Normal urinary continence. Micturition may be defined as function of the lower urinary tract that encompasses both a storage phase and a voiding phase. During the storage phase of micturition, the urinary bladder, acting as a low-pressure reservoir, is relaxed and fills with urine.
Recently, a colleague in private practice asked my opinion about the likely benefit of obtaining an ultrasound-guided percutaneous needle biopsy of the kidney of an azotemic, isosthenuric, 8-year old domestic shorthair cat. She indicated that evaluation of a serum chemistry profile, hemogram and urinalysis revealed findings consistent with idiopathic chronic renal failure.
An 8-year-old spayed female domestic shorthair cat was referred to the University of Minnesota Veterinary Teaching Hospital for evaluation of bilateral nephroliths associated with persistent gross hematuria.
Recently, I received a letter from an inquisitive Dalmatian owner which
stated in part:
"I have a 9-year-old female Dalmatian that has been diagnosed with
a urinary tract infection because of red blood cells found in urine aspirated
from her urinary bladder during an annual physical exam. She does not have
a problem urinating and her urine appears very clear; it is not bloody.
My vet has tried two types of antibiotics (cephalexin first and trimethoprim-sulfa
three weeks later). Even though her urine is not bloody, red blood cells
are still present in the urinalysis. My vet also prescribed a special diet
to prevent urate stones from forming even though no crystals were found
in her urine. Is there a probability of urinary stones even though there
are no crystals in her urine? Is the urinary tract infection persisting
because of stones?"