New Approaches to Feline IBD

The underlying pathogenesis of feline inflammatory bowel disease (IBD) is believed to be a disturbance in gastrointestinal (GI) mucosal immunity with loss of mucosal tolerance to intestinal antigens, such as commensal bacterial flora or dietary components. Therapy is directed at decreasing GI antigenic stimulation and modulating the local gut immune response. Definitive diagnosis of IBD requires intestinal biopsy. Mucosal biopsies performed via endoscopy are relatively noninvasive and inexpensive, but full-thickness biopsies done by exploratory or laparoscopic surgery are ideal for IBD diagnosis and exclusion of lymphoma. Abdominal ultrasonography can help the clinician choose a biopsy technique. In addition, low serum folate or cobalamin levels suggest intestinal malabsorption and can also be helpful in planning biopsies. Similarly helpful are results of serum feline trypsin-like immunoreactivity and feline pancreatic lipase immunoreactivity tests. Dietary manipulation using a novel protein elimination diet or hydrolyzed protein diet is a critical first step in treatment, and this approach alone has a fairly high efficacy in treating chronic feline GI disease. A 4- to 6-week trial has historically been recommended, but in one elimination diet study, all responder cats improved within 2 to 3 days. That study suggests that shorter (eg, 1-week) trials are acceptable. In cats unresponsive to dietary change, immunosuppressive therapy is still the mainstay of treatment. Prednisolone (preferred over prednisone) is indicated in moderate to severe cases, and treatment with subcutaneous dexamethasone may improve initial response in severe malabsorption cases. In cats with refractory IBD, budesonide, chlorambucil, or cyclosporine may be effective. Other adjunctive or alternative treatments include probiotics, soluble fiber, cobalamin, metronidazole, and omega-3 fatty acids.COMMENTARY: This is a useful review of the spectrum of options available to treat IBD in cats. Rational use of some of the newer approaches, such as budesonide, cyclosporine, prebiotics, and probiotics, is detailed. The mainstay of treatment remains dietary and immunosuppressive therapy, but other approaches are also discussed. The article provides a useful flowchart to explain the progression of steps to manage patients in which treatment has failed. The authors did not discuss the pros and cons of azathioprine for treating feline IBD. The drug is admittedly not without risk in the cat but at a lower dose has been effective. Anybody who treats IBD in cats should read the full article.

Idiopathic inflammatory bowel disease in cats. Trepanier L. J FELINE MED SURG 11:32-38, 2009.