Evaluation of urinalysis as an aid in the diagnosis of equine grass sickness

To determine whether urinalysis can aid the diagnosis of equine grass sickness, samples of urine from 15 horses with acute grass sickness, eight horses with subacute grass sickness, 17 co-grazing horses and 17 stabled control horses were analysed. The samples from all of the horses with grass sickness had a significantly higher specific gravity, higher protein and creatinine concentrations and a significantly lower pH; the samples from the horses with acute grass sickness also had significantly higher glucose concentrations. These differences may support a diagnosis of grass sickness but they are not pathognomonic for the disease.     

Oral endoscopy as an aid to diagnosis of equine cheek tooth infections in the absence of gross oral pathological changes: 17 cases

Reasons for performing study: Removal of cheek teeth in all but the aged horse or pony is a serious undertaking with potentially deleterious sequellae. Rigid endoscopy permits detailed examination of the oral cavity and erupted dental tissues and has the potential to assist in the correct identification of the diseased tooth. Objectives: To document oral endoscopic findings associated with infected equine cheek teeth in cases without gross oral pathological changes and thereby determine the usefulness of rigid oral endoscopy as an aid to diagnosis of such infections. Methods: Records of all cases of equine cheek tooth removal attempted under standing sedation over a 38 month period were examined. Cases were excluded from the study if apical infection was associated with gross dental fracture, malalignment, diastema/periodontal pocketing or supernumerary teeth. Endoscopic and radiographic findings were analysed and correlated to diseased tooth location. Results: Seventeen cases of apical dental infection fitting the inclusion criteria (nonresponsive to antibiotics and with no gross oral abnormality of the affected arcade) were identified in which oral endoscopy was used as an aid to diagnosis. In 15 (88%) of the 17 cases, oral endoscopy revealed abnormalities specific to the infected tooth. Focal gingival recession (10/17 cases) was the most common visible abnormality associated with infected teeth. Conclusions: In the majority of cases of apical infection of equine cheek teeth there is visible intraoral evidence implicating the affected tooth. Potential relevance: Oral endoscopy facilitates detailed examination of the mouth and should be considered along with radiography as an important aid to diagnosis in cases of equine dental infection.     

Extra-adrenal paraganglioma of the equine orbit: six cases

At The Ohio State University from 1994–2006 six of seven horses evaluated for primary orbital disease were diagnosed with extra-adrenal paraganglioma (EAPG). The horses ranged in age from 14 to 24 years, with a mean of 16.8 years. Duration of clinical signs was 1.5 years to 5 years, with a mean of 2.8 years. Clinical signs varied, but all six had non-painful exophthalmus of the right eye. Five horses had complete ocular exams reported; three of five had decreased to absent vision, two of five had pale optic nerves, and in three of five, difficulty of retropulsion of the globe was noted. Diagnostic tests performed included complete blood count, serum profile, radiography, ultrasound, computed tomography, true-cut biopsy, ocular examination, guttural pouch endoscopy, oral examination, and physical examination. Expulsive hemorrhage during orbital exenteration occurred in all horses. In five of six cases, tumor extension through the orbital foramen was apparent intra-operatively. Histopathologic appearance of all surgically removed tissues consisted of sheets of polygonal cells with abundant lightly granular cytoplasm, round nuclei with vesicular chromatin, and rare mitoses. Neoplastic cells were arranged into small groups separated by a fine fibrovascular stroma. All six cases were chromagranin positive on immunohistochemical staining. Follow-up ranged from six months to six years, with a mean of two years. Four of the five horses that recovered from surgery had no apparent tumor recurrence in 6–48 months.     

Electromyography under caudal epidural anaesthesia as an aid to the diagnosis of equine motor neuron disease

Electromyography was used as an aid to the diagnosis of equine motor neuron disease in a conscious horse while it was under caudal epidural anaesthesia. A muscle biopsy was taken to confirm the diagnosis which was then supported by a postmortem examination.     

Electron microscopy as an aid to the rapid diagnosis of virus diseases of veterinary importance

The use of electron microscopy to assist in the rapid diagnosis of virus diseases of veterinary importance is reviewed. Electron microscopy can be used to assist the laboratory diagnosis of a virus disease at two stages during the investigation; either by demonstrating virus in clinical material or by identifying isolates from tissue culture or similar systems. Direct electron microscopy and immunoelectron microscopy are particularly useful for rapid diagnosis. The advantages of electron microscopy lie in speed and flexibility, and the disadvantages in the high particle concentration needed and the presumptive nature of a diagnosis.     

Fistulography as an aid in the diagnosis of a nonradiopaque foreign body in a dog

A case of chronic fistula associated with foreign body penetration of the soft tissues was diagnosed in the skull of a dog by fistulography. Radiographic technique and diagnostic features are described and illustrated.     

Diagnosis of equine arteritis virus infection in two horses by using monoclonal antibody immunoperoxidase histochemistry on skin biopsies

Two 5-year-old grade male horses presented with epiphora, rhinorrhea, conjunctival and nasal mucosal hyperemia, and dorsal and thoracic macropapular rash. Skin biopsies were collected from the affected areas, and serial sections were evaluated following hematoxylin and eosin and immunoperoxidase histochemistry staining by using a murine monoclonal antibody of the immunoglobulin G2A isotype recognizing the 30-kDa membrane protein of equine arteritis virus (EAV). In both horses, lesions consisted of mild to moderate diffuse superficial dermal edema and vasculitis with mild perivascular lymphocytic infiltrates, occasional endothelial hypertrophy, and single-cell necrosis of tunica media myocytes. Immunohistochemically, a few endothelial cells, myocytes, and pericytes containing intracytoplasmic EAV antigen were identified. Immunoperoxidase histochemistry of skin biopsies can be used as an ancillary test for the clinical diagnosis of equine viral arteritis in horses, especially when a cutaneous macropapular rash is evident.     

Potential role of multiple rectal biopsies in the diagnosis of equine grass sickness

Two samples were taken postmortem from the rectum of each of 14 horses with grass sickness and 10 control horses, and four sections stained with haematoxylin and eosin were examined. By using as a criterion of grass sickness the presence of three chromatolytic neurons, 10 of the 14 cases were positive and none of the control horses was positive, giving a sensitivity of 71 per cent and a specificity of 100 per cent. No other histological features appeared to be of diagnostic value, and staining for Nissl substance in neurons with cresyl fast violet and methyl green-pyronin did not improve the sensitivity of the test.     

Googling for a veterinary diagnosis: A replication study using Google as a diagnostic aid

BackgroundThe purpose of this study was to replicate in the veterinary context a BMJ study using Google to assist in diagnosis of complex cases.Hypothesis/ObjectivesTo assess percentage of diagnoses identified using Google as a diagnostic aid in veterinary medicine.AnimalsNone; 13 cases in cats and 17 in dogs published in JAVMA.MethodsCross‐sectional survey of Google results from searches using keywords generated independently by a generalist and a specialist veterinarian who reviewed the published case history and diagnostic components while blind to the diagnosis. They offered diagnoses and generated up to 5 search strategies for each case. The top 30 Google results for each search were reviewed by the generalist to inform a final Google‐aided diagnosis. Both veterinarians'' initial diagnoses and the Google‐aided diagnoses were compared with the published diagnoses.ResultsGoogle searching led to 52 diagnoses out of 60 possible. Twenty‐two (42%, 95% confidence interval [95% CI] 29%‐55%) Google‐aided diagnoses matched the JAVMA diagnosis. This accuracy rate does not differ significantly from 58% (n = 15/26, 95% CI 38%‐77%) identified in the BMJ study. Google‐aided results were not statistically different from those achieved unaided by each veterinarian (33%, 95% CI 16%‐50%).Conclusions and Clinical ImportancePublished information found searching Google using keywords related to complicated or unusual cases could assist veterinarians to reinforce their initial diagnosis or consider other differential diagnoses. Search strategies using words representing either signs or the preliminary diagnoses can yield results useful to confirming a correct diagnosis.     

Barium swallow as an aid to the diagnosis of grass sickness

Twenty-five horses, suspected on clinical grounds of having grass sickness, were given a barium swallow. Using image intensification the passage of the barium bolus was followed radiographically from the pharynx to the stomach. All 18 horses in which grass sickness was later confirmed at post mortem examination showed defective oesophageal motility. Although the specificity of the abnormality could not be proven, the technique offers a valuable aid to the ante mortem diagnosis of grass sickness.     

Intradermal tests as an aid to the diagnosis of skin disease in dogs

The diagnosis and treatment of skin disease form a major part of the small animal practitioner's work. A significant number of cases will be allergic in nature and may present difficulties in diagnosis. In man, skin testing for allergy is an established aid to diagnosis, but has been little used by the small animal veterinarian; published results are few. This paper is a preliminary report of the results of skin tests using allergens on normal and allergic dogs. It is considered that the method is of value as an aid to the diagnosis of flea hypersensitivity, but that the preliminary results using other allergens are inconclusive. Résumé. Le diagnostic et le traitement de dermatoses constituent une partie importante du travail du vétérinaire spécialisé dans le traitement d'animaux domestiques. De par la nature allergique d'un nombre considérable de cas, leur diagnostic peut poser des problèmes. Chez l'homme, les essais dermiques pour déterminer l'allergie sont reconnus comme facilitant le diagnostic; les vétérinaires, toutefois, n'y ont pas souvent recours et rares sont les résultats publiés dans ce domaine. Cette communication est un rapport préliminaire des résultats qu'ont fournis les essais dermiques en usant des allergènes chez des chiens normaux et ailergiques. On estime que la méthode a de la valeur en ce sens qu'elle aide à établir le diagnostic de l'hypersensibilité aux puce, mais que les résultats préliminaires avec d'autres allergènes sont peu concluants. Zusammenfassung. Die Diagnose und die Behandlung von Hautkrankheiten stellen einen grossen Teil der Arbeit des praktkchen Tierarztes dar. Eine nicht unbedeutende Zahl von Fällen wird allergischer Natur sein und kann diagnostische Schwierigkeiten bieten. Beim Menschen ist die Prüfung der allergischen Reaktion der Haut ein anerkanntes Mittel der Diagnose, das jedoch in der tierärztlichen Praxis wenig angewendet wurde, und auch Veröffentlichungen über die Ergebnisse sind selten. Die vorliegende Arbeit ist ein vorläufiger Bericht über die Ergebnisse von Hauttests unter Verwendung von Allergenen an normalen und allergischen Hunden. Man darf annehmen, dass die Methode einen Wert als diagnostisches Hilfsmittel im Falle der Überempfindlichkeit gegen Flöhe besitzt, dass die vorläufigen Ergebnisse der Verwendung anderer Allergene aber nicht eindeutig sind.     

Microfocal radiography as an aid to the diagnosis of canine elbow osteochondrosis

One normal cadaver specimen and six labrador retrievers with suspected elbow osteochondrosis were examined using a microfocal radiographic technique as an aid to diagnosis. This allowed the production of a magnified image (macro-radiograph) with high spatial resolution. The macroradiographs were compared with radiographs obtained using a standard technique to see if they facilitated decision making with respect to case management. The lesions that were suspected from radiographic examination were correlated with the gross lesions found at elbow arthrotomy. Microfocal radiography gave additional information about the changes within the joints but it still remained difficult to image the lesion satisfactorily in some cases.