Clin Path Lecture 24 Part 1

Collection method matters and there are 3 main methods:

Rare; fungal hyphae or yeasts (via culture or PCR); prototheca; sperm (intact males)

Distal urethra; Polygonal

Mid-stream sample collected from urethra is best; non-invasive technique; does not require restraint

Palpation; Cystocentesis; Catheterization

Strip detect hemoglobin, methemoglobin, myoglobin; intact erythrocytes lysed in pad to produce color/speckled appearance

Marked glucosuria and/or proteinuria will overestimate the USG and thus renal concentrating ability

Immunoglobulin light chains in urine; w/ profound hyperglobinemia +/- leukemia, osteolytic lesions, + hypercalcemia

Normal animals don't have detectable _ in urine; B-hydroxybutyrate (most common), acetoacetate, acetone Ketosis products

Concurrent pyuria expected if clinically sig.; can multiply in urine after collection so factor in time to assessment

Technique can cause iatrogenic hemorrhage; low risk of perforation; do not use if urothelial carcinoma is a concern

Interpreted in light of hydration status, presence of azotemia, + clin signs; dehydration will increase _

Cylindruria (when present indicate tubular disease + reflects acute injury); hyaline, epithelial, lipid, granular

Eggs/oocysts: capillaria/pearsonema sp., Dioctopyma renale (dogs), Klossiella equi (horse)

Form due to precipitation of different kinds of salts; pH influences whether certain types of _ will precipitate

Not considered diagnostically useful in veterinary medicine

Best for urine culture-sterile sample; does not generally require sedation; bladder needs to be somewhat distended

Coagulopathies

Medullary conc. gradient established by: BUN - 50% of conc. gradient, Na+ - 50% of conc. gradient

In urine = bactiuria; not present in health; may be reported as semiquantitative measurement or present/absent

Leukocyte, Hemoglobin or Myoglobin, Waxy

Measured via refractive index and is ratio of a solutions weight to weight of equal H2O volume; estimation of osmolality

Size: <68,000Mr will pass freely; Charge: negatively charged ions + _ are repelled; dogs: (-)trace +1 protein in health

Hemoglobin/Myoglobin does not sediment out and supernatant is pink; Myoglobin (brown) from muscle breakdown; ^ CK

When _ conc. exceed renal threshold = glucosuria; Dogs: 180-220 mg/dL; Cats: 290 mg/dL; Horses/Cattle: 150 mg/dL

Some drugs (sulfonamides) can alter _; Pyrocatechin changes horse urine brown when cold + is not pathologic

Adult equine and rabbit urine is naturally cloudy/turbid due to large amounts of mucus/calcium carbonate crystals

Inflammatory, hyperplastic, or neoplastic processes can increase _ in the sample

Reported as a mean or range per 400x HPF; fewer than 5 per HPF may be physiologic; concurrent positive heme expected

Urine USG is same as serums USG which indicates there is enough tubular damage that tubules cannot dilute or conc. urine

Normal urine is yellow/amber due to urochromes; varies based on conc.; ^ conc. = dark yellow, dilute = light yellow

A minimum of __ of urine is required

Crystalluria; risk factor for urolithiasis but not reliable indicator of urolithiasis; Radiopaque is >3mm (uroliths)

Expected in urine of healthy animals and vary in # based on collection technique; mean or range per 100x LPF

Sample storage can:

Occurs due to proximal tubular damage generally in acute renal diseases; rarely above 1-2+

Cylindrical concretions with round, square, or tapered ends that mirror the tubular segments (loop of henle, DT, CD)

The reagent test strip only detects 2 of the 3 ketones, acetoacetate and acetone

Contents of urine are not stable; best results are achieved with processing within 1 hour of collection

Protein losing nephropathy (PLN) due to glomerulopathy (proteinuria, hypoalbuminemia, edema, hypercholesterolemia)

Have tubular function; nephrogenic diabetes insipidus (nonresponsive to ADH); central diabetes insipidus (ADH deficient)

Ketonuria occurs w/ mobilization of lipids and formation of ketoacids -> ketone bodeis in blood/urine (Ketosis)

Neoplasia, urolithiasis, necrosis

Not expected in urine, except dogs; renal tubules of dogs can conjugate + excrete _; not uncommon to see in conc. urine

Corticosteroid "stress"; excitement; Iatrogenic (IV therapy with dextrose)

Urinary obstruction in cats is most commonly from dried solidified blood (organic matter); not composed of crystals

_ detected by test strip predominantly conjugated (soluble form is serum/plasma); does not detect biliverdin

May require sedation, esp. cats and female dogs; mthod can cause trauma or UTI

Decreases in BUN below reference interval and a serum Na+ level <120 mmol/L can result in ____

Extremely dilute urine may dilute the sediment and thus mask a process

Overflow most commonly due to hypertension or exercise

Fairly sterile; can collect when there is little urine in bladder; epithelial cells can be elavted in sample

Differentiation of malignant vs. nonmalignant should be performed with stained air dried samples; clinical pathologist

_ reagent test pad on chemistry strip is inaccurate; indication of tubular function + kidney's ability to conc. urine

Normal urine is clear; cloudiness/turbudity indicates presence of formed elements (cats, cell, lipid, crystal, bacteria)

Renal pelvis, ureters, urinary bladder, prostatic urethra; round

PLN can occur without nephrotic syndrome, generally nephrotic syndrome respresents advanced PLN

Nephrogenic diabetes insipidus: hypercalcemia, pyometra, liver failure, hypokalemia

Not sterile; can be stressful, esp. to cats; manual bladder expression can cause undesired injury esp. if obstructed

Bilirubin, amorphus, drug associated

Composed of Tamm-Horsfall mucoproteins +/- lipids or cells; low numbers present in health; <2 per LPF; generally hyaline

Generally profound proteinurias; Concurrent hypoalbuminemia

Struvite, calcium (carbonate, oxalate dehydrate/monohydrate, phosphate), ammonium biurate, xanthine, uric acid, cystine

Vascular damage (inflammation, trauma, renal infarcts, toxins (bracken fern); thrombocytopenia/thrombocytopathia

Measured via reagent pad on test strip; more accurate w/ _ meter (rare); interpreted based on species + acid-base status

Glomerular filtration barrier; PT resorbs most proteins that go through; pad detects albumin; interpret in light of USG

Freely filtered; absorbed by PT -> circulation; transient/persistent; glocosuria occurs concurrently w/ hyperglycemia

Type not determined; pyuria = increased leukocyte per HPF in urine; infectious or non-infectious

Diabetes mellitus (unmanaged); Fanconi syndrome (Basenji, Norwegian Elkhound); Renal tubular necrosis or ischemia

Renal tubules lose their ability to concentrate urine at 2/3 or 66% loss

Evaluate sediment for erythrocytes; form yellow supernatant w/ red erythrocyte pellet in bottom; methemoglobin is brown

Bacteria, fungi, parasites

In lymphoproliferative disease (multiple myeloma), leishmaniasis, ehrlichiosis, + babesiosis; via immunoelectrophoresis

Reported as a mean or range per 400x HPF; < 5 per HPF may be physiologic; round, colorless cells with grainy texture

Renal tubules; uncommon, cuboidal to round, may be present in cohesive clumps

Hematuria = increased erythrocyte per HPF in urine sediment; pathologic and iatrogenic