Crystals

Question 1

Urinary crystals formation

Answer 1

Salts, medications, metabolites
low temps -> better precipitation
as concentration increases the ability to remain in solution decreases
variable pH

Question 2

Disease associated with crystal formation

Answer 2

Liver disease
inborn errors of metabolism
renal disease
renal calculi

Question 3

Urate Amorphous crystals

Answer 3

Not clinically significant
acidic urine
occur during refrigeration
Ca, Mg, Na, K urates
sediment is pink
soluble in heat and alkaline

Question 4

Phosphate amorphous crystals

Answer 4

Alkaline urine
phosphates and Calcium
sediment white/grey
soluble in acetic acid

Question 5

Uric acid Crystals

Answer 5

Acidic Urine
Normal in low concentration
Associated with increased purines & nucleic acids
Soluble in alkali, heat

Question 6

Uric acid crystal diseases

Answer 6

Gout
Acute Febrile Conditions
Chronic Nephritis
Lesch-Nyhan syndrome

Question 7

Uric acid Identification

Answer 7

Barrel, Rhomboid, Rosette
Birefringent (florescent in polarized light)

Question 8

Calcium Oxalate Crystals

Answer 8

Acidic to slightly alkaline pH
soluble in high molarity HCL
Shapes: dumbbell, rectangular, envelope, ovoid

Question 9

Calcium Oxalate diseases/conditions

Answer 9

Foods high in oxalic acid
Major component of kidney stones

Pathologic conditions: Kidney stones, oxalic acid poisoning, Liver disease, antifreeze poisoning

Question 10

Calcium oxalate crystal associated with antifreeze poisoning

Answer 10

Long monohydrate form
don’t confuse with hippuric acid

Question 11

Hippuric Acid crystals

Answer 11

Colorless 6 sided prisms, needles or rhomboid plates
acidic to slightly alkaline urine
soluble in: alkali, hot water
does not polarize light

Question 12

Hippuric acid conditions/disease

Answer 12

Rare
High fruit/vegetable diet with benzoic acid
liver dysfunction. possible toluene exposure

Question 13

Amonium Biurate crystals

Answer 13

“Thorny apples”
Alkaline urine
Soluble: acetic acid

Question 14

Amonium biurate crystal disease/conditions

Answer 14

only significant in freshly voided urine
associated with old/improperly stored urine

Question 15

Calcium Carbonate crystals

Answer 15

Alkaline urine
dumbbell, spherical, granular
soluble: Effervesces with HCL and acetic acid

Question 16

Calcium carbonate crystal associations/disease

Answer 16

Don’t confuse with yeast. Yeast -> Acidic urine. Calcium Carbonate -> Alkaline

Question 17

Calcium Phosphate crystals

Answer 17

colorless flat plates, rosettes, wedge shaped prisms
Alkaline urines
soluble: dilute acetic acid

Question 18

Calcium phosphate associations/disease

Answer 18

Normal urine, but may indicate kidney stones

Question 19

Triple Phosphate crystals

Answer 19

“coffin lid”
Alkaline urine
soluble: acetic acid
Birefringent

Question 20

Triple phosphate crystals association/disease

Answer 20

Bacteria that split urea and CO2

Question 21

Cystine crystals

Answer 21

Thin, colorless, Hexagonal shapes
Acidic urine
Soluble: HCL, NaOH, NH4OH
Do not polarize light

Question 22

Cystine Crystal disease/associations

Answer 22

Cystinuria
Most frequent cause of kidney stones in children

Question 23

Cholesterol crystals

Answer 23

clear flat plates with a corner notch
Acidic urine
soluble: chloroform, ether
polarizes light

Question 24

Cholesterol crystals associations/disease

Answer 24

excessive tissue breakdown
chyluria due to lymph drainage obstruction

Question 25

Tyrosine crystals

Answer 25

Very rare colorless to yellow brown fine needles with sharp points acidic urine soluble in: HCL, NH4OH Bilirubin test positive

Question 26

Tyrosine crystals association/disease

Answer 26

severe liver disorders frequently seen with leucine crystals

Question 27

Leucine crystals

Answer 27

Spheroid with concentric rings acidic urine soluble: NaOH, hot water bilirubin positive

Question 28

Leucine crystal disease/associations

Answer 28

severe liver disorders MSUD Viral Hepatitis

Question 29

Bilirubin crystals

Answer 29

Yellow brown needles sometimes attached to cells acidic urine soluble: acetic acid, HCL, NaOH, Acetone

Question 30

Bilirubin crystals disease/conditions

Answer 30

severe liver disorders patient history, presentation of jaundice

Question 31

radiographic contrast dye

Answer 31

Flat needles or sheaves Can be confused with cholesterol, tyrosine, sulfonamides

Question 32

Radiographic contrast dye findings

Answer 32

Specific gravity usually >1.035 highly birefringent Patient history valuable

Question 33

Sulfonamide crystals

Answer 33

Sulfonamide antibiotics acidic urine soluble: acetone and alkali flat needles, Sheaves, or spheroids

Question 34

Sulfonamide Crystals confusion

Answer 34

Can be confused with leucine, tyrosine, bilirubin

Question 35

Sulfonamide crystal associations/disease

Answer 35

Dehydration (can cause damage to the nephron) Kidney stone formation

Question 36

acyclovir crystals

Answer 36

Anti-viral med neutral to alkaline pH confused with tyrosine crystals

Question 37

Ampicillin

Answer 37

Large doses of ampicillin without adequate hydration colorless needles that form bundles

Question 38

Talcum powder

Answer 38

flat sheets. irregular and rocky

Question 39

Starch artifacts

Answer 39

Cat buttholes Pseudo maltese cross when polarized

Question 40

Oil/air bubbles

Answer 40

Highly refractive confused with RBCs

Question 41

Trichomonas vaginalis

Answer 41

Most common parasite pear shaped flagellate, undulate membrane. Motile in a fresh sample

Question 42

Giardia Lamblia

Answer 42

Intestinal parasite Appears in fecal contamination The parasite that looks back at you