Dietary management of presumptive protein-losing enteropathy in Yorkshire terriers

Prednisolone pharmacokinetics in dogs with protein-losing enteropathy

BACKGROUND

It is unknown if glucocorticoid malabsorption contributes to the approximate 50% treatment failure rate in dogs with protein-losing enteropathy (PLE).

OBJECTIVE

To compare pharmacokinetics (PK) of orally administered prednisolone in dogs with PLE vs healthy controls.

ANIMALS

Fourteen dogs with well-characterized PLE and 7 control dogs.

METHODS

Prospective case-controlled study. Dogs were treated with 1 mg/kg prednisolone PO once daily for approximately 3 weeks. Venous blood samples were collected at set timepoints before and after prednisolone administration on the first (T1) and final (T2) study days. Total and non-protein bound serum prednisolone concentrations were determined using liquid chromatography tandem-mass spectrometry, and pharmacokinetics variables were derived from the drug concentration data. Pharmacokinetics variables were compared between PLE and control dogs and between PLE short-term responders and non-responders.

RESULTS

The PLE dogs had a shorter half-life of the terminal slope than control dogs (harmonic mean of 1.3 vs 1.8 hours; P = .05) whereas the percentage of serum prednisolone that was non-protein bound was higher in PLE dogs than in control dogs (median of 15.7% vs 6.7%; P = .02) at T1. Total prednisolone drug exposures and maximum total serum drug concentrations did not differ between PLE and control dogs at T1 or T2, nor did they differ between short-term responders and non-responders within the PLE population (P > .05 for all comparisons).

CONCLUSIONS AND CLINICAL IMPORTANCE

Overall drug exposures are similar between PLE dogs and healthy controls. Glucocorticoid malabsorption is unlikely to be a common cause of treatment failure in dogs with PLE.

Successful clinical management of canine intestinal lipogranulomatous lymphangitis through exclusive medical and nutritional treatment: four cases (2018-2023)

OBJECTIVES

To describe clinical, ultrasonographic, pathological features and response to medical therapy of four dogs with intestinal lipogranulomatous lymphangitis.

METHODS

Retrospective review of medical records of dogs with an ultrasonographic evidence of focal or multifocal intestinal wall thickening and a histological diagnosis of lipogranulomatous lymphangitis. Only dogs that did not undergo surgical resection of the lesions were included. The clinical response to medical treatment, consisting of low-fat or hydrolysed diet along with immunosuppressive agents was assessed; clinicopathological and ultrasonographic abnormalities were re-evaluated over time, with a median follow-up period of 16.5 months.

RESULTS

Four dogs met the inclusion criteria. The main historical complaints were diarrhoea (three of four dogs), vomiting (three of four dogs) and abdominal pain (two of four dogs). Clinicopathological abnormalities comprised hypoproteinaemia, hypoalbuminaemia and mild/moderate increase in C-reactive protein levels (three of four dogs). Abdominal ultrasound revealed focal (two of four dogs) or multifocal (two of four dogs) intestinal wall thickening involving distal jejunum, ileum and ileocolic junction. Histopathology of full thickness intestinal biopsies revealed granulomatous enteritis and lymphangitis with lymphangiectasia. Nutritional and medical treatment allowed complete clinical remission in all four dogs within a month of therapy. Improvement of ultrasound abnormalities was noted in three of the four dogs over a 3- to 12-month period.

CLINICAL SIGNIFICANCE

Intestinal lipogranulomatous lymphangitis is a rare form of canine chronic enteropathy characterised by focal or multifocal intestinal lesions due to the presence of transmural intestinal lipogranulomas. This is the first case series describing successful management of intestinal lipogranulomatous lymphangitis through medical treatment alone.

Comparative Evaluation of Lipid Profile, C-Reactive Protein and Paraoxonase-1 Activity in Dogs with Inflammatory Protein-Losing Enteropathy and Healthy Dogs

Chronic inflammation alters lipoprotein metabolism and causes changes in the serum concentrations of lipids, C-reactive protein (CRP), and paraoxonase-1 activity (PON-1), an enzyme that may act as a local detoxifier, antioxidant, and immunomodulator in the gastrointestinal tract. Scarce information is available in dogs with protein-losing enteropathy secondary to chronic enteropathy (iPLE). The first aim was to describe and compare the lipid profiles, CRP concentrations and PON-1 activities in healthy dogs and in dogs with iPLE. The second aim was to evaluate correlations among clinicopathological, histologic data and lipid profiles in dogs with iPLE. Serum samples from 51 iPLE and 40 healthy dogs were used to study albumin, total protein, CRP, PON-1 activity, cholesterol, triglycerides and lipoprotein classes. Serum concentrations of albumin, total protein, cholesterol, PON-1 activity, and high-density and very-low-density lipoproteins were lower in iPLE dogs compared to healthy controls, while those of triglycerides, low-density lipoproteins, chylomicrons and CRP were higher. Significant correlations between the lipid profile and the existing chronic enteropathy activity index were not found. High-density and low-density lipoproteins correlated with CRP and PON-1. Triglycerides were significantly higher in dogs with both inflammation and lymphangiectasia. The results need to be confirmed in further studies.

In-hospital mortality in dogs with protein-losing enteropathy and associated risk factors

BACKGROUND

Risk factors associated with negative outcomes in dogs with protein-losing enteropathy (PLE) are well documented. However, mortality before hospital discharge and associated risk factors are not well described.

HYPOTHESIS/OBJECTIVES

Report the percentage of dogs with PLE that do not survive to hospital discharge and identify associated risk factors.

ANIMALS

One-hundred and seven dogs presented to a referral hospital and diagnosed with PLE caused by inflammatory enteritis, intestinal lymphangiectasia or both.

METHODS

Retrospective cross-sectional study assessing hospital records. Data on in-hospital mortality and cause were assessed, and presenting signs, treatments prescribed, neutrophil count, lymphocyte count, serum albumin, globulin, and C-reactive protein (CRP) concentrations, and histopathologic findings were compared between survivors and non-survivors.

RESULTS

In-hospital mortality was 21.5% with the most common causes including financial limitations, failure to improve and aspiration pneumonia. Factors associated with mortality during hospitalization included longer duration of hospitalization (P = .04), longer duration of clinical signs (P = .02) and an increase in serum CRP concentration after 1-3 days of in-hospital treatment (P = .02). Higher mortality was identified in Pugs (odds ratio [OR], 4.93; 95% confidence interval [CI], 1.41-17.2; P = .01) and was a result of presumptive aspiration pneumonia in 5/6 of these dogs.

CONCLUSIONS AND CLINICAL IMPORTANCE

Protein-losing enteropathy in dogs has substantial mortality during hospitalization. Monitoring for improvement in CRP concentration after treatment during hospitalization may help predict survival to discharge. Pugs have increased in-hospital mortality because of aspiration pneumonia; measures to prevent, recognize, and promptly treat this complication may improve outcomes in this breed.

Updating the Classification of Chronic Inflammatory Enteropathies in Dogs

Chronic inflammatory enteropathies (CIEs) in dogs are currently classified based on response to sequential treatment trials into food-responsive (FREs); antibiotic-responsive (AREs); immunosuppressant-responsive (IREs); and non-responsive enteropathies (NREs). Recent studies have reported that a proportion of NRE dogs ultimately respond to further dietary trials and are subsequently misclassified. The FRE subset among CIEs is therefore probably underestimated. Moreover, alterations in the gut microbiota composition and function (dysbiosis) have been shown to be involved in CIE pathogenesis in recent research on dogs. Metronidazole and other antibiotics that have been used for decades for dogs with AREs have been demonstrated to result in increased antimicrobial resistance and deleterious effects on the gut microbiota. As a consequence, the clinical approach to CIEs has evolved in recent years toward the gradual abandonment of the use of antibiotics and their replacement by other treatments with the aim of restoring a diverse and functional gut microbiota. We propose here to refine the classification of canine CIEs by replacing the AREs category with a microbiota-related modulation-responsive enteropathies (MrMREs) category.

Collaborative Metabolism: Gut Microbes Play a Key Role in Canine and Feline Bile Acid Metabolism

Bile acids, produced by the liver and secreted into the gastrointestinal tract, are dynamic molecules capable of impacting the overall health of dogs and cats in many contexts. Importantly, the gut microbiota metabolizes host primary bile acids into chemically distinct secondary bile acids. This review explores the emergence of new literature connecting microbial-derived bile acid metabolism to canine and feline health and disease. Moreover, this review highlights multi-omic methodologies for translational research as an area for continued growth in veterinary medicine aimed at accelerating microbiome science and medicine as it pertains to bile acid metabolism in dogs and cats.

Randomized controlled trial of hydrolyzed fish diets in dogs with chronic enteropathy

BACKGROUND

The role of diet in the pathogenesis and treatment of chronic enteropathies (CE) in dogs is unresolved.

OBJECTIVES

To compare the ability of diets composed of hydrolyzed fish, rice starch, and fish oil without (HF) or with prebiotics, turmeric, and high cobalamin (HF+) against a limited ingredient diet containing mixed nonhydrolyzed antigens and oils (control) to resolve clinical signs and maintain serum cobalamin and folate concentrations in dogs with nonprotein losing CE (non-PLE). To determine the ability of hydrolyzed fish diets to support recovery and remission in dogs with PLE.

ANIMALS

Thirty-one client-owned dogs with CE: 23 non-PLE, 8 PLE.

METHODS

Randomized, blinded, controlled trial. Diets were fed for 2 weeks; responders continued for 12 weeks. Nonresponders were crossed over to another diet for 12 weeks. Response was determined by standardized clinical evaluation with long-term follow-up at 26 weeks. Concurrent medications were allowed in PLE.

RESULTS

Nineteen of 23 (83%; 95% confidence interval [CI], 60%-94%) non-PLE CE responded clinically to their initial diet, with no difference between diets (P > .05). Four nonresponders responded to another diet, with sustained remission of 18/18 (100%; 95%CI, 78%-100%) at 26 weeks. Serum cobalamin concentration was increased (P < .05) and maintained by diet. Serum folate concentration decreased posttreatment (P < .05) but was restored by dietary supplementation. Hydrolyzed fish diets supported weight gain, serum albumin concentration, and recovery (P < .05) in dogs with PLE.

CONCLUSIONS AND CLINICAL IMPORTANCE

Changing diet, independent of antigen restriction or supplemental ingredients, induced long-term remission in dogs with non-PLE CE. Serum cobalamin and folate concentrations were maintained by diet. Hydrolyzed fish diets supported clinical recovery and remission in PLE.

Fecal S100A12 concentrations in cats with chronic enteropathies

OBJECTIVES

The aim of this study was to compare fecal S100A12 concentrations in cats diagnosed with chronic enteropathy (CE) with healthy control cats.

METHODS

This was a prospective, cross-sectional study. Forty-nine cats that had gastrointestinal signs for >3 weeks and a complete diagnostic work-up, including bloodwork, abdominal ultrasound and upper and/or lower gastrointestinal endoscopic biopsies, were enrolled into the CE group. Nineteen cats from the CE group were diagnosed with inflammatory bowel disease (IBD) or chronic inflammatory enteropathy (CIE) and 30 with alimentary lymphoma (LSA), based on histopathology results and additional testing with immunohistochemistry or molecular clonality testing with PCR if indicated. Nineteen apparently healthy control cats were included in the study. One fecal sample was collected from each cat and S100A12 concentrations were quantified by an analytically validated in-house ELISA.

RESULTS

Fecal S100A12 concentrations differed between cats with LSA (median 110 ng/g; interquartile range [IQR] 18-548) and control cats (median 4 ng/g; IQR 2-25 [P <0.001]) and between cats with IBD (median 34 ng/g; IQR 15-973) and control cats (P <0.003). S100A12 concentrations in CE cats (median 94 ng/g; IQR 16-548) were statistically significantly higher compared with control cats (P <0.001). The area under the receiver operating characteristic curve (AUROC) to separate healthy cats from CE cats was 0.81 (95% confidence interval [CI] 0.70-0.92) and was statistically significant (P <0.001). The AUROC to separate cats with IBD from cats with LSA was 0.51 (95% CI 0.34-0.68) and was not statistically significant (P = 0.9).

CONCLUSIONS AND RELEVANCE

Fecal S100A12 concentrations at the time of diagnostic investigation were higher in cats with CIE and LSA than in healthy controls but did not differ between cats with LSA and those with CIE/IBD. This study is an initial step toward evaluating a novel non-invasive marker of feline CIE. Further studies are needed to determine the diagnostic utility of fecal S100A12 concentrations in cats with CE, including comparing cats with IBD/CIE and LSA, and to compare them with cats with extra-gastrointestinal disease.

Pathophysiology, Diagnosis, and Management of Canine Intestinal Lymphangiectasia: A Comparative Review

Intestinal lymphangiectasia was first described in the dog over 50 years ago. Despite this, canine IL remains poorly understood and challenging to manage. Intestinal lymphangiectasia is characterized by variable intestinal lymphatic dilation, lymphatic obstruction, and/or lymphangitis, and is a common cause of protein-losing enteropathy in the dog. Breed predispositions are suggestive of a genetic cause, but IL can also occur as a secondary process. Similarly, both primary and secondary IL have been described in humans. Intestinal lymphangiectasia is definitively diagnosed via intestinal histopathology, but other diagnostic results can be suggestive of IL. Advanced imaging techniques are frequently utilized to aid in the diagnosis of IL in humans but have not been thoroughly investigated in the dog. Management strategies differ between humans and dogs. Dietary modification is the mainstay of therapy in humans with additional pharmacological therapies occasionally employed, and immunosuppressives are rarely used due to the lack of a recognized immune pathogenesis. In contrast, corticosteroid and immunosuppressive therapies are more commonly utilized in canine IL. This review aims toward a better understanding of canine IL with an emphasis on recent discoveries, comparative aspects, and necessary future investigations.

Incidence of relapse of inflammatory protein-losing enteropathy in dogs and associated risk factors

BACKGROUND

Dogs with inflammatory protein-losing enteropathy (iPLE) that attain remission may be at risk of subsequent relapse.

OBJECTIVES

To determine the incidence of relapse of iPLE in dogs that have previously attained complete clinical and biochemical remission and identify associated risk factors.

ANIMALS

Seventy-five client-owned dogs diagnosed with iPLE.

METHODS

Medical records of dogs diagnosed with iPLE based on histopathology of intestinal biopsy specimens between March 2010 and March 2020 were retrospectively reviewed. Variables were recorded from the time of investigation at histopathologic diagnosis and subsequent follow-up information was obtained from the records of referring veterinarians.

RESULTS

Twenty-three dogs (31%) achieved sustained remission without documentation of relapse for at least 2 years. Nineteen dogs (25%) achieved remission, but then subsequently relapsed within 2 years of histopathologic diagnosis, and 33 dogs (44%) never achieved remission with disease-associated death occurring a median of 19 (range, 3-114) days after histopathologic diagnosis. Dogs that achieved remission and subsequently relapsed had significantly higher poor dietary compliance, as defined by frequent scavenging or changing from the recommended diet compared to dogs with sustained remission (P = .01).

CONCLUSIONS

Inflammatory PLE is associated with a high rate of relapse in dogs. Ensuring owners adhere to dietary recommendations might help prevent subsequent relapse in dogs with iPLE that attain initial remission.

Home-cooked diets cost more than commercially prepared dry kibble diets for dogs with chronic enteropathies

OBJECTIVE

Nutrition plays a fundamental role in the management of canine chronic enteropathies (CCEs). Dog owners may elect to feed home-cooked diets (HCDs) rather than veterinary commercially prepared diets (CPDs) because of perceived lower costs. There is a paucity of data comparing costs of these options. We hypothesize there will be differences in costs between complete and balanced HCDs and nutritionally comparable CPDs.

SAMPLE

6 Home-cooked diets.

PROCEDURES

Six HCD recipes (2 highly digestible, 2 limited antigen, 2 low-fat) were formulated by 2 board-certified veterinary nutritionists to mimic the nutritional and ingredient profiles of veterinary CPDs for management of CCEs. The cost (in US$ on a per 100 kilocalorie [kcal] basis) of each recipe was determined via collection of ingredient prices from 3 grocery stores combined with supplement prices from online retailers. Prices of CPDs were obtained from a national online retailer. Maintenance energy requirements of 1.6 X (70 X BWkg0.75), where BWkg represents body weight in kilograms, were calculated for 3 dog sizes (5, 20, and 40 kg), and costs of feeding maintenance energy requirements with HCDs versus dry and canned CPDs were compared with a Kruskal-Wallis test and post hoc testing.

RESULTS

The median costs of all dry and canned CPDs and HCDs were $0.29 (range, $0.18 to $0.46), $1.01 (range, $0.77 to $1.20), and $0.55 (range, $0.35 to $1.14), respectively. Feeding complete and balanced HCDs cost more than feeding dry CPDs (P < .001), but not canned CPDs (P > .99).

CLINICAL RELEVANCE

Dry CPDs cost the least for nutritional management of CCEs. There is a wide range of costs for both CPDs and HCDs.

Canine chronic enteropathy—Current state-of-the-art and emerging concepts

Over the last decade, chronic inflammatory enteropathies (CIE) in dogs have received great attention in the basic and clinical research arena. The 2010 ACVIM Consensus Statement, including guidelines for the diagnostic criteria for canine and feline CIE, was an important milestone to a more standardized approach to patients suspected of a CIE diagnosis. Great strides have been made since understanding the pathogenesis and classification of CIE in dogs, and novel diagnostic and treatment options have evolved. New concepts in the microbiome-host-interaction, metabolic pathways, crosstalk within the mucosal immune system, and extension to the gut-brain axis have emerged. Novel diagnostics have been developed, the clinical utility of which remains to be critically evaluated in the next coming years. New directions are also expected to lead to a larger spectrum of treatment options tailored to the individual patient. This review offers insights into emerging concepts and future directions proposed for further CIE research in dogs for the next decade to come.

A Preliminary Study of Modulen IBD Liquid Diet in Hospitalized Dogs with Protein-Losing Enteropathy

Modulen IBD is an enteral liquid diet that can induce remission rates similar to glucocorticoids in children with inflammatory bowel disease. The Modulen IBD liquid diet has not been previously investigated in dogs. Our study aimed to describe the use of the Modulen IBD liquid diet in hospitalized dogs with inflammatory protein-losing enteropathy (PLE), including its tolerance and effects on appetite and gastrointestinal signs, and laboratory parameters during hospitalization. Of the 14 dogs hospitalized for PLE that had an esophagostomy feeding tube placed at the time of endoscopy, 5 were eligible and prospectively enrolled. The Modulen IBD liquid diet was supplemented with whey powder isolate and a multivitamin/mineral blend to ensure the diet was complete and balanced for canine adult maintenance and had a macronutrient profile desirable for PLE. All five dogs tolerated tube feedings with the Modulen IBD liquid diet, allowing an increase of 75 to 100% of the resting energy requirement (RER) by day 3 to 4. The diet was administered without glucocorticoid in all five dogs. All five of these dogs had a resolution of anorexia allowing the voluntary intake of a commercial hydrolyzed protein diet prior to the use of glucocorticoids. Of these five dogs, three (60%) had stable or improved serum albumin concentrations (median % increase: 10.3, range: 0−31.1), four (80%) had improved or normalized serum globulin concentrations (median % increase: 12.9, range: 5.1−66.2) and four (80%) had improved or normalized serum cholesterol concentrations (median % increase: 31.5, range: 4.8−63) 2−3 days after initiating the diet. However, there were no significant differences in these selected biochemical parameters pre- and post-feeding with the diet (p > 0.080). In conclusion, the Modulen IBD liquid diet, fed via an esophagostomy feeding tube was well-tolerated in-hospital and resolved anorexia in all dogs and helped to improve selected biochemical parameters in some dogs. Further studies are needed to assess the long-term effects of feeding this diet on the rate of serum albumin increase and remission in dogs with inflammatory PLE.

2022 Update of the Consensus on the Rational Use of Antithrombotics and Thrombolytics in Veterinary Critical Care (CURATIVE) Domain 1- Defining populations at risk

OBJECTIVES

To expand the number of conditions and interventions explored for their associations with thrombosis in the veterinary literature and to provide the basis for prescribing recommendations.

DESIGN

A population exposure comparison outcome format was used to represent patient, exposure, comparison, and outcome. Population Exposure Comparison Outcome questions were distributed to worksheet authors who performed comprehensive searches, summarized the evidence, and created guideline recommendations that were reviewed by domain chairs. The revised guidelines then underwent the Delphi survey process to reach consensus on the final guidelines. Diseases evaluated in this iteration included heartworm disease (dogs and cats), immune-mediated hemolytic anemia (cats), protein-losing nephropathy (cats), protein-losing enteropathy (dogs and cats), sepsis (cats), hyperadrenocorticism (cats), liver disease (dogs), congenital portosystemic shunts (dogs and cats) and the following interventions: IV catheters (dogs and cats), arterial catheters (dogs and cats), vascular access ports (dogs and cats), extracorporeal circuits (dogs and cats) and transvenous pacemakers (dogs and cats).

RESULTS

Of the diseases evaluated in this iteration, a high risk for thrombosis was defined as heartworm disease or protein-losing enteropathy. Low risk for thrombosis was defined as dogs with liver disease, cats with immune-mediated hemolytic anemia, protein-losing nephropathy, sepsis, or hyperadrenocorticism.

CONCLUSIONS

Associations with thrombosis are outlined for various conditions and interventions and provide the basis for management recommendations. Numerous knowledge gaps were identified that represent opportunities for future studies.

A Descriptive Study on the Extent of Dietary Information Obtained during Consultations at a Veterinary Teaching Hospital

Simple Summary

The majority of dogs with chronic idiopathic gastrointestinal (GI) disease are diet-responsive. We retrospectively evaluated what dietary information was gained when dogs were presented with chronic GI signs to either our Gastroenterology (GE) (n = 243) or Internal Medicine (IM) (n = 239) Service between 10/2017 and 01/2020. Referral documents mentioned the previously fed diet in 53/131 (40%) GE and 14/112 (13%) IM referrals. No dog had received more than one diet trial from the referring veterinarian. Diet trials had been performed in 127/199 (64%) GE and 56/156 (36%) IM dogs prior to presenting to our teaching hospital. The diet fed at the time of consultation could be named by 106/199 (53%) GE and 40/156 (26%) IM dog owners. Data on response to subsequent newly prescribed diets were available from 86 GE dogs and 88 IM dogs. A positive response to diet was noted in 50/86 (58%) GE and 26/88 (30%) IM dogs. A further 23/35 (66%) GE dogs and 12/21 (57%) IM dogs responded positively to a second diet trial, and 4/9 GE dogs (44%) and 6/7 (86%) IM dogs responded positively to a third diet trial. In conclusion, obtainable dietary information was infrequent. Positive response is still possible after initial diet failures. Further studies are now needed to determine if collecting complete dietary information at the time of consultations could lead to an increased percentage of diet-responsive disease.

Abstract

The majority of dogs with chronic idiopathic gastrointestinal (GI) disease respond to diet. So far, no study has assessed how much dietary information is obtained during consultations. We retrospectively evaluated what dietary information was available from dogs presenting to our Gastroenterology (GE), and Internal Medicine (IM) Service between 10/2017 and 01/2020. Data from 243 dogs presenting for first GE consultations were compared to 239 dogs presenting with chronic GI signs for first IM consultations. Referrals comprised 131 (54%) GE dogs and 112 (47%) IM dogs. Referral documents specified the previously fed diet in 53/131 (40%) GE and 14/112 (13%) IM dogs. No dog had received more than one previous diet trial for chronic GI signs. Irrespective of referral status, diet trials had been performed in 127/199 (64%) GE, and 56/156 (36%) IM dogs. The specific diet fed at the time of consultation could only be named by 106/199 (53%) GE and 40/156 (26%) IM dog owners. Data on response to subsequent newly prescribed diets were available from 86 GE dogs and 88 IM dogs. A positive response to diet was noted in 50/86 (58%) GE and 26/88 (30%) IM dogs. A further 23/35 (66%) GE dogs and 12/21 (57%) IM dogs responded positively to a second diet trial, and 4/9 GE dogs (44%) and 6/7 (86%) IM dogs responded positively to a third diet trial. In conclusion, overall dietary information gained from referring veterinarians and owners was often incomplete. More dietary information could be gained during GE consultations compared to IM consultations for chronic GI signs. A positive response to diet can still be seen after two diet failures. Further studies will help to ascertain if the percentage of diet-responsive GI disease increases when more complete dietary information is obtained at the time of consultations.

Dietary management of chronic enteropathy in dogs

Chronic idiopathic enteropathy is a clinical condition defined by the exclusion of infectious, metabolic or neoplastic causes of gastrointestinal signs and is categorised by a response to treatment including management with diet change, immunosuppressant medication or interventions that directly target the microbiome (e.g. antibiotics, faecal transplantation or probiotics). Animals that fail these therapies are categorised as non-responsive or refractory chronic idiopathic enteropathy. This specific categorisation implies that nutritional intervention is only needed for a subset of patients with enteropathy. However, often dogs with chronic idiopathic enteropathy are malnourished, have nutrient malabsorption or have gastrointestinal inflammation that occurs as a result of a breakdown in tolerance to luminal antigens including microorganism or dietary components. Thus, all dogs with chronic idiopathic enteropathy benefit from a nutritional assessment and targeted nutritional intervention. Among dogs presenting for chronic idiopathic enteropathy, the response rate to diet alone is roughly 50% in the referral population giving the impression that the overall response could be even higher especially when more than one nutritional intervention is attempted and strict adherence is maintained. The objectives of this review article are to outline the nutritional approach to a dog with chronic idiopathic enteropathy, including the nutritional assessment, and to highlight areas for nutritional intervention.

Short-Chain and Total Fatty Acid Profile of Faeces or Plasma as Predictors of Food-Responsive Enteropathy in Dogs: A Preliminary Study

Simple Summary

Food-responsive enteropathy is the most common diagnosis given for dogs with chronic enteropathy, and there are no tests that can replace treatment trials. Furthermore, there is a lack of information on the specific nutritional status of these patients regarding the lipid profile that could relate them to the state of health/disease. This study evaluated differences in short-chain fatty acids and the total fatty acid profile of faeces and plasma as possible indicators of food-responsive enteropathy (FRE), as well as its relationship with body condition and the chronic enteropathy activity index. Changes in the long-chain fatty acid of plasma, and short-chain, branched and odd-chain fatty acids of faeces were detected in sick dogs, and high correlations were observed between some of these compounds and the existing calculated indices.

Abstract

The aim of this study was to evaluate differences in short-chain fatty acids (SCFAs) and the total fatty acid profile of faeces or plasma as possible indicators of FRE in comparison with healthy dogs. FRE dogs had a lower concentration (p = 0.026) of plasma α-tocopherol as an indicator of the oxidative status of the animal, and lower C20:5n-3 (p = 0.033), C22:5n-3 (p = 0.005), polyunsaturated fatty acids (PUFA) (p = 0.021) and n-6 (p = 0.041) when compared with the control dogs; furthermore, sick dogs had higher proportions of plasma C20:3n-6 (p = 0.0056). The dogs with FRE showed a decrease in the production of faecal levels of SCFAs, mainly propionic acid (C3) (p = 0.0001) and isovaleric acid (iC5) (p = 0.014). FRE dogs also had a lower proportion of C15:0 (p = 0.0003), C16:1n-9 (p = 0.0095), C16:1n-7 (p = 0.0001), C20:5n-3 (p = 0.0034) and monounsaturated fatty acids (p = 0.0315), and tended to have lower n-3 (p = 0.058) and a reduced desaturase activity index in the stool when compared with the control group. However, the dogs with chronic enteropathy tended to have greater C20:4n-6 (p = 0.065) in their faeces as signs of damage at the intestinal level. The faecal parameters were better predictors than plasma. The highest correlations between faecal odd-chain, medium- or long-chain fatty acids and SCFAs were observed for C15:0 that correlated positively with faecal acetic acid (C2) (r = 0.72, p = 0.004), propionic acid (r = 0.95, p = 0.0001), isobutyric acid (iC4) (r = 0.59, p = 0.027) and isovaleric acid (r = 0.64, p = 0.0136), as well as with total SCFAs (r = 0.61, p = 0.02). Conversely, faecal C20:4n-6 showed a high inverse correlation (r = −0.83, p = 0.0002) with C2 and C3 (r = −0.59, p = 0.027). Canine inflammatory bowel disease (IBD) activity (CIBDAI) index correlated negatively mainly with faecal measurements, such as C3 (r = −0.869, p = 0.0005) and C15:0 (r = −0.825, p = 0.0018), followed by C16:1/C16:0 (r = −0.66, p= 0.0374) and iC5 (r = −0.648, p = 0.0310), which would indicate that these fatty acids could be good non-invasive indicators of the chronic inflammatory status, specifically FRE.

Changes in the coagulation parameters in dogs with protein-losing enteropathy between before and after treatment

Protein-losing enteropathy (PLE) is known to induce hypercoagulability and resultant thromboembolism in dogs. We hypothesized that hypercoagulability would improve if remission was obtained in dogs with PLE after treatment. This study aimed to evaluate the changes in the coagulation parameters after treatment in dogs diagnosed with PLE. As coagulation parameters, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, thrombin-antithrombin complex (TAT), D-dimer, and antithrombin (AT) were measured. In addition to these parameters, rotational thromboelastometry (ROTEM), which evaluates the comprehensive coagulation and fibrinolysis reactions of whole blood, was conducted and the data of clotting time (CT), clot formation time (CFT), α angle (α), maximum clot firmness (MCF) and lysis index at 60 min (LI60) were obtained. Eleven of the 14 dogs diagnosed with PLE were classified as responders to the treatment based on the changes in their plasma albumin (ALB) concentration after treatment. Significant increase in CFT and decrease of α and MCF indicating the resolution of hypercoagulability were found after treatment in responder dogs; however, there was no significant change in the coagulation and fibrinolysis parameters other than those measured by ROTEM. This study demonstrated that the hypercoagulability detected by ROTEM was significantly improved after treatment in dogs with PLE.

The effect of assisted enteral feeding on treatment outcome in dogs with inflammatory protein-losing enteropathy

BACKGROUND

The effect of assisted enteral feeding on treatment outcome in dogs with protein-losing enteropathy (PLE) is unknown.

OBJECTIVES

To determine if dogs with inflammatory PLE that had an enteral feeding tube placed had better outcome vs dogs with inflammatory PLE without a feeding tube.

ANIMALS

Fifty-seven dogs with inflammatory PLE.

METHODS

A retrospective study at a UK referral hospital identified dogs with inflammatory PLE using a standard diagnostic criterion. Positive outcome was defined as survival greater than 6 months or death unrelated to PLE and negative outcome as death related to PLE within 6 months of diagnosis. Several variables were assessed to identify factors for positive outcome using logistic regression.

RESULTS

Thirty-five (61%) and 22 (39%) dogs had a positive and negative outcome at 6 months, respectively. Of the 21 dogs that had a feeding tube placed within 5 days of gastrointestinal biopsy, 16 (76%) had a positive outcome and 5 (24%) had a negative outcome. Dogs treated with dietary treatment alone (P = .002) and dogs with an enteral feeding tube (P = .006) were significantly associated with a positive outcome. When stratified by treatment, assisted enteral feeding was significantly associated with a positive outcome in dogs treated with concurrent immunosuppressive treatment (P = .006), but there was insufficient data to evaluate dogs treated with dietary treatment alone.

CONCLUSIONS AND CLINICAL IMPORTANCE

Assisted enteral feeding in dogs with inflammatory PLE could be associated with improved treatment outcome, especially in those receiving immunosuppressive treatment, and should be considered in the treatment plan of these dogs.

Prospective evaluation of a change in dietary therapy in dogs with steroid-resistant protein-losing enteropathy

OBJECTIVE

To describe the clinical effect of dietary alteration as a sole change to therapy in dogs with steroid-resistant protein-losing enteropathy.

MATERIALS AND METHODS

Prospective study. Eligible enrolled dogs received dietary alteration as sole change to their therapeutic plan. Canine Chronic Enteropathy Clinical Activity Index and serum albumin were monitored for the 3-month study period. Long-term follow-up data were also available for some of the study participants.

RESULTS

Fifteen dogs were eligible for enrollment over the study period. Twelve were enrolled, 10 remained in the study at 30 days, nine completed the 3-month study period. Following dietary alteration, eight of 10 dogs achieved complete remission, one dog achieved partial remission and one dog had no response. Seven of eight dogs achieving complete remission have remained in remission up to 4 years following study. In dogs with complete remission, median Canine Chronic Enteropathy Clinical Activity Index score was 11.5 and 4, and median serum albumin concentration was 15 g/L and 26 g/L at 0 and 14-28 days, respectively.

CLINICAL SIGNIFICANCE

Dogs with protein-losing enteropathy with previous lack of response to a combination of dietary therapies, glucocorticoids and immunosuppressive medications can achieve remission following a dietary change. Improvement is likely to be seen within 14 to 30 days. A change in dietary approach may be an alternative to further immunosuppression or anti-inflammatory strategies in some dogs with difficult to treat protein-losing enteropathy.

Successful management of portal vein thrombosis in a Yorkshire Terrier with protein-losing enteropathy

Background

Portal vein thrombosis (PVT) is a rare presentation in dogs with protein-losing enteropathy (PLE). Rivaroxaban, an oral, selective, direct factor Xa inhibitor, has not been reported to be administrated for canine PVT and the effect is unclear in dogs with PLE.

Case presentation

An 11-year-old Yorkshire Terrier presented with moderate ascites. The dog had severe hypoalbuminemia (1.2 g/dL), and a portal vein thrombus was confirmed on computed tomographic angiography (CTA). On endoscopic examination, it became apparent that the hypoalbuminemia was caused by PLE, which was consequent of lymphatic dilation and lymphoplasmacytic enteritis. Therefore, the dog was initially treated with oral administrations of spironolactone and clopidogrel, with dietary fat restriction. However, a follow-up CTA showed no changes in the ascites, thrombus, and portal vein to aorta (PV/Ao) ratio. Therefore, the dog was additionally prescribed rivaroxaban and low-dose prednisolone for the portal vein thrombus and hypoalbuminemia due to lymphoplasmacytic enteritis, respectively. Following the treatment, the PV/Ao ratio decreased because of a decrease in the thrombus and the ascites disappeared completely with an elevation of albumin concentration (1.9 g/dL).

Conclusions

This case report demonstrated that oral administration of rivaroxaban combined with low-dose glucocorticoid was effective management for PVT in a dog with PLE.

Canine Protein Losing Enteropathies and Systemic Complications

Canine protein-losing enteropathies occur commonly in small animal practice, and their management is often challenging with a long-term survival rate of only about 50%. Recent studies have investigated prognostic factors that may determine outcome in individual cases. In particular, systemic complications such as hypercoagulability, vitamin D3 deficiency, and tryptophan deficiency may play an important role and should be investigated in severely affected cases in order to maximize outcome.

Dietary and Nutritional Approaches to the Management of Chronic Enteropathy in Dogs and Cats

Nutrition can influence those functions of the gastrointestinal tract that can be adversely affected in chronic enteropathy, such as microbiota, mucosal immune system, intestinal permeability, and motility. Diet serves as a possible risk factor in disease pathogenesis and as a target for treatment in chronic enteropathy. Malnutrition is prevalent in people with inflammatory bowel disease and negatively affects outcome. Approximately two-thirds of dogs with protein-losing enteropathy due to chronic enteropathy or lymphangiectasia are underweight. Commercial diets and home-prepared diets have been used successfully in the management of chronic enteropathy. Fat restriction is the main dietary strategy for intestinal lymphangiectasia.

Clinical characteristics of dogs with food-responsive protein-losing enteropathy

Background

In dogs with protein‐losing enteropathy (PLE), data on the clinical characteristics of food‐responsive PLE (FR‐PLE) remain scarce.

Objective

To determine the clinical characteristics of FR‐PLE in dogs responsive to ultralow‐fat diet (ULFD) management.

Animals

Thirty‐three dogs diagnosed with PLE based on standard diagnostic criteria.

Methods

Retrospective review of medical records. Clinical findings were compared between dogs with FR‐PLE (FR‐PLE group) and those with immunosuppressant‐responsive PLE (IR‐PLE) or nonresponsive PLE (NR‐PLE) (IR/NR‐PLE group). The area under the curve (AUC) of a receiver operating characteristic curve was used to evaluate the ability of factors to differentiate the FR‐PLE and IR/NR‐PLE groups. Survival time was compared between the FR‐PLE and IR/NR‐PLE groups.

Results

Twenty‐three dogs responded to ULFD management and were diagnosed with FR‐PLE. The canine chronic enteropathy clinical activity index (CCECAI) was significantly lower in the FR‐PLE group than in the IR/NR‐PLE group (P < .001). The AUC of CCECAI for differentiating the FR‐PLE group was 0.935 (95% confidence interval [CI], 0.845‐1.000) with an optimal cutoff value of 8 (sensitivity, 0.826; specificity, 0.889). Survival times were significantly longer in the FR‐PLE group (median, not reached) than in the IR/NR‐PLE group (median, 432 days; P < .001).

Conclusions and Clinical Importance

Dogs that respond to ULFD management and are diagnosed with FR‐PLE are expected to have a favorable prognosis. Clinical scores, specifically the CCECAI, could be useful for differentiating FR‐PLE from IR‐PLE or NR‐PLE.

Review of cobalamin status and disorders of cobalamin metabolism in dogs

Disorders of cobalamin (vitamin B₁₂) metabolism are increasingly recognized in small animal medicine and have a variety of causes ranging from chronic gastrointestinal disease to hereditary defects in cobalamin metabolism. Measurement of serum cobalamin concentration, often in combination with serum folate concentration, is routinely performed as a diagnostic test in clinical practice. While the detection of hypocobalaminemia has therapeutic implications, interpretation of cobalamin status in dogs can be challenging. The aim of this review is to define hypocobalaminemia and cobalamin deficiency, normocobalaminemia, and hypercobalaminemia in dogs, describe known cobalamin deficiency states, breed predispositions in dogs, discuss the different biomarkers of importance for evaluating cobalamin status in dogs, and discuss the management of dogs with hypocobalaminemia.

Investigation of the efficacy of a dietetic food in the management of chronic enteropathies in dogs

BACKGROUND

Chronic enteropathies (CEs) are a common cause of morbidity in dogs. CEs are diagnosed in dogs with chronic gastrointestinal clinical signs (>3 weeks), inflammatory changes on intestinal biopsies and where no other underlying cause is determined based on a thorough, standardised diagnostic work-up. Based on response to therapy, CEs are subclassified into food-responsive, antibiotic-responsive or steroid-responsive enteropathies. A significant proportion of dogs with a CE are food-responsive; however, there are limited peer-reviewed publications describing the clinical efficacy of the commercially available diets used to treat CE.

METHODS

In this study, the authors evaluated the response of 15 dogs with a CE to a commercially available dietetic food (Hill's Prescription Diet i/d Sensitive Canine Dry). The dogs underwent a standard diagnostic evaluation and did not receive concurrent anthelmintic, antibiotic, glucocorticoid or gastroprotectant therapies. The clinical efficacy of the dietary treatment was assessed by comparing the Canine Inflammatory Bowel Disease Activity Index (CIBDAI) before and a median of 13 days after dietary therapy.

RESULTS

The authors found that the CIBDAI significantly decreased following the introduction of the dietetic food (median CIBDAI score pretreatment 9, post-treatment 2; P<0.0005).

CONCLUSION

This study demonstrates that this dietetic food can be used to successfully manage CE in dogs.

Diagnostic features, treatment, and outcome of dogs with inflammatory protein-losing enteropathy

Background

Protein‐losing enteropathy (PLE) because of chronic inflammatory enteropathy (CIE) in dogs is often treated with a combination of glucocorticoids and second‐line immunosuppressant (SLI). This combined approach might not be necessary in all dogs.

Hypothesis/objectives

To describe diagnostic features and outcomes of dogs with PLE treated with glucocorticoids alone (group P) or with glucocorticoids and SLI (group S).

Animals

Thirty‐one dogs with PLE.

Material and methods

Retrospective analysis of signalment data from diagnostic procedures, treatment, and outcome of dogs with CIE/PLE (from 2015 to 2017), using the hospital's digital case database. Dogs with hypoalbuminemia and CIE were included. Because of a stepwise treatment algorithm, dogs were allocated to group P or S. Time to serum albumin concentrations ≥20 g/L and survival data were collected. Dogs were additionally categorized by their albumin and cobalamin serum concentrations. Multivariate and univariate analysis as well as Pearson's correlation and Kaplan‐Maier survival analysis were performed.

Results

Seventeen dogs were included in group P and 14 in group S. World Small Animal Veterinary Association score of the duodenum was different between groups (P = .05), but none of the other examined data. Median time until serum albumin reached >20 g/L was 13 days. Median survival time after start of treatment was 85 days (range, 13‐463 days) in group P and 166 days (range, 8‐390 days) in group S.

Conclusion and Clinical Importance

No routine diagnostic test was predictive of clinical response, treatment group, or outcome. Glucocorticoid treatment alone can be appropriate in dogs with PLE.

Comparative pathophysiology and management of protein-losing enteropathy

Protein‐losing enteropathy, or PLE, is not a disease but a syndrome that develops in numerous disease states of differing etiologies and often involving the lymphatic system, such as lymphangiectasia and lymphangitis in dogs. The pathophysiology of lymphatic disease is incompletely understood, and the disease is challenging to manage. Understanding of PLE mechanisms requires knowledge of lymphatic system structure and function, which are reviewed here. The mechanisms of enteric protein loss in PLE are identical in dogs and people, irrespective of the underlying cause. In people, PLE is usually associated with primary intestinal lymphangiectasia, suspected to arise from genetic susceptibility, or “idiopathic” lymphatic vascular obstruction. In dogs, PLE is most often a feature of inflammatory bowel disease (IBD), and less frequently intestinal lymphangiectasia, although it is not proven which process is the true driving defect. In cats, PLE is relatively rare. Review of the veterinary literature (1977‐2018) reveals that PLE was life‐ending in 54.2% of dogs compared to published disease‐associated deaths in IBD of <20%, implying that PLE is not merely a continuum of IBD spectrum pathophysiology. In people, diet is the cornerstone of management, whereas dogs are often treated with immunosuppression for causes of PLE including lymphangiectasia, lymphangitis, and crypt disease. Currently, however, there is no scientific, extrapolated, or evidence‐based support for an autoimmune or immune‐mediated mechanism. Moreover, people with PLE have disease‐associated loss of immune function, including lymphopenia, severe CD4+ T‐cell depletion, and negative vaccinal titers. Comparison of PLE in people and dogs is undertaken here, and theories in treatment of PLE are presented.

Evaluation of a structured individualised protocol as a potential cost-effective diagnostic and therapeutic approach to chronic diarrhoea in the dog

Diagnostic investigation and management of chronic diarrhoea in dogs can be cost‐prohibitive to many owners. The objectives of this study were to evaluate evidence‐based, individualised diagnostic and therapeutic protocols for management of dogs with chronic diarrhoea, where financial constraints dictate a budget‐limited approach and where more expensive approaches are deferred until simple affordable protocols are unsuccessful. Twenty‐two client‐owned dogs with chronic (minimum 2 weeks duration) untreated small, large or mixed small/large bowel diarrhoea were enrolled in a budget‐limited step‐wise management protocol (maximum expenditure $300 over 6 weeks), with diagnostic testing and therapeutic trials managed in an individualised and evidence‐based fashion. Success was defined as complete resolution of diarrhoea for a minimum of 1 month. Dogs that failed to respond to a budget‐limited protocol were then enrolled for complete, referral‐level management. Four dogs exited the project early (one death due to caval syndrome, three lost to follow‐up). Thirteen out of the remaining 18 dogs had complete resolution of diarrhoea utilising a budget‐limited approach (success rate 72.2%, confidence intervals 46.5–90.3%) and five dogs were moved on to a referral‐level investigation, with complete resolution of diarrhoea in four out of five. Seventeen out of the 18 dogs therefore responded to a protocol based on a budget‐limited approach followed by extensive investigation only if needed, for an overall success rate of 94.4% (CI 72.7–99.9%). Comprehensive investigation of chronic diarrhoea can be deferred while simple affordable diagnostics and therapeutic trials are conducted in stable canine patients and, often, an extensive management approach will be unnecessary.

Narrative review of therapies for chronic enteropathies in dogs and cats

BACKGROUND

The optimal medical treatment for chronic enteropathy (CE) in dogs and cats is controversial. Sequential treatment using diet, antimicrobials, and immunosuppressive drugs is the most common strategy used by clinicians.

OBJECTIVES

To review the evidence for the effectiveness of dietary, drug, and alternative health interventions for inducing clinical remission in dogs and cats with CE.

ANIMALS

Retrospective study of dogs and cats with a diagnosis of chronic enteropathy.

METHODS

MEDLINE and Centre for Agriculture and Bioscience International (CABI) databases (1950 to March 2017) were searched for randomized controlled trials (RCTs), observational studies, and case series. The primary outcome was induction of clinical remission. All studies were evaluated using the quality of evidence grading guidelines (I-IV), which assign a score defining the strength and quality of the evidence.

RESULTS

Twenty-two studies (11 RCTs in dogs and 2 in cats and 9 cohort studies or case series) met the inclusion criteria for inducing remission of gastrointestinal (GI) signs. Of the 13 RCTs achieving grade I scores, 10 studies (totaling 218 dogs and 65 cats) compared single treatment: diet (n = 3), immunosuppressives (n = 3), antimicrobials (n = 2), anti-inflammatory drugs (n = 1), and probiotics (n = 1). Three case series (grade III) reported clinical remission using an elimination diet fed to 55 cats and use of enrofloxacin to induce remission in dogs with granulomatous colitis (2 studies totaling 16 dogs).

CONCLUSIONS AND CLINICAL IMPORTANCE

The current evidence for treatment of CE is much greater in dogs than in cats. There is sufficient strong evidence to recommend the use of therapeutic GI diets, glucocorticoids, enrofloxacin, or some combination of these in dogs with CE. Therapeutic GI diets and glucocorticoids are most useful in cats with CE.