Prostatic hyperplasia

From Dog
Advanced prostatic hyperplasia in a dog[1]

Benign prostatic hyperplasia (prostatomegaly) is a common prostate disease of older, entire dogs.

This disease is a benign, naturally developing, age-related condition in dogs as a result of testosterone-induced hyperplasia of prostatic epithelial and mesenchymal structures[2], with little change in the collagen supportive structures[3]. These physiological alterations can be found in more than 95 % of aged intact male dogs[4].

The process by which the circulating testosterone acts within the prostate to cause hyperplasia is not fully understood[5] but may be related to a chronic inflammatory process.

Clinically affected dogs are older (usually over 5 years of age), entire males with tenesmus, flattened faeces, constipation or hematuria[6].

Diagnosis is relatively easy using rectal examination of ultrasonographic studies. Ultrasound guided biopsy may be required to ascertain a definitive diagnosis.

A differential diagnosis would include prostatitis and prostatic adenocarcinoma.

Treatment usually requires orchidectomy (castration) but hormonal suppression of testicular function with GnRH-depot-analogues such as suprelorin have proven effective[7].

Clinical symptoms of dysuria may be ameliorated with the use of silodosin, a uroselective α-1-adrenergic antagonist[8].

The use of experimental radiation therapy shows great promise but is mainly restricted to large referral practices[9].

References

  1. University of Guelph
  2. Shidaifat F & Lin YC (2012) Testosterone effect on the expression of genes that mediate testosterone metabolism and genes that mediate the effect of those metabolites on the prostate. Life Sci 91(5-6):194-198
  3. Juodziukyniene N et al (2010) Effect of age, hyperplasia and atrophy on collagen parameters in dog prostates. Pol J Vet Sci 13(3):479-485
  4. Renggli M et al (2010) Benign prostatic hyperplasia: treatment options in the dog. Schweiz Arch Tierheilkd 152(6):279-284
  5. Wilson JD (2011) The critical role of androgens in prostate development. Endocrinol Metab Clin North Am 40(3):577-590
  6. Sontas BH et al (2010) Blood dripping from the penis of a German Shepherd dog. Aust Vet J 88(6):242-244
  7. Palm J & Reichler IM (2012) The use of deslorelin acetate (Suprelorin®) in companion animal medicine. Schweiz Arch Tierheilkd 154(1):7-12
  8. Schilit S & Benzeroual KE (2009) Silodosin: a selective alpha1A-adrenergic receptor antagonist for the treatment of benign prostatic hyperplasia. Clin Ther 31(11):2489-2502
  9. Zhao P et al (2011) Three-dimensional conformal radiation therapy of spontaneous benign prostatic hyperplasia in canines. Oncol Res 19(5):225-235