Changes in saliva analytes in equine gastric ulcer syndrome (EGUS) after treatment: a pilot study

Equine gastric ulcer syndrome (EGUS) is a prevalent condition in horses, affecting up to 93% of racehorses. Comprising the equine squamous gastric disease (ESGD) and the equine glandular gastric disease (EGGD), EGUS poses significant health challenges. Saliva, a non-invasive and easily obtainable sample, is increasingly recognized for its potential as a source of biomarkers in horses. This study investigates changes in saliva analytes using automated assays before and after EGUS treatment, aiming to identify biomarkers indicative of treatment success or failure. A total of 28 horses diagnosed with EGUS were treatment with omeprazole for six weeks and further divided into successful (n = 15) or unsuccessful (n = 13) treatment group. Saliva samples were collected before and after treatment, and analytes related to enzymes, metabolites, proteins, redox biomarkers, and minerals were measured using an automated chemistry analyzer. Results revealed that horses with successful treatment, indicated by reduced EGGD and ESGD scores, showed significant increases in bicarbonate and urea, and decreases in adenosine deaminase (ADA), and creatine kinase (CK). Conversely, horses with non-successful treatment showed no significant changes in salivary analytes. These analytes have the advantages of an easy and fast measurement and the possibility of being applied in routine. Further studies with larger populations should be performed to establish the possible practical application of these analytes as biomarkers of treatment.

Prevalence and Risk Factors for the Presence of Gastric Ulcers in Pleasure and Breeding Horses in Italy

Equine Squamous Gastric Disease (ESGD) and Equine Glandular Gastric Disease (EGGD) are two terms used to indicate the presence of lesions of the squamous and glandular mucosa of the stomach. Prevalences, pathophysiology, and risk factors are different, and the latter have been investigated in different populations. The aim of this study was to investigate the prevalence and risk factors of ESGD and EGGD in a cohort of pleasure, breeding, and retired horses in Italy. To the authors' knowledge, this is the first study to investigate such a diverse population of animals and the first one that includes a large number of animals in Italy. Gastroscopies were performed in 316 animals, with and without clinical signs of gastric ulcers, and a questionnaire about signalment, management, activity, and health was given to the owners or caretakers. Prevalence of ESGD was similar to the current literature reports in comparable populations, and the disease was associated with signalment, time with the current owner or caretaker, management (time and type of paddock, hay, and supplementary feed administered), and activity performed. In this population, EGGD was present in a lower percentage of animals and, of the parameters evaluated, was associated only with the signalment, while management does not seem to influence the development of lesions in the glandular mucosa in this population.

Is There a Difference in the Prevalence of Gastric Ulcers between Stallions Used for Breeding and Those Not Used for Breeding?

Equine gastric ulcer syndrome (EGUS) is a worldwide disease, and includes two different syndromes, Equine Squamous Gastric Disease (ESGD), affecting the squamous mucosa, and Equine Glandular Gastric Disease (EGGD), affecting the glandular mucosa. These two diseases are present in different categories (different activities, ages, etc.) and breeds of horses. The effect of sex on gastric health is not clear: some studies found a higher prevalence of ESGD in geldings and stallions, while others found no influence of sex on the squamous mucosa. The few studies conducted on glandular diseases failed to identify sex as a risk factor. The only study on breeding horses, focused on Thoroughbred mares at pasture, found that 70% of them were affected by gastric ulcerations especially in the squamous mucosa. The aim of this study was to determine the prevalence of EGUS, ESGD, and EGGD in intact males while also investigating the potential influences of breeding and exercise activity on the occurrence and severity of the diseases. A total of 101 intact males were admitted for gastroscopic examination. Comprehensive data regarding their breeding and sports history, management, and presence of clinical signs were recorded. A statistical analysis was performed. Within this equine population, no discernible relationship was found between breeding activity and occurrence and severity of ESGD or EGGD. Exercise and a combination of exercise and breeding activities were found to be associated with the occurrence of EGGD. The presence of clinical signs was correlated only with the grade of ESGD in this cohort of horses.

Presence of Gastric Ulcers in Horses Used for Historical Races in Italy

Equine Gastric Ulcers Syndrome (EGUS) is a worldwide disease present in equids of different breeds, activity levels, and age groups. It is divided into two different illnesses: Equine Squamous Gastric Disease (ESGD) affecting the squamous mucosa and Equine Glandular Gastric Disease (EGGD) affecting the glandular mucosa. The historical horserace is a traditional competition that is common in Italy. They can be divided into two different types: speed races and jousting tournaments. Anglo-Arabians and Thoroughbreds are used for the two competitions with training and management systems similar to those used in races performed on a racetrack. The aim of this study was to determine the prevalence of ESGD and EGGD in horses used for historical horseracing and evaluate the differences in the presence of the diseases in animals of the two different breeds used for the two types of competition. A cohort of 73 horses was enrolled in this study, which were stabled in 10 training facilities and performed two jousting tournaments and one speed race. An ESGD at least of grade 2 was found in 88% of horses with all degrees of severity seen; EGGD was diagnosed in 45% of animals. In this cohort of horses, the presence and severity of ESGD and EGGD are similar to that in reports in racehorses performing on racetracks. Anglo-Arabians used for speed races are more affected by ESGD and EGGD, which is probably because they are involved in a higher number of races and travel more during the year compared to Thoroughbreds used for jousting competitions.

Changes in the saliva proteome analysed by gel-proteomics in horses diagnosed with equine gastric ulcer syndrome (EGUS) at diagnosis and after successful treatment

Equine gastric ulcer syndrome (EGUS) is currently one of the more frequent diseases in horses. We aimed to identify changes in the salivary proteome in horses with EGUS at diagnosis and after successful treatment by using gel proteomics. Saliva samples were collected from nine horses with EGUS before and after treatment and nine matched healthy controls. SDS-PAGE (1DE) and two-dimensional gel electrophoresis (2DE) were performed, and significantly different protein bands and spots were identified by mass spectrometry. Horses with EGUS had increases in proteins such as adenosine deaminase (ADA), triosephosphate isomerase, keratins and immuno-globulin heavy constant mu and decreases in carbonic anhydrase (CA), albumin and prolactin-induced protein. These changes would indicate various physiopathological mechanisms involved in this disease, such as the activation of the immune system, decreased stomach defence mechanisms and inflammation. The treated horses presented lower expression levels of thioredoxin (TRX) after a successful treatment, in proteomics analysis and also measured with a commercially available ELISA kit. Overall, horses with EGUS have protein changes in their saliva when measured with gel proteomics compared with healthy horses, and they also showed changes after successful treatment. These proteins could be potential biomarkers for detection and monitoring treatment response in EGUS.

Five- versus seven-day dosing intervals of extended-release injectable omeprazole in the treatment of equine squamous and glandular gastric disease

BACKGROUND

An extended-release injectable omeprazole formulation (ERIO) has become a popular treatment for equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD) where it is available; however, published data are limited and optimal treatment regimens have not been determined.

OBJECTIVES

To compare effects of treatment on ESGD and EGGD when an ERIO formulation is administered at either 5- or 7-day intervals.

STUDY DESIGN

Retrospective clinical study.

METHODS

Case records and gastroscopy images of horses with ESGD or EGGD treated with ERIO were reviewed. Images were anonymised and graded by one researcher masked to treatment group. Treatment responses were compared between the two treatment schedules using univariable ordered logistic regression.

RESULTS

Forty-three horses were treated with ERIO at 5-day intervals and 39 horses at 7-day intervals. Signalment and presenting signs did not differ between groups. The proportions of horses with EGGD healing (to grade 0 or 1) in association with ERIO used at 5-day intervals (93%) were higher than associated with treatment at 7-day intervals (69%; odds ratio [OR]: 2.41, 95% CI: 1.23-4.74, p = 0.01). For ESGD, there was no significant difference in the proportion of horses healing in association with treatment at 5-day intervals (97%) compared with 7-day intervals (82%; OR: 2.75, 95% CI: 0.91-8.31, p = 0.07). Four of 328 injections were associated with an injection-site reaction (1%).

MAIN LIMITATIONS

Retrospective study design, lack of randomisation and limited case numbers.

CONCLUSIONS

The use of ERIO at 5-day intervals might be more appropriate than the 7-day interval that is used currently.

The effects of feeding sodium chloride pellets on the gastric mucosa, acid-base, and mineral status in exercising horses

BACKGROUND

Electrolyte supplementation may be a risk factor for gastric mucosal lesions, but relevant evidence is limited in horses.

HYPOTHESIS

Investigate the effects of PO sodium chloride (NaCl) supplementation on the gastric mucosa of exercising horses. We hypothesized that NaCl supplementation would neither cause nor exacerbate existing gastric mucosal damage.

ANIMALS

Fifteen 3-year-old healthy Warmblood stallions from a stud farm.

METHODS

Placebo-controlled study with a crossover design. Horses were fed either a NaCl pellet at a dosage adequate to replace the electrolyte losses in 10 L sweat or a placebo for 19 days with a washout period of 14 days between treatments. The gastric mucosa was evaluated by gastroscopy before and after treatment. Blood samples were collected for evaluation of acid-base status, packed cell volume (PCV), and total protein, creatinine and blood urea nitrogen concentrations. Urine was collected, and urine specific gravity, electrolyte, creatinine, and urea concentrations were measured.

RESULTS

The initial prevalence of gastric mucosal lesions was 85%. Sodium chloride pellets did not adversely affect the gastric mucosa and treatment did not significantly alter the hematologic and serum biochemical variables. Urine creatinine concentrations significantly decreased and urinary sodium concentrations significantly increased after supplementation with NaCl pellets. Water intake did not significantly differ between treatments.

CONCLUSIONS AND CLINICAL IMPORTANCE

Daily NaCl pellet supplementation is a palatable and safe way to replace electrolyte losses from sweating in exercising horses and has no negative effects on the gastric mucosa.

Comparison of oral esomeprazole and oral omeprazole in the treatment of equine squamous gastric disease

BACKGROUND

Oral omeprazole is the accepted treatment for equine squamous gastric disease (ESGD); however, it is not universally effective. Esomeprazole results in more consistent and pronounced acid suppression in men and is more effective than omeprazole in the treatment of oesophageal and gastric disease. Pharmacodynamic and pilot clinical studies have indicated esomeprazole might also be more effective than omeprazole in horses.

OBJECTIVES

To compare the efficacy and safety of oral esomeprazole and omeprazole pastes in the treatment of ESGD and, where present, concurrent equine glandular gastric disease (EGGD).

STUDY DESIGN

Randomised, single-blinded controlled trial.

METHODS

Horses presenting with grade ≥2 ESGD lesions were randomly allocated to receive 4 mg/kg of either a buffered esomeprazole or omeprazole paste orally once daily for 28 days before gastroscopy being repeated within a further 3 days. Videos and images were anonymised and subsequently graded blind by one researcher. The severity of ESGD (and EGGD) lesions before and after treatment, and thereby treatment responses, were compared using univariable logistic regression.

RESULTS

A higher proportion of horses had ESGD healing in response to esomeprazole treatment (63/74, 85%) than with omeprazole treatment (43/73, 59%) (odds ratio [OR]: 4.00, 95% confidence interval [CI]: 1.81, 8.82, p = 0.001). In a subset of horses that had concurrent EGGD, a greater proportion of the horses treated with esomeprazole had lesions ≤grade 1 (esomeprazole 28/51, 55%; omeprazole 6/24, 25%; OR: 3.65, 95% CI: 1.25, 10.71, p = 0.02) Using grade 0 as the benchmark for EGGD healing, the difference remained significant (OR: 4.44, 95% CI: 1.33, 14.85, p = 0.02).

MAIN LIMITATIONS

It may not be possible to extrapolate these results to other populations with different signalment or management.

CONCLUSIONS

Oral-buffered esomeprazole was a more effective treatment for ESGD (and concurrent EGGD) than oral-buffered omeprazole.

A Comparison of the Efficacy of Two Omeprazole Formulations in the Treatment of Equine Gastric Ulcer Syndrome in Racehorses: A Blinded, Randomized Clinical Trial

Equine gastric ulcer syndrome (EGUS) is the most common disease of the stomach in horses and treatment is based on the oral administration of omeprazole for at least 28 days. Aim of this study was to compare the efficacy of two formulations of oral omeprazole-powder paste and gastro-enteric resistant granules-in the treatment of naturally occurring gastric ulcers in racehorses. Thirty-two adult racehorses, aged between 2 and 10 years old, with clinical signs of EGUS were included in this blinded, randomized clinical trial. Two gastroscopies were performed to evaluate gastric lesions in the squamous or glandular mucosa before and after 28 days of treatment. After the first gastroscopy, 2/32 horses were excluded because affected by equine squamous gastric disease (ESGD) 1/4. The remaining horses were divided into 4 groups, and were treated with 2 formulations of omeprazole (gastroenteric resistant granules, group 1, or powder paste, group 3) or with 2 placebo formulations (granules, group 2, or paste, group 4). Treatments were performed in the placebo horses affected by ESGD or equine glandular gastric disease after the T28 gastroscopy control. No differences were found between groups at T0. Differences were found between T0 vs. T28 for granular (P = .002) and powder paste (P = .01) formulations. No differences were detected between the two groups receiving omeprazole formulations at T28 (0.34) and between T0 vs. T28 for either of the groups receiving placebo treatments. For all the variables, the size of the effect was greater than 0.5, proving that the treatments had a considerable effect. Gastro-enteric resistant granules and powder paste omeprazole showed similar efficacy in the treatment of ESGD. The glandular mucosa responded poorly to treatment with omeprazole.

Current Topics in Medical Colic

The list of medical causes of acute or chronic colic in horses is extensive. The purpose of this article is to review 4 medical causes of equine colic with a focus on newer trends in treatment. The 4 topics selected include gastric impaction, gastric glandular disease, colon displacement, and inflammatory bowel disease.

Body Condition Score Is Not Correlated to Gastric Ulcers in Non-Athlete Horses

Equine Gastric Ulcer Syndrome (EGUS) is a worldwide disease of the stomach that can be found in different categories of horses. Different clinical signs may be present, but a large number of horses are asymptomatic. The aim of this study was to identify a possible correlation between body condition score (BCS) and EGUS in a population of horses. A total of 203 non-athlete horses were submitted for gastroscopies, and the presence and severity of lesions of the glandular and squamous mucosa were recorded. A board-certified veterinarian blinded to the gastroscopy results assessed the BCS of the horse. In the study population, no correlation was found between BCS and the presence of gastric lesions in either the glandular or the squamous mucosa. The disease of the squamous or glandular mucosa cannot be excluded based only on the presence of normal or increased BCS in non-athlete horses.

Changes in Proteins in Saliva and Serum in Equine Gastric Ulcer Syndrome Using a Proteomic Approach

Simple Summary

Equine gastric ulcer syndrome (EGUS) is a highly prevalent disease with a major clinical importance due to its negative effects on the welfare and performance of horses. EGUS can be distinguished into two different diseases depending on which anatomical region is affected: equine glandular gastric disease (EGGD), in which there is a lesion in the glandular stomach, and equine squamous gastric disease (ESGD), in which the alteration appears in the non-glandular stomach. EGUS has nonspecific clinical signs, and its underlying mechanism has not been completely elicited. Therefore, it would be of interest to clarify the pathophysiology and identify potential biomarkers of this syndrome. This study detected differences in the salivary and serum proteome between horses with EGUS and healthy horses, and also between horses with EGGD and ESGD. The most upregulated proteins in EGGD were related to the immune activation whereas, in horses with ESGD, the proteins with the most significant changes were associated with the squamous cell regulation and growth. Compared to serum, saliva had a higher number of proteins showing significant changes and also showed a different pattern of changes, indicating that the proteins in both fluids show a different response to the disease and can provide complementary information.

Abstract

Changes in the salivary proteome in 12 horses with the two diseases included in equine gastric ulcer syndrome (EGUS), equine glandular gastric disease (EGGD) (n = 6) and equine squamous gastric disease (ESGD) (n = 6), were evaluated using a high-resolution LC-MS/MS analysis of TMT-labelled peptides and compared to 10 healthy control horses. Serum was also analysed for comparative purposes. The comparison between the horses with EGGD and controls showed significant changes in 10 salivary proteins, whereas 36 salivary proteins were differently abundant between ESGD and control groups. The most upregulated proteins in the case of EGGD were related to immune activation whereas, in horses with ESGD, the most significantly changed proteins were associated with squamous cell regulation and growth. Compared to serum, saliva showed a higher number of proteins with significant changes and a different pattern of changes. The proteins identified in our study, in addition to providing new information about the pathophysiological mechanisms in these diseases, could have the potential to be novel biomarkers for the diagnosis or monitoring of EGGD and ESGD.

A study comparing the healthy and diseased equine glandular gastric microbiota sampled with sheathed transendoscopic cytology brushes

BACKGROUND

The role of the equine gastrointestinal microbiota in the pathogenesis of equine glandular gastric disease (EGGD) is poorly understood.

OBJECTIVES

To investigate whether the glandular gastric microbiota is altered in horses with EGGD.

STUDY DESIGN

Prospective longitudinal study METHODS: Five Thoroughbred racehorses from one training centre underwent gastroscopy as part of poor performance investigation. Samples were taken from EGGD lesions and adjacent normal mucosa using sheathed transendoscopic cytology brushes and frozen at -80 °C. DNA was extracted for 16S rRNA sequencing, and sequences compared against a database to generate taxonomic classification of the microbiota. The same horses were sampled six months later.

RESULTS

Normal glandular mucosal samples were characterised by a higher proportion of Proteobacteria (46.3 %) than EGGD lesions (18.9 %). Relative abundance of Firmicutes was lower in samples from normal mucosa (20.0 %) than EGGD lesions (41.2 %). Linear discriminant analysis effect size (LEfSe) confirmed a greater proportion of Firmicutes species was characteristic of samples collected from EGGD lesions due to a very high relative abundance of Sarcina (up to 92.4 %) in two horses with EGGD. We were unable to comment on the stability of the glandular gastric microbiota over time.

MAIN LIMITATIONS

Small sample population. None of the horses examined had grossly normal gastric mucosa.

CONCLUSIONS

The gastric microbiota appears altered in EGGD, although we are unable to demonstrate a causative effect. Sarcina was particularly increased in abundance in EGGD and may be a useful biomarker of disease. Sheathed cytology brushes were an effective method for sampling the gastric mucosa.

Assessment of agreement using the equine glandular gastric disease grading system in 84 cases

Introduction

Equine glandular gastric disease (EGGD) is a common condition causing signs of gastric pain although lesions are highly variable in their appearance. The only definitive method to diagnose EGGD ante‐mortem is gastroscopy. The current recommended method for describing these lesions is the European College of Equine Internal Medicine (ECEIM) guidelines; however, repeatability between users is variable. This study aimed to validate the reliability of lesion descriptions using ECEIM consensus guidelines, using four blinded equine internal medicine diplomates.

Methods

Ninety‐two horses with EGGD with pre‐ and post‐treatment gastroscopy images were identified using the electronic record at a UK equine hospital between 2012 and 2019. Eight horses were excluded due to non‐diagnostic images. Four blinded observers used the recommended grading system to describe images and outcomes. Intraclass correlation coefficients and Krippendorff's alpha were used to determine reliability and agreement, respectively.

Results

Intraclass correlation coefficient for severity was 0.782 (95% confidence interval [CI] 0.722–0.832), for distribution was 0.671 (95% CI 0.540–0.763), for the descriptor raised was 0.635 (95% CI 0.479–0.741), fibrinosuppurative was 0.745 (95% CI 0.651–0.812), haemorrhagic was 0.648 (95% CI 0.513–0.744), hyperaemic was 0.389 (95% CI 0.232–0.522) and for outcome was 0.677 (95% CI 0.559–0.770). Krippendorff's alpha for severity was 0.466 (95% CI 0.466–0.418), for distribution was 0.304 (95% CI 0.234–0.374), for the descriptor raised was 0.268 (95% CI 0.207–0.329), fibrinosuppurative was 0.406 (95% CI 0.347–0.463), haemorrhagic was 0.287 (95% CI 0.229–0.344), hyperaemic was 0.112 (95% CI 0.034–0.188) and for outcome was 0.315 (95% CI 0.218–0.408).

There was moderate reliability determined between observers using intra‐class correlation coefficients and unacceptable agreement determined between observers using Krippendorff's alpha.

Discussion

These results suggest that the current grading system is not comparable between observers, indicating the need to review the grading system or define more robust criteria.

Evaluation of the treatment of equine glandular gastric disease with either long-acting-injectable or oral omeprazole

Background

Equine glandular gastric disease (EGGD) is common in domesticated horses and can be challenging to treat. Oral omeprazole (ORLO) is used widely but the clinical response is frequently poor.

Objectives

To compare rates of EGGD healing and improvement between ORLO and a long‐acting injectable omeprazole preparation (LAIO).

Study design

Retrospective clinical study.

Methods

The case records and gastroscopy images of horses presenting to masked for peer review over a 12‐month period were reviewed, with images blindly assessed by one of the authors. Treatment responses to 4 mg/kg LAIO administered every 7 days for 2 and 4 weeks were compared with ORLO 4 mg/kg PO q24hrs for 4 weeks. Data were compared using a Mann‐Whitney U test with post‐hoc Dunn's test, Chi‐squared test and a Fisher's exact test.

Results

Thirty‐three horses that received LAIO and 12 that received ORLO were identified. Nine horses in the LAIO had received other treatments previously. The groups were comparable in signalment and EGGD lesion severity. Long‐acting injectable omeprazole was found to be non‐inferior to ORLO. LAIO was associated with better healing rates than ORLO at 4 weeks (LAIO‐80%; ORLO‐42%; p = 0.02), and reduction in lesion severity at 2 and 4 weeks in the LAIO group but not in the ORLO group at 4 weeks. Eighteen percent of horses in the LAIO group and 50% in the ORLO group did not heal at 4 weeks. There was no association between rate of healing or improvement and resolution or improvement of clinical signs. Six localised and self‐limiting injection site reactions were identified in 4 horses treated with LAIO (6.7%).

Main limitations

Retrospective design, small numbers and the use of other treatments prior to use of LAIO.

Conclusions

LAIO was found to be non‐inferior to oral omeprazole for EGGD. Larger blinded randomised clinical trials are justified.

Equine glandular gastric disease (EGGD) is common in domesticated horses and can be challenging to treat. Long‐acting injectable omeprazole was found to be non‐inferior to ORLO. LAIO was associated with better healing rates than ORLO at 4 weeks (LAIO‐80%; ORLO‐42%; p = 0.02), and reduction in lesion severity at 2 and 4 weeks in the LAIO group but not in the ORLO group at 4 weeks.

Gastric microbiome in horses with and without equine glandular gastric disease

Background

The role of the gastric microbiome in development or persistence of equine glandular gastric disease (EGGD) remains to be investigated.

Hypothesis/Objectives

The objective was to characterize the glandular mucosal and gastric fluid microbiomes of horses with and without EGGD. It was hypothesized that differences in the mucosal microbiome are associated with EGGD.

Animals

Twenty‐four horses were enrolled.

Methods

Gastroscopy was performed and EGGD scores recorded (score 0, n = 6; score 1, n = 8; score ≥2, n = 10). Gastric fluid and pinch biopsies of healthy glandular mucosa and EGGD lesions were collected via gastroscope. 16S rRNA amplicon sequencing of the gastric fluid and glandular mucosal biopsies was performed. Relationships between gastric fluid and mucosal microbial community composition were evaluated among EGGD score groups (EGGD 0‐BX, EGGD 1‐BX, EGGD ≥2‐BX) and among endoscopic appearances: controls from horses without EGGD and normal areas, hyperemic areas, and lesions from horses with EGGD.

Results

Microbial community structure of mucosal biopsies differed among EGGD score groups (Jaccard similarity index; P = .009). Principal coordinate analysis showed separate clusters for EGGD 0‐BX and EGGD ≥2‐BX.

Conclusions and Clinical Importance

A modest difference was detected in the community structure of the gastric glandular mucosal microbiome in association with EGGD score.

Evaluation of a questionnaire to detect the risk of developing ESGD or EGGD in horses

Equine gastric ulcer syndrome (EGUS) affects various categories of horses worldwide. This syndrome is now divided into two different diseases, based on the presence of lesions on either the squamous (Equine Squamous Gastric Disease, ESGD) or the glandular (Equine Glandular Gastric Disease, EGGD) mucosa. Diagnosis is based on the evaluation of the presence of gastric lesions with gastroscopic examination. As a gastroscopy can be considered expensive by clients, therapy is started often on the basis of clinical signs only. The aim of this study was to validate a questionnaire to detect the risk of developing ESGD or EGGD. The owners of 418 horses that were submitted to gastroscopic evaluation were asked to answer a questionnaire on risk factors for ESGD and EGGD. Horses were divided into three groups based on the results of the questionnaire and their risk of developing gastric lesions. In our population the survey was not useful to detect the presence and the severity of the lesions detected during gastroscopic examination, however answers to some of the questions did correlate with the development of gastric lesions. The questionnaire could therefore be a useful tool to evaluate the risk of ESGD or EGGD. Having owners periodically complete the survey could also make them more aware of changes in the conditions of the horses that could lead to gastric lesions. This could then help them seek advice from veterinarians on how to manage this potential risk.

Inter-observer variability of two grading systems for equine glandular gastric disease

BACKGROUND

Equine glandular gastric disease (EGGD) is recognised as a separate entity to equine squamous gastric disease (ESGD) and it is recommended that lesions are graded differently. Currently, no validated scoring system exists for EGGD.

OBJECTIVES

To determine inter-observer reliability of two previously described grading systems for EGGD and to assess if agreement improved with gastroscopy experience, specialist training or familiarity with the descriptive system.

STUDY DESIGN

Cross-sectional survey.

METHODS

A link to an electronic questionnaire containing 20 images of glandular lesions was circulated. Respondents were asked to score lesions using descriptive terminology and a 0-2 verbal rating scale (VRS). Krippendorff's alpha reliability estimate was used to assess inter-rater agreement. A mixed effects model was used to determine which descriptive categories were associated with lesions being described as severe and decision to treat.

RESULTS

Eighty-two veterinarians responded, 49 diplomates and 33 non-diplomates. There was no agreement when all four descriptive variables were combined (α = 0.19). Agreement was fair to moderate for severity (α = 0.52), distribution (α = 0.44), appearance (α = 0.38) and shape (α = 0.32). Agreement for the VRS was similar to that for severity (α = 0.53). Agreement was better among diplomates across all categories. Lesion appearance and shape, but not distribution, were associated with both a decision to treat; and lesions being described as severe (P =< .05). A VRS score 2/2 was associated with a lesion being described as severe (OR 75.2, 95% CI 51.12-110.48, P =< .001).

MAIN LIMITATIONS

Intra-observer variability was not assessed. The number of images is relatively small, and the decision to treat is based on several factors in practice.

CONCLUSIONS

Overall, agreement for the descriptive system was poor. Better delineation of descriptive category boundaries and characteristics should be determined. Agreement was similar when comparing the severity category and the VRS. Extrapolation to a VRS based on lesion severity may therefore be possible.