UA Diagnostics

Question 1

When would you order a UA

Answer 1

• Flank pain, back pain, abdominal pain, painful or frequent urination, changes in urine color (blood)
• Part of wellness exam, new pregnancy evaluation

Question 2

Purpose of the UA

Answer 2

Detect:

• substances secreted in the urine reflecting metabolic disturbances
• ->Ex: glucose, nitrite, ketones
• Intrinsic renal conditions
• ->Ex: acute or chronic kidney dz, other dx’s resulting in the failure of the kidney to maintain homeostasis of body fluid volume and composition

Question 3

Types of Urine Specimens

Answer 3

• Random
• Catheter
• Midstream clean-catch
• First morning
• Fasting
• 2 hour post prandial
• Suprapubic puncture
• Pediatric bags

Question 4

Three components of UA

Answer 4

1. Physical: color, transparency, odor, volume
2. Chemical: protein, glucose, ketone, bilirubin, pH, blood, nitrite, leukocyte esterase, urobilinogen, specific gravity
3. Microscopic (“formed elements”): WBC’s, RBCs, epithelial cells, casts, crystals, microorganisms

Question 5

How is a UA ordered?

Answer 5

• Dipstick UA: typical UA point of care diagnostic test
• Dipstick UA w/micro if indicated
• Complete UA (includes micro)
• Complete UA with relax urine culture: UA, micro eval, and culture

Question 6

Colored Urine Specimen and what it means

Answer 6

Straw: normal
Red: blood in the urine
Amber: Dehydrated

Question 7

Turbid Urine Specimens

Answer 7

=Cloudy samples

–>Cells, infection

Question 8

Reagent Strip/Dipstick Analysis

Answer 8

• Convenient and easy to use
• Requires strict compliance w/ directions to ensure analytical reliability
• DO NOT store in a refrigerator
• Avoid exposing reagent strips to moisture, fluorescence light, sunlight, heat, acids, alkalis,
• Do not touch test areas of reagent strip

Question 9

Leukocyte esterase

Answer 9

• WBC’s in the urine

- ->this is a marker for WBC’s

Question 10

Nitrites

Answer 10

• Most specific test on dipstick to identify infection!

- Convert nitrates to nitrites by bacteria (gram -)

Question 11

Most common cause of UTI’s

Answer 11

E. coli

Question 12

Urobilinogen

Answer 12

• RBC breakdown

- Indicative of hemolysis, bilirubin process

Question 13

Protein

Answer 13

• Reabsorption should be 100% by the kidneys, thus there should be NO protein in the urine (a.k.a Albumin)
• Filtering process in the kidney is breaking down= DM, HTN that lead to nephropathy/chronic kidney dz (CKD)

Question 14

pH

Answer 14

-Helps you assess if acidic or alkalotic

Question 15

Blood

Answer 15

• Should be no blood in the urine
• Kidney stones: nephrolithiasis
• Menstruation: contaminated sample
• Note: not actually detecting RBC’s
• ->enzymatic rxn when RBC’s are present in the urine

Question 16

Specific gravity

Answer 16

• Concentration of pt’s urine low= hydrated

- Concentration high=Dehydrated

Question 17

Ketones

Answer 17

-Metabolite of fat breakdown in the body
Causes: dietary changes, persistent N/V (body starts to breakdown fat for energy source)
-DKA!!! uncontrolled diabetes, hyperglycemia

Question 18

Bilirubin

Answer 18

-Part of physiological process of bilirubin breakdown

Question 19

Glucose

Answer 19

Approximately 250, patient starts spilling over glucose into urine (DM)

Question 20

Microscopic exam of the. urine sediment used to identify:

Answer 20

• Cells
• Casts
• Crystals

Question 21

What are the associated conditions with RBC?

Answer 21

• Acute Kidney Injury (AKI)
• Ureterolithiasis
• neoplasm
• Infection

Question 22

WBC

Answer 22

• Infection

- Renal inflammatory process: interstitial nephritis

Question 23

Renal epithelial

Answer 23

AKI: acute tubular necrosis, interstitial nephritis, nephritic syndrome

Question 24

Squamous epithelial

Answer 24

Contamination!!

Question 25

Oval fat bodies

Answer 25

Nonspecific, nephrotic syndrome

Question 26

Urinary Casts

Answer 26

- Urinary protein forms fibrils that attach to the epithelial cells lining the tubule lumen as: - ->Urine tubules become very concentrated - ->Urine flow ceases (stasis occurs) - ->Urinary pH is very low - ->Urinary salt concentration is high -Fibrils may intertwine to form cast--> Casts may entrap chemicals or formed elements that are present in the urine-->casts are eventually washed out of their point of origin and appear in. urine

Question 27

Tamm-Horsfall Glycoprotein

Answer 27

- Major protein constituent of normal urine (and often forms the common matrix of casts) - Major defense protein of urothelium against bacteria - Reagant chemical strips DO NOT detect this protein b/c so heavily glycosylated

Question 28

Common Urinary Casts

Answer 28

- Hyaline - WBC - RBC - Granular - Renal tubular epithelial cell - Waxy - Broad

Question 29

Associated condition with Hyaline casts

Answer 29

Nonspecific, may be normal

Question 30

RBC

Answer 30

AKI (glomerulonephritis), nephritic syndrome

Question 31

WBC

Answer 31

Infection (pyelonephritis), AKI/renal inflammatory process

Question 32

Epithelial

Answer 32

AKI (acute tubular necrosis interstitial nephritis), nephritic syndrome

Question 33

Granular ("muddy brown")

Answer 33

AKI. (acute tubular necrosis)

Question 34

Waxy

Answer 34

Nonspecific; chronic renal dz

Question 35

Broad

Answer 35

Chronic renal dz

Question 36

Abnormal Urinary Crystals

Answer 36

-Typically found @ acidic urinary pH | Causes: Abx, amino acids, altered metabolism (bilirubin, cholesterol)