 Annual physical examination – Routine

INTRODUCTION TO URINALYSIS Urinalysis

MLS is initiated because of their interest in testing urine before Physical exam
History Chemical exam
 Cavemen and Egyptians examined urine Microscopic exam – examine urinary sediments
o Color, clarity, odor, viscosity, sweetness
 Thomas Addis
o More on physical examination
o Addis count (17th Century) – method used in the
 Egyptian – hieroglyphics
quantitation of urine sediments – microscope
 Evident in Edwin Smith Surgical Papyrus
availability
 Hippocrates wrote uroscopy book
 Presence of Rbc casts, red cells – hematuria or glomerulo
o Used to study Art of uroscopy (5th Century BC)
nephritis
 Chemical testing for glucose and protein
o Presence of glucose – Ant testing or taste testing Importance
 Helps to determine patient with metabolic
 Easily obtained specimen to assess many
disorder like Diabetes Mellitus
metabolic functions with inexpensive tests
o Presence of protein
 Urinalysis definition : “the testing of urine with
 Frederik Dekker(1694) – determines that patient
procedures commonly performed in an
who has problems with kidney can have an
expeditious, reliable, safe, and cost-effective
increase protein in urine which can be
manner”
determined by boiling - ALBUMINURIA
1. URINE IS THE SPECIMEN THAT IS READILY AVAILABLE
 Charlatans/“pisse prophets” – not trained
2. INEXPENSIVE
o Thomas Bryant (1627) – revealed charlatans’ methods in
3. CAN GIVE SIGNIFICANT INFORMATION ABOUT THE
performing urinalysis in his book which inspired England
PATIENT’S DISEASE
to develop
 Reasons to perform:
 First medical licensure laws – Board Exam
o Aid disease diagnosis
 Part of a routine physical in 1827
o screen for asymptomatic diseases
o Richard Bright
o monitor disease progress and therapy effectiveness
 “Urinalysis can be a part of the routine
examination for the patient” Urine Composition
 Normal 95% water, 5% solutes  Red cell cast in urine - indication of
o Solutes – may vary due to patient’s diet, activity, kidney disorder – glomerulo nephritis or
metabolism, endocrine, body position hematuria
 Change in body position  WBC – 0-2 count per powerfield – normal
o orthostatic proteinuria  Bacteria
o Pag tumayo – transient o Wbc + bacteria in urine –
proteinuria indication of cystitis/upper tract
 Endocrine infection
o Insulin problems – receptor
Urine Volume
malfunction or damage in
pancreas • Determined by body’s state of hydration
 Inorganic o Depends on the amount of water that is excreted by the
 Organic kidney
 Solute variations: diet, activity, metabolism, endocrine, body • Influenced by fluid intake, nonrenal fluid loss, antidiuretic
position hormone (ADH) variations, excretion of large amounts of
 Major organic solute is urea (protein, amino acid breakdown in dissolved solids (e.g., glucose)
liver); also creatinine and uric acid • ↑Body Hydration = ↓ADH = ↑urine volume
o Urea – half of urine content
• ↓Body Hydration = ↑ADH = ↓urine volume
 Urea and creatinine identify a fluid as urine
• Usual daily volume = 1200-1500 mL
o Examine for levels of urea and creatine – determination
• Normal range = 600-2000 mL
of urine
 Inorganic: chloride, sodium, potassium Definitions
o Major inorganic solute is Chloride
o Diet makes establishing normal values hard • Oliguria: adults = <400 mL/day ↓urine output
 Formed elements not part of ultrafiltrate may indicate disease  Children = <0.5 ml/kg/hr
o Non pathologic formed elements – normal  Infants = <1 ml/kg/hr
o Causes: vomiting, diarrhea, perspiration, severe
crystals( amorphous crystals, females(squamous cells,
epithelial cells) burns
o Pathologic – Urinary casts • Anuria: cessation of urine flow
o Severe kidney damage, decreased renal blood
 Flow is dilute with low specific gravity; patients also exhibit
• Nocturia: increased urine excretion at night polydipsia
o Normally 2-3 times more excretion in the day • ADH – Arginine vasopressin
• Polyuria: >2.5 L/day 1. Neurogenic Diabetes Insipidus
a. Decrease ADH
Polyuria in Diabetes Mellitus vs. Diabetes Insipidus
i. Tumor in the brain that affects production of
• Diabetes mellitus - POLYURIA ADH
• Increased glucose concentration in blood ii. CENTRAL OR CRANIAL BRAIN
o Problem in insulin production or insulin utilization or 2. Nephrogenic Diabetes Insipidus
function a. Decrease function of ADH
o Type 1 i. Damage in the kidney
o Beta cells of islets of Langerhans in the pancreas – 1. There is ADH but there is a damage in
produces insulin – to uptake the production of glucose – kidney tubules that results to
utilization of glucose to ATP decrease binding of adh to its
o Insulin resistance receptor that prevents reabsorption
o Glucose is not converted into energy – glucose stays in of aquaporin
blood 3. Dipsogenic Diabetes Insipidus
 <160-10 mg/dl – glucose in urine is reabsorbed a. Faulty thirst mechanism
back in the circulation i. Damage in pituitary gland or in hypothalamus
 >180 mg/dl – renal threshold – amount of ↑Body Hydration = ↓ADH = ↑urine volume
substance that cannot be reabsorbed in the 4. Gestational Diabetis Insipidus
tubule – glucose is excreted in the urine a. Breakdown of ADH
 Increase urine output i. Placenta in uterus produces vasopressinase
o Increased volume caused by need to excrete the excess (anti-ADH)
glucose not reabsorbed from the ultrafiltrate; patients ↑Body Hydration = ↓ADH = ↑urine volume
exhibit polydypsia; urine appears dilute with a high
specific gravity
• Diabetes insipidus
o Decreased production or function of ADH causing
decreased reabsorption of water from ultrafiltrate; urine

Polydipsia

Polyuria
 Specimen Rejection

Specimen Collection • Unlabeled containers

• Non-matching labels and requisitions
• Disposable, wide-mouthed, and flat-bottom containers with
• Contaminated specimens - feces, paper
screw caps are recommended
• Contaminated containers
• Clear containers / at least 50 mL capacity
• Insufficient quantity
• Adhesive bags for pediatrics and large plastic containers for 24-
• Delayed or improper transport
hour specimens
o Ice, refrigeration
• Wear gloves when working with urine
• Labs have written policies for rejection
Specimen Labeling
Specimen Integrity
• Information on label:
 Test within 2 hours of collection
o Patient’s name, ID number, date, time
 Refrigerate if testing is delayed
• Additional information: age, location, physician
o 2 degrees to 8 degrees – to avoid bacterial metabolism
• PLACE LABEL ON CONTAINER, NOT LID
and growth
• Requisition form: Must accompany specimen
o Increased specific gravity
o Information must match label
 Most problems are caused by bacterial multiplication
o Time of receipt is stamped on requisition
 Increased: color, turbidity, pH, nitrite, bacteria, odor
o Other info: type of specimen, interfering med
 Decreased: glucose, ketones, bilirubin, urobilinogen, RBCs, WBCs,
casts

Changes in unpreserved Urine Table

ANALYTE CHANGE CAUSE

Color Modified/Darkened Oxidation or
reduction of
metabolites
Clarity Decreased Bacterial growth and
precipitation of
amorphous material
Odor Increased Multiplication of
 bacteria or bacterial Types of Specimen
breakdown of urea to
ammonia  The composition of urine depends on the patient’s metabolic
pH Increased Breakdown of urea to state and the timing and procedure used for collection
ammonia by  Patients must be instructed when special collection techniques
ureaseproducing are required
bacteria/loss of CO2
Random Specimen
Glucose Decreased Glycolysis and
bacterial utilization  Most common type received
Ketones Decreased Volatilization and  Routine screening for obvious abnormalities
bacterial metabolism  May be collected at any time
Bilirubin Decreased Exposure to
 Dietary intake and activity may alter results
light/photo oxidation
 Patients may have to collect a follow-up specimen
to biliverdin
Urobilinogen Decreased Oxidation to urobilin First Morning Specimen – 8 hr specimen
Nitrite Increased Multiplication of
nitrate-reducing  Ideal screening specimen
bacteria  More concentrated than a random specimen
Blood cells & casts Decreased Disintegration in  Patient is in a basal state
dilute alkaline urine  Use for orthostatic protein confirmation and urine pregnancy
Bacteria Increased Multiplication tests
 Patient collects immediately on arising, delivers to lab within 2
Specimen Preservation hours

 Ideal is bactericidal: inhibits urease and preserves formed Fasting Specimen

elements  Actually is second specimen voided – collected after the first
 Routine is refrigeration; this is a must for culture specimens morning specimen
o Causes precipitation of amorphous crystals  Does not contain metabolites from evening meal
o Must return to room temperature for chemical testing  Recommended for glucose monitoring
 Commercial transport tubes are available but they must be
compatible with tests 2-Hour Postprandial Specimen – glucose monitoring
  Patient voids before eating routine meal  7 a.m. second day – patient voids and adds this urine to the
 Eats meal specimen container
 Collects next specimen 2 hours after finishing meal  Principle: collection must begin and end with an empty bladder
 Monitors insulin therapy  Calculation for units per 24 hours includes the volume in
 Results can be compared with fasting urine specimen and blood milliliters of urine collected
test results
Handling of Timed Specimens
Glucose Tolerance Specimen
 Thoroughly mix specimen and measure
- Correlated with blood result in cc  Save a large enough aliquot to test, and repeat test if necessary
- Monitoring gestational diabetes  Keep specimen on ice or refrigerated during collection
 Institutional option for collection with blood glucose tolerance  Use appropriate and nontoxic preservatives
test – not frequently done  Review instructions with patient
 Specimens are collected at the same intervals as the blood
Catheterized Specimens
samples
 Used to correlate renal threshold with patient’s ability to  Sterile specimen collected from bladder with a catheter
metabolize glucose  Most common test is culture and sensitivity
24-Hour (Timed) Specimen  Culture first before performing routine urinalysis

Midstream Clean-Catch Specimen

 Required for quantitative results
 24-hour specimens are needed for measuring substances with  Alternative to catheterized specimen
diurnal variation (results differ in a.m. and p.m.) and substances  Less contaminated than routine collection
that vary with meals, activity, and body metabolism  Provide patient with mild cleansing material and container and
 Shorter timed specimens can be used for substances with instructions:
consistent levels o Wash hands
 Accurate timing is critical for accurate results o Clean genitalia with supplied cleanser
 Catecholamine, steroid, and electrolytes o Void into toilet, then into container, and finish into toilet
Timing Schedule Example  Do not touch or contaminate inside of container

 7 a.m.– patient voids and discards urine Suprapubic Aspiration

 Patient begins collecting urine  Completely free of contamination for culture and cytology
  External needle aspiration from the bladder o EPS examined for WBCs >10-20/ hpf: abnormal
 Possible pediatric specimen o Negative cultures on VB1 and VB2 and positive on EPS
 2 containers and VB3 show prostatitis
o 1- Culture and sensitivity  Pre- and post-massage test:
o 2- cytology o Specimen 1 – midstream clean-catch specimen
o Specimen 2 – post-massage specimen
Prostatitis Specimen
 Prostatitis is indicated by a quantitative culture result in the
 Collection similar to midstream clean-catch second glass that is 10 times higher than specimen 1
 3-glass collection:
Pediatric Specimens
o Container 1 – first urine passed
o Container 2 – midstream urine  Soft, clear plastic bags, with hypoallergenic tape applied to genital
 Massage prostate to obtain prostatic fluid area
o Container 3 – remaining urine and fluid  Monitor bag frequently
 Quantitative cultures on all 3 specimens, examine  Clean-catch method with sterile bag can be used
1 and 3 microscopically for WBCs  Bags with tubes to a larger container are available for timed
 Prostatic infection = higher WBC/hpf count in specimen 3 than specimens
specimen 1; bacterial count in specimen 3 is 10 times higher than
Drug Specimen Collection
specimen 1
 Specimen 2 is a control for bladder or kidney infection  Proper collection, labeling, handling must be documented
o Positive culture in specimen 2 invalidates positive culture  Chain of custody – documentation from the time of specimen
in specimen 3 (cannot differentiate urinary tract infection collection until the time of receipt of laboratory results;
from prostate infection) standardized form always accompanies specimen
 Prostate specimen variations  Specimen must withstand legal scrutiny
o Stamey-Mears 4-glass collection  Points to consider:
 Initial voided (VB1) o Photo ID of urine donor or ID by employer
 Midstream (VB2) o No unauthorized access to specimen
 Massaged prostate excretions (EPS) o No adulteration, substitution, or dilution of specimen
 Post-massage urine (VB3)  Witnessed vs. unwitnessed collection
 Cultures on all specimens o Determined by test orderer
o VB1 and VB2 positive = urinary infection o Both specimens must be handed immediately to collector
 Adulteration tests:
o Temperature taken within 4 min must be 32.5- 37.7°C
o Report temperatures outside of range immediately.
o Collect another specimen ASAP
o Inspect urine color for anything unusual
 Follow laboratory instructions for labeling, packaging, and
transport