Uric acid, calcium monohydrate, calcium phosphate, and triple phosphate normally are present in the urine.
Certain foodstuffs, dehydration, alterations in urine pH, and changes in temperature can cause supersaturation of the above compounds leading to physiologic crystalluria.
The presence of urate crystals is not always indicative of gout.
Vegetarian diets make urine alkaline, decreasing crystals in the urine.
Leucine or tyrosine crystals in the urine can predict progressive liver damage.
Bilirubin crystals in the urine is associated with severe liver disease, yellowish-brown needles attached to cell surface, and is asymptomatic.