Prostatic cysts (urine-containing prostatic cavitary lesions) are a relatively uncommon prostatic disease of entire and desexed male dogs.
Prostatic cyst often develop secondary to prostatic hyperplasia, where there is variable distension of prostatic acini to form cystic structures, and can form in dogs with no pathological evidence of prostatic disease. They have also been reported in canine cryptorchidism and perineal hernias. A significant proportion have secondary bacterial infections. Histologically these cysts are lined by normal glandular cells.
Clinically affected dogs usually present with prostatomegaly-related signs such as tenesmus, constipation and flattened feces.
Diagnosis is based on rectal examination augmented with abdominal ultrasonography, MRI, and histopathology of tissue samples obtained during exploratory laparotomy. Mineralization of paraprostatic cysts is more common than originally thought, and radiography is an important aspect of proper diagnostic workup to identifying the presence of these cysts.
Accidental diagnoses have also been made during routine cystocentesis, when fluid has inadvertently been collected from the prostatic cyst.
Treatment usually requires broad-spectrum antimicrobial coverage if indicated, such as cefovecin and surgical extirpation of the cysts. These dogs tend to require a more aggressive surgical therapy than percutaneous drainage alone. Ultrasound-guided percutaneous drainage is usually recommended, or exploratory laparotomy with extirpation of the cystic prostate and omentalization or marsupialization of the defect.
- University of Guelph
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