ph 156 dmm

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Rae 3

Urinalysis 11 NOV 2014Department of Medical Microbiology

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I. Bacteria

Normal under these circumstances: Improper collection

Contamination during collection

Not washing the genitals prior to sample collection Normal flora (such as lactobacilli)

o if amount is too abundant, UTI should be considered(due to infection-causing organism such as E. coli )

o presence of WBCs complement this assumption o urine culture may be requested

II. Yeast Cells

Identifying yeast cells: Oval budding cells

Round or ovoid ghosts

Smaller than RBCs DNA of yeast cells can be stained with Sedistain (will

stain them blue to differentiate them from RBCs) Most common: Candida spp.

Presence can indicate: Contamination with vaginal secretion (often observed

with high sugar content) Infection Pathognomonic of pyelonephritis

III. White Blood Cells

Pyuria

General term for the presence of WBCs in urine Neutrophils, in particular

Occurs during fever and after strenuous exercise Normal amount: 0-2/hpf or 3-12/uL Markedly present in almost all renal and urinary tract

diseaseso Cystitis (mild and severe)o Glomerulonephritiso Pyelonephritiso Renal calculio Bladder tumorso Prostatitiso Urethritiso Balanitiso TB of the kidneyo Trauma

IV. Red Blood Cells

May appear: normally shaped,

swollen by dilute urine (only cell ghosts and hemoglobinmay remain) or

crenated by concentrated urine

Swollen, partly hemolyzed RBCs and crenated RBCs aresometimes difficult to distinguish from WBCs

Red cell ghosts may simulate yeast

Dysmorphic RBCs in urine suggests: glomerular disease (such as glomerulonephritis)

passage through abnormal glomerular structure

Hematuria – abnormal numbers of RBCs in urine due to: glomerular damage

tumors which erode the urinary tract anywhere along itslength

kidney trauma

urinary tract stones renal infarcts

acute tubular necrosis

upper and lower urinary tract infection contamination from vagina in menstruating women

trauma produced by bladder catheterization

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V. Mucus Threads

Quite normal

Come from the urinary tract, bladder, urethra, vagina andpenis

Large amounts may indicate bacterial infection, irritationand other problems

Observation of large amounts of bacteria, RBCs or casts andcrystals in the urine sample can help determine if the mucusthreads are indicative of any underlying problems

VI. Squamous Epithelial Cells

Large cells with small round or oval nuclei

Derived from ureters, bladder, outer urethra, other skinsurfaces

Represent possible contamination of the specimen withskin flora

Can indicate inflammation

Vaginal epithelial cells in urine not obtained withcatheterization is normal and of no significance

VII. RBC Cast

Best observed in fresh urine

Usually results in a positive protein test

Brown to colorless with a few to many RBCs within the cast Always considered abnormal

Associated with:

o Glomerulonephritiso Sickle cell diseaseo Subacute bacterial endocarditiso Goodpasture’s syndrome o Congestive heart failureo Vasculitis

May be observed following strenuous exercise, especiallycontact sports; in this case, the urine sediment should returnto normal within 48 hours

VIII. WBC Cast

Mucoprotein casts with incorporated leukocytes

Present in:

o Chronic renal inflammation or renal diseaseo Pyelonephritiso Kidney diseaseo Glomerulonephritis – accompanied by different urinary

sediment findings such as RBC casts Leukocytes enter urinary system through two major

pathways: transglomerular and transtubular

May be confused with epithelial casts (since they are similarin size)

In most cases, granulocytes are incorporated in the casts

Renal epithelial cells: large single nuclei and sometimesincorporated fat globules

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IX. Hyaline Cast

Seen in the urine of healthy persons Also seen in persons with intrinsic renal disease

Increased numbers may be due to:o Strenuous exerciseo Dehydrationo Fevero Diuretic therapyo Proteinuria of renal or extra-renal origino Glomerulonephritiso Pyelonephritiso Chronic renal diseaseo Congestive heart failure

Renal function tests must be conducted first

X. Waxy Cast

Opaque waxlike matrix

Square ends and have frequent notch-like cracksperpendicular to the long axis – related to a long period ofurinary stasis affecting some nephrons

Usually without inclusion or slightly granular; waxy casts withinclusions are occasionally seen

Represent the end-stage of cellular/granular castso With prolonged stasis in the tubule, all cellular granular

debris disintegrates and refractive index of the proteinmatrix increases as the cast ages

o Results in a refractile, brittle, homogenous cast structureusually with convoluted broders and broken ends

Indicates:o Chronic renal diseaseo Severe oliguria or anuria within the nephrono Prolonged renal ischemia and anuria

Will reflect the wide diameter of the pathologically dilatedtubule in which it is formedo Occurs in advanced renal diseaseo Also referred to as “renal failure casts”

XI. Granular Cast

May be small or large May originate from:

o Plasma protein aggregates that pass into the tubules

from damaged glomeruli (includes fibrinogen, immunecomplexes and globulins)

o Cellular remnants of WBCs, RBCs or damaged renaltubular cells

o Fine salt precipitates and lysosomes

With prolonged stasis, large granules in cast may becomesmaller

Seen in both pathologic and nonpathologic conditions

Indicative of:o Glomerular and tubular diseaseso Tubulointerstitial diseaseo Renal allograft rejectiono Pyelonephritiso Viral infectionso

Chronic lead poisoningo Renal papillary necrosis (presence of coarsely granular

casts with hematuria)o Extreme stresso Strenuous exercise

XII. Fine Granular Cast

Contain small refractive granules Appear gray or pale yellow under brightfield

Presence of occasional granular cast is not consideredpathologic

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XIII. Uric Acid Crystals

Extreme pleomorphism in size and in shape

Appear readily in acid urine allowed to stand at roomtemperature

Also appear spear-shaped Associated with gout

XIV. Triple Phosphate Crystals

Also known as magnesium ammonium phosphates, struvite

“envelope form” or “coffin lid” shape Appears in alkaline urine

Associated with bacterial growth and infection with ureasplitting bacteria (e.g. Proteus, Pseudomonas, Klebsiella,Staphylococcus, Mycoplasma)

Can indicate UTI when present in first morning freshspecimen

Usually found with amorphous phostphates, owing to theirlow solubility at alkaline pH

XV. Calcium Oxalate Crystals

Also known as Weddellite, calcium oxalate dehydrate Found in acidic urine and slightly alkaline specimens

Characteristic feature: refractile square “envelope” shapethat can vary in size (also known as the eight-face bi-pyramid)

More complex shapes are possible e.g. dumbbell shape

Indicates:o Hyperparathyroidismo Acute renal failureo Ethylene glycol intoxication

XVI. Sulfonamide Crystals

Found in urine of patients taking/applying:o Baktar (sulfamethoxazol/trimethoprim)o Sinomin (sulfamethoxazol)o Geben cream (sulfadiazine silver)

Look like uric acid or calcium oxalate crystals, but are readilysoluble in acetone

May also look like wheat bundles

XVII. Cystine Crystals

Found in acid urine

Seen as thin, colorless, hexagonal plates Cystinuria – presence of high number of cystine crystals

o Inborn error of amino acid transporto Results in the defective absorption by the kidneys of

cystine the compound builds up in the urineo When the amount of cystine in the urine exceeds its

solubility, crystals formo ↑ cystine, ↑ crystals

When very large numbers of cystine crystals form, theyclump together forming a stone

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XVIII. Tyrosine Crystals

Fine, delicate needles that may be single or arranged insheaves, clumps, or rosettes

May sometimes have a fine, silky appearanced

Formed first as colorless crystals and will take on a paleyellow to yellowish brown color if bilirubin (or a strong dyesuch as Sternheimer-Malbin will dye the crystals purple) ispresent

May appear black when focusing with a microscope

Soluble in alkali, mineral acids, acetic acid, or hear Insoluble in acetone, alcohol, or water

XIX. References

Information from lab demo slidesPictures and tables from:

Strasinger, S.K., di Lorenzo, M.J. (2014). Urinalysis andbody fluids (6th ed.).

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ph 156 dmm

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