Post-neutering urethral sphincter mechanism incompetence in female dogs

Abstract

Female dogs neutering is a routine surgery that aims to prevent diseases as well as to help populational control. Urinary incontinence is one of the most significant unwanted consequences following the procedure. Pharmacological treatment is recommended for such case, and alpha-adrenergic and estrogenic drugs have been the most frequent choices reported in literature. Besides, tricyclic antidepressants are also able to control clinical signs. The exact mechanism involved with this condition is not yet fully understood. Estrogen deficiency with a subsequent loss of urethral tonus is believed to trigger clinical signs. However, it is possible that other factors such as gonadotropins and gonadotropin-releasing hormone levels may play a part on this complex mechanism of the post-neutering urinary incontinence.

A castracao de femeas caninas e uma cirurgia de rotina que visa principalmente a prevencao de doencas e o controle populacional da especie. Ela nao e, todavia, desprovida de consequencias indesejaveis, e a incontinencia urinaria pos-castracao e uma das mais significativas. Tratamento medicamentoso e preconizado para estes casos, sendo o emprego dos farmacos α-adrenergicos e estrogenicos os mais frequentemente descritos na literatura. Entretanto, o uso de antidepressivos triciclicos pode ser eficaz no controle dos sinais clinicos da incontinencia. O mecanismo exato que envolve esta afeccao ainda nao e completamente entendido. Acredita-se que uma deficiencia de estrogeno e consequente perda de tonus uretral sejam responsaveis pela ocorrencia dos sinais, mas e possivel que outros fatores como os niveis de gonadotrofinas e de hormonio liberador de gonadotrofinas estejam implicados na patogenia da incontinencia urinaria pos-castracao.