Systemic histiocytosis in the Bernese mountain dog

Systemic histiocytosis is a rare familial histiocytic disorder seen in the Bernese mountain dog. This article documents six confirmed cases of the disease seen at the Animal Medical Centre between June 1992 and June 1994 and describes the different presentations of the disease, response to therapy and progression. Three of the dogs are still alive; of these, two are in remission six and 18 months later and in one case the owner refused treatment. Three of the cases were euthanased for humane reasons.     

Systemic histiocytosis in a Bernese mountain dog

Systemic histiocytosis was diagnosed at post mortem examination in a three-year-old Bernese mountain dog born in the United Kingdom. The dog presented with a progressive nodular skin disease, chemosis and periocular swelling occurring over six months. It was unresponsive to topical corticosteroids, antibiotics and oral azathioprine. Elective euthanasia was performed. Post mortem examination revealed extensive histiocytic infiltration of the skin, subcutis and skeletal muscles, particularly of the head.     

Meningeal carcinomatosis in a dog: magnetic resonance imaging features and pathological correlation

A six-year-old cross breed dog was presented with a four-month history of seizure activity, which was unresponsive to anticonvulsive therapy and an acute deterioration in neurological status, evident as central blindness. Cyst-like structures and nodular enhancement within the subarachnoid space were shown on a magnetic resonance image (MRI) scan. Histopathological examination of brain tissue was consistent with meningeal carcinomatosis.     

Clinical and genetic investigations of idiopathic epilepsy in the Bernese mountain dog

A study was conducted to investigate the clinical aspects and to define the mode of inheritance of idiopathic epilepsy in the Bernese mountain dog. Pedigree analyses were carried out on an open, non-preselected population of 4005 dogs. Five different subpopulations with 50 epileptic dogs from 13 generations were included. Almost all epileptic patients showed generalised seizures of the grand-mal type with a well-defined prodromal and postictal phase. The majority (62 per cent) of the epileptic dogs had had their first seizures at between one and three years of age and it was found that the age at first seizure was significantly (P < 0.05) lower in dogs from affected parental animals than in dogs from healthy parental animals. A clear predisposition for males was also noted. Additionally, there was no correlation between inbreeding coefficient and age at first seizure or incidence rate of seizures. The increased occurrence of the disease in different subpopulations and different families of the same sires or dams showed that there was a genetic basis for the condition in the Bernese mountain dog. Furthermore, the results of the pedigree analyses and binomial test support the hypothesis that idiopathic epilepsy has a polygenic, recessive mode of inheritance in the breed. Additional objective test-mating programmes would however be necessary to define the exact mode of inheritance.     

Cervical vertebral instability (wobbler syndrome) in the dog.

Observations on a series of 38 cases (35 Doberman Pinschers and three Great Danes) of the canine wobbler syndrome are described. Radiographic examinations suggested that the primary lesion is an intervertebral instability at C6/7, but with time, secondary changes of the disc degeneration and prolapse and vertebral body malformation causing stenosis of the vertebral canal occur. Cases detected at a young age and showing only the primary lesion were treated successfully, by disc fenestration alone or by disc fenestration and intervertebral screwing. The success rate in older cases with secondary lesions was poor and in this type of case, cord decompression by dorsal laminectomy appears necessary.     

Magnetic resonance imaging characterization of vertebral endplate changes in the dog

Spinal MR images acquired from canine patients over a 7-year period were reviewed for the presence of vertebral endplate changes. Seventy-five dogs with 76 distinct lesions were identified. Presumptive diagnoses fell into five categories: reactive endplate changes (10 dogs/13.2%), discospondylitis (29 dogs/38.2%), vertebral osteochondrosis (7 dogs/9.2%), intravertebral disc herniation (Schmorl's nodes) (4 dogs/5.3%), and fatty infiltration (26 dogs/34.2%). Fatty infiltration occurred significantly more often in small breed dogs (P < 0.001) and tended to be multifocal. The following features were observed in discospondylitis as well as in other nonfatty endplate pathologies: irregular endplates, endplate hyperintensity in T2w or STIR images, reduced endplate signal intensity in T1w SE, variable T1w GRE signal intensity, and endplate contrast enhancement. Overlap between MR characteristics of nonfatty endplate changes should prompt cautious evaluation of adjacent structures.     

Meningioangiomatosis in a dog: magnetic resonance imaging and neuropathological studies

A case of a dog with a long-standing history of seizures is reported. Neurological examination suggested an intracranial focal lesion, while magnetic resonance imaging disclosed a right cerebral mass with ventricular involvement. Pathological analysis of the resected specimen revealed characteristics of meningioangiomatosis.     

Recognition of 'trembler', a hypomyelinating condition in the Bernese mountain dog

An account is given of a hypomyelinating condition, 'trembler', in the Bernese mountain dog. The condition is manifested clinically as a tremor of the limbs and head which becomes more intense with excitement or stress and which disappears with sleep. The tremor, which is first noticeable between two and eight weeks old, may persist throughout life but decline with age. Examination of plastic embedded tissue obtained post mortem from two, nine-week-old animals showed hypomyelination of the spinal cord. Preliminary examination of breeding data suggests that the condition may be inherited as an autosomal recessive.     

Congenital renal dysplasia and psychogenic polydipsia in a Bernese mountain dog.

Congenital renal dysplasia was tentatively diagnosed, based on ultrasound and an intravenous urogram, in a 5-month-old female with polyuria and polydipsia. Creatinine clearance measurement revealed that the renal dysplasia was not the cause of the polyuria. A modified water deprivation test eliminated other differential diagnoses and confirmed psychogenic polydipsia.     

Obstructive struvite ureterolithiasis in 4-month-old intact male Bernese mountain dog

A 4-month-old, 7 kg, intact male, Bernese mountain dog was presented for obstructive struvite ureterolithiasis. Multiple urethroliths, ureteroliths, and urocystoliths were present. Based on an abdominal ultrasound, there was severe left hydronephrosis and hydroureter from distal ureterolith obstruction, just proximal to the vesicoureteral junction. The dog was not azotemic. Successful treatment was accomplished via ventral cystotomy. Bladder wall culture revealed a methicillin-resistant Staphylococcus spp. No predisposing cause was identified. There are no known genetic predispositions in Bernese mountain dogs for struvite urolithiasis. The urinary tract infection resolved with surgical retrieval of the uroliths and antibiotic treatment. The dog remained clinically normal after the cystotomy but developed a subclinical urinary tract infection 4 mo post-operatively.Key clinical message:Urolithiasis is rare in pediatric veterinary patients. To the authors’ knowledge, this is the first report of obstructive ureterolithiasis in a puppy. There is no known genetic predisposition for urolithiasis in Bernese mountain dogs.     

Conventional and functional magnetic resonance imaging features of late subacute cortical laminar necrosis in a dog

Cerebral cortical laminar necrosis (CLN) is a consequence of severe hypoxic, ischemic, or hypoglycemic events. In humans, these cortical lesions show characteristic linear T1‐weighted (T1W) hyperintensity in the late subacute stage. Limited information reporting magnetic resonance imaging (MRI) findings in dogs affected by CLN is available. A 3‐year‐old Belgian Shepherd dog was referred 8 days after sudden onset of blindness after general anesthesia. Neurological examination showed central blindness and mild ataxia. Three‐Tesla MRI examination of the brain revealed bilateral asymmetrical areas of T2‐weighted hyperintensity within the occipital, parietal, temporal, and frontal cortex, involving gray and white matter. Furthermore, linear T1W‐hyperintense lesions were found in the cerebral cortex of the same areas and showed heterogeneous contrast enhancement. Perfusion‐weighted images revealed hyperperfusion in the affected regions. Lesions were compatible with subacute CLN with corresponding edema suspected to be secondary to anesthesia‐related brain hypoxia. Three‐Tesla MRI enabled identification of the laminar pattern of the cortical lesions.     

Malignant histiocytosis in a Bernese mountain dog presenting as a mandibular mass.

A Bernese mountain dog was evaluated because of a gingival mass, multiple abdominal masses, and a pulmonary mass. Malignant histiocytosis was diagnosed based on cytological examination of splenic and bone marrow aspirates and histological examination of a bone marrow biopsy and the gingival mass. The case demonstrates that malignant histiocytosis is difficult to diagnose due to the variety of histiocytic disorders.     

Atlantoaxial cartilaginous exostosis causing spinal cord compression in a mature Bernese mountain dog

Cartilaginous exostosis developed in the atlantoaxial region of a three-and-a-half-year-old Bernese mountain dog. The dog exhibited ataxia in the hindlimbs and flailing movements in the forelimbs. On survey radiographs of the cervical spine there was a focal calcified mass between the dorsal arch of the atlas and the spinous process of the axis. Lumbar myelography revealed severe dorsal spinal cord compression. The mass was removed surgically and the dog made a complete recovery. Histopathology of the excised mass was consistent with a diagnosis of cartilaginous exostosis.