment | Every 1-3 months |
| Total Protein | Nutrition | Overall protein status | Every 3-6 months |
| Urine Routine | Urine | Screening for infection, blood, protein | Every 3-6 months |
| uACR | Urine | Detects early kidney damage (albumin leak) | Every 3-6 months |
| uPCR | Urine | Measures total protein in urine | Every 3-12 months |
| Urine Culture & Sensitivity | Urine | Identifies UTI organism and antibiotic sensitivity | As needed |
| Kidney Ultrasound | Imaging | Evaluates kidney structure and size | Every 6-12 months |
| CT Scan | Imaging | Detailed imaging for stones, tumors, trauma | As needed |
| Kidney MRI | Imaging | Advanced soft tissue evaluation | As needed |
| Kidney Biopsy | Tissue | Definitive diagnosis of kidney disease | Once (diagnostic) |
| Pre/Post-Dialysis Urea (Kt/V) | Dialysis | Dialysis adequacy assessment | Monthly |
| Hepatitis B Screening | Dialysis | Infection screening for dialysis | Annually |
| Hepatitis C Screening | Dialysis | Infection screening for dialysis | Annually |
| HIV Screening | Dialysis | Infection screening for dialysis | Annually |
eGFR is a calculated number that estimates how well your kidneys are filtering waste from your blood. It is the most important test for detecting and staging chronic kidney disease (CKD).
How It Works
The eGFR is calculated from your serum creatinine level, age, gender, and sometimes race. A higher eGFR means better kidney function.
Normal Range
90 mL/min/1.73 m² or higher
What Your Results Mean
Who Should Get Tested
Everyone with diabetes, high blood pressure, heart disease, or a family history of kidney disease. Adults over 60 should be screened annually.
Frequency
Annually for at-risk patients; every 3-6 months if eGFR is declining.
Creatinine is a waste product produced by your muscles during normal activity. Healthy kidneys filter creatinine out of the blood and into the urine. High levels in blood indicate the kidneys are not filtering properly.
How It Works
A simple blood test measures the amount of creatinine in your blood. Your doctor uses this value along with age, gender, and body size to calculate your eGFR.
Normal Range
Men: 0.7-1.3 mg/dL | Women: 0.6-1.1 mg/dL
What Your Results Mean
Who Should Get Tested
Patients with diabetes, hypertension, family history of kidney disease, or those on medications that may affect kidneys (NSAIDs, certain antibiotics).
Frequency
As part of routine annual check-up; more frequent if kidney disease is suspected.
BUN measures the amount of nitrogen in your blood that comes from urea, a waste product made when protein is broken down in your body. The kidneys remove urea from the blood.
How It Works
A simple blood test. BUN is often measured alongside creatinine. The BUN-to-creatinine ratio can help doctors determine the cause of kidney problems.
Normal Range
7-20 mg/dL
What Your Results Mean
Who Should Get Tested
Usually ordered as part of a comprehensive metabolic panel. Important for patients with kidney disease, heart failure, or GI bleeding.
Frequency
As directed by your doctor, typically alongside other kidney function tests.
Cystatin C is a protein produced by all cells in the body. Unlike creatinine, it is less affected by muscle mass, age, or diet, making it a more accurate marker of kidney function in certain patients.
How It Works
A blood test measures cystatin C levels. It may be used to confirm eGFR calculated from creatinine, especially when creatinine-based estimates may be inaccurate.
Normal Range
0.51-0.98 mg/L
What Your Results Mean
Who Should Get Tested
Elderly patients, very thin or muscular individuals, amputees, patients with cirrhosis, or when eGFR from creatinine seems inaccurate.
Frequency
As recommended by your nephrologist.
Uric acid is a waste product formed when the body breaks down purines (substances found in certain foods and cells). High levels can indicate reduced kidney excretion and may contribute to kidney stone formation and further kidney damage.
How It Works
A simple blood test measures uric acid levels. Elevated levels are common in CKD patients and gout.
Normal Range
Men: 3.4-7.0 mg/dL | Women: 2.4-6.0 mg/dL
What Your Results Mean
Who Should Get Tested
All CKD patients, patients with gout, recurrent kidney stones, or unexplained joint pain.
Frequency
Every 3-6 months in CKD patients; more often if elevated.
Blood urea measures the total amount of urea nitrogen in your blood. Urea is a waste product from protein metabolism that is excreted by the kidneys. It is a key marker alongside creatinine for assessing kidney function.
How It Works
A simple blood test. Urea levels rise when kidneys are unable to filter waste properly. It can also be affected by dehydration, high protein diet, and GI bleeding.
Normal Range
15-40 mg/dL (or 7-20 mg/dL for BUN)
What Your Results Mean
Who Should Get Tested
All CKD patients, patients with dehydration, GI bleeding, or on high protein diets.
Frequency
Every 1-3 months alongside creatinine and eGFR.
uACR measures the amount of albumin (a type of protein) in your urine compared to creatinine. Albumin in the urine is one of the earliest signs of kidney damage, especially in diabetes.
How It Works
A spot urine sample (first morning sample is best) is tested. You do not need to collect urine for 24 hours.
Normal Range
Less than 30 mg/g
What Your Results Mean
Who Should Get Tested
Everyone with diabetes (annually), hypertension, or suspected kidney disease. This is the most sensitive early test for diabetic kidney disease.
Frequency
Annually for diabetics; more frequently if abnormal.
A comprehensive dipstick and microscopic examination of your urine. It can detect blood, protein, white blood cells, bacteria, sugar, and other substances that may indicate kidney disease or urinary tract infection.
How It Works
A midstream clean-catch urine sample is dipped in reagent strips and examined under a microscope for cells, crystals, and casts.
Normal Range
Clear, pale yellow; no blood, no protein, no bacteria
What Your Results Mean
Who Should Get Tested
Part of every routine health check-up. Essential for anyone with symptoms of kidney disease (swelling, foamy urine, blood in urine).
Frequency
Annually as part of routine check-up; more frequently if abnormal.
uPCR measures total protein in your urine. Unlike uACR which measures only albumin, uPCR captures all types of protein loss. It is used to assess nephrotic-range proteinuria.
How It Works
A spot urine sample is analyzed. Values above 3.5 g/g suggest nephrotic syndrome.
Normal Range
Less than 150 mg/g (less than 0.15 g/g)
What Your Results Mean
Who Should Get Tested
Patients with persistent proteinuria on urinalysis, suspected nephrotic syndrome, or monitoring treatment response.
Frequency
As directed by nephrologist based on kidney disease severity.
Urine culture identifies the specific bacteria causing a urinary tract infection (UTI) and determines which antibiotics will be most effective. This is especially important in CKD patients who are prone to recurrent infections.
How It Works
A clean-catch midstream urine sample is cultured on special media. If bacteria grow, they are tested against various antibiotics to determine sensitivity.
Normal Range
No growth (negative culture)
What Your Results Mean
Who Should Get Tested
CKD patients with symptoms of UTI (burning urination, frequency, fever), recurrent UTIs, or before starting immunosuppressive therapy.
Frequency
As needed when infection is suspected; not a routine test.
A non-invasive imaging test that uses sound waves to create pictures of your kidneys. It shows the size, shape, and structure of the kidneys, and can detect stones, cysts, blockages, and tumors.
What It Shows
Preparation
May require fasting for 4-6 hours before the test.
A detailed imaging test using X-rays to create cross-sectional images of the kidneys, ureters, and bladder. CT with contrast provides detailed evaluation of kidney masses, stones, and vascular abnormalities.
What It Shows
Preparation
Fasting 4-6 hours; inform doctor if allergic to contrast or have kidney disease (contrast risk).
An advanced imaging test that uses magnetic fields and radio waves to create detailed images without radiation. It is especially useful for evaluating complex kidney masses and planning surgery.
What It Shows
Preparation
No metal objects; inform doctor of implants or claustrophobia.
Electrolyte imbalances are common and potentially dangerous in CKD. Regular monitoring helps prevent life-threatening complications like hyperkalemia and metabolic acidosis.
Normal Range
136-145 mEq/L
What Your Results Mean
Frequency
Every 1-3 months in CKD patients
Normal Range
3.5-5.0 mEq/L
What Your Results Mean
Frequency
Every 1-3 months; more often with RAAS blockers
Normal Range
98-106 mEq/L
What Your Results Mean
Frequency
Every 1-3 months in CKD patients
Normal Range
22-28 mEq/L
What Your Results Mean
Frequency
Every 1-3 months in CKD; guides bicarbonate supplementation
CKD-Mineral and Bone Disorder (CKD-MBD) is a serious complication. As kidney function declines, calcium, phosphorus, and PTH imbalances lead to bone disease and cardiovascular calcification.
Normal Range
8.5-10.5 mg/dL
What Your Results Mean
Frequency
Every 3-6 months in CKD
Normal Range
2.5-4.5 mg/dL
What Your Results Mean
Frequency
Every 3-6 months in CKD stages 3-5
Normal Range
1.7-2.2 mg/dL
What Your Results Mean
Frequency
Every 3-6 months in CKD
Normal Range
44-147 IU/L
What Your Results Mean
Frequency
Every 6-12 months in CKD
Normal Range
10-65 pg/mL (target varies by CKD stage)
What Your Results Mean
Frequency
Every 6-12 months; more frequent in advanced CKD
Normal Range
30-100 ng/mL (sufficient >30)
What Your Results Mean
Frequency
Every 6-12 months in CKD
Anemia is nearly universal in advanced CKD. These tests help diagnose the type and severity of anemia and guide treatment with erythropoietin and iron supplementation.
CBC measures haemoglobin, white blood cells, platelets, and red blood cell indices. Anemia is extremely common in CKD due to reduced erythropoietin production by damaged kidneys.
Normal Range
Haemoglobin: Men 13-17 g/dL, Women 12-15 g/dL
What Your Results Mean
Frequency
Every 1-3 months in CKD
Measures the amount of iron in your blood. Essential for evaluating anemia in CKD patients, especially before starting erythropoietin therapy.
Normal Range
60-170 mcg/dL
What Your Results Mean
Frequency
Every 3 months in CKD with anemia
Ferritin measures total iron stores in the body. In CKD, ferritin levels guide iron supplementation and erythropoietin therapy.
Normal Range
200-500 ng/mL (CKD target)
What Your Results Mean
Frequency
Every 3 months in CKD with anemia
TIBC measures the blood's capacity to bind iron with transferrin. It helps differentiate between iron deficiency anemia and anemia of chronic disease.
Normal Range
250-370 mcg/dL
What Your Results Mean
Frequency
Every 3 months with iron studies
TSAT calculates the percentage of transferrin that is saturated with iron. It is a key marker for iron-deficiency anemia in CKD and guides ESA therapy.
Normal Range
20-50%
What Your Results Mean
Frequency
Every 3 months in CKD with anemia
Vitamin B12 is essential for red blood cell formation and nerve function. Deficiency can cause or worsen anemia independent of kidney function.
Normal Range
200-900 pg/mL
What Your Results Mean
Frequency
If anemia is unexplained or macrocytosis present
Folate (Vitamin B9) works with B12 for red blood cell production. Deficiency causes megaloblastic anemia.
Normal Range
2.7-17.0 ng/mL
What Your Results Mean
Frequency
If anemia is unexplained or macrocytosis present
Diabetes is the #1 cause of kidney disease worldwide. Tight blood sugar control is essential to slow progression of diabetic kidney disease.
Measures blood glucose after an overnight fast (8-12 hours). Essential for monitoring diabetes control, which is the leading cause of kidney disease.
Normal Range
70-100 mg/dL (normal), <126 mg/dL (diabetic)
What Your Results Mean
Frequency
Every 3 months in diabetic CKD patients
Measures blood glucose 2 hours after a meal. Shows how well the body handles glucose after eating.
Normal Range
<140 mg/dL (normal), <200 mg/dL (diabetic)
What Your Results Mean
Frequency
Every 3 months in diabetic CKD patients
HbA1c reflects average blood sugar over the past 2-3 months. It is the gold standard for monitoring long-term diabetes control and guiding treatment in diabetic kidney disease.
Normal Range
<5.7% (normal), <7% (diabetic target)
What Your Results Mean
Frequency
Every 3 months in diabetic CKD patients
CKD patients have 10-20x higher cardiovascular risk than the general population. Heart disease is the leading cause of death in CKD patients.
Measures cholesterol and triglycerides. CKD patients have significantly elevated cardiovascular risk, and lipid management is crucial.
Normal Range
Total Cholesterol <200, LDL <100, HDL >40, Triglycerides <150 mg/dL
What Your Results Mean
Frequency
Every 6-12 months in CKD
LFT measures liver enzymes (SGOT, SGPT, ALP) and bilirubin. Important for drug metabolism and detecting liver disease that may coexist with kidney disease.
Normal Range
SGOT: 5-40 U/L, SGPT: 7-56 U/L, ALP: 44-147 IU/L
What Your Results Mean
Frequency
Every 6-12 months in CKD
Malnutrition is common in CKD, especially in advanced stages. Protein-energy wasting is associated with poor outcomes and hospitalization.
Albumin is the main protein in blood, made by the liver. Low albumin in CKD indicates malnutrition, inflammation, or nephrotic syndrome. It is a strong predictor of outcomes.
Normal Range
3.5-5.0 g/dL
What Your Results Mean
Frequency
Every 1-3 months in CKD stages 4-5
Total protein measures all proteins in your blood (albumin + globulin). It helps assess nutritional status and detect conditions like nephrotic syndrome or multiple myeloma.
Normal Range
6.0-8.3 g/dL
What Your Results Mean
Frequency
Every 3-6 months in CKD
Patients on dialysis require regular monitoring of dialysis adequacy and screening for blood-borne infections as part of standard dialysis protocol.
Measures urea before and after dialysis to calculate Kt/V (dialysis adequacy) and URR (Urea Reduction Ratio). Ensures dialysis sessions are effective.
Normal Range
Kt/V >1.2, URR >65%
What Your Results Mean
Frequency
Monthly for hemodialysis patients
Hepatitis B (HbsAg, Anti-HBs) screening is mandatory for dialysis patients to prevent transmission and guide vaccination.
Normal Range
HbsAg negative, Anti-HBs positive (if vaccinated)
What Your Results Mean
Frequency
At initiation of dialysis, then annually
Anti-HCV testing identifies hepatitis C infection. Dialysis patients are at higher risk due to blood exposure.
Normal Range
Anti-HCV negative
What Your Results Mean
Frequency
At initiation of dialysis, then annually
HIV testing is part of standard dialysis protocol to ensure safety of staff and patients.
Normal Range
HIV 1&2 negative
What Your Results Mean
Frequency
At initiation of dialysis, then annually
A kidney biopsy is the gold standard for diagnosing many kidney diseases. A small piece of kidney tissue is removed using a thin needle and examined under a microscope.
The Procedure
Performed under local anesthesia with ultrasound guidance. You lie face down (or on your side). A needle is inserted through the back to obtain tiny tissue samples. The procedure takes about 30-60 minutes.
Results
Tissue is examined by a kidney pathologist. Results typically take 3-7 days and can diagnose: glomerulonephritis, IgA nephropathy, diabetic nephropathy, lupus nephritis, FSGS, amyloidosis, and many other conditions.
| Test | Type | Purpose | Frequency |
|---|---|---|---|
| eGFR | Blood | Measures overall kidney function | Every 1-3 months |
| Serum Creatinine | Blood | Indicates how well kidneys filter waste | Every 1-3 months |
| Blood Urea | Blood | Measures urea waste product | Every 1-3 months |
| Blood Urea Nitrogen (BUN) | Blood | Measures urea nitrogen waste product | Every 1-3 months |
| Cystatin C | Blood | Alternative kidney function marker | As needed |
| Serum Uric Acid | Blood | Monitors purine metabolism and kidney excretion | Every 3-6 months |
| Sodium (Na) | Electrolyte | Fluid balance regulation | Every 1-3 months |
| Potassium (K) | Electrolyte | Heart rhythm and muscle function | Every 1-3 months |
| Chloride (Cl) | Electrolyte | Fluid and acid-base balance | Every 1-3 months |
| Bicarbonate (HCO₃) | Electrolyte | Acid-base status of blood | Every 1-3 months |
| Calcium | Mineral | Bone health and heart function | Every 3-6 months |
| Phosphorus | Mineral | Bone health, cardiovascular risk | Every 3-6 months |
| Magnesium | Mineral | Enzyme reactions, heart rhythm | Every 3-6 months |
| Alkaline Phosphatase | Mineral | Bone disease and liver function | Every 6-12 months |
| Intact PTH | Mineral | Bone-mineral disorder in CKD | Every 6-12 months |
| Vitamin D (25-OH) | Mineral | Calcium absorption and bone health | Every 6-12 months |
| CBC | Blood | Anemia assessment and monitoring | Every 1-3 months |
| Serum Iron | Blood | Iron availability for erythropoiesis | Every 3 months |
| Ferritin | Blood | Total iron stores assessment | Every 3 months |
| TIBC | Blood | Iron transport capacity | Every 3 months |
| Transferrin Saturation | Blood | Iron availability for ESA therapy | Every 3 months |
| Vitamin B12 | Blood | Red blood cell formation | If anemia present |
| Folate | Blood | Red blood cell formation | If anemia present |
| Fasting Blood Sugar | Diabetes | Blood glucose control monitoring | Every 3 months |
| Post-Prandial Blood Sugar | Diabetes | Post-meal glucose control | Every 3 months |
| HbA1c | Diabetes | Average glucose over 2-3 months | Every 3 months |
| Lipid Profile | Heart | Cardiovascular risk assessment | Every 6-12 months |
| Liver Function Test | Heart | Liver function and drug metabolism | Every 6-12 months |
| Serum Albumin | Nutrition | Nutritional status assessment | Every 1-3 months |
| Total Protein | Nutrition | Overall protein status | Every 3-6 months |
| Urine Routine | Urine | Screening for infection, blood, protein | Every 3-6 months |
| uACR | Urine | Detects early kidney damage (albumin leak) | Every 3-6 months |
| uPCR | Urine | Measures total protein in urine | Every 3-12 months |
| Urine Culture & Sensitivity | Urine | Identifies UTI organism and antibiotic sensitivity | As needed |
| Kidney Ultrasound | Imaging | Evaluates kidney structure and size | Every 6-12 months |
| CT Scan | Imaging | Detailed imaging for stones, tumors, trauma | As needed |
| Kidney MRI | Imaging | Advanced soft tissue evaluation | As needed |
| Kidney Biopsy | Tissue | Definitive diagnosis of kidney disease | Once (diagnostic) |
| Pre/Post-Dialysis Urea (Kt/V) | Dialysis | Dialysis adequacy assessment | Monthly |
| Hepatitis B Screening | Dialysis | Infection screening for dialysis | Annually |
| Hepatitis C Screening | Dialysis | Infection screening for dialysis | Annually |
| HIV Screening | Dialysis | Infection screening for dialysis | Annually |
Don't wait for symptoms. Early detection of kidney disease can prevent progression to kidney failure. Consult Dr. Rajesh Goel for comprehensive kidney evaluation.
These tests are used to diagnose and monitor the following kidney conditions:
Medically reviewed by Dr Rajesh Goel, Senior Nephrologist, New Delhi
Last reviewed: January 2025 | Last updated: 30 July 2026
