Acquired cervical syringomyelia secondary to a brainstem meningioma in a maltese dog

A 15-year-old female maltese was referred to us because of a 3-month history of ataxia, circling, and acute blindness. A mass was noted in the brainstem on brain magnetic resonance images. A cerebellar herniation was also detected on T1-weighted sagittal images. The lateral, third and fourth ventricles and central canal of the cervical spinal cord were enlarged. Based on diagnostic imaging findings, cervical syringomyelia secondary to a brainstem tumor was suspected. The clinical signs were controlled well by lomustine and the dog survived for 8 months after the initial diagnosis. The mass was diagnosed as a meningioma based on histopathological findings. This report describes the clinical findings and imaging characteristics of an acquired syringomyelia resulting from a brainstem meningioma.     

Acquired urinary bladder diverticulum in a dog

A neutered female chow chow aged six years and five months was evaluated for dysuria. An initial diagnosis of bladder distension and atony was made following physical, ultrasonographic and radiographic examinations. The problems did not resolve with medical management and exploratory surgery revealed a large bladder diverticulum. This report describes the radiographic findings and surgical repair of the acquired bladder diverticulum. The literature available on this condition is also reviewed.     

Hindbrain decompression in a dog with scoliosis associated with syringomyelia

A 6-month-old female Border Collie was examined because of a 1-month history of progressive curvature of the cervical portion of the vertebral column. Radiography revealed severe cervical and thoracic scoliosis. Cervical syringomyelia and hydrocephalus were observed by means of magnetic resonance imaging. Suboccipital craniotomy and laminectomy of the first cervical vertebra were performed, and substantial improvement in the scoliosis and syringomyelia was observed 3 months after surgery. No recurrences were seen during the first year after surgery.     

Acquired canaliculocele with intranasal extension in a dog

To describe a case of a nasolacrimal canaliculocele with intranasal extension in a dog. A 6‐year‐old neutered female Jack Russell Terrier was referred to the Centre Hospitalier Vétérinaire des Cordeliers for a slowly enlarging mass adjacent to the medial canthus of the right eye of 5 months duration. Ophthalmic exam, ultrasound, fine needle aspiration, dacryocystorhinography and computerized tomography examinations were performed. Rhinoendoscopic treatment with marsupialisation of the endonasal canaliculocele was performed. Physical examination revealed a 3 cm diameter, subcutaneous mass beneath the medial canthus of the right eye, with a defect in the maxillary bone below. Dacryocystorhinography demonstrated blockage at the level of the nasolacrimal duct. Fine needle aspiration confirmed the cavitary nature of the lesion. During rhinoendoscopy, a mass containing watery fluid was found. Following marsupialisation with a large mass wall resection, the lacrimal drainage system irrigated freely in the nasal chamber. The communication of the lumen of the diverticulum with the lumen of the superior but not the inferior canaliculus was clearly demonstrated during endoscopy. Given negative immunohistochemical staining for smooth muscle actin and desmin, nasolacrimal dacryocele appears to be the most likely diagnosis. Histological examination confirmed that no goblet cells were present in the wall of the diverticulum, which is consistent with the canaliculus rather than the lacrimal sac. Complete resolution was observed without recurrence one year after surgery. Despite its rarity, a canaliculocele should be considered in adult dogs with nasolacrimal duct obstruction. Marsupialisation seems to be the appropriate therapy.     

Acquired extrahepatic portosystemic shunts in a young dog

A young, male miniature poodle was presented with severe neurological problems. Laboratory tests and ultrasonograph examination were consistent with extrahepatic portosystemic shunts, resulting in hepatic encephalopathy. When surgical correction proved not to be a viable option, the dog was euthanized. Postmortem examination revealed multiple shunts likely acquired after severe hepatitis.     

Acquired scoliosis associated with hydromyelia and syringomyelia in two dogs

Progressive scoliosis resulting from hydromyelia and syringomyelia was found in 2 dogs. In one dog, hydromyelia was associated with pachymeningeal fibrosis, with adhesions in the cervical portion of the spinal cord. In the other case, a cause was not established. Neither dog had congenital CNS malformations. The clinicopathologic findings in the 2 dogs are described, and the etiology and pathogenesis of hydromyelia and syringomyelia are discussed.     

Acquired myasthenia gravis and cholangiocellular carcinoma in a dog

Acquired myasthenia gravis and cholangiocellular carcinoma were diagnosed in a 7-year-old English Setter referred because of forelimb lameness, exercise-induced weakness, and fever. Three months earlier, the dog had had a pleuropulmonary infection caused by a Fusobacterium sp. The concurrent development of myasthenia gravis and cholangiocellular carcinoma in this dog may be explained by a paraneoplastic syndrome, although it is unproven. The cholangiocellular carcinoma may have possessed an acetylcholine receptor-like antigen on the tumor surface, which induced autoantibodies to cross-react with acetylcholine receptors at the neuromuscular junction.     

Acquired nephrogenic diabetes insipidus in a dog with leptospirosis

A 5 year old male neutered Cairn Terrier was evaluated for signs of polyuria and polydipsia. Initial hematology and chemistry panels were unremarkable and urinalysis showed a persistent hyposthenuria. Eleven days later, the dog became lethargic, inappetent and had developed acute renal failure. The dog was ultimately euthanized due to a poor response to treatment. Microscopic agglutination titres were consistent with a diagnosis of leptospirosis. The initial hyposthenuria in this case was consistent with acquired nephrogenic diabetes insipidus. This is an uncommon presentation of leptospirosis that has not previously been described to progress to acute renal failure. Leptospirosis should be considered as a differential diagnosis in any dog presenting with polyuria and polydipsia and these patients should be treated as a zoonotic risk.     

Acquired cardiac diseases in the dog: a retrospective analysis

To document the frequency of the different acquired cardiac diseases in the referring area of the University of Zurich, records of 474 dogs were retrospectively analysed. Most common were valvular diseases, predominantly atrioventricular valve endocardiosis (49.4%), myocardial diseases, predominantly dilated cardiomyopathy (21.1%), pericardial effusion (12.4%), mainly due to neoplasia or idiopathic pericarditis, and cardiac neoplasia without pericardial effusion (7.0%). Rare to very rare diagnoses were dirofilariosis (2.5%), endocarditis (1.1%, only 2 of these valvular), hypertrophic cardiomyopathy (0.6%) and infectious pericarditis (0.4%). Arrhythmias were found in 145 dogs, mainly tachyarrhythmias, and most commonly associated with dilated cardiomyopathy. Relevant concomitant diseases were tracheobronchial collapse and hyperadrenocorticism in dogs with mitral endocardiosis. Knowing prevalence and causes of the various cardiac and the complicating non-cardiac diseases with clinical similarities is important for formulating diagnosis and differential diagnosis.     

Acquired myasthenia gravis associated with oral sarcoma in a dog

Acquired myasthenia gravis is a common neuromuscular disorder resulting from autoantibody directed against the post-synaptic acetylcholine nicotinic receptors in skeletal muscle. Myasthenia gravis has been reported previously as a paraneoplastic syndrome. This case report presents myasthenia gravis secondary to an oral sarcoma in a juvenile Mastiffdog.     

Acquired hyposegmentation of granulocytes (pseudo-Pelger-Hu?t anomaly) in a dog.

Hyposegmentation of granulocyte nuclei was diagnosed in an adult dog after unsuccessful attempt at finding an occult chronic infection. Intermittent signs of prostatitis were temporarily observed, but the immature nature of circulating granulocytes persisted nine months. Electron microscopic examination and neutrophil function studies revealed no abnormalities. Since previous blood smear evaluation had been normal, it is proposed that the granulocyte anomaly was acquired and may have resulted from an idiosyncratic reaction to one of several chemotherapeutic agents administered.     

Acquired myasthenia gravis associated with a non-invasive thymic carcinoma in a dog

An 8 1/2-year-old neutered male Beagle was diagnosed with acquired myasthenia gravis associated with a non-invasive thymic carcinoma. The thymic mass was surgically excised and the dog was treated with pyridostigmine, prednisolone and azathioprine. Serial acetylcholine receptor antibody titres were increased initially but slowly declined to normal values over a period of 24 weeks. Improved exercise tolerance was seen following therapy, however, oesophageal dysfunction persisted. The dog was euthanased 26 weeks after initial presentation due to a complicating illness. A necropsy showed no regrowth or metastasis of the thymic carcinoma.     

Hydrocephalus and syringomyelia in a cat.

A 3-month-old male Japanese cat with feline parvovirus infection, showing central and cervical nerve abnormalities, was diagnosed as hydrocephalus and syringomyelia by use of magnetic resonance imaging (MRI). The cat was maintained clinically by medical treatment even though he could not stand. The MRI scans obtained about 5 months later showed that the ventricles had increased in size and the cervical syrinx had extended into the thoracic spinal cord. Ventriculoperitoneal (VP) shunt was performed. One week after surgery, neurological conditions had improved. At the postoperative MR images, the ventricles had decreased in size and the syrinx in the cervical and thoracic spinal cord could no longer be seen. The cat was still alive and was able to walk well.     

Acquired caudal vena cava occlusion and high protein ascites in a dog

High protein ascites developed following acquired obstruction of the vena cava in a dog. The cause of the obstruction was fibrosis associated with migration of a foreign body to the area. Diagnosis was made by venography and biochemical and cytological assessment of the ascitic fluid. The dog responded to surgical resection of the fibrous tissue and removal of the foreign body, a needle.     

Acquired arteriovenous fistula in a dog following perivascular injection of thiopentone sodium

An acquired arteriovenous fistula between the distal collateral radial and median arteries arising from the brachial artery, and the cephalic, brachial and median cubital veins of the right foreleg in an 8-year-old Afghan Hound is described. The arteriovenous fistula was apparently acquired two years previously after a perivascular injection of the anaesthetic agent thiopentone sodium in 5 per cent W/V solution* and was found as an incidental problem during an examination for an unrelated lameness problem. The arteriovenous fistula was characterized by a large pulsatile swelling that had a continuous thrill and bruit. A positive Branham sign was present. The lesion was diagnosed by physical and radiological examination. Ligation of the brachial artery has provided some post-operative improvement in exercise tolerance.     

Acquired bilateral laryngeal paralysis associated with systemic lupus erythematosus in a dog

A 4 yr old spayed female Labrador retriever was referred for acute respiratory distress and was found to have bilateral laryngeal paralysis. Physical examination and biochemical testing were consistent with systemic lupus erythematosus (SLE) and did not reveal a likely alternative cause for the laryngeal paralysis. Following immunosuppressive and supportive treatment, the dog regained normal laryngeal function. At a scheduled follow-up examination 6 wk later, normal laryngeal function was confirmed via sedated laryngeal examination. Laryngeal paralysis associated with SLE has been reported in humans, but this is the first known report of acquired laryngeal paralysis associated with SLE in the dog.     

Application of ventriculoperitoneal shunt as a treatment for hydrocephalus in a dog with syringomyelia and Chiari I malformation

A twenty-month-old Chihuahua male dog was presented to us suffering with ataxia. Based on the physical examination, X-ray and magnetic resonance imaging (MRI) examinations, we diagnosed the dog with hydrocephalus, Chiari I malformation and syringomyelia. Treatment consisted of internal medical treatment and the placement of a ventriculoperitoneal (VP) shunt. The ventricular dilatation was relieved and the dog improved neurologically; however, the Chiari I malformation and syringomyelia remained after surgically positioning the VP shunt.