Investigations

Types of tests and investigations:
1. Urine Test
2. Blood Test
3. Ultrasound
4. Angiography

What can a Urine Test reveal?
 Urine is normally sterile
 Blood cells in urineàmay be a sign of different diseases in the kidneys, the

urinary system or the bladder.
 Glucose in urine à may be a sign of diabetes
 Protein in urineà may be a sign of a kidney disease and can be used to detect the early signs of kidney damage from long-standing diabetes.

Types of urine collection
 24-hour urine collection
 Clean catch urine specimen
 Important! Stop some of the medication before urine tests as drugs may affect the results of test.

24-hour urine collection
 Collect urine for 24 hours.
 Normal resultsà800 to 2000 milliliters per day (with a normal fluid intake of about 2 liters per day)
 Abnormal results:
 Reduced urination à dehydration, inadequate fluid intake, or renal insufficiency or failure.
 Increased urination à Diabetes, end-stage renal disease, high fluid intake, kidney failure

Clean Catch Urine Culture
 About 1 - 2 ounces of urine is needed for a test.
 Remove the container from the urine stream without stopping the flow. Individual may finish urinating into the toilet bowl.
 Sample is sent to the lab.
 Clean Catch Urine Specimen can be used for urine specific gravity.

Urine Specific Gravity
 Requires clean catch urine specimen
 Used to evaluate body's water balance and urine concentration
 Normal values are between 1.002 to 1.028.

Urine pH
 Clean Catch Urine Specimen
 Measure the acidity of urine
 Normal Range: 4.6-8.0
 High pH à Kidney Failure, UTI
 Low pH à emphysema

RBC in Urine
 Clean catch urine specimen
 Normal values are 4 RBC per high power field (RBC/HPF) or fewer. Normal value ranges may vary slightly among different laboratories.
 Greater than normal value: cystitis, pyelonephritis, kidney tumor, kidney stones, glomerulonephritis.

Blood Test
 Blood sample can be analyzed for creatinine, estimated glomerular filtration rate and blood urea nitrogen (BUN)
 The level of these waste products in the blood increases as kidney filtration declines.

Creatinine
 The breakdown product of creatine, which is an important part of muscle.
 The normal value is 0.8 to 1.4 mg/dL.
 Females usually have lower creatinine than males, because they usually have less muscle mass.

Higher than normal results:
 Glomerulonephritis
 Kidney failure
 Pyelonephritis
 Reduced kidney blood flow (shock, congestive heart failure)
 Urinary tract obstruction

Glomerular Filtration Rate
 Used to check how well the kidneys are working
 A formula is used to get the results, where age, gender, height, weight and race are taken into account
 According to the National Kidney Foundation(US), the normal results range from 90 - 120 mL/min.
 Older people will have lower normal GFR levels, because GFR decreases with age.
 Normal value ranges can vary slightly among different laboratories.

Blood Urea Nitrogen (BUN)
 Also to check kidney function
 Normal result: 7 - 20 mg/dl.
 Abnormal results (higher)à hypovolemia, kidney failure, glomerulonephritis, pyelonephritis, acute tubular necrosis, UT obstruction

Angiography
• X-ray examination that shows blood flow in the arteries and veins.
• Needle inserted into artery
• Femoral artery usually used
• Needle is in place, long thin guide wire guided into blood vessle that needs to be examined (using fluorescent screen)
• Catheter is slipped over it pushed along until tip is in the right position
• Guide wire removed and dye injected
• Image viewed on screen / rapid sequence of X-ray pictures for further investigation (flouroscopy)


References:
http://www.netdoctor.co.uk/health_advice/examinations/urinesample.htm
http://www.nlm.nih.gov/medlineplus/ency/article/003425.htm
http://www.nlm.nih.gov/medlineplus/ency/article/007305.htm
http://www.nlm.nih.gov/medlineplus/ency/article/003777.htm