Rectal Prolapse - Cat and Dog

Signalment

• No breed predisposition but may occur more often in Manx cats due to anal laxity
• No sex predilection

Description

Rectal prolapse is defined as the protrusion of the rectal mucosa from the anus. It is classified as complete or incomplete. A complete prolapse involves all layers of the rectal wall whereas an incomplete prolapse only involves the mucosal layer.

Any conditions which cause tenesmus will cause rectal prolapse, this includes:

• Gastrointtestinal disese
  • Parasites
  • Tumours
  • foreign bodies
  • Colitis
  • Megacolon
• Urogenital disease
  • Cystitis
  • Prostatic disease
• Perineal hernia
• Dystocia

Endoparasite and enteritis are more common in young animals whereas tumours or perineal hernias are more common in milddle-aged to older animals.

The everted tissue becomes oedematous, which prevents retraction back into the pelvic canal. The exposed tissue is vulnerable, which leads to inflammation, ulceration and congestion.

Diagnosis

Clinical Signs

• Protrusion of an elongated, cylindrical mass from the anus. It is vital to differentiate a rectal prolapse from an ileocolic intussusception. This can be done by passing a probe adjacent to the anus. With rectal prolapse, the probe cannot be passed.

Laboratory Tests

There are no specific tests.

Diagnostic Imaging

This may be used to identify the cause of the prolapse.

References

• Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition) W.B. Saunders Company.
• Hall, E.J, Simpson, J.W. and Williams, D.A. (2005) BSAVA Manual of Canine and Feline Gastroenterology (2nd Edition) BSAVA
• Nelson, R.W. and Couto, C.G. (2009) Small Animal Internal Medicine (Fourth Edition) Mosby Elsevier.