Common Crystals
A number of in vivo and in vitro factors influence the types and numbers of urinary crystals in a given sample.
In vivo factors include:

  1. the concentration and solubility of crystallogenic substances contained in the specimen,
  2. the urine pH, and
  3. the excretion of diagnostic and therapeutic agents.
In vitro factors include:
  1. temperature (solubility decreases with temperature),
  2. evaporation (increases solute concentration), and
  3. urine pH (changes with standing and bacterial overgrowth).
Listed below are some of the more commonly encountered types of crystals. All of these can be seen in samples from normal animals. Conversely, in certain situations, some of the same crystals can be clinically significant.
Struvite Bilirubin
Ca Carbonate Amorphous
Ca Oxalate Dihydrate

back
Last Updated: Thursday, May 02, 1996