Sediment Constituents (Abnormal Crystals) Flashcards
What is the appearance of cystine crystals?
Colorless refractile hexagonal plates, often laminated. Sides are not always even resembling a six sided stop sign
What is cystine often mistaken for?
Hexagonal uric acid crystals
In which conditions is cystine increased?
Cystinuria and cytinosis
What is the color of cystine in urine?
Colorless
What is the solubility of uric acid and cystine in ammonia?
Soluble
What is the solubility of uric acid and cystine in dilute HCl?
Uric acid: Insoluble, Cystine: Soluble
Which test is positive for cystine?
Cyanide-nitropruside reaction
What is the appearance of cholesterol crystals?
Rectangular plate with notch in one or more corners (staircase pattern)
What type of crystals are seen in refrigeration?
Cholesterol
Cholesterol crystals resemble which other crystals?
Crystals of radiographic dye
In which condition is cholesterol increased?
Nephrotic syndrome
What is the solubility of cholesterol crystals?
Chloroform
What are some other names for radiographic dye?
Meglumine diatrizoate, Renograffin, Hypaque
What is the appearance of radiographic dye crystals?
Flat, four-sided plates, often with a notched corner; other forms include long, thin, prisms, or rectangles
How to differentiate between radiographic dye and cholesterol crystals?
Check patient history, correlate with other UA results (S.G > 1.040 using refractometer)
What is the solubility of radiographic dye in 10% NaOH?
Soluble
What type of urine crystals appear as hay-like and fine, colorless to yellow needles in clumps or rosettes?
Tyrosine
In which condition is tyrosine increased?
Liver disease (more commonly found than leucine)
What is the solubility of tyrosine crystals?
Alkali or heat
What is the appearance of leucine crystals?
Yellow-brown oily-looking spheres with concentric circles and radial striations
What do leucine crystals resemble?
Wagon wheels, tree growth pattern or striations of tree
What can leucine crystals resemble besides tree patterns?
Fat globules
What pattern is seen under polarization with leucine crystals?
Pseudo-maltese cross pattern
In which condition is leucine increased?
Liver disease
What is the solubility of leucine crystals?
Hot alkali or alcohol
What do bilirubin crystals look like?
Clumped granules or needles with bright yellow color
What other form can bilirubin crystals take?
Reddish brown needles that cluster in clumps or spheres
In which condition is bilirubin increased in urine?
Liver disease
What is the solubility of bilirubin crystals?
Acetic acid, HCl, NaOH, acetone, and chloroform
What is the appearance of sulfonamide crystals?
Fan shaped needles, sheaves of wheat, rosettes, arrowheads, petals, round-shaped, whetstones
What can sulfonamide crystals be mistaken for?
Calcium phosphate crystals
How to differentiate between sulfonamide and calcium phosphate crystals?
Calcium phosphate is soluble in acetic acid, Sulfonamide is positive in lignin test and diazo reaction
What can sulfonamide deposits cause in nephrons?
Possible tubular damage
What is the solubility of sulfonamide crystals?
Acetone
What are the forms of sulfonamide crystals?
Brown rosettes or spheres, with irregular radial striations (sulfomethoxazole), yellow-brown sheaves of wheat with eccentric binding (Acetylsulfadiazine and Sulfadiazine)
What is the appearance of ampicillin crystals?
Colorless needles that tend to form bundles following refrigeration
When are ampicillin crystals typically present?
Massive dosage of penicillin
What do hemosiderin crystals look like?
Coarse, yellow-brown granules resembling amorphous urates
What test is positive for hemosiderin crystals?
Rous test (prussian blue stain)
What do acyclovir crystals look like?
Colorless slender needles that are strongly birefringent with polarized light
What is the appearance of indinavir sulfate crystals?
Slender colorless needles or slender rectangular plates, featherlike crystals that aggregate into wing-like bundles
How is indinavir sulfate arranged in urine?
Fan-shaped or starburst forms, bundles, or sheaves
What is indinavir sulfate associated with?
Renal blockage, stone formation in HIV positive individuals
What type of formation is seen in oval fat bodies, fatty casts, fat droplets, starch granules, and cholesterol?
Maltese cross formation
What is the appearance of starch granules?
Spheres with dimpled center (y indentation)
What pattern is seen under polarization with starch granules?
Maltese cross
What is an artifact mistaken as RBCs?
Oil droplets, air bubbles
What is the appearance of pollen grain in urine?
Spheres with cell wall and concentric circles
What is an artifact mistaken for Ascaris lumbricoides?
Pollen grain
What are artifacts mistaken for casts?
Hairs and fibers
What is the fecal contamination artifact in urine?
Vegetable fiber