Feline vestibular disorders. Part II: diagnostic approach and differential diagnosis.

Results of a neurological examination usually permit localisation of a vestibular disorder to either the central or peripheral parts of the vestibular system. Many different disorders located in the same part of the vestibular system will produce similar clinical signs. Therefore, additional diagnostic tests beyond a neurological examination are required in order to make an accurate diagnosis. The objectives of this review are to outline a diagnostic approach for disorders affecting the feline vestibular system, and to summarise the clinically important features of frequently diagnosed diseases affecting the vestibular system of cats

Bronchoscopy, Imaging, and Concurrent Diseases in Dogs with Bronchiectasis: (2003-2014).

BackgroundBronchiectasis is a permanent and debilitating sequel to chronic or severe airway injury, however, diseases associated with this condition are poorly defined.ObjectiveTo evaluate results of diagnostic tests used to document bronchiectasis and to characterize underlying or concurrent disease processes.AnimalsEighty-six dogs that had bronchoscopy performed and a diagnosis of bronchiectasis.MethodsRetrospective case series. Radiographs, computed tomography, and bronchoscopic findings were evaluated for features of bronchiectasis. Clinical diagnoses of pneumonia (aspiration, interstitial, foreign body, other), eosinophilic bronchopneumopathy (EBP), and inflammatory airway disease (IAD) were made based on results of history, physical examination, and diagnostic testing, including bronchoalveolar lavage fluid analysis and microbiology.ResultsBronchiectasis was diagnosed in 14% of dogs (86/621) that had bronchoscopy performed. Dogs ranged in age from 0.5 to 14 years with duration of signs from 3 days to 10 years. Bronchiectasis was documented during bronchoscopy in 79/86 dogs (92%), thoracic radiology in 50/83 dogs (60%), and CT in 34/34 dogs (100%). Concurrent airway collapse was detected during bronchoscopy in 50/86 dogs (58%), and focal or multifocal mucus plugging of segmental or subsegmental bronchi was found in 41/86 dogs (48%). Final diagnoses included pneumonia (45/86 dogs, 52%), EBP (10/86 dogs, 12%) and IAD (31/86 dogs, 36%). Bacteria were isolated in 24/86 cases (28%), with Streptococcus spp, Pasteurella spp, enteric organisms, and Stenotrophomonas isolated most frequently.Conclusions and clinical importanceBronchiectasis can be anticipated in dogs with infectious or inflammatory respiratory disease. Advanced imaging and bronchoscopy are useful in making the diagnosis and identifying concurrent respiratory disease

Clinicopathological characteristics of histiocytic sarcoma affecting the central nervous system in dogs.

BackgroundHistiocytic sarcoma affecting the central nervous system (CNS HS) in dogs may present as primary or disseminated disease, often characterized by inflammation. Prognosis is poor, and imaging differentiation from other CNS tumors can be problematic.ObjectiveTo characterize the clinicopathological inflammatory features, breed predisposition, and survival in dogs with CNS HS.AnimalsOne hundred two dogs with HS, 62 dogs with meningioma.MethodsRetrospective case series. Records were reviewed for results of cerebrospinal fluid (CSF) analysis, CBC, treatment, and outcome data.ResultsPredisposition for CNS HS was seen in Bernese Mountain Dogs, Golden Retrievers, Rottweilers, Corgis, and Shetland Sheepdogs (P ≤ .001). Corgis and Shetland Sheepdogs had predominantly primary tumors; Rottweilers had exclusively disseminated tumors. Marked CSF inflammation was characteristic of primary rather than disseminated HS, and neoplastic cells were detected in CSF of 52% of affected dogs. Increased neutrophil to lymphocyte ratios were seen in all groups relative to controls (P <.008) but not among tumor subtypes. Definitive versus palliative treatment resulted in improved survival times (P < .001), but overall prognosis was poor.Conclusions and clinical importanceClinicopathological differences between primary and disseminated HS suggest that tumor biological behavior and origin may be different. Corgis and Shetland Sheepdogs are predisposed to primary CNS HS, characterized by inflammatory CSF. High total nucleated cell count and the presence of neoplastic cells support the use of CSF analysis as a valuable diagnostic test. Prognosis for CNS HS is poor, but further evaluation of inflammatory mechanisms may provide novel therapeutic opportunities

Eosinophilic bronchitis, eosinophilic granuloma, and eosinophilic bronchopneumopathy in 75 dogs (2006-2016).

BackgroundEosinophilic lung disease is a poorly understood inflammatory airway disease that results in substantial morbidity.ObjectiveTo describe clinical findings in dogs with eosinophilic lung disease defined on the basis of radiographic, bronchoscopic, and bronchoalveolar lavage fluid (BAL) analysis. Categories included eosinophilic bronchitis (EB), eosinophilic granuloma (EG), and eosinophilic bronchopneumopathy (EBP).AnimalsSeventy-five client owned dogs.MethodsMedical records were retrospectively reviewed for dogs with idiopathic BAL fluid eosinophilia. Information abstracted included duration and nature of clinical signs, bronchoscopic findings, and laboratory data. Thoracic radiographs were evaluated for the pattern of infiltrate, bronchiectasis, and lymphadenomegaly.ResultsThoracic radiographs were normal or demonstrated a bronchial pattern in 31 dogs assigned a diagnosis of EB. Nine dogs had intraluminal mass lesions and were bronchoscopically diagnosed with EG. The remaining 35 dogs were categorized as having EBP based on radiographic changes, yellow green mucus in the airways, mucosal changes, and airway collapse. Age and duration of cough did not differ among groups. Dogs with EB were less likely to have bronchiectasis or peripheral eosinophilia, had lower total nucleated cell count in BAL fluid, and lower percentage of eosinophils in BAL fluid compared to dogs in the other 2 groups. In contrast to previous reports, prolonged survival (>55 months) was documented in dogs with EG.Conclusions and clinical importanceDogs with eosinophilic lung disease can be categorized based on imaging, bronchoscopic and BAL fluid cytologic findings. Further studies are needed to establish response to treatment in these groups

Necrotizing meningoencephalitis in atypical dog breeds: a case series and literature review.

BackgroundCanine necrotizing meningoencephalitis (NME) is a fatal, noninfectious inflammatory disease of unknown etiology. NME has been reported only in a small number of dog breeds, which has led to the presumption that it is a breed-restricted disorder.Hypothesis/objectivesOur objective was to describe histopathologically confirmed NME in dog breeds in which the condition has not been reported previously and to provide preliminary evidence that NME affects a wider spectrum of dog breeds than previously reported.AnimalsFour dogs with NME.MethodsArchives from 3 institutions and from 1 author's (BS) collection were reviewed to identify histopathologically confirmed cases of NME in breeds in which the disease has not been reported previously. Age, sex, breed, survival from onset of clinical signs, and histopathologic findings were evaluated.ResultsNecrotizing meningoencephalitis was identified in 4 small dog breeds (Papillon, Shih Tzu, Coton de Tulear, and Brussels Griffon). Median age at clinical evaluation was 2.5 years. Histopathologic abnormalities included 2 or more of the following: lymphoplasmacytic or histiocytic meningoencephalitis or encephalitis, moderate-to-severe cerebrocortical necrosis, variable involvement of other anatomic locations within the brain (cerebellum, brainstem), and absence of detectable infectious agents.Conclusions and clinical importanceUntil now, NME has only been described in 5 small dog breeds. We document an additional 4 small breeds previously not shown to develop NME. Our cases further illustrate that NME is not a breed-restricted disorder and should be considered in the differential diagnosis for dogs with signalment and clinical signs consistent with inflammatory brain disease

Congenital myasthenic syndrome in Golden Retrievers is associated with a novel COLQ mutation.

BackgroundCongenital myasthenic syndromes (CMSs) are a group of inherited disorders of neuromuscular transmission that may be presynaptic, synaptic, or postsynaptic. Causative mutations have been identified in 4 breeds including the Labrador Retriever, Jack Russell Terrier, Heideterrier, and Danish Pointing Dog.Hypothesis/objectiveClinical and genetic characterization of a neuromuscular disorder in Golden Retriever (GR) puppies.AnimalsFour GR puppies from California were evaluated for generalized muscle weakness beginning at weaning. Biological specimens were collected from the affected puppies, and familial information was obtained. Blood or buccal swabs were obtained from 63 unaffected GRs.MethodsComplete physical, neurological, electrodiagnostic, and histological evaluations and biochemical quantification of muscle acetylcholine receptors were performed. Polymerase chain reaction was used to amplify the 17 exons of COLQ, and sequences were obtained by Sanger sequencing. Variant frequency was assessed in unrelated GRs and a public database.ResultsClinical, neurological, and electrodiagnostic evaluations confirmed a disorder of neuromuscular transmission in a GR family. Sequencing of all exons and splice sites of a primary candidate gene, COLQ, identified a point mutation that predicts an amino acid substitution (G294R). The primary COLQ transcript was absent from affected muscle samples. All affected puppies were homozygous for the mutation, which was not detected outside this GR family or in other breeds.Conclusions and clinical importanceWe confirmed the diagnosis of a CMS in GR puppies and identified a novel COLQ mutation. The COLQ gene encodes the collagenous tail of acetylcholinesterase, the enzyme responsible for termination of skeletal muscle contraction by clearing acetylcholine at the neuromuscular junction. Clinicians and breeders should be aware of this CMS in GR puppies with an early onset of weakness

Whole genome sequencing for mutation discovery in a single case of lysosomal storage disease (MPS type 1) in the dog.

Mucopolysaccharidosis (MPS) is a metabolic storage disorder caused by the deficiency of any lysosomal enzyme required for the breakdown of glycosaminoglycans. A 15-month-old Boston Terrier presented with clinical signs consistent with lysosomal storage disease including corneal opacities, multifocal central nervous system disease and progressively worsening clinical course. Diagnosis was confirmed at necropsy based on histopathologic evaluation of multiple organs demonstrating accumulation of mucopolysaccharides. Whole genome sequencing was used to uncover a frame-shift insertion affecting the alpha-L-iduronidase (IDUA) gene (c.19_20insCGGCCCCC), a mutation confirmed in another Boston Terrier presented 2 years later with a similar clinical picture. Both dogs were homozygous for the IDUA mutation and shared coat colors not recognized as normal for the breed by the American Kennel Club. In contrast, the mutation was not detected in 120 unrelated Boston Terriers as well as 202 dogs from other breeds. Recent inbreeding to select for recessive and unusual coat colors may have concentrated this relatively rare allele in the breed. The identification of the variant enables ante-mortem diagnosis of similar cases and selective breeding to avoid the spread of this disease in the breed. Boston Terriers carrying this variant represent a promising model for MPS I with neurological abnormalities in humans