Section: Veterinary Care In-depth
Diagnosis
Your veterinarian may use radiographs (X-rays) or changes in the types of blood cells (CBC) or enzymes found in the blood (blood chemistry) to evaluate the overall health status of a sick guinea pig.
Radiographs. The most common radiographic change associated with uroliths is the presence of a mineral density in the urinary tract. Uroliths may be easy to visualize radiographically when located in the kidney or bladder but may be difficult to visualize in the urethra. Ultrasound may be used to document the presence of uroliths that are radiolucent or otherwise difficult to visualize radiographically.
Blood work. Blood tests may be normal in guinea pigs with uroliths if the mass has caused minimal irritation of the urinary tract, minimum blockage of urine flow and is not associated with a bacterial infection. If the lining of the urinary tract is damaged or a bacterial infection is present, then the white blood cell count may be elevated (neutrophilia). In guinea pigs with advanced bacterial infections that have passed into the blood stream (called sepsis), the white blood cell may be decreased (neutropenia) with a high proportion of immature cells and/or toxic changes. This finding is associated with a poorer prognosis.
Urinalysis. Visual and chemical analysis of the urine may help determine the type or uroliths that are present and whether or not a bacterial infection is occurring. Culture is usually necessary to specifically identify the type of bacteria that may be present. Cytology (microscopic evaluation of cells) is important in helping to identify the presence of organisms that may be difficult to grow in the laboratory.
Therapy in-depth
Treatment of urolithiasis requires removal of existing uroliths, control of primary or secondary bacterial infections and initiating the necessary changes to prevent recurrence. The precise treatment used by your veterinarian will depend on whether or not your guinea pig is able to urinate and on the type, number and location of the uroliths.
If your guinea pig is unable to produce urine, your veterinarian will first pass a catheter through the urethra to the bladder. If this does not allow for normal passage of urine, then emergency surgery will be necessary.
If your guinea pig is able to pass urine, then your veterinarian may stabilize your pet with fluids and antibiotics (if a urinary tract infection is present) before surgically removing any uroliths.
Uroliths may recur even in properly treated guinea pigs and effective preventative measures have not been reported.
Agents that are used to acidify the urine and reduce the formation of some types of uroliths in other species are not recommended in guinea pigs because their kidneys inefficiently excrete acids.
Your veterinarian is likely to send any urolith removed from your guinea pig to a lab for a compositional analysis. This information can be crucial to implementing changes that will prevent urolithiasis from recurring.
Follow-up Care
Optimal treatment for your guinea pig requires a combination of home and professional veterinary care. Follow-up can be critical, especially if your guinea pig does not rapidly improve.
Make certain you administer all prescribed medications at the appropriate times. Contact your veterinarian immediately if you have difficulty treating your guinea pig as prescribed. If you are having problems, it may be best to hospitalize him to assure that a proper course of treatment is administered.
Some blood may be noted in the urine for a day or two after surgery, palpation or catheterization of the bladder.
Urine output should be carefully monitored several times a day in guinea pigs that are being treated for urolithiasis.
If surgery was performed, check the incision line several times a day (or as directed by your veterinarian) for swelling, discharge or redness. If any of these changes are noted, contact your veterinarian immediately. Use only clean shredded paper as cage bedding. Your veterinarian may recommend hot packing or application of antimicrobial agents to the incision.
Your veterinarian may recommend radiographs, ultrasound, microscopic evaluation of urine and culture of the urine several weeks after completing the recommended therapy for urolithiasis. Uroliths frequently recur in guinea pigs and effective preventative measures have not been reported. Thus, your veterinarian may recommend these same procedures at regular intervals for the remainder of your guinea pig's life to monitor the health of the urinary tract.
