Urinalysis Flashcards
what is a specimen collection
how to do it
midstream urine collection = “clean catch” after proper sanitization of the area
- may need to cath. for collection (infants/those who cannot control urination)
- specimen bags can be used for infants/children not pottytrained BUT if UTI suspected : need to cath for proper collection
Components of the urinalysis
visual appearance
- yellow: normal color from the urochrome generated from hemoglobin breakdown
- food, drugs, metabolic products and infection can all alter the appearance of the urine color
Reasons for alteration in Urine Coloration
Brown/black:
- bile, melanin, myoglobin, stool from fistula or copper poision
- fava beans, aloe, nitrofurantonin, metronidazole
Cloudy/White
- infection, chyle, lipids, propofol
Foamy
- protein, dehydration
Green/blue
- biliverdine, psudo. UTI, propofol, amitriptyline
Orange
- bile, carrots, phenaopyridine, rifampin
Purple
- bacterial overgrowth from catheter
Red
- hematuria, hemoglobin, myoglobina, beets
- odor
- urine “dipstick” analysis
- microscopy (if available)
what are some things the Urin dip stick is analyzing
- leukocytes
- nitries
- urobilinogen
- protein
- pH
- blood
- specific gravity
- ketone
- bilirubin
- glucose
what does a finding of bilirubin indicate?
false postives?
false negatives?
Bilirubin: think bile
- biliary obstruction
- hepatic disease
false postives
- chlorpromazine
- phenazopyridine
false negative
- prolonged light epsoure
- vit C
what does a finding of urobilinogen indicate?
FP? FN?
- intravascular hemolysis
- hepatic disease
FP
- phenazopyridine
- suflonamides
FN
- improper storage
Finding leukoycyte esterase indicates what ? what about nitrites?
FP?FN?
Leukocyte Esterases
- inflammatory process
- STI
- UTI
False postives
- contamination
False Negatives
- antibiotics
- glucose
- protein
- vit C
- high spec grav
Nitrites
- UTI (bacterial byproduct)
False positive
- contamination
- phenazopyridine
false negative
- bacteria which do not reduce nitries
- vit C
- high spec grav.
reasons for urine protein
- fever
- glomerular disorder
- tubular disorder
- UTI
- malignant HTN
- dehydration /exercise
- ANT
- hemogloinuria/myglobinuria
- MM
FP
- phenoazopyridine
- ammonium
- concentrate or alkaline urine
FN
- non-albumin proteinurina
- diluted urine
reasons for high spec grav?
reasons for low spec grav?
High = > 1.020 (meaning more solutes in urine = concentrated)
- dehydration
- glucosuria
- SIADH
- antidiuretic hromone use
normal spec grav = 1.004-1.019
Low = < 1.003 (dilute urine)
- adrenal insufficiency
- aldosteronism
- DI
- impaired renal function
- water intoxication
reasons for high glucose on a urinalysis
- diabetes
- fanconi syndrome
- pregnancy
fals postives
- levodopa
- phenoazopyridine
False negatives
- high pH
- high urine spec grav.
- uric acid
- vit C
reasons for ketones in the urinalysis
- DM
- ketogenic diet
- pregnancy
- starvation
- dehydration
false postives
- low pH
- high spec. grav.
False neg.
- some ketons dont show on dip
Reasons for blood in the urinalysis
- glomerular disorders
- hypercalemia
- kidney stones
- trama
- UTI
- tumor (bladder cancer)
- tubular disorder
- BPH
- cystitis/pyleoneph
- TB
False Postives
- exercsie
- hemogloinuria
- menses
- myoglobinuria
False Negatives
- high spec. grave.
- vit C
reasons for an elevated (alkaline) pH urine?
acidic?
Alkaline
- type 1 renal acidosis
- heavy antacid use
- carbonic anhydrase inhibitors
- potassium/sodium citrate
Acidic
- uric acid stones
- calcium oxilate stones
- acidemia
urine and blood pH should alwasy been the same: excpet in a renal tubular acidosis
what is microhematuria
definition
conditions you want to consider
when to consider cystoscopy
microhematuria = blood not visable by gross observation
defined as
- > 3 cells/hpf adults
- > 5 cells/hpf children
Conditions
- think genitourinary malignancies
- need to work up with cystscopy and imaging
Cystscopy?
- in low risk adults (where unsure)
- benign causes: menses, exercsie, UTI
Red Blood Cells in urine
Normal Red Blood Cells
- small, round and colorless on a UA
- “ghost cells”
Acanthocytes
- blebs, bludding or spikey lookng cells “mickey mouse”
- indicate glomerular bleeding
White Blood Cells in Urine
Indicaited abnormal if >5 wb/hpf
- neutrophils most commonly
- larger than RBC with nuclei
- indicates infection/inflammation in the body via
- UTI, STI or urilithiasis
- morning sample best to get NAAT for STI
Eosinophils = indicate interstital nephritis
