Urine Sediments



Uploaded: 2008-02-08, Updated: 2008-02-08





Associated Conditions


• Size: 7-8 ΅m in diameter

• Pale or yellowish, smooth biconcave disk

• No nucleus or cytoplasmic granules

• Normal: Less than 2 RBC/HPF

• Can originate from any part of the urinary tract

• In females, consider menstrual contamination




• Typically neutrophils (PMN)

• Larger than RBC, 10-12 ΅m in diameter

• Contain nucleus and cytoplasmic granules

• Brownian movement  (“glitter cells”)

• Normal: no more than 2 RBC/HPF

• Can originate from any part of the urinary tract (glomerulus to urethra)

•  Increased In inflammatory processes of the urinary tract (pyuria)



Renal Tubular Epithelial Cells

• Slightly larger than WBC

• Flat, cuboidal or columnar

• One large round nucleus

• Tubular damage, pyelonephritis, ATN, salicylate intoxication, transplant rejection



Transitional Epithelial Cells

• 2-4 times larger than leukocytes

• Round, pear-shaped, tail-like projections

• Large round nucleus







Squamous Epithelial Cells

•  Large, flat, irregular-shaped cells



•  principally from the urethra and vagina








Hyaline Casts

• Tamm-Horsfall protein (very low refractive index)

• Colorless, homogenous and transparent

• Rounded ends

•  most frequently observed

•  can be found in normal urine

•  physical exercise & dehydration




Waxy Cast

• Very high refractive index

• Yellow, gray or colorless

• Smooth homogeneous appearance

• Short, broad with blunt or broken ends

• Cracked or serrated edges

• Severe chronic renal failure, malignant hypertension, diabetic nephropathy



Granular Cast

• Large and coarse granules

• Second-most common type of cast

• Can result either from the breakdown of cellular casts, or the inclusion of aggregates of plasma proteins (eg, albumin) or immunoglobulin light chains

• Significance: chronic renal disease; As with hyaline casts, can also be seen for a short time following strenuous exercise.



Fine Granular Cast

• Fine granules, gray or pale yellow



• Significance same as for granular casts



Red Cell Cast

• brown to tan

• Renal hematuria, glomerular disease (ie, acute glomerulonephritis, lupus nephritis, renal trauma)




White Cell Cast




•  Infection and noninfectious renal inflammation  (ie, acute pyelonephritis, interstitial nephritis & lupus nephritis)



Epithelial Cell Cast


• Stasis and desquamation of renal tubular epithelial cells following tubular damage and necrosis.



Fatty Casts (Oval Fat Bodies)

• “Maltese-cross” pattern under polarized light.



• Fatty degeneration of the tubular epithelium in degenerative tubular disease.



Crystals in Acid Urine




Uric Acid

• Many different shapes, diamond, rhombic prism or rosette

• Yellow or brown


•  Very common

•  Can be normal occurence

•  Associated with increased purine metabolism




Calcium Oxalate

• Colorless, octahedral or envelope

•  Ingestion of oxalate-rich foods: spinach, rhubarb, tomatoes, garlic, oranges, asparagus

•  High intake of ascorbic acid

•  Ethylene glycol poisoning





•  Colorless, refractile, hexagonal plates

•  Of diagnostic importance,

•  Congenital cystinosis or cystinuria





•  Oily, highly refractile, yellow or brown spheroids and concentric striations



•  Clinically significant

•  Maple syrup urine disease, Oasthouse urine disease, severe liver disease

•  Seen with tyrosine in liver disease





•  Large, flat, transparent

•  Notched corners


•  Excessive tissue breakdown

•  Obstructed lymphatic flow

•  Nephritis and nephrotic conditions





•  Very fine, highly refractile needles

•  Black, yellow

•  In sheaves or clusters


•  Severe liver disease

•  Tyrosinosis





•  Fan or sheaf of needles, eccentric binding

•  Clear or brown




Crystals in Alkaline Urine

Triple Phosphate

(Ammonium Magnesium Phosphate)

• Colorless prisms, 3-6 sides, oblique ends

• Coffin lids



• Can be found in normal urines

• Chronic urinary inflammation



Ammonium Biurate

• Yellow-brown spherical bodies with long, irregular spicules




Calcium Phosphate

•  Long thin, colorless needles

• One pointed end

•  Arranged as rosettes or star

• Can be found in normal urines








Schistosoma haematobium

•  Blood fluke egg

•  50 x 150 ΅m in diameter

•  Leukocytes (eosinophils) in background




Yeast Budding

• Smooth, colorless, oval, doubly refractile walls

• Most common, Candida albicans




Yeast Branching




Trichomonas vaginalis


•most frequently encountered parasite




• Round or oval

• Highly refractive, vary in size

• Hexagonal in shape

• Irregular indentation in the center

• "Maltese crosses" under polarization





  • Dr. Allen's lecture "Urinalysis". Oct. 13, 2008.

  • A Handbook of Routine Urinalysis. Sister Laurine Graff. 1983