Introduction to Urinalysis

Clinical Pathology,

K. Canga, RVT

Urinary System

Designed to maintain a balance between fluid, ___________________, and acid-base _____________________by selectively eliminating _______________________from the body.

Urine is formed through __________________ filtration, tubular ___________________________, and ______________________secretion (remember everything you were taught in A&P).

Urogenital System

Medical Terminology

Pollakiuria _________________________________________

Polyuria _________________________________________

Oliguria _________________________________________

Anuria _________________________________________

Dysuria _________________________________________

Urinalysis

Urine collection can be accomplished through __________________/__________________, __________________, __________________, and __________________.

Advantages to Urinalysis

_____________________________ _____________________________ _____________________________ Provides useful information (urinary tract

and/or other body systems)

Voided Urine Sample

Easiest to obtain May be

____________________ from distal genital tract

Not satisfactory if examining for ____________________.

Voided Urine Sample Collection Use a clean container Wash prepuce or vulva (when possible) Try to collect ___________________ urine

Disadvantages to Voided Sample _____________________________ _____________________________ May be difficult in easily scared dogs and

short breeds. Why?

Expressing the Bladder

Use ____________, ____________ pressure Will feel like a balloon or ball under your hands. Make sure you are expressing in a squeezing

motion so that you are forcing urine _______________ down the urethra.

Wash external genitalia Contamination from lower urinary tract/genital

tract is a concern. Do not do manual expression if there is the

possibility of an __________________________________!!!

Urinary Catheterization

Act of placing a _______________ through ________________ into _____________.

Advantages: Less possibility of ________________________ from

lower genital tract. Helpful in ______________animals when

___________________ is difficult to palpate Disadvantages

Trauma to sensitive ____________ mucosa Possible ________________________

Catheterization

Cystocentesis

Act of obtaining a urine sample via a ______________ and ____________ directly from the ________________.

Advantages ________________ sample

Disadvantages Difficult to obtain in __________________animals Trauma to _________________ if not done

correctly

Urine Sample Preservation

Analyze all urine within _____ minutes if possible

May refrigerate for ______ hours if needed Bring to room temperature before

analysis Morning samples are more

_______________ If allowed to stand at room

temperature, may get false results.

Physical Characteristics of Urine _________________ _________________ _________________ _________________ _________________

Urine Color Normal color is due to pigments called

_________________________ Normal: light yellow to amber color Abnormals:

Red: _________ (____________) Reddish-brown: _____________or ____________ Dark yellow-brown: ____________

(_______________) Orange-Reddish brown: Normal in _____________

Urine Clarity

____________ vs. _____________ Cloudy could indicate increase _________,

____________, __________, ____________and _____________.

______________and some ____________ have cloudy urine due to high content of mucus and ____________ ______________________crystals.

Urine Odor Not Very __________________ Strong odor may suggest

_________________ production Male __________, ____________, and

_____________have a very strong urine odor

Urine Specific Gravity

Measure urine ___________________ which is dependent on the number, molecular size, and weight of urine ______________.

Measures the _____________ of urine as it compares to ______________

Specific gravity of water is always 1.000

Specific Gravity “normals”

Species Possible range

Usual range "Adequate” "Indequate"

Canine 1.001-1.065 1.015-1.045 >1.030 < 1.030

Feline 1.001-1.085 1.035-1.060 >1.040 < 1.040

Large Animals 1.001-1.050 1.015-1.030 >1.025 < 1.025

Source: https://ahdc.vet.cornell.edu/clinpath/modules/ua-rout/sg.htm

“Normal” Ranges per Textbook Dog: 1.001 - 1.060 Cat: 1.001 - 1.080 Horse: 1.020 - 1.050 Cow: 1.005 - 1.040

Methods of measuring urine specific gravity ____________________ _______________ _______________

Causes of Altered Specific gravity Increased specific gravity

____________________________ ____________________________ ____________________________

Decreased specific gravity ____________________________ ____________________________ ____________________________ ____________________________

Urine Volume

Influenced by several factors _______________________ _______________________ _______________________

Chemical properties Testing for various chemical constituents of

urine is performed with ________________________ impregnated with appropriate chemicals or reagent tablets.

Be aware of ________________________ Some reagent strips test for

___________________ constituents simultaneously; others exist for ______________________tests

Urine is added to reagent strip via _____________ or the strips are dipped in the urine sample and color changes are noted at specific intervals.

Reagent strips

Chemical Analysis of urine

In vet medicine, the most common chemical properties tested include: ______ _______________ _______________ _______________ _______________ _______________ _______________ _______________

pH

Urine pH is a function of the ____________ ability to regulate H+ and bicarbonate concentration within the blood. Above 7.0 = ____________; below 7.0 = ___________ Normal pH (dog and cat) = 6-7

If too acidic or too alkaline, specific _____________ or ___________ can form

pH of samples left standing open at room temp. tends to _______________ from loss of CO2 Delays in reading reaction may lead to color changes

and false readings

pH pH of urine depends largely on __________. ________________ urine is usually found in

animals on _________ diets; high-protein cereal diets or diets of animal origin cause __________ urine.

_________________ normally have alkaline urine; _______________acidic urine; _______________ either acidic or alkaline depending on what was ingested.

pHAcidic Urine

Metabolic or respiratory ________________

High ___________diet Vomiting Severe ____________ Fever _________________ Prolonged exercise Urinary acidifiers

Alkaline Urine Metabolic or respiratory

________________ Bacterial infections Renal tubular acidosis Purely

______________ diet

Protein

Usually absent or present only in ___________ amounts in normal urine obtained by ___________________ or ___________________

______________ samples or those obtained by expressing the bladder may contain small amount of protein resulting from __________________ that may contaminate urine during its passage along the urinary tract.

Protein Trauma to urinary tract from

__________________, catheterization, or bladder expression may cause sufficient _______________ to cause a trace of _____________ in the urine.

Protein levels in urine can be measured by reagent test strips, and urine protein/creatine ratio (UPC).

Protein Reagent strips (______________) measure protein

by progressive color changes on the reaction pad. Primarily detect ________________ False ________results may occur in _____________

urine depending on diet, urinary tract infection, or urine retention (urethral obstruction)

Only used as a _______________ tool for proteinuria ________ ratio can help confirm significant

amounts of protein in urine Sample is centrifuged and supernatent is used Ratio is obtained by dividing protein concentration by

creatinine concentration Use to confirm _________________ findings on dipstick Do not perform if bacteria in urine.

Protein Very __________ urine can yield false negative

because the concentration may be ________ the sensitivity of the testing method.

______________ proteinuria may result from a temporary increase in glomerular permeability, allowing excessive protein to enter filtrate May be found with ______________ exertion,

_______________________, or convulsions Occasionally a small amount of urine protein is found

after __________________, during the first few days of life, and during _____________.

Proteinuria In most cases, proteinuria

indicates disease of ____________ tract, especially the ________________

Non-renal: inflammation and/or hemorrhage of urinary or urogenital tract

Renal: _______________ disease, glomerulonephritis, amyloidosis, or _______________ syndrome

Pre-renal: Shock, _________ disease, ____________, increased physical exercise; overflow of a transient high concentration of protein in ______________ blood

Glucose Presence of glucose in urine is known as

________________ or _________________ Glucose is filtered through the

___________________ and resorbed by the proximal tubules.

Glucose is __________ normal in urine. Glucosuria usually does not occur in normal

animals unless the _________ glucose level exceeds the ___________ threshold

Renal threshold in dogs = 180 mg/dL; cats 300 mg/dL

Glucose False-__________ results for glucose may be seen

after use of various drugs, including Vitamin C (_____________ acid), morphine, aspirin, _____________ and other antibiotics.

Most reagent strips detect only ____________, not all sugars.

Glucosuria A high __________________ meal may lead to

blood glucose levels exceeding the renal threshold.

Fear, excitement, or _____________, especially in _________, often causes ____________________ and ________________ as a result of ______________________release.

Glucosuria often occurs after IV administration of fluids containing ______________ and occasionally after general __________________.

Glucosuria Diabetes mellitus is a condition in

which the body is unable to absorb and utilize blood _______________ efficiently. As a result, increased levels of glucose may be seen in the blood (hyperglycemia) and in the urine (glucosuria).

__________________ disease and _____________________ are also conditions associated with glucosuria resulting from sustained or marked transient hyperglycemia.

Ketones Ketones are chemical compounds normally

produced during _________ metabolism. They include acetone, acetoacetic acid, and beta-hydroxybutyric acid.

_________________ strips are most sensitive to ___________________ acid and mildly sensitive to _____________. However, they do not detect beta-hydroxybutyric acid which is the ketone primarily responsible for producing __________________.

Ketones are not normally found in urine; they are absorbed by the _____________ tubules. Excessive production leads to urinary excretion of ketone bodies.

Ketonuria is usually present before ____________________ can be detected.

Ketones Conditions characterized by altered _________________

may result in an excessive amount of fat ___________________ to provide energy.

Problems develop when excessive ketones are produced.

Ketones are __________, causing ________ depression and ________________.

Acidosis resulting from ketonemia is _______________________.

Ketonuria frequently occurs in animals with __________________________ (diabetic ketoacidosis).

Ketonemia with ketonuria also occurs with high-______ diets, _________________, fasting, long-term ________________, persistent fever, and impaired ______________function.

Bile Pigments

Bile pigments commonly detected in urine are ________________ and ____________________.

A small portion of __________________ bilirubin may be excreted through the kidneys.

The intestinal tract converts conjugated bilirubin to __________________________ to be excreted by kidneys and in feces.

A ________________ produced urine sample is essential for evaluation.

Bilirubin In ____________ (especially males), bilirubinuria is

common under ______________ conditions. 1+ to 2+ bilirubin with bilirubin crystalluria may be seen in

very ______________________ urine of normal dogs. Any bilirubinuria detected in ________= significant Bilirubinuria usually precedes

______________________ (urine = more ________________________ than plasma)

Bilirubin is __________________ sensitive. Any delay in processing can yield false _____________.

BilirubinuriaCommon Causes: ______________________ ______________________ _____________________ or

_____________________ hemolytic disease

______________obstruction

Urobilinogen Most is excreted in _______________; a small

amount is excreted by _________________ into the urine.

Urobilinogen in a urine sample is considered ________________.

Reliability of screening tests is _________________ because of instability of urobilinogen in urine.

Normally, no urobilinogen is detected in urine of animals.

Correlation between increases or decreases in urine urobilinogen and liver disease in animals is poor.

Urobilinogen Increased values

_____________ dysfunction hepatic ________________ excessive __________ breakdown increased urobilinogen production re-absorption (i.e. a large hematoma) _____________________

True absence or Very Low values failure of ___________ production obstruction of bile passage

Nitrites The nitrite portion of the dipstick analysis has limited

value in veterinary medicine. This is due to the high number of false ________________ test results in small animals.

Nitrites occur in urine during some _________________ infections. In order to achieve an accurate positive test result, the urine must have been retained in the bladder at least ____ hours.

A positive test indicates a bacterial infection. Gram negative __________ are more likely produce a positive test response.

Negative test results do not _____________ infection. The urinary tract infection may involve organisms that do not convert nitrites, or the urine may not have been held in the bladder greater than 4 hours.

Blood Tests for blood in urine detect ______________,

___________________, and myoglobinuria ___________________________ is usually a sign

of disease causing bleeding somewhere in the urogenital tract.

_________ cells (shells of _________ RBCs) may be seen if the source of hemoglobin is lysis of RBCs.

Moderate to large amounts of blood impart a cloudy ______, __________, or __________ color to urine

Similar colors, but with a _______________ appearance that remains after centrifugation, indicate __________________________.

Blood Hemoglobinuria is usually

caused by _____________________ hemolysis.

If urine is very _________ or very ____________, hemoblobinuria can originate from __________ of RBCs in the urine after excretion.

Blood

Urine containing _____________ is usually very dark _________ to almost black in color.

Severe ____________ damage causes myoglobin to leak from muscle cells into the blood.

Distinguishing myoglobinuria from hemoglobinuria can be difficult.

_______________ and _________________________ suggesting muscle damage help to differentiate.

Hematuria (blood in urine)

Chemical impregnated into pad on strip detects __________ groups found within hemoglobin and myoglobin.

Therefore, a positive test may indicate __________________ (confirm with microscopy) or hemoglobinuria or myoblobinuria.

Leukocytes Presumptive evidence of WBCs in urine may be

obtained with reagent strips. Designed to detect ________________________

Enzyme present in all WBCs except __________________________

Many false-negative reactions occur Especially ______________ Glucosuria, elevated ________, certain antibiotics

(tetracyclines) False-positive reactions occur with ________

Old samples, fecal contamination Microscopic evaluation necessary to confirm a positive result

Microscopic examination

Microscopic examination of urine _________________ is an important part of a complete u/a, especially for recognizing diseases of the urinary tract.

With the exception of __________ and ___________ urine, normal urine of domestic animals does not contain a large amount of sediment.

Microscopic examination Examine sediment while urine is fresh

because _________________ will multiply if allowed to stand at room temp. for a long period of time.

Urine collected via ________________ is best for microscopic exam

Sediment may be examined __________ or ______________ Stains often introduce ________________

into the sediment, particularly precipitate material and bacteria.

Possible Constituents of Urine Sediment

_____________________ _____________________ _____________________ _____________________ _____________________ _____________________, parasites, or ova Miscellaneous

Mucus threads, ____________________, fat droplets, other __________________

Erythrocytes May have several different appearances depending on

urine ____________________, ____, and time elapsed between ________________ and ______________________

In a fresh sample, RBCs are small, round, usually smooth edged, somewhat ________________, and yellow or orange May be colorless if _____has diffused during standing

In _____________________ urine, RBCs may shrink and _______________.

In ____________or _____________ urine, RBCs swell and may __________ Lysed RBCs may appear as colorless rings (shadow or ghost

cells) and vary in size.

Various RBCs in Urinalysis

Leukocytes WBCs appear _______________ and can appear

as a dull gray or greenish-yellow Identified in sediment by their characteristic

________________ or ____________________ of the nucleus

____________ are found in urine of animals without urinary or genital tract disease

WBCs ___________ in concentrated urine and ____________ in dilute urine

Finding >__-__ per HPF indicates an _________________ process somewhere in urinary or genital tracts

______________= excessive WBCs in the urine

Leukocytes in Urinalysis

Epithelial cells A few epithelial cells in urine are considered

______________ and occur from normal sloughing of old cells.

Three types of epithelial cells are found in urinary sediment: ______________, __________________, and ___________.

Epithelial Cells Squamous epithelial cells

Derived from the distal _______________, vagina, vulva, or _________________

Presence = not _______________________

Transitional Epithelial Cells

Transitional epithelial cellsDerived from the _______________, ureters, renal ____________, and proximal _________________.Increased numbers suggest ______________ or _________________________.Also may be seen with _________________________.

Renal Cells _______________ epithelial

cells observed in urine. Originate in the renal

________________ and are only slightly larger than __________.

Generally round and contain a large ____________ and nongranular or finely granular cytoplasm.

________________ numbers occur in diseases of kidney parenchyma.

Renal Epithelial cells

Casts In the renal ____________, secreted protein

precipitates in ___________ conditions and forms casts shaped like the _______________ in which they form.

Commonly classified on the basis of appearance as _____________, _______________, _______________ (RBCs and/or WBCs), _________________, ___________, _________, and ______________.

Type depends in part on how quickly the ________________ is moving through the tubules and how much tubular _______________ is present

Cast formation

Casts All are ___________________ structures with

_________________ sides; width is determined by width of the _____________ in which they are formed.

Any cells or structures in the area may also be incorporated into casts, imparting the morphologic features that allow them to be identified

Dissolve in ____________ urine (make sure sample has not become alkaline from standing too long)

May be disrupted with high-speed __________________________ and rough sample handing

Casts

Hyaline Casts

Hyaline casts are _________, colorless and sometimes _________________.

They are composed only of _____________. Hyaline casts seen can indicate the mildest

form of renal ________________, but can also be seen with ____________, poor renal _________________, strenuous _______________ or general ___________.

Hyaline casts

Granular casts

Granular casts are _______________ casts that contain _________________.

These are the most common type of casts see in animals.

The granules are from _____________ cells, __________, or _________ that become incorporated and then degenerated.

Granular casts are seen in cases of acute __________________.

Granular cast

Epithelial casts

Epithelial casts most commonly result when disease processes such as ________________, infarction, or _____________________ cause degeneration and necrosis of tubular _________________ cells.

A common scenario is the patient with severe _____________________. The resulting casts are flushed out of the tubules in urine produced following _____________________ with fluid therapy.

Epithelial casts

Leukocyte casts

Leukocyte casts contain ________, predominantly _______________________________.

The presence of white blood cells and leukocyte casts indicates _____________________ in the renal tubules.

Leukocyte cast

Erythrocyte casts

Erythrocyte casts are deep ____________ to ______________ in color.

These casts form when _______ aggregate within the lumen of the tubule.

Erythrocyte casts indicate ___________ bleeding. The bleeding may be from hemorrhage due to

______________ or bleeding disorders or as part of an ___________________________ response.

Erythrocyte cast

Waxy casts

Waxy casts resemble ________________ casts but are usually ____________ with square ends rather than ___________.

They have a ______________ appearance. These casts are ______________ or gray

and are highly _________________. These casts indicate severe or chronic

_______________________ of the tubules.

Waxy casts

More Waxy Casts

Fatty casts

Fatty casts contain droplets of _______ that appear as ____________ bodies.

These casts are commonly seen in ________ with ___________ disease.

Occasionally seen in ______________ dogs.

Fatty casts

A: Hyaline cast;B: Fatty cast; C: Hyaline to finely granular cast; D: Cellular cast; E: Cellular to coarsely granular cast; F: Coarsely granular cast; G: Finely granular cast; H: Granular to waxy cast, I: Waxy cast.

Crystals (Lab Pro book pp 173-177) Presence in urine is called _________________

Crystalluria may or may not be of _______________ significance.

Certain crystals form as a consequence of their elements being secreted into the urine by ______________ renal activity or as a consequence of metabolic diseases

Type of crystals formed depends on urine ____, ______________________ and __________________, and solubility of elements

Pg. 174 in LP book

Crystals

Crystals are generally reported as __________________, _________________, or __________.

Although crystals and uroliths are often identified based on ____________________ characteristics, the only definitive methods to identify crystals are __________ diffraction and _________________ analysis.

Struvite crystals

Typically resemble ________________ or __________; but may take other shapes

Sometimes referred to as: _______________________________________ _______________________________________ 6 to 8 sides = ______________

Found in ____________ to slightly ______________ urine.

Struvite crystals

The most ________________ type of crystals of both _______and ________.

Often seen in urine from clinically __________________ individuals.

Urinary tract infection with urease-positive ________________ can promote struvite crystalluria (and urolithiasis) by raising urine ______ and increasing free __________________.

Struvite Crystal

Struvite Crystals

Amorphous phosphate crystals Common in ________________ urine and

appear as a granular _____________________.

Similar in appearance to amorphous urate crystals; however, amorphous phosphate crystals lack ____________.

Amorphous phosphate crystals

Calcium carbonate crystals

Common in healthy ______________ and ________________

_____________ with many lines radiating from the centers or can appear as large granular masses.

Also may have a “dumbbell” shape (not common)

________________ to ______________ urine

Calcium carbonate crystals

Urate and uric acid crystals Amorphous urates (Na, K, Mg, or Ca salts) tend

to form in __________ urine, and may have a yellow or yellow-brown color.

Uric acid crystals are not common on small aminmals, but DO commonly occur in __________________ and _______________ due to their body’s inability to process purines (from certain types of meat).

Formation is most common in ___________ urine.

Urate and uric acid crystals

Figure 5-27 A, Amorphous urate crystals. A cotton fiber (contaminant) is trapped within the crystals (arrow). B, Uric acid crystals. These are not commonly found in small animals except for dalmatian dogs. C, Sodium urate crystals. May be found in association with ammonium biurate uroliths. A calcium oxalate dihyrate crystals is also present (center).

(From Raskin RE, Meyer DJ: Atlas of canine and feline cytology, St Louis, 2001, Saunders.)

Ammonium biurate crystals

Ammonium urate (or biurate) crystals generally appear as brown or yellow-brown ______________ bodies with irregular protrusions (”______________________").

Formation is favored in ______________ to _________________urine.

Both __________________ and ___________________ are predisposed to urate urolithiasis. They are rarely, if ever, seen in urine from normal cats or dogs of other breeds.

Ammonium biurate crystals

Calcium oxalate crystals

Calcium oxalate crystals are formed in acidic and neutral urine and may be seen in small numbers normally in dogs.

There are two distinct formations: Calcium oxalate monohydrate Calcium oxalate dihydrate

The urine of animals poisoned with ethylene glycol often contains large numbers of the monohydrate crystals

Calcium Oxalate Monohydrate May be small and “___________” shaped,

can also appear as a slat from a picket fence. Generally form in _________pH urine, but

are a key indicator if an animal is experiencing ______________________ toxicity!

Calcium oxalate monohydrate crystals

Calcium Oxalate Dihydrate

Generally appear as small _____________ with a visible “_____” across the top of the crystal.

Most often form in _________ and __________ urine.

Are commonly seen in small numbers in ____________ and _____________.

If seen in large numbers, can indicate ________________ formation.

Calcium Oxalate Dihydrate Crystals

Tyrosine crystals

Dark, ___________ -like projections; highly ________________; often found in small clusters

Not commonly seen in dogs/cats Associated with ____________ disease Form in _____________ urine.

Tyrosine crystals

Cystine crystals Form in _____________ urine. Often aggregate in ________________. Presence may be an indication of cystinuria, a

______________ metabolic disorder involving defective renal tubular __________________ of certain amino acids including ___________. Sex-linked inheritance is suspected since ________ dogs

are almost exclusively affected. Many breeds, as well as mixed breeds, have been reported affected .

Renal function otherwise appears to be normal and, aside from a tendency to form uroliths, the defect is without serious consequence.

Cystine crystals

Optimal pH for crystal formation

Microorganisms, parasites, ova A variety of microorganisms can be found in urine sediment, including _____________, __________, and ___________________.

Normal urine collected by __________________ or _______________________ does not normally contain bacteria and is considered ____________.

Bacteria can be identified only under ______________ magnification May be round (_______) or rod shaped (_______), usually

refract light, and appear to be quivering as a result of __________________ movement.

Are reported as few, moderate, many, or __________.

Bacteria A large number of bacteria accompanied by a

large number of ________ suggests _______________ and ________________ of the urinary tract (e.g. ___________, pyelonephritis) or ___________ tract (e.g. ______________, metritis, vaginitis).

Bacteria in the urine sample are most significant when also identified within the ___________________ of the WBCs. Submit samples for bacterial _____________&

_____________________testing.

WBCs and Bacteria in urine

Yeast, fungi

Yeast are often confused with __________ or _________ droplets but usually display characteristic _________________. Usually contaminants in urine because yeast infection

of the urinary tract are ________ in cats/dogs. Other fungi may be found (_______________

and usually ________________)

Yeast & other fungi

Ova & Parasites Parasite ova may be seen in urine sediment of

animals with urinary _____________ or because of ___________ contamination at the time of sample collection.

Parasites of the urinary tract include: ______________________ and _________________________________.

Microfilaria of ________________________ may be seen in urine sediment of dogs with circulating microfilaria if __________________ into the urine occurs from disease or ________________ during collection.

Urinary Parasite ovaCapillaria plicaDioctophyma renale

Dirofilaria immitis

Miscellaneous components of urine

Mucus threads are often confused with casts but do not have well-delineated ____________ like casts. Normal in ___________ urine (horses have mucus

glands in renal pelvis and ureter) In other animals indicates _____________ irritation

or contamination of sample with ______________ secretions.

Miscellaneous components of urine _________________ are occasionally seen

in sediment of intact male or recently bred females.

_________ droplets appear as lightly green-tinged, highly refractile, spherical bodies of ______________ sizes. Catheter lubricants, oily surfaces of collection

vials or pipettes Fat in urine = ______________ ; seen to some

degree in cats

Other artifacts

Artifacts may enter the urine sample during _________________, ____________________, or ______________________. _____________, oil droplets, starch granules (glove

powder), ________, fecal material, plant spores, ___________, cotton fiber, __________, glass particles or chips, _______________, and fungi may contaminate urine.

Ova of intestinal parasites may be observed as a result of _______________ contamination.

“Pee End”