Perinuclear Antineutrophilic Cytoplasmic Antibody and Response to Treatment in Diarrheic Dogs with Food Responsive Disease or Inflammatory Bowel Disease

Efficacy of an elemental diet in achieving clinical remission in dogs with chronic enteropathy

BACKGROUND

Diet may induce clinical remission in dogs with chronic enteropathy (CE). Elemental diets (EDs), providing protein as amino acids, modulate intestinal immunity and microbiome in rodents and humans.

HYPOTHESIS

Evaluate the impact of an amino acid-based kibble (EL) on CE clinical activity and gastrointestinal (GI)-relevant variables.

ANIMALS

Client-owned dogs (n = 23) with inadequately controlled CE.

METHODS

Prospective, uncontrolled clinical trial. Diagnostic evaluation including upper and lower GI endoscopy was performed before study entry. Canine chronic enteropathy clinical activity index (CCECAI), serum biomarkers, and fecal microbiome were evaluated before and after 2 weeks of EL. Dogs with stable or improved CE remained in the study for another 6 weeks. Pre- and post-EL clinical and microbiological variables were compared statistically using a mixed model.

RESULTS

After 2 weeks of EL, 15 of 22 dogs (68%; 95% confidence interval [CI], 47%-84%) consuming the diet were classified as responders with a median (range) decrease in CCECAI from 6 (3-12) to 2 (0-9; P < .001). Fourteen of 15 responders and 2/7 nonresponders at 2 weeks completed the trial; all 16 were experiencing adequate control at week 8 with a median CCECAI of 2 (0-3). In total, 16/23 dogs (70%; 95% CI, 49%-84%) were responders. Feeding EL caused shifts in fecal bacterial communities, which differed between responders and nonresponders. Serum biomarker concentrations were unchanged throughout the study apart from serum alkaline phosphatase activity.

CONCLUSIONS

Exclusive feeding of EL improved clinical signs in 16 of 23 dogs with uncontrolled CE. Fecal microbiome shifts were associated with response to diet and may represent a mechanism for clinical improvement.

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.

Comparative Study of Classical and Alternative Therapy in Dogs with Allergies

Simple Summary

Acupuncture, phytotherapy, and nutrition are part of traditional Chinese medicine, which has been used for literally hundreds to a few thousand years. These traditional therapeutic methods can effectively diagnose and treat acute and chronic diseases and can be used as a primary or complementary therapy. Used properly, these alternatives are safe and without side effects. Allergy is currently a very common diagnosis affecting dogs. Conventional Western medicine can treat symptoms but often does not identify and resolve the underlying problem. This comparative study was focused on the application of alternative and conventional medicine in allergic conditions in dogs, which were divided into two groups, where the effectiveness of both types of treatment was compared.

Abstract

Allergy is a malfunction of the immune system that causes an inappropriate reaction to normally harmless substances known as allergens, such as food components, pollen, parasites, mites, medication, etc. It is very important to make a correct diagnosis, to identify and to eliminate the offending allergen from the body, and provide control and long-term management to achieve a comfortable life for the animal. In the case of highly intensive pruritus, drugs such as glucocorticoids, antihistamines, and Janus kinase inhibitors are generally administered. Unfortunately, common drugs are not always able to resolve the problem. This comparative clinical-outcomes study focused on the application of alternatives, where a combination of acupuncture with phytotherapy and nutrition was applied. These traditional methods do not affect the body only symptomatologically; instead, they treat the patient as a whole. In this clinical study, the therapeutic effects and partial or complete stabilization of the allergic condition of fourteen dogs divided into two groups were observed, compared, and evaluated.

A prospective multicenter study of the efficacy of a fiber-supplemented dietary intervention in dogs with chronic large bowel diarrhea

Background

Chronic large bowel diarrhea is common in dogs and can have a significant impact on their overall health and well being. We evaluated the safety and efficacy of a therapeutic food with select dietary plant fibers known to contain antioxidant and polyphenol compounds on clinical signs in dogs with chronic diarrhea.

Methods

A prospective clinical study was conducted in 31 adult dogs currently experiencing chronic diarrhea from private veterinary practices in the United States. Enrolled dogs were switched to a complete and balanced dry therapeutic food containing whole grains and polyphenol-containing fiber sources for 56 days. Veterinarians evaluated changes from baseline in overall clinical signs, recurrence of clinical signs, and stool parameters at Days 2, 3, 4, 28, and 56. Dog owners evaluated stool consistency daily and nausea/vomiting, quality of life (QoL), and stooling behaviors at Days 1, 14, 28, and 56. Statistical analysis was performed using a mixed-effects model with Day as a fixed-effect.

Results

Assessments of overall clinical response and stool parameters indicated that diarrhea improved significantly within 1 day of initiating the therapeutic food. Veterinarians reported that 68% of dogs had complete resolution of their clinical signs by Day 56 and the remaining 32% experienced improvement (P < 0.05), with no cases of recurrence. Veterinarians also reported improvement in stool consistency (P < 0.001) and reductions of blood and mucus in stool (P < 0.001). Significant improvements in nausea/vomiting, stooling behaviors, and quality of life (QoL) were reported by dog owners after 28 days and were sustained through day 56 (P < 0.05). The therapeutic food was safe and well tolerated.

Conclusions

In dogs with chronic large bowel diarrhea, the therapeutic food rapidly improved stool consistency, resolved clinical signs, and improved stooling behaviors and QoL. Therapeutic foods supplemented with fiber sources rich in antioxidant and anti-inflammatory compounds contribute to rapid resolution of chronic diarrhea without recurrence and may contribute to long term health.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03302-8.

Preliminary evaluation of serum zonulin in canine chronic enteropathies

OBJECTIVES

In humans, serum zonulin, a biomarker of intestinal permeability, correlates with underlying enteropathies and has potential application as a therapeutic target. The aim of this study was to evaluate serum zonulin as a biomarker for canine chronic enteropathy.

MATERIALS AND METHODS

Prospective enrolment of twenty-one client-owned dogs with at least 1 of the following gastrointestinal (GI) signs for at least 3 weeks duration: anorexia, hyporexia, dysrexia, vomiting, weight loss or diarrhea. 21 control dogs, age and breed matched, were also enrolled. Dogs with gastrointestinal signs were diagnosed with chronic enteropathy based on a complete blood count, serum chemistry, specific canine pancreatic lipase, cobalamin, resting cortisol, abdominal ultrasound and gastrointestinal endoscopy with histopathology. Enrolled control dogs had an unremarkable physical examination, complete blood count, serum chemistry and no clinical signs of gastrointestinal disease. Dogs were ineligible if antibiotics or immunosuppressive medications were administered within 1 month of enrolment. Blood samples were analysed using a commercial canine serum zonulin quantitative ELISA.

RESULTS

Dogs with chronic enteropathies had median serum zonulin values of 0.28 ng/mL (interquartile range: 0.04-2.59), while control dogs of 0.27 ng/mL (0.05-3.67). There was no significant difference in canine serum zonulin levels between these populations. The estimated difference in the median concentrations was -0.01 ng/mL (95% CI: -0.23 to 0.89).

CLINICAL SIGNIFICANCE

In this study, using a commercial canine zonulin ELISA, serum zonulin levels did not differentiate between dogs with chronic enteropathies and control dogs.

Enterocytes in Food Hypersensitivity Reactions

Simple Summary

Hypersensitivity to food, affecting both animals and humans, is increasing. Until a decade ago, it was thought that enterocytes, the most abundant constituent of the intestinal surface mucosa layer, served only to absorb digested food and prevent foreign and non-digested substances from passing below the intestinal layer. Growing evidence supports the involvement of enterocytes in immunological responses. Here, we present a comprehensive review of the new roles of enterocytes in food hypersensitivity conducted in animal models in order to better understand complicated immune pathological conditions. In addition, resources for further work in this area are suggested, along with a literature overview of the specific roles of enterocytes in maintaining oral tolerance. Lastly, it will be beneficial to investigate the various animal models involved in food hypersensitivity to reach the needed momentum necessary for the complete and profound understanding of the mechanisms of the ever-growing number of food allergies in animal and human populations.

Abstract

Food hypersensitivity reactions are adverse reactions to harmless dietary substances, whose causes are hidden within derangements of the complex immune machinery of humans and mammals. Until recently, enterocytes were considered as solely absorptive cells providing a physical barrier for unwanted lumen constituents. This review focuses on the enterocytes, which are the hub for innate and adaptive immune reactions. Furthermore, the ambiguous nature of enterocytes is also reflected in the fact that enterocytes can be considered as antigen-presenting cells since they constitutively express major histocompatibility complex (MHC) class II molecules. Taken together, it becomes clear that enterocytes have an immense role in maintaining oral tolerance to foreign antigens. In general, the immune system and its mechanisms underlying food hypersensitivity are still unknown and the involvement of components belonging to other anatomical systems, such as enterocytes, in these mechanisms make their elucidation even more difficult. The findings from studies with animal models provide us with valuable information about allergic mechanisms in the animal world, while on the other hand, these models are used to extrapolate results to the pathological conditions occurring in humans. There is a constant need for studies that deal with this topic and can overcome the glitches related to ethics in working with animals.

Circulating Endocannabinoids as Diagnostic Markers of Canine Chronic Enteropathies: A Pilot Study

Chronic enteropathies (CEs) in dogs, according to the treatment response to consecutive trials, are classified as food-responsive (FRE), antibiotic-responsive (ARE), and immunosuppressive-responsive (IRE) enteropathy. In addition to this classification, dogs with loss of protein across the gut are grouped as protein-losing enteropathy (PLE). At present, the diagnosis of CEs is time-consuming, costly and sometimes invasive, also because non-invasive biomarkers with high sensitivity and specificity are not yet available. Therefore, this study aimed at assessing the levels of circulating endocannabinoids in plasma as potential diagnostic markers of canine CEs. Thirty-three dogs with primary chronic gastrointestinal signs presented to Veterinary Teaching Hospitals of Teramo and Bologna (Italy) were prospectively enrolled in the study, and 30 healthy dogs were included as a control group. Plasma levels of N-arachidonoylethanolamine (AEA), 2-arachidonoylglycerol (2-AG), N-palmitoylethanolamine (PEA), and N-oleoylethanolamine (OEA) were measured at the time of the first visit in dogs with different CEs, as well as in healthy subjects. Plasma levels of 2-AG (p = 0.001) and PEA (p = 0.008) were increased in canine CEs compared to healthy dogs. In particular, PEA levels were increased in the FRE group compared to healthy dogs (p = 0.04), while 2-AG was higher in IRE than in healthy dogs (p = 0.0001). Dogs affected by FRE also showed decreased 2-AG (p = 0.0001) and increased OEA levels (p = 0.0018) compared to IRE dogs. Moreover, dogs with PLE showed increased 2-AG (p = 0.033) and decreased AEA (p = 0.035), OEA (p = 0.016) and PEA (p = 0.023) levels, when compared to dogs affected by CEs without loss of proteins. The areas under ROC curves for circulating 2-AG (0.91; 95% confidence interval [CI], 0.79–1.03) and OEA (0.81; 95% CI, 0.65–0.97) showed a good accuracy in distinguishing the different forms of CEs under study (FRE, ARE and IRE), at the time of the first visit. The present study demonstrated that endocannabinoid signaling is altered in canine CEs, and that CE subtypes showed distinct profiles of 2-AG, PEA and OEA plasma levels, suggesting that these circulating bioactive lipids might have the potential to become candidate biomarkers for canine CEs.

From Bench Top to Clinics: How New Tests Can Be Helpful in Diagnosis and Management of Dogs with Chronic Enteropathies

In this article, we review different tests that have been researched in dogs with chronic enteropathy. The usefulness of these tests either to assess etiology, to differentiate between treatment response, or to monitor treatment response is discussed. The tests are divided in those that are commercially available and those that hold promises for further development.

[Patient owner surveys in small animal medicine - importance, benefits and pitfalls in planning, execution and analysis]

OBJECTIVE

In the present study, the benefits and difficulties of planning and conducting patient surveys in veterinary medicine were examined using 2 examples. One focus was placed on the comparison of the subjective assessment and perception of patient owners with regard to long-term investigation of disease progression.

STUDY POPULATION

An owner survey was conducted in dogs with chronic enteropathy (CE) and degenerative mitral valve disease (DMVD). In both surveys, the case system of the Clinic for Small Animals of the University of Veterinary Medicine Hannover was used to identify suitable cases based on appropriate diagnoses. Owners were contacted and invited to complete (digitally or postally) a multipart questionnaire on their dogs. The results of the survey were evaluated regarding their agreement with literature data. Based on the results of this evaluation, the study design, reliability of owner perception and the benefit of the survey were examined critically.

RESULTS

The search in the clinic's case system provided 125 suitable cases for CE and 145 for DMVD. A total of 81 (CE, response rate 64.8 %) and 72 (DMVD, response rate 49,7 %) owners answered the questionnaire. The owners provided considerably different information concerning the diagnostic examination of their animals. While the statements on the course and forms of disease in CE corresponded to the information from the literature, this was not always the case with DMVD.

CONCLUSION AND CLINICAL RELEVANCE

Patient owner surveys may provide important information about disease progression from the owner's perspective. This is particularly valuable in chronic diseases, the management of which requires good owner compliance. An identical approach to patient selection may lead to results differing in their informative value depending on the disease.

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.

The role of Campylobacter spp. in chronic enteropathy in dogs

The aim of the study was to identifyCampylobacterspecies in a group of patients with chronic gastrointestinal problems and to investigate the relationship between the presence ofCampylobacterspp. in stool samples and as well as the severity of chronic enteropathy. Twenty-six dogs with chronic gastrointestinal problems were included in the prospective study. Each research subject had their stomach, duodenum, ileum, and colon examined endoscopically. A histopathological examination of the obtained biopsy samples was then performed, excluding other potential diseases. Stool samples were collected and then examined for the presence ofCampylobacterspp. To evaluate the relationship betweenCampylobacterspp. occurrence and the intensity of chronic enteropathy, patients were divided into two groups; animals in the first group presented with no to mild inflammation whereas research subjects in the second group suffered from moderate to severe inflammation. Subsequently, the patients were divided based on positive or negative test results forCampylobacterspp. cultures. No significant relationship between the presence ofCampylobacterspp. in stool samples and chronic enteropathy was found. In contrast to other previously published papers, our study showed a lower occurrence ofCampylobacter upsaliensis.

Treatment response and long term follow up in nineteen dogs diagnosed with chronic enteropathy in Australia

Chronic enteropathy (CE) in dogs is common worldwide, but little data is available from Australia. The aim of this study was to describe treatment response and long-term outcome in a cohort of dogs with CE. Dogs were prospectively enrolled at Murdoch University and the University of Melbourne. After diagnostic investigation to rule out diseases other than CE, dogs underwent sequential therapeutic trials until achieving a clinical response (diet then antibiotics, and finally immunosuppressants). Success was defined as 75% reduction of clinical severity for a minimum of five weeks. A total of 21 dogs were enrolled, and 19 completed the study. One dog was euthanised for lack of response to treatment and one excluded for lack of owner compliance. Most dogs responded to diet (n = 10), followed by antibiotics (n = 7) and immunosuppressants (n = 2). Long-term remission (median 21.1 months, [3.0-44.7]) was achieved in eight out of ten dietary responders without additional treatment. In contrast, only two dogs with antibiotic response remained in long-term remission, of which one needed on-going antibiotic treatment. Longer term remission was achieved in the two dogs treated with immunosuppressants with on-going low dose therapy. This study concludes that most dogs referred for CE in Australia respond to dietary treatment (even after previous dietary interventions), and remission is long-term compared to dogs treated with an antibiotic. Furthermore, the need for long-term antibiotics in some dogs to maintain response may lead to antibiotic resistance. This study supports adequate dietary trials for CE in dogs, and a need for alternative second-line treatments.

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.

Mucosal immunity and gut microbiota in dogs with chronic enteropathy

Chronic enteropathy (CE) in dogs is a chronic and relapsing immunopathology, of unknown etiology, that usually manifests with a plethora of clinical signs reflecting the underlying heterogeneity in its pathogenesis. Alterations of the mucosal immune responses and the gut microbiota composition are thought to play an essential role in CE. Similar to humans, it is hypothesized that the breakdown in mucosal tolerance leads to aberrant and pathological immune responses toward the gut microbiota, that in turn, may contribute to the severity of disease, at least for certain CE subsets. Therefore, in this review, we discuss some of the most relevant and recent insights microbiological and immunological aspects characterizing CE in dogs.

Critically appraised topic on adverse food reactions of companion animals (6): prevalence of noncutaneous manifestations of adverse food reactions in dogs and cats

BACKGROUND

Many reports describe the cutaneous signs of adverse food reactions (AFR) in the dog and cat. However, various non-cutaneous clinical signs are less well described. Our objective was to systematically evaluate these non-cutaneous signs of AFR in small animals.

RESULTS

We searched two databases (MEDLINE and Web of Science) for pertinent references on non-cutaneous signs of adverse food reactions. Among 117 and 764 articles found in the MEDLINE and Web of Science databases, respectively, we selected 47 articles that reported data related to non-cutaneous clinical signs of AFR. Gastrointestinal signs, symmetrical lupoid onychitis, conjunctivitis, sneezing, and anaphylaxis were reported to be associated with AFR in dogs and gastrointestinal and respiratory signs, conjunctivitis, and hyperactive behaviour in cats. In Border terriers with paroxysmal gluten-sensitive dyskinesia, an underlying AFR should be considered. Of these clinical signs diarrhoea and frequent defecation were most frequently reported to be diet-responsive in dogs; in the cat, these were vomiting and diarrhoea.

CONCLUSIONS

An elimination diet should be considered early in the work-up of dogs and cats with chronic vomiting and diarrhoea. Other non-cutaneous signs occur less commonly because of AFRs.

Detection of anti-neutrophil cytoplasmic antibodies in dogs with immune-mediated inflammatory diseases

Anti-neutrophil cytoplasmic antibody (ANCA) is a type of autoantibody against neutrophil cytoplasm. In veterinary medicine, few studies have reported the detection of ANCA in dogs, and most of these studies were performed in dogs with inflammatory bowel disease (IBD). The aim of this study was to evaluate whether ANCA is detected in dogs with immune-mediated inflammatory diseases (IMIDs) other than IBD. Serum samples were collected before treatment initiation from 40 client-owned dogs with various diseases and 22 healthy beagle dogs; the dogs were classified into two groups: IMID group (n = 16) and control group (n = 46). ANCA was detected using the indirect fluorescent antibody test. Of the 16 dogs in the IMID group, 13 (81.3%) tested positive for ANCA. In contrast, of the 46 dogs in the control group, 13 (28.03%) tested positive for ANCA. Moreover, a significant association between ANCA positivity and IMIDs was identified in the IMID group than in the control group (P = 0.0003). In the control group, however, dogs with bacterial infection showed a relatively high rate of ANCA positivity. Therefore, ANCA positivity was observed in dogs with both IMIDs and bacterial infection. This suggested that ANCA positivity is associated with diseases accompanied by neutrophil activation and infiltration.

Clinical utility of currently available biomarkers in inflammatory enteropathies of dogs

Chronic inflammatory enteropathies (CIE) in dogs are a group of disorders that are characterized by chronic persistent or recurrent signs of gastrointestinal disease and histologic evidence of mucosal inflammation. These CIEs are classified as either food-responsive, antibiotic-responsive, or immunosuppressant-responsive enteropathy. Patients not clinically responding to immunomodulatory treatment are grouped as nonresponsive enteropathy and dogs with intestinal protein loss as protein-losing enteropathy. Disease-independent clinical scoring systems were established in dogs for assessment of clinical disease severity and patient monitoring during treatment. Histopathologic and routine clinicopathologic findings are usually not able to distinguish the subgroups of CIE. Treatment trials are often lengthy and further diagnostic tests are usually at least minimally invasive. Biomarkers that can aid in defining the presence of disease, site of origin, severity of the disease process, response to treatment, or a combination of these would be clinically useful in dogs with CIE. This article summarizes the following biomarkers that have been evaluated in dogs with CIE during the last decade, and critically evaluates their potential clinical utility in dogs with CIE: functional biomarkers (cobalamin, methylmalonic acid, folate, α1 -proteinase inhibitor, immunoglobulin A), biochemical biomarkers (C-reactive protein, perinuclear anti-neutrophilic cytoplasmic antibodies, 3-bromotyrosine, N-methylhistamine, calprotectin, S100A12, soluble receptor of advanced glycation end products, cytokines and chemokines, alkaline phosphatase), microbiomic biomarkers (microbiome changes, dysbiosis index), metabolomic biomarkers (serum metabolome), genetic biomarkers (genomic markers, gene expression changes), and cellular biomarkers (regulatory T cells). In addition, important performance criteria of diagnostic tests are briefly reviewed.

Genome-wide association studies of inflammatory bowel disease in German shepherd dogs

Canine Inflammatory Bowel Disease (IBD) is considered a multifactorial disease caused by complex interactions between the intestinal immune system, intestinal microbiota and environmental factors in genetically susceptible individuals. Although IBD can affect any breed, German shepherd dogs (GSD) in the UK are at increased risk of developing the disease. Based on previous evidence, the aim of the present study was to identify single nucleotide polymorphisms (SNPs), which may confer genetic susceptibility or resistance to IBD using a genome-wide association study (GWAS). Genomic DNA was extracted from EDTA blood or saliva samples of 96 cases and 98 controls. Genotyping of cases and controls was performed on the Canine Illumina HD SNP array and data generated was analyzed using PLINK. Several SNPs and regions on chromosomes 7,9,11 and 13 were detected to be associated with IBD using different SNP-by-SNP association methods and FST windows approach. Searching one Mb up-and down-stream of the most significant SNPs, as identified by single SNP analysis as well as 200Kb before and after the start and the end position of the associated regions identified by FST windows approach, we identified 63 genes. Using a combination of pathways analysis and a list of genes that have been reported to be involved in human IBD, we identified 16 candidate genes potentially associated with IBD in GSD.

Serologic and fecal markers to predict response to induction therapy in dogs with idiopathic inflammatory bowel disease

Background

Little information is available of markers that assess the disease course in dogs with idiopathic inflammatory bowel disease (IBD).

Objectives

Evaluate relationship between disease severity and serum and fecal biomarkers in dogs with idiopathic IBD before and after treatment.

Animals

Sixteen dogs with idioptahic IBD and 13 healthy dogs.

Methods

Prospective case control study. Canine IBD activity index (CIBDAI) clinical score, serum concentrations of C‐reactive protein (CRP), perinuclear antineutrophil cytoplasmic antibodies (pANCA), and serum and fecal canine calprotectin (cCP) were measured before and after 21 days of treatment.

Results

Serum CRP (median 3.5 mg/L; range: 0.1‐52.4 mg/L), fecal cCP (median 92.3 μg/g; range: 0.03‐637.5 μg/g), and CIBDAI scores significantly increased in dogs with IBD before treatment compared with serum CRP (median 0.2 mg/L; range: 0.1‐11.8 mg/L; P < .001), fecal cCP (median 0.67 μg/g; range: 0.03‐27.9 μg/g; P < .001) and CIBDAI (P < .001) after treatment. No significant associations between CIBDAI scores and before or after treatment serum biomarkers. There was a significant association between fecal cCP and CIBDAI scores before treatment (rho = 0.60, P = .01). CRP and fecal cCP significantly decreased after treatment (median 3.5 mg/L v. 0.2 mg/L; P < .001 and 92.3 μg/g v. 0.67 μg/g; P = .001, respectively).

Conclusions and Clinical Importance

Our data indicate that measurement of fecal cCP concentration is a useful biomarker for noninvasive evaluation of intestinal inflammation. Dogs with severe signs of GI disease more often have abnormal markers than dogs having less severe disease.

Comparison of efficacy of oral and parenteral cobalamin supplementation in normalising low cobalamin concentrations in dogs: A randomised controlled study

The aim of this study was to compare the efficacies of parenteral and oral cobalamin supplementation protocols in dogs with chronic enteropathies and low cobalamin concentrations. It was hypothesised that both treatments would increase serum cobalamin concentrations significantly. Fifty-three dogs with chronic enteropathies and serum cobalamin concentrations<285ng/L (reference interval 244-959ng/L) were enrolled. Dogs were randomised to treatment with either daily oral cobalamin tablets (0.25-1.0mg cyanocobalamin daily according to body weight) or parenteral cobalamin (0.4-1.2mg hydroxycobalamin according to body weight). Serum cobalamin concentrations were analysed 28±5days and 90±15days after initiation of supplementation. After 28 days, all dogs had serum cobalamin concentrations within the reference interval or above. In the parenteral group (n=26), median (range) cobalamin concentrations were 228 (150-285) ng/L at inclusion, 2107 (725-10,009) ng/L after 28days and 877 (188-1267) ng/L after 90 days. In the oral group (n=27), median (range) serum cobalamin concentrations were 245 (150-285) ng/L at inclusion, 975 (564-2385) ng/L after 28days and 1244 (738-4999) ng/L after 90 days. In both groups, there were significant differences in serum cobalamin concentrations between baseline and 28 days, and between 28days and 90days (P<0.001). In conclusion, both parenteral and oral cobalamin supplementation effectively increase serum cobalamin concentrations in dogs with chronic enteropathies and low cobalamin concentrations.

Use of a Granulocyte Immunofluorescence Assay Designed for Humans for Detection of Antineutrophil Cytoplasmic Antibodies in Dogs with Chronic Enteropathies

BACKGROUND

Perinuclear antineutrophil cytoplasmic antibodies (pANCA) previously have been shown to be serum markers in dogs with chronic enteropathies, with dogs that have food-responsive disease (FRD) having higher frequencies of seropositivity than dogs with steroid-responsive disease (SRD). The indirect immunofluorescence (IIF) assay used in previous publications is time-consuming to perform, with low interobserver agreement.

HYPOTHESIS/OBJECTIVES

We hypothesized that a commercially available granulocyte IIF assay designed for humans could be used to detect perinuclear antineutrophil cytoplasmic antibodies in dogs.

ANIMALS

Forty-four dogs with FRD, 20 dogs with SRD, 20 control dogs, and 38 soft-coated wheaten terrier (SCWT) or SCWT-cross dogs.

METHODS

A granulocyte assay designed for humans was used to detect pANCA, cANCA, and antinuclear antibodies (ANA), as well as antibodies against proteinase-3 protein (PR-3) and myeloperoxidase protein (MPO) in archived serum samples.

RESULTS

Sensitivity of the granulocyte assay to predict FRD in dogs was 0.61 (95% confidence interval (CI), 0.45, 0.75), and specificity was 1.00 (95% CI, 0.91, 1.00). A significant association was identified between positive pANCA or cANCA result and diagnosis of FRD (P < 0.0001). Agreement between the two assays to detect ANCA in the same serum samples from SCWT with protein-losing enteropathy/protein-losing nephropathy (PLE/PLN) was substantial (kappa, 0.77; 95% CI, 0.53, 1.00). Eight ANCA-positive cases were positive for MPO or PR-3 antibodies.

CONCLUSIONS AND CLINICAL IMPORTANCE

The granulocyte immunofluorescence assay used in our pilot study was easy and quick to perform. Agreement with the previously published method was good.

Expression of serotonin, chromogranin-A, serotonin receptor-2B, tryptophan hydroxylase-1, and serotonin reuptake transporter in the intestine of dogs with chronic enteropathy

Serotonin regulates many intestinal motor and sensory functions. Altered serotonergic metabolism has been described in human gastrointestinal diseases. The objective of our study was to compare expression of several components of the serotonergic system [serotonin (5-HT), serotonin reuptake transporter protein (SERT), tryptophan hydroxylase-1 (TPH-1), 5-HT receptor2B (5-HT2B)] and the enterochromaffin cell marker chromogranin-A (CgA) in the intestinal mucosa between dogs with chronic enteropathy and healthy controls. Serotonin and CgA expression were determined by immunohistochemistry using banked and prospectively obtained, paraffin-embedded canine gastrointestinal biopsies (n = 11), and compared to a control group of canine small intestinal sections (n = 10). Expression of SERT, TPH-1, and 5-HT2B were determined via real-time reverse transcription (qRT)-PCR using prospectively collected endoscopic duodenal biopsies (n = 10) and compared to an additional control group of control duodenal biopsies (n = 8, control group 2) showing no evidence of intestinal inflammation. Dogs with chronic enteropathies showed strong staining for both 5-HT and CgA. Mean positive cells per high power field (HPF) were significantly increased for both compounds in dogs with chronic enteropathies (p < 0.001 for 5-HT; p < 0.05 for CgA). The number of 5-HT-positive and CgA-positive cells/HPF showed significant correlation in the entire group of dogs, including both diseased and healthy individuals (Pearson r(2) = 0.2433, p = 0.016). No significant differences were observed for SERT, TPH-1, or 5-HT2B expression; however, dogs with chronic enteropathy showed greater variability in expression of TPH-1 and 5-HT2B We conclude that components of the neuroendocrine system show altered expression in the intestinal mucosa of dogs with chronic enteropathy. These changes may contribute to nociception and clinical signs in these patients.

Endoscopic assessment of the duodenum in dogs with inflammatory bowel disease

BACKGROUND

Endoscopy is performed for direct inspection of the mucosa and acquisition of biopsies in dogs with inflammatory bowel disease (IBD).

AIM

To evaluate the interobserver agreement in the endoscopic assessment of duodenal mucosa in dogs with IBD.

METHODS

Thirty-five archived endoscopic images of grossly normal (n = 6) and inflamed (n = 29) duodenal mucosa were displayed to 3 expert and 5 trainee endoscopists. Each image was assessed independently by endoscopists for mucosal abnormalities using established indices (of hyperemia, granularity, friability, lymphatic dilatation, and erosions) or interpreted as normal mucosa (trial 1). A repeated trial (trial 2) was performed with the same images presented in random order 1 month later, and accompanied by a visual template.

RESULTS

There was slight interobserver agreement in initial mucosal assessment for expert and trainee endoscopists in trial 1 (kappa ≤ 0.02, P > .05). Interobserver agreement improved in trial 2 for both expert and trainee endoscopists (kappa = 0.2, P > .05) for experts and (P < .05) for trainees. There was a significant (P < .01) improvement in trainee endoscopy scores of lesions from trial 1 to trial 2. Regression analysis showed a significant (P < .01) difference between expert versus trainee endoscopy scores in trial 1. Repeat lesion assessment aided by use of a visual template (trial 2) improved the overall scores of trainee endoscopists to near that of expert endoscopists (P = .06).

CONCLUSIONS AND CLINICAL IMPORTANCE

Interobserver agreement of IBD mucosal appearance from endoscopic findings benefitted from operator experience.

Erosive rhinitis resembling granulomatosis with polyangiitis (Wegener's granulomatosis) in an Anatolian shepherd dog

Granulomatosis with polyangiitis (Wegener's granulomatosis) is one of the idiopathic immune-mediated small-vessel vasculitides described in humans which are characterised by the presence of circulating antineutrophil cytoplasmic antibodies. It most commonly involves capillaries, venules and arterioles of the ear, nose and throat, lungs and glomeruli. A case of destructive haemopurulent rhinitis associated with relapsing periods of pyrexia, lethargy and stiffness as well as generalised pulmonary infiltrates in a young Anatolian shepherd dog is presented that closely resembles granulomatosis with polyangiitis (GPA) as reported in humans. Perinuclear antineutrophil cytoplasmic antibodies (pANCA) were detected in the dog's serum. Signs resolved promptly and completely once immunosuppressive doses of prednisone were administered, and have not recurred. This is the first report on the use of pANCA to investigate rhinitis in dogs. It is also, to the authors’ knowledge, the first description of a relapsing haemopurulent lytic rhinitis in this species. The concurrent manifestations of erosive haemopurulent rhinitis, ground-glass opacities on pulmonary computed tomography, pyrexia and listlessness resemble GPA as described in humans.

A prospective, randomized, blinded, placebo-controlled pilot study on the effect of Enterococcus faecium on clinical activity and intestinal gene expression in canine food-responsive chronic enteropathy

Background

Canine chronic enteropathies (CE) are believed to be caused by an aberrant immune response towards the intestinal microbiome. Administration of probiotics can alleviate colitis in people. In vitro effects of the probiotic Enterococcus faecium NCIMB 10415 E1707 (EF) previously have been evaluated using canine cells (e.g., whole blood, intestinal biopsies), but data on in vivo efficacy are lacking.

Hypothesis/Objectives

Administration of EF to dogs with food‐responsive CE will improve clinical outcome and decrease the intestinal inflammatory profile.

Animals

Dogs diagnosed with CE were prospectively recruited to receive a hydrolyzed elimination diet plus either a synbiotic product containing EF or placebo for 6 weeks. Both veterinary staff and owners were blinded to the treatment.

Methods

Clinical severity index (CCECAI), clinicopathological data and gene expression using intestinal biopsies (TLR2/4/5/9, IL‐17A, IL‐22, IL‐23p19, RORC, IL‐2, IL‐12p35, TNFα, IL‐4, IFNy, IL‐10, TGFβ, IL‐1β, IL‐18, NLRP3, casp‐1, TFF1, TFF3 and PPARy) before and after 6 weeks of treatment were analyzed using linear mixed modeling.

Results

Of the 45 cases recruited, 12 finished the clinical trial. Seven received the synbiotic and 5 the placebo product. There was no difference between groups or treatments regarding clinical efficacy, histology scores or expression of any of the investigated genes.

Conclusions and clinical importance

Standard dietary treatment induced rapid clinical response in all cases. Because the study was underpowered, it was not possible to determine whether or not EF had an additional effect within the time period of 6 weeks.

Urinary and faecal N-methylhistamine concentrations do not serve as markers for mast cell activation or clinical disease activity in dogs with chronic enteropathies

Background

This study sought to correlate faecal and urinary N-methylhistamine (NMH) concentrations with resting versus degranulated duodenal mast cell numbers in dogs with chronic enteropathies (CE), and investigate correlations between intestinal mast cell activation and clinical severity of disease as assessed by canine chronic enteropathy clinical activity index (CCECAI), and between urinary and faecal NMH concentrations, mast cell numbers, and histopathological scores. Twenty-eight dogs with CE were included. Duodenal biopsies were stained with haematoxylin and eosin (H&E), toluidine blue, and by immunohistochemical labelling for tryptase. Duodenal biopsies were assigned a histopathological severity score, and duodenal mast cell numbers were counted in five high-power fields after metachromatic and immunohistochemical staining. Faecal and urinary NMH concentrations were measured by gas chromatography–mass spectrometry.

Results

There was no correlation between the CCECAI and faecal or urinary NMH concentrations, mast cell numbers, or histopathological score – or between faecal or urinary NMH concentration and mast cell numbers. Post hoc analysis revealed a statistically significant difference in toluidine blue positive mast cells between two treatment groups (exclusion diet with/without metronidazole versus immunosuppression (IS)), with higher numbers among dogs not requiring IS.

Conclusion

Faecal and urinary NMH concentrations and duodenal mast cell numbers were not useful indicators of severity of disease as assessed by the CCECAI or histological evaluation. The number of duodenal mast cells was higher in dogs that did not need IS, i.e. in dogs responding to an exclusion diet (with/without metronidazole), than in dogs requiring IS. Further studies comparing the role of mast cells in dogs with different forms of CE are needed.

Biomarkers in canine inflammatory bowel disease diagnostics

Canine inflammatory bowel disease (IBD) is a heterogeneous group of chronic gastrointestinal disorders. The etiology, similar to human IBD, remains unknown. Canine IBD is diagnosed by exclusion, which is a long, time and money-consuming process due to the need of elimination of other diseases presenting with similar symptoms. Therefore, a search for a specific and sensitive marker is needed to overcome these difficulties. The article is divided into 3 sections presenting up-to-date information about laboratory markers, immunohistochemical markers and changes in the neurochemical coding of the enteric nervous system, concentrating on their usefulness and future applications. Data concerning laboratory and immunohistochemical markers is based mainly on canine IBD, while the neuroimmunohistochemistry section presents knowledge from human IBD due to the lack of such studies in veterinary medicine.

Diagnosis of small intestinal disorders in dogs and cats

Laboratory tests are an important part of the workup of small intestinal diseases in dogs and cats. Especially in chronic cases, when extragastrointestinal causes need to be ruled out, it is important to adhere to a systematic workup. This article details the newest available data on tests to aid this diagnostic process. Once the diagnosis of a chronic enteropathy is made, there are many laboratory tests that can help in monitoring the disease and providing prognostic information. Several new tests being evaluated for clinical usefulness are discussed.

Perinuclear antineutrophil cytoplasmic autoantibodies in dogs infected with various vector-borne pathogens and in dogs with immune-mediated hemolytic anemia

OBJECTIVE

To determine the prevalence of perinuclear antineutrophil cytoplasmic autoantibodies (pANCA) in dogs with confirmed or suspected immune-mediated hemolytic anemia (IMHA) or dogs infected with various vector-borne pathogens, including Rickettsia rickettsii, Bartonella henselae, Bartonella vinsonii subsp berkhoffii, Ehrlichia canis, Borrelia burgdorferi, and Leishmania infantum.

ANIMALS

55 dogs with confirmed or suspected IMHA, 140 dogs seroreactive for vector-borne pathogens, and 62 healthy dogs and dogs seronegative for vector-borne pathogens.

PROCEDURES

Samples were allocated to subgroups on the basis of the health status of the dogs and the degree of seroreactivity against various vector-borne pathogens. Serum samples were tested retrospectively via indirect immunofluorescence assay to determine pANCA status.

RESULTS

26 of 55 (47%) dogs with confirmed or suspected IMHA and 67 of 140 (48%) dogs seroreactive for vector-borne pathogens had positive results when tested for pANCA. Serum samples with the highest antibody concentrations against L infantum antigen had the highest proportion (28/43 [65%]) that were positive for pANCA. One of 20 (5%) dogs seronegative for tick-borne pathogens and 8 of 22 (36%) dogs seronegative for L infantum had positive results for pANCA. One of 20 (5%) healthy dogs had serum antibodies against pANCA.

CONCLUSIONS AND CLINICAL RELEVANCE

pANCA were detected in a high percentage of dogs with IMHA and vector-borne infectious diseases. Therefore, pANCA may be a relatively nonspecific marker for dogs with inflammatory bowel disease, although they could represent a biomarker for immune-mediated diseases and infections.

Diagnostic utility of abdominal ultrasonography in dogs with chronic diarrhea

BACKGROUND

Chronic diarrhea is common in dogs and has many causes. Ultrasonographic descriptions of many gastrointestinal diseases have been published, but the diagnostic utility of ultrasonography in dogs with chronic diarrhea has not been investigated.

HYPOTHESIS

Diagnostic utility of abdominal ultrasound will be highest in dogs with GI neoplasia and lowest in those with inflammatory disorders.

ANIMALS

87 pet dogs with chronic diarrhea.

METHODS

Prospective study in which medical records were reviewed and contribution of abdominal ultrasound toward making diagnosis was scored.

RESULTS

In 57/87 (66%) of dogs, the same diagnosis would have been reached without ultrasonography. In 13/87 (15%) of dogs, the ultrasound examination was vital or beneficial to making the diagnosis. Univariable analysis identified that increased diagnostic utility was associated with weight loss (P = .0086), palpation of an abdominal or rectal mass (P = .0031), diseases that commonly have mass lesions visible on ultrasound examination (P < .0001), and a final diagnosis of GI neoplasia. Multivariable regression indicated that utility of abdominal ultrasonography would be 30 times more likely to be high in dogs in which an abdominal or rectal mass was palpated (odds ratio 30.5, 95% CI 5.5-169.6) (P < .0001) versus dogs without a palpable mass. In 15/87 (17%) of dogs, additional benefits of ultrasonography to case management, independent of the contribution to the diagnosis of diarrhea, were identified.

CONCLUSIONS AND CLINICAL IMPORTANCE

Overall, the diagnostic utility of abdominal ultrasonography was low in dogs with chronic diarrhea. Identification of factors associated with high diagnostic utility is an indication to perform abdominal ultrasonography in dogs with chronic diarrhea.

Evaluation of perinuclear antineutrophilic cytoplasmic antibodies in sera from dogs with inflammatory bowel disease or intestinal lymphoma

OBJECTIVE

To assess and compare the expression of perinuclear antineutrophilic cytoplasmic antibodies (pANCA) in sera obtained from dogs with inflammatory bowel disease (IBD) and dogs with intestinal lymphoma.

ANIMALS

104 dogs with IBD and 23 dogs with intestinal lymphoma.

PROCEDURES

Each ill dog had persistent gastrointestinal signs (> 3 weeks in duration) and absence of response to diet changes or antimicrobial treatments. Gastrointestinal endoscopy was performed in ill dogs to obtain intestinal biopsy specimens for histologic confirmation of IBD or lymphoma. A serum sample was obtained from each ill dog. Neutrophils were isolated from a blood sample from the healthy dog; neutrophil-bearing slides were incubated with serum from each ill dog and examined for expression of pANCA by use of an indirect immunofluorescence technique. Detection of cells that had a perinuclear fluorescence pattern was considered a positive result.

RESULTS

The 2 groups of dogs did not differ with regard to breed and sex but did differ with regard to age. Expression of pANCA was detected in 38 of the 104 (36.5%) dogs with IBD and 4 of the 23 (17.4%) dogs with intestinal lymphoma. Although the frequency of pANCA expression was higher in dogs with IBD, compared with findings in dogs with intestinal lymphoma, the difference was not significant.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that circulating pANCA are present in some dogs with IBD or intestinal lymphoma. However, pANCA detection does not seem to be useful for distinguishing dogs with IBD from dogs with intestinal lymphoma.

Pitfalls and progress in the diagnosis and management of canine inflammatory bowel disease

Inflammatory bowel disease (IBD) is the collective term for a group of chronic enteropathies characterized by persistent or recurrent gastrointestinal (GI) signs and inflammation of the GI tract. The specific steps that lead to IBD and the basis for phenotypic variation and unpredictable responses to treatment are not known. This article examines IBD in dogs, focusing on the interaction between genetic susceptibility and the enteric microenvironment (bacteria, diet), the utility of recently developed histologic criteria, the prognostic indicators, and the standardized approaches to treatment.

Clinical immunology and immunopathology of the canine and feline intestine

The mucosal immune system is at the forefront of defense against invading pathogens, but at the same time, it must maintain tolerance toward commensals and food antigens in the intestinal lumen. The interplay between the innate immune response and commensal microorganisms is essential to maintaining this balance. Great progress has been made in identifying some of the genetic predispositions underlying inflammatory bowel disease in certain breeds, such as the German shepherd dog. Several immunologic markers are discussed with respect to their clinical usefulness in the diagnosis and management of inflammatory bowel disease.

Laboratory tests for the diagnosis and management of chronic canine and feline enteropathies

Chronic enteropathies are commonly encountered in both cats and dogs. Although definitive diagnosis often requires collection of gastrointestinal biopsies for histopathologic evaluation, less invasive laboratory tests can be highly informative and should be performed prior to biopsy collection. Tests for determination of infectious causes comprise those for helminthic, protozoal, bacterial, or fungal organisms. Intestinal function and disease may be assessed by measuring serum concentrations of cobalamin, folate, and C-reactive protein, and fecal concentrations of α(1)-proteinase inhibitor. Ongoing research has led to development of tests for serum perinuclear antineutrophilic cytoplasmic antibodies, and fecal inflammatory markers, including S100-proteins and N-methylhistamine.

Detection of Perinuclear Antineutrophil Cytoplasmic Antibodies and Antinuclear Antibodies in the Diagnosis of Canine Inflammatory Bowel Diseas

In recent years, serologic markers for diagnosis and classification of inflammatory bowel disease (IBD) have been used in human medicine. Perinuclear, antineutrophil, cytoplasmic antibodies (p-ANCA) are the most important of these markers. Because of their similar pattern of fluorescence, antinuclear antibodies (ANA) could cause misleading interpretations. The aim of the present study was to evaluate the use of an indirect fluorescent antibody test to detect p-ANCA in dogs with IBD, to compare the presence of p-ANCA in dogs with IBD with the presence of the same antibodies in other dogs, and to analyze the presence of ANAs in the p-ANCA-positive samples. Using a 1:10 dilution as a cutoff point, a sensitivity of 0.34 and a specificity of 0.86 was obtained when dogs with IBD were compared with the other groups as a whole, and specificity increased to 0.94 when dogs with IBD were compared with animals with other chronic gastrointestinal disorders. The lowest specificity value, 0.76, was obtained when the group of dogs with IBD was compared with that of dogs with different inflammatory and infectious disorders. Globally, 78 dogs were positive for p-ANCA when the cutoff was 1:10. Only 1 dog from these 78 animals was also seropositive to ANA. The results suggest that 1) detection of p-ANCA might be included in the IBD diagnostic protocol as another test to differentiate between this disease and other digestive diseases with similar clinical signs, and 2) most p-ANCA- positive dogs are not ANA positive.

Comparison of oral prednisone and prednisone combined with metronidazole for induction therapy of canine inflammatory bowel disease: a randomized-controlled trial

BACKGROUND

Although prednisone and metronidazole are commonly used to treat canine inflammatory bowel disease (IBD), no randomized-controlled trials have been performed.

HYPOTHESIS

Combination drug therapy with prednisone and metronidazole will be more effective than prednisone alone for treatment of canine IBD. Reduction in disease severity will be accompanied by decreased canine IBD activity index (CIBDAI) scores and serum C-reactive protein (CRP) concentrations.

ANIMALS

Fifty-four pet dogs diagnosed with IBD of varying severity.

METHODS

Dogs were randomized to receive oral prednisone (1 mg/kg; n = 25) or prednisone and metronidazole (10 mg/kg; n = 29) twice daily for 21 days. Clinical (CIBDAI) scores and serum CRP were determined at diagnosis and after 21 days of drug therapy. The primary efficacy measure was remission at 21 days, defined as a 75% or greater reduction in baseline CIBDAI score.

RESULTS

Differences between treatments in the rate of remission (both exceeding 80%) or the magnitude of its change over time were not observed. CRP concentrations in prednisone-treated dogs were increased because of many dogs having active disease. Both treatments reduced CRP in comparison with pretreatment concentrations. An interaction between CIBDAI and CRP was identified in 42 of 54 dogs (78%), whereas 8 of 54 dogs (15%) showed disagreement between these indices.

CONCLUSIONS AND CLINICAL IMPORTANCE

Prednisone is as effective as combined treatment with prednisone and metronidazole for induction therapy of canine IBD. CRP may be normal or increased in dogs with IBD and may be useful in assessing the response of individual dogs to treatment along with changes in the CIBDAI.

Activation of nuclear factor-kappaB in dogs with chronic enteropathies

Homeostasis in the intestinal microenvironment between the immune system and luminal antigens appears disturbed in chronic enteropathies. Pro-inflammatory cytokines likely play a role in the pathogenesis of intestinal inflammation. Several inflammatory and immunoregulatory genes have associated nuclear factor-kappaB (NF-kappaB) binding sites, which allow NF-kappaB to regulate gene transcription. The purpose of this study was to investigate (1) the occurrence of NF-kappaB activation during mucosal inflammation in situ, (2) the mucosal distribution pattern of cells expressing activated NF-kappaB within treatment groups, and (3) the effect of specific therapy on NF-kappaB activation. Dogs with chronic enteropathy were studied (n=26) and compared with 13 healthy dogs. Ten dogs had food responsive disease (FRD) and 16 had inflammatory bowel disease (IBD). NF-kappaB activation was detected in duodenal mucosal biopsies using a mouse monoclonal antibody (MAB 3026) that selectively binds the nuclear localization sequence of activated NF-kappaB. To identify macrophages, biopsies were stained using the MAC 387 antibody. Macrophages in the lamina propria double-stained for MAC 387 and NF-kappaB were quantitated; epithelial cell expression of activated NF-kappaB was determined semi-quantitatively. Results showed that more macrophages positive for activated NF-kappaB were present in lamina propria of dogs with chronic enteropathy compared to control dogs (p<0.01). More NF-kappaB positive epithelial cells were observed in FRD dogs compared to IBD dogs (p<0.05). After therapy, the number of macrophages and epithelial cells staining positive for activated NF-kappaB decreased (p<0.01) in chronic enteropathy dogs. In conclusion, activation of NF-kappaB is closely associated with the pathophysiology of canine chronic enteropathy. Down-regulation follows successful therapy.