USE STRICT HAND HYGIENE WHEN HANDLING AFFECTED ANIMALS AS INFECTIOUS CAUSES SUCH AS CAMPYLOBACTER MAY BE TRANSMITTED TO HUMANS.

  1. If your pet is lethargic, inappetent, depressed, has other signs of trauma or pain on defecation, seek veterinary attention immediately.
  2. If your pet is on anti-inflammatory medication such as steroids or non-steroidal anti-inflammatory drugs, discontinue the medication and seek veterinary attention immediately.
  3. If a large volume of blood is passed, seek veterinary attention immediately.
  4. Infant pets that have blood in their stool should always be checked by a veterinarian.
  5. If worms are present in the stool and the animal is otherwise bright, worm with an appropriate wormer according to the manufacturerís instructions.
  6. If your pet shows no other signs of illness and there is a small amount of blood in the stool, you can add fibre to the diet (for example, ¼ – ½ teaspoon of bran or psyllium husk, or mashed pumpkin), or alternatively use a commercial high-fibre diet.
  7. Where constipation secondary to fur balls is suspected, º teaspoon of cod liver oil or a dose of a commercially available paraffin-based pet laxative once a day for three days may aid in the passage of stool.
  8. Seek veterinary attention if your pet fails to pass a stool within 24-48 hours, or if your pet shows any signs of being unwell.
  9. DO NOT GIVE ENEMAS SOLD FOR USE IN HUMANS TO YOUR PET UNLESS PRESCRIBED BY A VETERINARIAN AS THESE ARE POTENTIALLY HARMFUL.

WHAT IS IT?

Blood in the stool is known as haemtochezia or melena and may appear as blood mixed throughout the stool, at the tail end of stool or, in severe cases, the whole stool may consist of blood.

Haematochezia originates in the colon, rectum or anus and refers to fresh blood.

Melena produces dark, tarry stool due to the presence of digested blood from the upper gastrointestinal tract (the stomach and small intestine).

CLINICAL SIGNS

Signs depend on where in the gastrointestinal tract the blood originates from.

  • Fresh blood on or in the stool
  • Foul, metallic smelling stool
  • Dark coloured, clotted blood (can appear like coffee granules)
  • Worms in the stool
  • Mucus in the stool
  • Straining to defecate
  • Obvious masses or lumps around the anus
  • Pus discharging from the anal glands or perianal skin (just below the anus)

Other signs may include:

  • Inappetence
  • Vomiting
  • Depression
  • Weight loss
  • Pale gums
  • Other injuries (in the case of trauma)

CAUSES

Blood in the stool may be due to diseases of stomach or small intestine, the rectum or colon, the anus, or systemic disease. Common causes are outlined below.

Diseases of the stomach and small intestine:

  • Inflammatory bowel disease
  • Infection (parvovirus)
  • Gastric ulceration
  • Foreign body
  • Stomach or intestinal cancers

Diseases of the colon or rectum:

  • Inflammation (colitis)
  • Infection (campylobacter)
  • Benign growths in the bowel or rectum (polyps)
  • Parasites (hookworms, whipworms, roundworms, coccidia)

Diseases of the anus:

  • Anal gland abscess
  • Anal gland tumour
  • Perianal tumour
  • Perianal fistula
  • Trauma

Systemic disease:

  • Clotting disorders (rat bait poisoning or congenital clotting disorder)

TREATMENT

Treatment depends on the underlying cause. Your veterinarian will perform a full physical examination including a rectal exam, and in some cases x-rays or ultrasound. Blood and urine tests may be recommended to evaluate the systemic health of your pet. Where cancer or inflammatory bowel disease is suspected, biopsies may be indicated. In animals with rectal or anal strictures, balloon dilation may be required.

Dehydrated animals may require intravenous fluids, and anaemic animals may require a blood transfusion. Other treatment may include antibiotics, prokinetics, anti-emetics and pain killers.

REFERENCES

Hall E (2009) Canine diarrhoea: a rational approach to diagnostic and therapeutic dilemmas. In Practice 31:816.

Mansfield CS, James FE, Craven M, Davies DR, O’Hara AJ, Nicholls PK, Dogan B, MacDonagh SP & Simpson KW (2009) Remission of histiocytic ulcerative colitis in Boxer Dogs correlates with eradication of invasive intramucosal Escherichia coli. Journal of Veterinary Internal Medicine23:964-969.

Washabau RJ (1999) Pathogenesis, diagnosis and therapy of feline idiopathic megacolon.Veterinary Clinics of North America Small Animal Practice 29(2):589-603.

Weese JS (2011) Bacterial enteritis in dogs and cats: diagnosis, therapy and zoonotic potential. Veterinary Clinics of North America Small Animal Practice 41:208-309.