Molly’s Bladder Stones!
Molly is a 6 year old female Cavalier Poodle that presented to the clinic with a history of frequently urinating small amounts for about a week duration.
On presentation she had urine staining around vulval area and painful on palpation of bladder. Urine was collected and showed some abnormalites – bacteria present, alkaline pH and white blood cells. An ultrasound was performed and could visualise stones situated in the bladder.
Normal dog urine is slightly acidic and contains waste products from metabolism including dissolved mineral salts and other compounds. Struvite is a normal component of dog’s urine and will remain dissolved as long as the urine is acidic and is not too concentrated, if this changes then crystals will form.
In dogs, bladder stones usually form as a complication of a bladder infection caused by bacteria that produce an enzyme known as urease. This enzyme breaks down the urea that is normally present in the urine causing an excess production of ammonia; this ammonia production then causes the urine to become alkaline.
Ammonia in the urine also causes inflammation of the bladder. Under these conditions, struvite crystals will precipitate out of solution and collect around any cells or debris that may have formed in the bladder as a result of inflammation.
Female dogs tend to get these types of bladder infections and stones much more frequently than males, probably because their shorter, wider urethra makes it easier for bacteria to pass up the urethra into the bladder.
Molly underwent surgery called a cystotomy, this involves opening up the bladder under a general anaesthetic. The stones where removed successfully and the bladder and urethra were thoroughly flushed with saline.
Molly recovered well after surgery with an indwelling urinary catheter for a couple of days to ensure healing of the bladder without it being stretched too much.
We have sent the stones off to be evaluated in a laboratory to interpret what they exactly are.
Molly needs to be on a special prescription diet to stop the development of more stones in the future.