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Background: Canine thymomas are associated with multiple paraneoplastic syndromes, among which myasthenia gravis is the most common. Acquired myasthenia gravis is an autoimmune disease characterized by the presence of antibodies against acetylcholine receptors. Acetylcholine receptors antibodies are the most commonly formed, but the production of antistriational antibodies binding to skeletal and cardiac muscle proteins has also been recorded both in humans and dogs. An association between the occurrence of antistriational antibodies and a severe form of myocarditis, giant cell myocarditis, has been described in humans. Case Description: A 4-year-old mixed-breed dog was referred because of one month history of exercise-induced weakness, hypersalivation and regurgitation. The neurologic examination was indicative of a neuromuscular junction disease, and myasthenia gravis was suspected. A Computed Tomographic scan examination showed the presence of a megaoesophagus and a thymic mass. Serum antibodies against acetylcholine receptors confirmed the diagnosis of myasthenia gravis. Treatment with pyridostigmine was started, and the thymic mass was surgically excised, and a diagnosis of thymoma was confirmed by histology. 24 hours after surgery, the dog developed a third-degree atrioventricular block. Severe arrhythmia and increased troponin serum levels suggested myocarditis which rapidly led to cardiopulmonary arrest. Histopathologic examination of the heart, esophagus and diaphragm revealed a lymphocytic and macrophagic infiltration, consistent with myocarditis and polymyositis. Scattered rare giant multinucleated cells were also detected in the myocardium. Conclusions: To the author’s knowledge, this is the first report of thymoma-associated myasthenia gravis with concurrent polymyositis and giant cell-like myocarditis in a dog.

A wild young male red fox (Vulpes vulpes) was found in the mountainous hinterland of Rome (Italy) with a heavily depressed mental status and unresponsive to the surrounding environment. Neurological examination revealed depression, left circling, right head tilt, ventromedial positional strabismus and decreased postural reactions on the left side. Neurological abnormalities were suggestive of central vestibular syndrome. Two consecutive MRIs performed with 30 days interval were compatible with lacunar ischemic infarct in the territory of right caudal cerebral artery and its collateral branches. The lesion epicentre was in the right periaqueductal portion of the rostral mesencephalic tegmentum. Neuroanatomical and neurophysiological correlation between lesion localization and clinical presentation are discussed.Keywords: Mesencephalon, Midbrain, MRI, Stroke, Vulpes vulpes.

The epidemiological characteristics of spontaneous hypercortisolism (HC) were derived from 21,281 client-owned dogs selected from four private veterinary clinics and one university reference center for endocrinology. The odds ratio (OR) method was employed to investigate the risk of developing HC related to breed, gender, and sexual status. The estimated prevalence of HC in the four private clinics was 0.20% [95% confidence interval (CI), 0.13–0.27] and was significantly different compared to the university reference center (1.46%; 95% CI, 1.12–1.80). Sex, breed, and age resulted in risk factors for HC. Mean (± SD) age for dogs with HC was 9.8 (± 2.5) yr. Females had higher risk for HC compared to males (OR 1.85; 95% CI, 1.24–2.75); all neutered dogs (both males and females) had higher risk than intact dogs (OR 2.54; 95% CI, 1.72–3.73); and neutered females had higher risk compared to intact females (OR 2.61; 95% CI, 1.54–4.42). Using the mixed breed dogs as a control population (OR = 1), the risk of developing HC was significantly higher in the Standard Schnauzer (OR 58.1; p < 0.0001) and Fox Terrier (OR 20.33; p < 0.0001). With regard to HC, this study identified an overall prevalence of 0.20%. The data support the existence of sex predisposition, with the highest risk for neutered females.Keywords: Cortisol, Hyperadrenocorticism, Hypercortisolism, PDH

SummaryAn 11-year-old intact female Doberman Pinscher was presented with the complaint of non-ambulatory tetraparesis. Clinical and neurological examination revealed a caudal cervical spinal cord disfunction (C6-T2 spinal cord segments). Magnetic resonance imaging and computed tomographic (CT) findings of the cervical spine were consistent with caudal cervical spondylomyelopathy (CSM). During the diagnostic work-up for the cervical spine, bilateral bone anomalies involving the seventh cervical vertebra and the first ribs were found on radiographs and CT examination. The rib anomalies found in this dog appear similar to cervical ribs widely described in human medicine. In people, cervical ribs are associated with a high rate of stillbirth, early childhood cancer, and can cause the thoracic outlet syndrome, characterized by neurovascular compression at level of superior aperture of the chest. In dogs, only some sporadic anatomopathological descriptions of cervical ribs exist. In this report the radiographic and CT findings of these particular vertebral and rib anomalies along with their relationships with adjacent vasculature and musculature are shown intravitam in a dog. Specific radiographic and CT findings described in this report may help in reaching a presumptive diagnosis of this anomaly. Finally, their clinical and evolutionary significance are discussed.

A 7-year-old intact male mixed dog was presented with a history of acute and progressive paraparesis. Abnormal clinical signs consisted of non-ambulatory paraparesis, hind limbs hypertonia and severe thoracolumbar pain. Magnetic resonance imaging demonstrated an isointense in T1 and T2 WI epidural lesion, with good contrast enhancement, extending from T-10 to T-13. Laminectomy was carried out to remove the epidural mass. Histological examination revealed a pyogranulomatous lesion characterized by numerous macrophages containing yeast-like Grocott and PAS-positive bodies. Immunohistochemistry and PCR performed on formalin-fixed paraffin-embedded tissue confirmed Histoplasma capsulatum as the causative agent. H. capsulatum has a worldwide distribution in temperate and subtropical climates but its presence as an autochthonous fungus in Europe is now recognized. To the authors' knowledge this is the first report of canine histoplasmosis in Italy with lesion confined to the central nervous system.

In human medicine, central nervous system (CNS) concussion is defined as a transient neurological dysfunction following a traumatic event, without evidence of structural abnormalities of the affected region on advanced diagnostic imaging. Depending on the anatomical region involved, three forms of concussive syndromes are described: brain concussion, spinal concussion and cerebellar concussion. Although major textbooks of veterinary neurology admit the existence of canine brain concussion, spontaneous cases of this pathological condition have not been reported in small animals so far. This report describes two cases of concussion in dogs: a 9-month-old, intact male, shih-tzu with brain concussion; and a 10-month-old, intact male, poodle with cerebellar concussion. In addition, a brief review of the definition of the term “concussion” in the veterinary medical literature is provided, in comparison to its meaning in the human medical literature. Finally, this paper proposes an appropriate definition of “concussion” in dogs, that may facilitate clinicians in the recognition of such an elusive syndrome. Keywords : Brain, Computed tomography, Concussion, Dog, Magnetic resonance imaging.

An 8-year-old intact male Lagotto Romagnolo was presented with forebrain signs. Neuroanatomic localization was diffuse prosencephalon. MRI revealed diffuse, bilateral, and symmetric T2 and FLAIR hyperintensities in the parieto-occipital white matter and corpus callosum. No mass effect or contrast enhancement was noted. Analysis of cerebrospinal fluid revealed normal protein content and mild mononuclear pleocytosis. Atypical cells were not identified. 15 days later because of the worsening of clinical condition the patient was euthanized upon owner’s request. Neuropathological investigations were consistent with gliomatosis cerebri (GC). Such an unusual imaging pattern appeared similar to some cases of human GC and to a previous reported case in a dog, suggesting a possible repeatable imaging findings for this rare brain neoplasm. GC should be included in the MRI differentials for diffuse bilateral white matter signal changes and specific MRI findings described in this report may help in reaching a presumptive diagnosis of this tumor.

A ten-year-old neutered female mixed breed dog was referred for pale mucous membrane and acute onset of right prosencephalic clinical signs. Brain magnetic resonance imaging was suggestive for right middle cerebral artery ischemic stroke. Based on cell blood count, serum biochemistry and serologic tests and flow cytometric detection of anti-platelets and anti-red blood cells antibodies, a diagnosis of immunomediated haemolytic anemia associated with thrombocytopenia of suspected immunomediated origin was done. Immunosuppresive therapy with prednisone was started and the dog clinically recovered. Two months later complete normalization of CBC and serum biochemistry was documented. The dog remained stable for 7 months without therapy; then she relapsed. CBC revealed mild regenerative anemia with spherocytosis and thrombocytopenia. A conclusive Evans’ syndrome diagnosis was done and prednisone and cyclosporine treatment led to normalization of physical and CBC parameters. The dog is still alive at the time the paper submitted. Possible thrombotic etiopathogenetic mechanisms are illustrated in the paper and the authors suggest introducing Evans’ syndrome in the differential diagnosis list for brain ischemic stroke in dogs.

A seven-year-old shar-pei dog was referred because of severe lumbosacral pain and faecal incontinence of 20 days' duration. Neurological examination was characterised by plegic tail, absence of perineal reflex, dilated anus, perineum and tail analgesia, and severe lumbosacral pain. The neurological clinical signs were suggestive of a selective lesion involving sacral and caudal spinal cord segments and/or related nerve roots. A magnetic resonance imaging of lumbosacral spine was performed and was suggestive of an intradural lesion. Primary or secondary neoplasia was considered as the most probable differential diagnosis. The dog was euthanased upon the owner's request. Histopathological examination confirmed the presence of an intradural-extramedullary neoplastic tissue enveloping intradural tract of spinal nerve roots. On the basis of histological and immunohistochemical findings, a diagnosis of well-differentiated choroid plexus papilloma was made. To the authors's knowledge, this is the first case of primary or metastatic spinal choroid plexus papilloma in dogs.