Ch 5 Urinalysis Flashcards
Clinical reasons for performing urinalysis testing
- An important indicator of health
- A screening test for various functions
- Cost effective
- Non-invasive procedure
- Simple to perform
A screening test to detect and assess:
Renal function/disorder
Endocrine or Metabolic function/disorder
Urinary tract infection
Systemic diseases
Methods of Urine Collection
Non-instrumented
Instrumented
Non-instrumented Collection
First-morning void
Random urine specimen
Clean catch urine specimen
24-hour urine specimen
Instrumented collection
Urethral catheterization
Suprapubic Needle Aspiration
Catheterization and Bladder Irrigation
UA’s should be analyzed while:
Fresh, within 1-2 hours
If unable to test the urine specimen at time of delivery, you should:
Refrigerate the specimen within 3-6 hours
What will happen to the UA if left at room temperature?
Decompose due to bacteria and deliver inaccurate results
Produces ammonia
Urea splitting bacteria
Ammonia combined with hydrogen irons will:
Increase pH
Glucose in the urine that is used by bacteria for energy will result in:
False negative for glycosuria
Will deteriorate if left without any preservative
Urinary elements, like blood cells and casts
Most concentrated
Increase number of abnormal elements
Decreased deterioration of formed elements
Recommended specimen for chemical and microscopic examination
First morning void
Collected anytime
Most convenient and most common
Can detect abnormalities but not as sensitive as first morning void
Random UA
Specimen of choice for bacterial cultures
- Perform cultures within 12 hours after collection, only if refrigerated
- Genitalia must be cleaned with mild antiseptic solution
- Collect midstream in a sterile container
Clean catch UA
Gives quantitative results
Preservatives may be needed
24-hour UA
Not recommended for bacteriologic examination
Use only if no other way to collect urine
Commonly used on obese patients with difficulty in urine collection
Urethral Catheterization
Used in place of catheter for obtaining a single UA
Avoids vaginal and urethral contamination
Performed for bladder outlet obstruction (urinary retention)
Suprapubic Needle Aspiration
Vigorous transcatheter agitation
Yields optimum cellular sample of bladder epithelium for cytologic study
50-72 mL saline inserted into bladder
Catheterization and Bladder irrigation
Urine sample analysis:
- Physical
- Chemical
- Microscopic
Physical analysis includes:
Volume
Color
Turbidity
Odor
Specific Gravity
Normal volume in a 24-hour period ranges from:
600-2000 mL
Average 24-hour volume
1500 mL
Amount of volume of urine is directly related to:
Fluid intake
Temperature and climate
Amount of perspiration
Gives color to urine
Pigment (urochrome) concentration
Normal color
Straw (light yellow) to dark amber
Color can vary because of:
Foods or medications
Blue green
Methylene blue
Dark orange
Pyridium
Milky white
Chyle
Olive green to brown black
Phenols (poisonous compound, antimicrobial agent)
Yellow to brown (green foam when shaken)
Bile
Red or red-brown (smokey)
Blood
Turbid alkaline is due to:
Amorphous phosphate
Amorphous carbonate
Turbid Acidic urine is due to:
Amorphous urates
Pinkish turbidity frequently indicates the presence of:
Urates
Normal urine has a characteristic odor due to:
Volatile acids
Ammonia odor is due to:
breakdown of urea by bacteria
Not considered to be of special diagnostic importance
Odor
Sweet or fruity smell
Ketones
Pungent smell
Ammonia produced by bacteria
Maple syrup smell
Congenital metabolic disease
Musty or mousy smell
Infant with phenylketonuria
Specific gravity of random urine
1.003-1.035
Specific Gravity of 24-hour urine
1.015-1.025
Chemical Analysis includes:
1) Glucose
2) Ketones
3) Occult blood
4) Bilirubin
5) Urobilinogen
6) pH
7) Protein
8) Nitrite
9) Leukocyte esterase (LE)
Normal glucose
Negative
Urine glucose is dependent on
Blood glucose
Glomerular filtration
Degree of tubular reabsorption
Glucosuria will appear in urine once _____ in blood is exceeded
160-180 mg/dL
Glucose may indicate
Diabetes mellitus
Hyperglycemia condition
Normal ketones
Negative
Ketonuria is a result of:
incomplete fatty acid utilization
Ketones may indicate:
Diabetes mellitus
Increase ketone in the blood or urine
Ketosis
Ketosis is found in conditions like:
Decreased carbohydrates
Diabetes
Dietary imbalance (High fat/low carb)
Eclampsia
Prolonged vomiting
Diarrhea
Intact RBCs present in the urine may indicate:
Damage/trauma to kidney or urinary tract
Renal Diseases
- Glomerulonephritis
- Malignant HTN
- Polycystic kidney disease
Menstrual contamination or exercise
Normal bilirubin
Negative
Any condition that causes ______ will cause bilirubin in urine
Jaundice
Yellow to brown (greenish foam when shaken)
Bilirubin
Bilirubinuria indicates
Hepatocellular disease
Intra or extra-hepatic biliary obstruction
Normal Urobilinogen
<1 EU or <1 mg/dL
Any increase indicates liver disease and hemolytic disease
Urobilinogen
Range for pH
4.6 to 8.0
Average pH
6.0
Pathologic conditions that may cause acidic urine
Respiratory and metabolic acidosis
UTI (E. Coli)
Uremia
Severe diarrhea
Starvation
Pathologic conditions that cause alkaline urine:
UTIs (Proteus and Pseudomonas species)
Respiratory and metabolic alkalosis
Normal protein
Negative
Important indicator for renal disease
Protein
Two mechanisms that cause proteinuria:
Glomerular damage
Defect in the reabsorption process of the tubules
Minimal proteinuria
(<0.5 g/day)
Moderate proteinuria
0.5-3.5 g/day
Severe proteinuria
> 3.5 g/day
Polycystic kidneys
Chronic pyelonephritis
Inactive chronic glomerulonephritis
Benign orthostatic proteinuria
Minimal proteinuria
Nephrosclerosis
Tubular interstitial disease
Preeclampsia
Diabetes nephropathy
Malignant HTN
Pyelonephritis with HTN
Toxic nephropathies
Moderate Proteinuria
Glomerulonephritis
Lupus nephritis
Amyloid disease
Lipoid nephrosis
Intercapillary glomerulosclerosis
Severe venous congestion of the kidney
Severe proteinuria
Normal nitrate
Negative
Nitrite is formed by:
Breakdown of nitrates (E. coli)
Enzyme
Released by neutrophils in urine
Indirect test for bacteriuria
Leukocyte esterase (LE)
Associated with an inflammatory process in or around the urinary tract
Leukocyturia
Macroscopic analysis
Appearance
Chemical analysis
Dip stick
Microscopic analysis
Looking for Formed elements
Most UA consist of:
Macroscopic analysis
Chemical analysis
Microscopic analysis
Normal RBC Range (high power field)
0-3
Normal WBC range (high power field)
0-2
Normal epithelial cell range (HPF)
0-1
Normal bacterial range
Negative to trace
Critical values:
Strong positive for glucose and ketones
Glucose >1000 mg/dL, with small, medium, or large ketones
Urine Colony Count >50,000 colonies/mL
Normal secretion range of proteins
10-100 mg
Clinical proteinuria is defined as the loss of
> 500mg/day
Mild proteinuria may be the result of:
HTN
Lower UTI
Fever
Exercise
Moderate proteinuria may be the result of:
CHF
Chronic glomerulonephritis
Acute glomerulonephritis
Diabetic nephropathy
Pyelonephritis
Significant (Severe) Proteinuria may be the result of:
Amyloid
Chronic glomerulonephritis (severe)
Diabetic nephropathy
Lupus nephritis
Persistent pH >7.0 is associated with what kind of stones?
Calcium carbonate
Calcium phosphate
Magnesium-ammonium phosphate
Persistent pH’s below 5.5 are associated with what kind of stones?
Crystine
Uric acid
Increase in urobilinogen is usually from:
Hemolytic anemia
Cirrhosis
Viral Hepatitis
Absent in total biliary obstructions
Urobilinogen
Obstructions in the bile duct
Bilirubin (dark yellow to greenish brown)
Dipsticks for blood are dependent on the presence of:
Hemoglobin
RBCs
Myoglobin
Dipstick can detect as few as ____ RBCs (HPF)
1-2
Presence of how many RBCs is abnormal
> 3
A normal healthy person may have RBCs from:
Exercise
Persistent RBCs may indicate:
Glomerulonephritis
Kidney stones
Cancer
Infection
May lead to a false positive of RBCs and is highly suggestive of rhabdomyolysis
Myoglobin
Significant pyuria is defined by
> 3 WBCs
Indirect indicators for UTI
Leukocyte esterase and WBCs
Nitrite
Ketones and ketonuria along with glucose is suggestive of uncontrolled:
Type 1 diabetes
Microorganisms found is urine is most likely from:
Contamination
Number of epithelial cells found that is normal
1
Increased epithelial cells may indicate
Acute necrosis or inflammation (Glomerulonephritis)