Ulcerative colitis

From Dog
(Redirected from Irritable bowel)
Emaciated Boxer with ulcerative colitis[1]
Colonoscopy shows a diffusely thickened and ulcerated mucosa (arrow)[2]

Ulcerative colitis (granulomatous colitis) is a common chronic gastrointestinal disease of dogs, especially Boxer breeds, although other large breeds can be affected[3].

This condition appears to be caused by an overly aggressive immune response to luminal commensal bacteria, particularly Bacteroides spp and Escherichia coli[4], in genetically-susceptible dogs[5][6].

An attempt to reproduce colitis in Boxer dogs with Mycoplasma spp isolated from the colon and regional lymph nodes of four affected dogs has been unsuccessful[7]. The predilection for Boxer dogs, with only sporadic cases of this type of colitis reported in non-Boxer dogs, and the absence of a causal infectious agent have led to granulomatous colitis of Boxer dogs being considered a breed-specific, immune-mediated disease of unknown etiology[2].

Underlying bacterial infections are commonly observed, in order of importance:

In this disease, there appears to be dysregulation of normal mucosal immunity, characterised by polyclonal lymphocytic infiltrates which are presumably specific for luminal antigens. Increased mucosal permeability and deranged intestinal motility are common sequelae[10]. The inflammation results in colonic thickening, ulcerations, and distortion of normal glandular architecture[11].

Clinical signs associated with this disease are usually referable to lower bowel disease characterized by weight loss, vomiting, tenesmus, increased frequency of defecation, compensatory polyphagia, diarrhea, palpably thickened colon and, in severe cases, hypoalbuminemia, anemia, hematochezia and melena[12].

Diagnosis is based on presenting clinical signs, ultrasonography, large bowel biopsies and isolation of pathogenic bacteria. Multiple colonic biopsies are characterized by infiltrations of PAS-positive histiocytes in the lamina propria[13][14]. A differential diagnosis would include intestinal parasites, lymphocytic-plasmacytic enteritis, eosinophilic granulomatous gastroenterocolitis, adenoma, carcinoma and lymphosarcoma[15].

Treatment is usually aimed at immunosuppressive agents (e.g. prednisolone), anti-inflammatory drugs (e.g. sulfasalazine)[16] and antimicrobial therapy[17].

Either enrofloxacin alone or in combination with metronidazole and amoxicillin/clavulanate are often used.

Histological improvement following therapy in Boxer dogs with histiocytic ulcerative colitis has been reported[18] and young boxer dogs with relatively mild signs may respond moderately well to medical and dietary therapy[19].


  1. Cornell Vet
  2. 2.0 2.1 Simpson KW et al (2006) Adherent and invasive Escherichia coli is associated with granulomatous colitis in boxer dogs. Infect Immun 74(8):4778-4792
  3. Stokes JE et al (2001) Histiocytic ulcerative colitis in three non-boxer dogs. J Am Anim Hosp Assoc 37(5):461-465
  4. Onderdonk, AB et al (1998) Correlation of cecal microflora of HLA-B27 transgenic rats with inflammatory bowel disease. Infect Immun 66:6022-6023
  5. Podolsky, DK (2002) Inflammatory bowel disease. N Engl J Med 347:417-429
  6. Sartor, RB (2004) Therapeutic manipulation of the enteric microflora in inflammatory bowel diseases: antibiotics, probiotics, and prebiotics. Gastroenterology 126:1620-1633
  7. Bowe, PS et al (1982) Attempts to produce granulomatous colitis in Boxer dogs with a mycoplasma. Can J Comp Med 46:430-433
  8. Van Kruiningen HJ et al (2005) The comparative importance of E. coli antigen in granulomatous colitis of Boxer dogs. APMIS 113(6):420-425
  9. Mansfield CS et al (2009) Remission of histiocytic ulcerative colitis in Boxer dogs correlates with eradication of invasive intramucosal Escherichia coli. J Vet Intern Med 23(5):964-969
  10. Cave NJ (2003) Chronic inflammatory disorders of the gastrointestinal tract of companion animals. N Z Vet J 51(6):262-274
  11. Hostutler RA et al (2004) Antibiotic-responsive histiocytic ulcerative colitis in 9 dogs. J Vet Intern Med 18(4):499-504
  12. Van Kruiningen, HJ et al (1965) A granulomatous colitis of dogs with histologic resemblance to Whipple's disease. Pathol Vet 2:521-544
  13. Tanaka H et al(2003) Histiocytic ulcerative colitis in a French bulldog. J Vet Med Sci 65(3):431-433
  14. German AJ et al (2000) An immunohistochemical study of histiocytic ulcerative colitis in boxer dogs. J Comp Pathol 122(2-3):163-175
  15. van der Gaag I & Happé RP (1989) Follow-up studies by large intestinal biopsies and necropsy in dogs with clinical signs of large bowel disease. Can J Vet Res 53(4):473-476
  16. Hostutler RA et al (2004) Antibiotic-responsive histiocytic ulcerative colitis in 9 dogs. J Vet Intern Med 18(4):499-504
  17. Hostutler RA et al (2004) Antibiotic-responsive histiocytic ulcerative colitis in 9 dogs. J Vet Intern Med 18(4):499-504
  18. Davies DR et al (2004) Successful management of histiocytic ulcerative colitis with enrofloxacin in two Boxer dogs. Aust Vet J 82(1-2):58-61
  19. Churcher RK & Watson AD (1997) Canine histiocytic ulcerative colitis. Aust Vet J 75(10):710-713