An interview with Lauren Adelman DVM, DACVIM:
Dr. Adelman is a veterinary internal medicine specialist located in Vancouver, British Columbia. Dr. Adelman currently works at the Canada West Veterinary Specialists and has a special interest in minimally invasive procedures, gastrointestinal diseases, and urinary disease. You can find her on Instagram @the_tinyvet where she educates pet owners and shares the behind-the-scenes of being a veterinary specialist.
What is IBD?
Inflammatory Bowel Disease is a group of chronic GI disorders characterized by persistent or recurrent GI signs and mucosal inflammation on histologic exam. All areas of the GI tract can be affected and numerous types and forms of IBD exist. Lymphoplasmacytic form is the most common but other forms include those with eosinophilic, neutrophilic, and granulomatous infiltrate. The severity of the disease can also differ. In the most severe cases, inflammation can lead to malabsorption and maldigestion resulting in protein loss through the gut (protein-losing enteropathy).
The key is that IBD is a histologic diagnosis meaning that it can only truly be made on GI biopsies. A lot of people diagnose IBD based on clinical signs alone, however, this is not technically correct.
The cause(s) of IBD is/are unknown but likely involve interactions between the GI microbiome and dysregulated responses in a genetically susceptible individual. The genetic basis of IBD in certain breeds of dogs has been well recognized (I.e. GSD, SCWT, Basenji etc). The role of dysbiosis and abnormal innate immunity have also been recognized.
What are the clinical signs of IBD?
Clinical signs can be quite variable and may include vomiting, diarrhea, weight loss, changes in appetite, flatulence, poor body condition, dehydration, and abdominal pain. In mild cases, weight loss may be the ONLY clinical sign. In severe cases of protein-loosing-enteropathy or PLE, patients may present with pleural and abdominal effusion and be quite sick.
Often are you treating suspected IBD cases or fully diagnosed IBD cases in your practice?
As a specialist, I see referral cases from other veterinarians. Oftentimes these dogs come with a presumptive diagnosis of IBD based on clinical signs alone. The dogs have also usually been placed on several different treatments prior to referral. I would say that of all my “ IBD” cases, about half are suspected and the other half are actually confirmed on biopsy. When I get a case earlier on in the process OR in a very young dog, I encourage endoscopic biopsies to obtain a definitive diagnosis. This gives me the best chance of successfully managing the case moving forward. Also, in older dogs, biopsies can be really important in ruling out other differentials such as lymphoma. Although not common in Vancouver, biopsies can also be important to rule out infectious etiologies like a fungal disease. When I see dogs that have been tried on several different treatments, often including steroids, things can be much more difficult. I usually tell owners in these scenarios the “waters are muddied” so obtaining a definitive diagnosis with biopsy may be difficult.
One thing that is important to realize is that if you biopsy a dog with IBD and a dog with “food-responsive enteropathy” the biopsies are going to look identical. But these are technically 2 separate disorders.
Patients with food-responsive enteropathy (food allergies or intolerance) can only be diagnosed with food elimination trials. Therefore, before pursuing diagnostics such as endoscopic biopsies, it is crucial to me to make sure a patient has been through a strict food elimination diet trial prior to recommending endoscopic biopsies.
How often do you see IBD at your veterinary hospital?
IBD is one of the most common gastrointestinal disorders that we treat in dogs. We see it very commonly.
When pets are diagnosed or suspected of having IBD what type of diet is generally recommended?
Treatment of IBD typically involves therapeutic trials and may consist of a combination of dietary, antimicrobial and immunosuppressive therapy. Some dogs require all the above, with other dogs can be managed on diet alone.
To start, there is no evidence to suggest that one particular diet is the best for patients with IBD. But generally, we approach it as we would in any dog with suspected “food allergies”. As you know, there are no good tests for food allergies manifesting as gastrointestinal signs in dogs. The only way to test is to perform a “food trial”. In the vast majority of cases, when a dog develops a food allergy, it is directed against the meat or protein source in the food. In managing a dog with a potential food allergy, we would therefore want to manage the type of protein fed.
Options include feeding a diet based on a single protein source that we can be sure that the patient has never been fed before (e.g. Rayne Clinical Nutrition kangaroo diet or home-cooked novel protein diet), feeding a diet based on a protein that is unlikely to cause a reaction (e.g. Royal Canin Anallergenic available from a veterinarian, in which the protein is derived from feathers), or feeding a hydrolyzed protein diet in which the protein source cannot be recognized by the body (e.g. Royal Canin Hypoallergenic HP, Hill’s z/d). There is currently no evidence to say which approach is better so it really comes down to the personal preference/experience and the patient (I.e. what they like to eat, comorbidities etc). Any diet transitions should be made slowly over a period of 5-7 days, gradually decreasing the amount of the old diet and increasing the amount of the new diet.
Unlike diet trials for dermatologic disease, diet trials for GI disease are MUCH shorter. Generally we can get an idea within 2 weeks if the diet is going to be appropriate.
Home cooked diets are also a great option for novel protein diets. One of my favourite diets is “STP” (sweet potato, tilapia and pasta) diet which I balance using BalanceIT.com. I find this diet to be highly palatable and it has the added benefit of being markedly fat restricted. So it is really great for dogs with IBD and concurrent lymphangiectasia (think Yorkies) and also for dogs with concurrent fat responsive conditions like pancreatitis (think Schnauzers with IBD). If you want a hypoallergenic diet that is fat restricted that is not home cooked, your best bet is Purina HA. It has the lowest fat of any of the hydrolyzed protein diets. Rayne low fat kangaroo is another option if you are going the novel protein route.
What type of macro composition is ideal for dogs with IBD?
I addressed that above a bit. There is no “one size fits all”. It really depends on the dogs underlying condition (I.e. mild IBD vs PLE, presence/absence of lymphangiectasia and comorbidities). I would say that a LOT of these dogs require low-fat diets. In these cases I try to stick with <20-25% fat ME.
I’ve read that the macro composition recommendation may change depending on the area of the gastrointestinal tract that is affected – is this true?
This is not something I am aware of but maybe it is just reflecting where certain conditions usually are I.e. lymphangiectasia in the duodenum?
Are there certain ingredients dogs with IBD should avoid?
The common protein allergens – chicken and beef. Additionally, if the dog is immunosuppressed (prednisone and/or other second agents) as part of their treatment, I would advise against raw diets as the consequences of any contamination are that much more severe. I have treated my fair share of bacterial gastritis cases in patients on raw food and if the patient is immunosuppressed, the consequences could be deadly.
I have read about one study done on Cats with IBD where they were fed raw and stool quality improved, do we have any studies in dogs that show that a prey-model raw diet to be a good option for dogs with IBD?
Very cool study but it is important to note that it is not yet in a peer-reviewed journal. So I think we need to take this with a grain of salt. I wouldn’t use the results of this study to say that raw diets are better for cats (and dogs) with IBD. Further research including placebo-controlled randomized controlled clinical trials that are blinded are needed. I am not ruling out the possibility, I just think more research is needed. However, as I mentioned above, I would NOT recommend raw diets in dogs on immunosuppressive medications.
Do you find better nutritional management of IBD in dogs with one type or brand of diet more than others?
No. I think it depends on the individual pet and their preferences. Common diets I use are RC Hypoallergenic HP, RC Hypoallergenic SP, Anallergenic, Hill’s z/d, Purina HA, Rayne Kangaroo low fat, home-cooked STP diet, nutritionist formulated/balanced diets.
Which I select first depends on what I know has already been tried (oftentimes that knocks a good 2-3 off the list), what type of food they prefer (canned, kibble or home-cooked) and what might be available.
What types of supplements are good options for dogs with IBD – fish oil, probiotics, herbs etc?
We don’t have solid evidence to support most supplement use in dogs with IBD aside from probiotics. The positive effect of probiotics is likely due to the fact that some of these dogs have a degree of secondary dysbiosis. There are many that would, however, consider “probiotic-responsive enteropathy” as a separate degree entity from IBD. I think oftentimes these various forms of chronic enteropathy are blended together and so that is why one dog may respond to one thing and not another.
What percentage of dogs will respond to the nutritional management of IBD?
That depends on whether we are talking about suspected or diagnosed cases. I think a lot of the “suspected” IBD dogs are actually dogs with food-responsive enteropathy in which case they can respond very well. However in actual confirmed IBD, I usually find that while diet is an essential part of treatment, it is often not the sole treatment modality needed. These dogs often require some degree of immunosuppressive therapy.
What are the steps taken if dogs are not responsive to nutritional management alone?
Ideally? BIOPSIES. Confirm the diagnosis and start other treatments for IBD (steroids, other immunosuppressives etc).
My big takeaway is if something isn’t working, don’t keep trying to throw the “kitchen sink” at the patient. Take a second and re-evaluate. Referral is always a great option!
Thank you so much Dr. Adelman for taking the time to do this interview, this was such a highly requested topic! So many dogs suffer from gastrointestinal issues and often IBD is at the top of the list when a dog has chronic loose stools. I am sure so many people found this interview valuable to answering those “burning questions” regarding this topic.