A presumptive case of gluten sensitivity in a border terrier: a multisystem disorder?

Canine paroxysmal dyskinesia-a review

Paroxysmal dyskinesias (PDs) are a group of involuntary, hyperkinetic movement disorders that recur episodically and may last seconds to hours. An important feature of PD is that there is no loss of consciousness during the episode. Using a clinical classification, three main types of PDs have been distinguished in canine PD: (1) paroxysmal kinesigenic dyskinesia (PKD) that commences after (sudden) movements, (2) paroxysmal non-kinesigenic dyskinesia (PNKD) not associated with exercise and can occur at rest, and (3) paroxysmal exertion-induced dyskinesia (PED) associated with fatigue. Canine PDs are diagnosed based on the clinical presentation, history, and phenomenology. For the latter, a video recording of the paroxysmal event is extremely useful. An etiological classification of canine PDs includes genetic (proven and suspected), reactive (drug-induced, toxic, metabolic, and dietary), structural (neoplasia, inflammatory, and other structural causes), and unknown causes. In this review, an overview of all reported canine PDs is provided with emphasis on phenotype, genotype, and, where possible, pathophysiology and treatment for each reported canine PD.

Long-term nutritional management of an obese German Spitz with paroxysmal dyskinesia, calcium oxalate urolithiasis, and suspected pancreatitis—A case report

Background

To our knowledge, this is the first description of long-term nutritional management in a dog with paroxysmal dyskinesia.

Case summary

An obese 9-year-old, male entire, German Spitz was presented for dietary management after being diagnosed with calcium oxalate urolithiasis and suspected pancreatitis. Since he was seven years old, the dog has had a history of neurological signs, which were thought to be epileptic seizures. He was treated with phenobarbital and potassium bromide and was clinically controlled. For his nutritional advice, aiming to minimize one of the most important risk factors for the diseases, a weight loss program was started and successfully executed. However, 10 months later, the dog restarted presenting neurological episodes at a high frequency (3x/week). Based on videos and the characteristics of the neurological signs, the dog was diagnosed with paroxysmal dyskinesia. To investigate the role of gluten intake on this patient's neurological signs, a dietary trial with a commercial hypoallergenic diet (gluten-free; hydrolyzed protein) was followed. During the 3 months of the dietary trial, four neurologic episodes related to food indiscretion occurred. Upon the decrease in neurological episodes, the anti-seizure drugs were slowly discontinued. During this period, the dog presented only two neurologic episodes that were related to the days that the anti-seizure drugs were decreased. For 4 months the dog remained episode-free. However, a change in the dog's diet to another gluten-free diet (higher fat) led the dog to vomit and experience another neurologic episode. Once the dog was back to the previous gluten-free diet, it clinically improved, and no other clinical signs were reported by the client during the next 5 months.

Conclusion

Although a relationship between gluten and paroxysmal dyskinesia cannot be confirmed, the dog's improvement after the nutritional management and the removal of the anti-seizure therapy is supportive of dietary association.

Novel association of gluten sensitivity with immune-mediated neuromuscular syndrome in a dog

Gluten-related disorders in humans comprise different entities, including coeliac disease. Patients typically have measurable titers of anti-gliadin IgG or IgA (AGAs) and anti-transglutaminase-2 IgA (TG2). In addition to intestinal symptoms, human patients often show various neurological complications. In dogs, the neurological manifestation is rarely reported. Here we describe the muscle and nerve biopsies of an 11-year-old, male Border Terrier presenting with lower motor neuron signs submitted for histological examination. Examination of the biopsies showed an oligofocal lymphohistiocytic and plasmocytic myositis and a diffuse neuropathy of mixed nodo-paranodal and demyelinating type. Suspecting a neuromuscular form of breed-related gluten hypersensitivity, measurements of AGAs and TG2 antibodies were performed. Both titers ranged above control values. Hence, a gluten-related neuromyopathy was diagnosed. A gluten-free diet was prescribed and a complete disappearance of clinical signs was observed. Gluten-related disorders should be considered as a differential diagnosis in dogs with intestinal and neuromuscular signs.

Current diagnostics for chronic enteropathies in dogs

Chronic enteropathies (CEs) in dogs describe a group of idiopathic disorders characterized by chronic persistent or recurrent gastrointestinal (GI) signs. Three major subgroups of CE can be identified by their response to treatment: Food-responsive disease (FRD), antibiotic-responsive disease (ARD), and steroid-responsive disease (SRD). The clinical diagnosis of CE is made by exclusion of all other possible causes of chronic diarrhea and includes histologic assessment of intestinal biopsies. The process of diagnosing canine CE can therefore be very time-consuming and expensive, and in most cases, does not help to identify dogs that will respond to a specific treatment. The development of novel diagnostic tests for canine CE has therefore focused on the accuracy of such tests to predict treatment responses. In this article, several novel assays that have the potential to become commercially available will be discussed, such as genetic tests, perinuclear anti-neutrophil cytoplasmic antibodies (pANCA), antibodies against transglutaminase/gliadin, antibodies against E coli OmpC/flagellin, and micro RNAs.

Serological markers of gluten sensitivity in Border terriers with gall bladder mucocoeles

OBJECTIVES

To evaluate serological markers of gluten sensitivity in conjunction with cholecystokinin measurement in Border terriers with gall bladder mucocoeles.

MATERIALS AND METHODS

Medical records from two referral hospitals were obtained between 2011 and 2019 to identify Border terriers with gall bladder mucocoeles, non-Border terriers with gall bladder mucocoeles and control Border terriers with non-biliary diseases. Enzyme-linked immunosorbent assays were performed on stored fasted serum samples for anti-gliadin IgG, anti-canine transglutaminase-2-IgA autoantibodies and cholecystokinin. Statistical analysis was performed using the Kruskall-Wallis test to identify differences between the groups.

RESULTS

Fifteen Border terriers with gall bladder mucocoeles, 17 non-Border terriers with gall bladder mucocoeles and 14 control Border terriers with non-biliary diseases were recruited. Median transglutaminase-2-IgA autoantibodies in Border terriers with gall bladder mucocoeles was 0.73 (range: 0.18 to 1.67), which was significantly greater than in control Border terriers at 0.41 (0.07 to 1.14). Median cholecystokinin concentration in Border terriers with gall bladder mucocoeles was 13 pg/mL (6 to 45 pg/mL), which was significantly lower than in control Border terriers at 103 pg/mL (9 to 397 pg/mL). There was no difference in the anti-gliadin IgG between these groups. There was no difference observed in the non-Border terriers with gall bladder mucocoeles with either of the other groups.

CLINICAL SIGNIFICANCE

Reduced cholecystokinin and increased transglutaminase-2-IgA autoantibodies was detected in Border terriers with gall bladder mucocoeles; which is in part homologous to gall bladder disease identified in human coeliac disease. The results suggest an immunological disease with impaired cholecystokinin release may be affecting gall bladder motility and possibly contributing to mucocoele formation in Border terriers.

Phenotypic characterization of paroxysmal dyskinesia in Maltese dogs

Background

Paroxysmal dyskinesias (PDs) are a group of central nervous system diseases characterized by episodes of abnormal involuntary hyperkinetic movement without altered consciousness that increasingly have been recognized in dogs.

Objectives

To present the phenotypical characterization, treatment, and outcome of a PD observed in Maltese dogs.

Animals

Client‐owned Maltese dogs (n = 19) with presumed diagnosis of PD.

Methods

Data were collected retrospectively from medical records (2014‐2019), and supporting information was added prospectively by using a questionnaire directed to the owners of the affected dogs.

Results

The episodes were characterized mainly by sudden dystonia of ≥1 limbs and generalized body tremors with preserved consciousness. The mean age of clinical onset was 5.4 years. Episode frequency varied widely both among and within individuals. Median episode duration was 4.5 minutes. Most episodes were stress‐ or exercise‐induced. Acetazolamide was administered to 6 dogs, and 4 dogs experienced a decrease in episode frequency. In 7 dogs that received a gluten‐free diet, 6 dogs became episode‐free. In 4 dogs, the episodes stopped spontaneously and in 2 dogs no medication or specific diet was given and the episodes continued at the same frequency.

Conclusions and Clinical Importance

Given the breed predisposition and regional distribution of the disease, additional research should focus on elucidating the underlying genetic cause doing so might advance both our understanding of the pathophysiology and treatment of this disease, not only in dogs, but also in humans. Regardless of the treatment protocol selected, prognosis appears fair to good.

A multicenter randomized controlled trial of medium-chain triglyceride dietary supplementation on epilepsy in dogs

BACKGROUND

Medium-chain triglyceride (MCT) enriched diet has a positive effect on seizure control and behavior in some dogs with idiopathic epilepsy (IE).

OBJECTIVE

To evaluate the short-term efficacy of MCTs administered as an add-on dietary supplement (DS) to a variable base diet to assess seizure control and antiseizure drug's (ASD) adverse effect profiles.

ANIMALS

Twenty-eight dogs with International Veterinary Epilepsy Task Force Tier II (IVETF) level diagnosis of treated IE with 3 or more seizures in the last 3 months were used.

METHODS

A 6-month multicenter, prospective, randomized, double-blinded, placebo-controlled crossover trial was completed, comparing an MCT-DS with a control-DS. A 9% metabolic energy-based amount of MCT or control oil was supplemented to the dogs' diet for 3 months, followed by a control oil or MCT for another 3 months, respectively. Dogs enrolled in this study satisfied most requirements of IE diagnosis stated by the IVETF II level. If they received an oil DS or drugs that could influence the metabolism of the investigated DS or chronic ASD, the chronic ASD medication was adjusted, or other causes of epilepsy were found, the dogs were excluded from the study.

RESULTS

Seizure frequency (median 2.51/month [0-6.67] versus 2.67/month [0-10.45]; P = .02) and seizure-day frequency were significantly (1.68/month [0-5.60] versus 1.99/month [0-7.42], P = .01) lower when dogs were fed MCT-DS in comparison with the control-DS. Two dogs were free of seizures, 3 had ≥50% and 12 had <50% reductions in seizure frequency, and 11 dogs showed no change or an increase in seizure frequency.

CONCLUSIONS AND CLINICAL IMPORTANCE

These data show antiseizure properties of an MCT-DS compared to a control oil and support former evidence for the efficacy of MCTs as a nutritive, management option for a subpopulation of drug-resistant dogs with epilepsy.

Characterization of Paroxysmal Gluten-Sensitive Dyskinesia in Border Terriers Using Serological Markers

BACKGROUND

Paroxysmal gluten-sensitive dyskinesia (PGSD) in border terriers (BTs) results from an immunologic response directed against transglutaminase (TG)2 and gliadin. Recent evidence suggests that PGSD is only one aspect of a range of possible manifestations of gluten sensitivity in the breed.

HYPOTHESIS/OBJECTIVES

Gluten sensitivity in BTs is a heterogeneous disease process with a diverse clinical spectrum; to characterize the phenotype of PGSD using TG2 and gliadin autoantibodies as diagnostic markers.

ANIMALS

One hundred twenty-eight client-owned BTs with various disorders.

METHODS

Prospective study. BTs with paroxysmal episodes and a normal interictal examination were phenotyped using footage of a representative episode and assigned to 3 groups: idiopathic epilepsy (IE), paroxysmal dyskinesia (PD), or other. Owners of each dog completed a questionnaire to obtain information regarding clinical signs. Healthy BTs formed a control group. Serum antibodies against TG2 and AGA were measured in all dogs.

RESULTS

One hundred twenty-eight BTs were enrolled; 45 with PD, 28 with IE, 35 with other conditions, and 20 controls. Three overlapping phenotypes were identified; PD, signs suggestive of gastrointestinal disease, and dermatopathy. AGA-IgG concentrations were increased in PD, compared with IE (P = 0.012), controls (P < 0.0001) and other (P = 0.018) conditions. Anti-canine TG2-IgA concentrations were increased in PD, compared with IE (P < 0.0001), controls (P < 0.0001) and other (P = 0.012) conditions. Serological markers are highly specific for PGSD but lack sensitivity.

CONCLUSIONS

PGSD appears part of a syndrome of gluten intolerance consisting of episodes of transient dyskinesia, signs suggestive of gastrointestinal disease, and dermatological hypersensitivity.