Why does the type of urine crystal change from one sample to another in the same dog?
Formation of detectable crystalluria is dependent on the temperature, the pH, urine concentration, diet, metabolic abnormalities, drugs, and specimen handling. Some of these factors may be quite variable (ex. the postprandial alkaline tide may result in altered urine pH compared to a fasting sample, changing the diet and/or changing the pH in the sample may alter the type of crystal seen). The best method of avoiding artifactual alterations in the urine sediment is to evaluate the urine specimen immediately after collection, with the sample still at body temperature.
