Mario Ricciardi

Neurological manifestations in dogs naturally infected by Leishmania infantum: descriptions of 10 cases and a review of the literature

In order to evaluate possible nervous system involvement in canine leishmaniasis, retrospective evaluation of all medical records of leishmaniotic dogs exhibiting neurological signs referred to our hospital over a 5-year period was performed. The records of 10 dogs were reviewed. Depending on the neuroanatomical localisation, the dogs underwent advanced diagnostic imaging, cerebrospinal fluid analysis, electrodiagnostic testing and histopathologic evaluations. The final neurological diagnosis was: meningoencephalitis (n=2), brain haemorrhagic stroke (n=1), haemorrhagic choroiditis (n=1), meningomyelitis (n=2), ischaemic myelopathy (n=1), polymyositis (n=2) and peripheral neuropathy (n=1). This study confirms that both central and peripheral nervous systems can be affected by leishmaniasis and provides an overview on the possible etiopathogenetic mechanisms. In addition, clinical and diagnostic findings, therapy and follow-up of affected dogs are described.

Bilateral cervical ribs in a Dobermann Pinscher

An 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.

Imaging diagnosis-bilateral abnormal ossification of the supraglenoid tubercle and cranial glenoid cavity in an English Setter.

An 8-month-old intact male English Setter was presented with bilateral shoulder lameness. Radiographic and CT examinations demonstrated bilateral irregular margination and separation of the supraglenoid tubercle from the scapula, with involvement of the cranial articular surface of the glenoid cavity. After 30 days of cage rest, complete fusion of proximal portions of both supraglenoid tubercles and persistent un-united cranial portions of both glenoid cavities were evident. Histopathologic findings from biopsies of glenoid cavity defects were consistent with osteochondrosis or focal chondrodysplasia.

Usefulness of spinal unenhanced computed tomography and CT-myelography in the age of multidetector CT technology and magnetic resonance imaging - Preliminary considerations

Over the last decade, magnetic resonance imaging (MRI) and multidetector computed tomography (MDCT) have revolutionized diagnostic potential in small animal practice, providing adequate assessment of spinal diseases at levels comparable to that achieved in human radiology. T2-weighted MRI images are extremely sensitive to intramedullary parenchymal disorders, while balanced steady-state free precession sequences provide high-quality myelographic images of the spine without the need of intrathecal contrast medium administration. Multidetector computed tomography, with its near-isotropic spatial resolution and multiplanar reformatting of the acquired datasets, provides sufficient stratigraphic details of the spinal cord and the epidural space, facilitating the detection of compressive pathologies without the need of subarachnoid opacification. Nowadays, MDCT and low-field (LF) MRI have become fairly standard and available in academic institutions and private veterinary facilities, appearing to be valuable, complementary, and non-invasive diagnostic tools for imaging the spine. In this scenario, this clinical communication provides a series of preliminary observations that may help to reconsider the usefulness of CT-myelography in the light of its invasiveness and actual diagnostic advantages compared to MRI and unenhanced MDCT for the assessment of compressive and non-compressive spinal diseases in small animals.

A novel encephalopathy in a thiamine-deficient dog resembling human Wernicke’s disease with atypical MRI pattern

Thiamine is a water-soluble vitamin, which participates in several vital metabolic pathways involved in energy metabolism and neurotransmitter synthesis of mammals. In companion animals thiamine deficiency is classically associated with signs of diffuse encephalopathy and lesions on brainstem nuclei and mesencephalic colliculi evident on magnetic resonance imaging. This paper describes a novel clinical presentation in a thiamine-deficient dog showing multifocal, central and peripheral nervous and cardiovascular system alterations. Brain MRI showed bilateral caudate nuclei damage, with necrotic-malacic evolution, similar to the atypical MRI pattern found in Wernicke’s encephalopathy in humans. Detection of bilateral symmetrical lesions of the caudate nuclei in dogs should prompt consideration of a thiamine deficiency among the differential diagnoses.

Spontaneous nervous system concussion in dogs: A description of two cases and a review of terminology in veterinary medicine

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.

Unusual haemodynamics in two dogs and two cats with portosystemic shunt - implications for distinguishing between congenital and acquired conditions

Extrahepatic porto-systemic shunt (PSS) in small animals can be congenital (CPSS) or acquired (APSS) as a consequence of portal hypertension (PH), and are distinguished on the bases of their anatomical pattern. A precise morphologic imaging assessment, along with clinical and histopathologic findings, is important for distinguishing patients with PH from those with congenital PSSs, which require different therapeutic approach. Expected findings in patients with PH are presence of ascites, multiple APSS, and a confirmed cause of portal flow obstruction. On the other hand, a single PSS, absence of ascites and no evidence of portal vein, caudal vena cava or hepatic disorders are typical findings of CPSS patients. This paper describes four cases of PSSs in which the combination of the computed tomographic imaging findings did not match the standards for APSS nor for CPSS: one dog had chronic hepatitis causing PH and ascites and a splenoazygos PSS, to date considered a CPSS pattern. One dog showed a left splenogonadal PSS and porto-caval varices, to date considered an APSS pattern, without ascites, portal vein obstruction, primary structural hepatic disorders nor evidence of PH. Two cats, with and without diffuse hepatic structural disorders respectively, had a single left splenogonadal PSS without ascites. Possible interpretation of such unusual haemodynamic conditions and clinical repercussion, especially for orientation of treatment choice, are discussed.

Central vestibular syndrome in a red fox ( Vulpes vulpes ) with presumptive right caudal cerebral artery ischemic infarct and prevalent midbrain involvement

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.

Bilateral Telencephalic Gliomatosis Cerebri in a Dog

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.

Presumptive Ischemic Brain Infarction in a Dog with Evans’ Syndrome

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.