Intracranial meningioma with pulmonary metastasis in three dogs.

Extracranial metastasis of primary central nervous system neoplasms is uncommon and has not been described in the dog. We report the clincopathologic features of intracranial meningioma with pulmonary metastasis in three dogs (case No. 1: 13-year-old castrated male Boxer dog; case No. 2: 14-year-old spayed female Dachshund; case No. 3: 6-year-old spayed female German Shepherd Dog). Case No. 1 presented with ataxia, lethargy, vomiting, and leaning and falling to the right, and had a transient remission following radiation and corticosteroid therapy; case No. 2 had a history of seizures that were unresponsive to primidone, left-sided postural reaction deficits, ataxia, and circling to the right; case No. 3 had only intermittent episodes of vomiting Computed tomography of case Nos. 1 and 2 revealed peripherally located homogeneous contrast-enhancing intracranial masses. Postmortem examination revealed intracranial masses with single or multiple pulmonary nodules in all three cases. Histologically, the intracranial and pulmonary masses were meningotheliomatous meningiomas with atypical features including brain infiltration, necrosis, nuclear atypia, prominent nucleoli, and moderate cell density. All of the primary meningiomas had low mitotic rates. The current interest in early diagnosis and aggressive clinical/surgical management of canine patients with meningioma and other primary central nervous system neoplasms will likely result in an increased detection of extracranial metastases.     

Intracranial dermoid cyst in a dog

A 7-year-old spayed bitch had a 3-year history of episodes of hind-limb weakness and ataxia. Neurologic abnormalities consisted of deficits in postural reactions, spinal reflexes, and conscious proprioception. A right-sided head tilt also was observed. Immediately after cervical radiography, CSF tap, and electroencephalography, the dog was alert, but it was found comatose the next morning and died within an hour. At necropsy, a 1.6- x 0.8- x 1.5-cm, thinly encapsulated mass was found on the left cerebellar peduncle. It had caused dorsal displacement of the left portion of the cerebellum and ventral compression of the fourth ventricle. Histologically, the mass was determined to be a dermoid cyst.     

Necrotising encephalitis in a French bulldog

A 20-month-old, female French bulldog was presented with a three-month history of generalised seizures and progressive ataxia with occasional falling over on either side. Neurological examination revealed signs, suggesting a multifocal intracranial lesion. Magnetic resonance imaging of the brain revealed two connected lesions on the left side of the caudal brainstem and a further lesion in the cerebrum. The dog was euthanased, and histopathological examination revealed lesions which closely resembled those of necrotising encephalitis in Yorkshire terriers. This is the first case describing this type of necrotising encephalitis in a French bulldog.     

Sequential magnetic resonance imaging changes after suspected global brain ischaemia in a dog

Sequential magnetic resonance imaging studies over a period of 18 months were performed in a two-year-old pug dog after suspected global brain ischaemia following an anaesthetic accident. The dog was presented with seizures and neurological deficits consistent with a left brainstem and multifocal/diffuse forebrain lesion after an asymptomatic interval of 72 hours following the ischaemic event. Magnetic resonance imaging scans were performed three hours, six weeks, seven and 18 months after the incident. In the acute stage, signal hyperintensity was evident in the occipital and parietal regions of the cerebral cortex and in both rostral caudate nuclei. Slight involvement of the white matter was also noticed. In the chronic phase, the signal hyperintensity in the affected areas of the cortex was diminished and smaller in size, whereas the white matter did not appear to be compromised anymore.     

Toxic effects of cyclonite (C‐4) plastic explosive ingestion in a dog

Objective – To describe the clinical manifestations following cyclonite (C‐4) plastic explosive ingestion in a dog. Case Summary – A 2‐year‐old male castrated Labrador working dog weighing 35 kg was presented for seizures shortly after ingestion of C‐4. The dog was successfully treated for the seizures, but developed polyuria/polydipsia shortly after being discharged and was ultimately diagnosed with chronic kidney disease. New or Unique Information Provided – This is the first documented case of renal insufficiency in a dog after C‐4 intoxication.     

Disseminated protothecosis diagnosed by evaluation of CSF in a dog

A 5-year-old female spayed Shetland Sheepdog Mix dog was evaluated for a history of recent seizure activity, progressive hind limb ataxia, polyuria, and polydipsia and no history of gastrointestinal signs. Physical examination findings included conscious proprioceptive deficits, ataxia, and anterior uveitis along with a hypermature cataract in the right eye. Results of a CBC, serum biochemical profile, urinalysis, and computed tomography scan of the brain were unremarkable. Cerebrospinal fluid (CSF) analysis revealed marked eosinophilic pleocytosis and rare organisms consistent with Prototheca spp within neutrophils and macrophages. On postmortem histologic examination, mononuclear inflammation and numerous intralesional algal organisms, similar to those seen on the cytologic preparation of CSF, were found in the brain, eyes, kidneys, and heart. Abnormalities were not detected on gross and histologic examination of the gastrointestinal tract. Cultures of CSF and subdural/olfactory bulb, but not intestinal tract, yielded growth of Prototheca spp, and PCR analysis and DNA sequencing confirmed the organism as Prototheca zopfii genotype 2. We have reported a rare case of disseminated protothecosis that was diagnosed by evaluation of CSF in a dog presented with neurologic signs and no overt enteric disease. Protothecosis should be considered as a rare cause of seizures, even in the absence of obvious enteric signs, and should be included in the differential diagnosis of eosinophilic pleocytosis.     

Colonic,ureteral, and vascular injuries secondary to stick impalement in a dog

Objective – To report the surgical repair, case management, and outcome of a dog with sepsis and severe intraabdominal trauma secondary to a penetrating stick injury. Case or Series Summary – A 1.5‐year‐old, spayed female, mixed‐breed dog was presented to the emergency service after incurring a small laceration on the medial aspect of the left pelvic limb while running in the woods. The wound was surgically explored and a primary closure achieved. The patient was discharged the same day with oral antimicrobial therapy. The following morning the dog was represented to the emergency service for acute vomiting. Abdominal radiographs were performed and demonstrated loss of serosal detail and pneumoperitoneum. An emergency celiotomy was performed and revealed distal colonic perforation, left ureteral laceration, and lacerations of the left common iliac vein. Ureteronephrectomy, as well as primary closure of the distal colonic perforation and left common iliac vein lacerations, were performed. The patient recovered and was ultimately discharged from the hospital 5 days later. Follow‐up 1 year later revealed no significant physical exam or biochemical abnormalities. New or Unique Information Provided – A seemingly benign penetrating stick injury initially deemed to be superficial in nature was later demonstrated to have resulted in sepsis following severe intraabdominal trauma that included lacerations of the distal colon, left ureter, and left common iliac vein in a dog. Successful surgical management and intensive care led to a full recovery without any residual impairment noted a year later.     

Exophthalmos due to sterile neutrophilic dermatosis in a dog

An 8‐year‐old castrated male Bichon Frise was presented to the Kansas State University Veterinary Health Center for evaluation of unilateral right‐sided exophthalmos, suspected secondary to a retrobulbar abscess. The dog had acutely developed right‐sided periorbital swelling, exophthalmos with pain on retropulsion, as well as multiple cutaneous exudative plaques on the feet and tail base. On ophthalmic examination, the dog also exhibited mild left‐sided exophthalmos with decreased, nonpainful retropulsion. Orbital ultrasound and CT were performed to evaluate the extent of bilateral orbital disease. Incisional biopsies were obtained from the affected right periorbital tissues and skin of the feet, and histopathology revealed severe neutrophilic inflammation of the dermis with no organisms detected. Histologic changes were consistent with sterile neutrophilic dermatosis. The dog achieved clinical remission following treatment with initial immunosuppressive doses of corticosteroids and subsequent long‐term maintenance therapy using oral cyclosporine.     

Severe seizures associated with traumatic brain injury managed by controlled hypothermia,pharmacologic coma,and mechanical ventilation in a dog

Objective – To describe the management and outcome of a dog presenting with intractable seizures associated with traumatic brain injury. Case Summary – A spayed female Wheaten Terrier was presented to an emergency clinic with neurologic deficits (modified Glasgow coma scale of 10) shortly after a road traffic accident. Seizures were uncontrolled despite aggressive pharmacologic intervention. Controlled hypothermia to achieve a rectal temperature of 33–35°C (91.4–95°F) was initiated as a protective measure to reduce intracranial pressure and cerebral metabolic rate, and to assist with seizure control. Intubation and mechanical ventilation were required to protect the airway and manage hypercapnia associated with hypoventilation. The patient went on to make a full recovery, although behavioral changes were noted by the owners for an 8‐week period following injury. New or Unique Information Provided – To the author's knowledge, this is the first instance of therapeutic hypothermia reported in the veterinary literature. A short review of this treatment modality is provided.     

Brain abscess in seven cats due to a bite wound: MRI findings, surgical management and outcome

PRESENTATION AND LESION LOCALISATION: Seven adult domestic shorthair cats were presented with a 1- to 6-day history of progressive neurological signs. A focal skin puncture and subcutaneous swelling over the dorsal part of the head were detected on physical examination. Neurological examination indicated lesion(s) in the right forebrain in four cats, multifocal forebrain in one cat, left forebrain in one cat, and multifocal forebrain and brainstem in the remaining cat. In all cats, magnetic resonance imaging revealed a space-occupying forebrain lesion causing a severe mass effect on adjacent brain parenchyma. CLINICAL APPROACH AND OUTCOME: All cats were managed with a combination of medical and surgical treatment. At surgery a small penetrating calvarial fracture was detected in all cats, and a tooth fragment was found within the content of the abscess in two cats. The combination of surgical intervention, intensive care and intravenous antimicrobials led to a return to normal neurological function in five cats. PRACTICAL RELEVANCE: As this series of cases indicates, successful resolution of a brain abscess due to a bite injury depends on early recognition and combined used of antimicrobials and surgical intervention. A particular aim of surgery is to remove any skull and foreign body (tooth) fragments that may represent a continuing focus of infection.     

Combined interventional procedure and cardiopulmonary bypass surgery in a dog with cor triatriatum dexter,patent foramen ovale,and pulmonary stenosis

A 2‐year‐old American Pit Bull dog was presented for surgical evaluation of imperforate cor triatriatum dexter (CTD) and patent foramen ovale (PFO). Echocardiography identified an imperforate CTD associated with a right‐to‐left shunting PFO and valvular pulmonary stenosis. A 2‐step interventional and surgical approach was used. Initially, a pulmonary balloon valvuloplasty was performed, and subsequently the dog underwent a surgical correction of the atrial anomaly under cardiopulmonary bypass.     

Use of a titanium mesh for cranioplasty following radical rostrotentorial craniectomy to remove an ossifying fibroma in a dog

CASE DESCRIPTION: A 6-year-old Australian Terrier was evaluated for surgical removal of an ossifying fibroma of the left calvarium of 7 months' duration. CLINICAL FINDINGS: Computed tomography revealed invasion of the mass through the left parietal bone and extension into the epidural space of the brain. TREATMENT AND OUTCOME: A left rostrotentorial and frontal bone craniectomy was performed, and the mass was removed, along with a 1-cm margin of grossly normal bone. Cranioplasty was performed with a combination of porcine submucosa, titanium mesh, and screws. The dog recovered from surgery without complications and was discharged 3 days later. The dog was followed up for 24 months after surgery and has remained clinically normal. CLINICAL RELEVANCE: Findings suggested that rostrotentorial craniectomy is a viable option for removal of benign tumors affecting the parietal bones in dogs. Reconstruction of the resulting defect in the calvarium is possible with a combination of porcine submucosa and rigid titanium mesh.     

Primary pulmonary adenocarcinoma metastatic to the uvea, brain and adrenal gland in a dog

A 10-year-old male Briard dog was presented because of listlessness, abnormal gait, fever, inappetence, and seizures. A non-pigmented growth was observed in the ventral quadrant of the left iris. Thoracic radiographs revealed multiple pulmonary metastases and the owner opted for killing. On necropsy, lung masses and nodules in left iris, right adrenal medulla, and brain were detected. Histologically the primary tumour was diagnosed as pulmonary adenocarcinoma with predominant solid pattern. Metastases to regional lymph nodes, uvea, adrenal medulla, and brain were recognized. The metastatic behaviour resembled that occurring in humans. To the authors' knowledge, this is the first report of a pulmonary adenocarcinoma with metastasis to the uvea in a dog.     

Gastrointestinal tract perforations caused by ingestion of multiple magnets in a dog

Objective – To describe a case of gastrointestinal tract perforation, septic peritonitis and coagulopathy caused by ingestion of multiple magnets in a dog. Case Summary – An 8‐month‐old castrated male Rottweiler, weighing 30.5 kg was presented for evaluation of vomiting and weakness. Abdominal radiography and abdominal ultrasonographic examination identified a metallic foreign object within the gastric lumen, presence of free peritoneal gas, and peritoneal effusion. Septic peritonitis was diagnosed by abdominal fluid analysis. Exploratory celiotomy revealed the presence of an omental abscess, and gastric and colonic perforations. Four magnetic foreign objects were found within the lumen of the perforated stomach. Surgical management including removal of the magnets, abscess debridement and excision, perforation repair, and abdominal drainage combined with intensive medical therapy resulted in complete recovery of this dog. New or Unique Information Provided – This report describes in detail the case management of a dog that developed both gastric and colonic perforations and severe morbidity secondary to ingesting multiple magnets.     

Brain and ocular metastases from a transmissible venereal tumour in a dog

A five-year-old crossbred dog was referred with rapidly growing masses over its penis and right popliteal lymph node. The dog had severe blepharospasm, congestion of episcleral vessels and rubeosis iridis of the left eye. A presumptive diagnosis of transmissible venereal tumour (TVT) and iridocyclitis was made based on the results of fine needle aspiration. Chemotherapy with vincristine and prednisolone was initiated and after four months the dog made a complete recovery. However, the dog subsequently relapsed, showing miosis, blepharospasm and a well defined mass within the anterior chamber of the left eye. In addition, the dog exhibited generalised 'grand mal' type seizures. Computed tomographic (CT) examination of the brain revealed two distinct masses in the left frontal lobe. Because of the poor prognosis, the owners elected to have the dog euthanased. On histopathology, metastases of TVT in the left eye and left cerebral hemisphere were found, showing no specific staining for CD3, immunoglobulin (Ig) G, IgM and lambda light chains. It was therefore concluded that the tumour growth was progressive, and that there was an absence of local humoral immune response against TVT in this case.     

Late Abscess Formation Caused by Silk Suture Following Hysterectomy in a Female Dog

A 5‐year‐old female cross‐breed dog was presented for a one‐month history of lethargy, poor appetite and weight loss. A hysterectomy had been performed 2 years ago. Abdominal palpation revealed a mid‐abdominal mass and haematological analysis showed leucocytosis with left shift. On abdominal radiographs, a 9 cm in diameter soft tissue opacity mass ventral to the colon and caudal to the left kidney was observed. The abdominal ultrasonography revealed a mass well circumscribed, with a hyperechoic capsule and hypoechoic center with echoic debris. The presumptive diagnosis was an abscess due to foreign body granuloma. Laparotomy was performed and a mass close to the left ovary was found. Adhesions and residues of the suture material were observed close to the right ovary and the uterine body stump. The mass, both ovaries and adhesions were removed. On cut section of the mass two cavities were observed. The small one contained three embedded silk suture residues. Histopathological examination confirmed the diagnosis of a chronic abscess caused by silk suture.     

Magnetic resonance imaging findings in Finnish Spitz dogs with focal epilepsy

Eleven Finnish Spitz dogs with focal seizures and 3 healthy controls were evaluated. General clinical and neurological examinations, blood examination, urinalysis, cerebrospinal fluid examination, electroencephalography (EEG), and magnetic resonance imaging (MRI) of the brain were performed on all dogs. On EEG examination, focal epileptic activity was found in 7 of 11 dogs (64%), and generalized epileptic activity was observed in 4 of 11 dogs (36%). MRI (performed with 1.5 T equipment) detected changes in 1 epileptic dog. Mild contrast enhancement after gadolinium injection was identified in this dog's right parietal cortex. However, no such changes were observed in repeated magnetic resonance images. Special emphasis was given to seizure history to determine any correlations between seizure intervals and MRI findings. Our results indicate that Finnish Spitz dogs with focal seizures suffer from focal idiopathic epilepsy and have nondetectable findings on MRI or pathology. MRI showed poor sensitivity in detecting epileptogenic areas in our patients with focal seizures. Reversible MRI changes in 1 dog could have been caused by seizures.     

Necrotizing meningoencephalitis associated with cortical hippocampal hamartia in a Pekingese dog

A 4-year-old male Pekingese dog was referred to the clinic with a history of recurrent seizures and progressive abnormal gait and behavior, which did not respond to treatment. At necropsy, a large cortical defect in the right temporo-parietal cortex, malacia of subcortical white matter, right basal nuclei, and capsula interna, as well as abnormalities of the right hippocampus were observed. Histological examination of the brain revealed moderate to severe nonsuppurative meningoencephalitis in the left cerebral hemisphere and extensive infarction-like lesions with milder inflammation in the right hemisphere. In the right hippocampus, the pyramidal cells were arranged in a gyrus-like pattern and intermingled with gemistocytic and fibrillary astrocytes. The histopathological features of the inflammatory lesions were consistent with necrotizing meningoencephalitis and resembled those described in so-called Pug dog encephalitis. The hippocampal changes were interpreted as dysplasia (monolateral hippocampal cortical hamartia), unrelated to clinical signs and necrotizing inflammatory lesions.     

Presumptive hepatotoxicity and rhabdomyolysis secondary to phenazopyridine toxicity in a dog

Objective – To describe a rare, but potential clinical manifestation of phenazopyridine (PAP) toxicity in a dog. Case Summary – A 6‐year‐old spayed female Chihuahua was evaluated for ataxia and dysphagia after ingestion of 200 mg (66 mg/kg) of PAP hydrochloride. The dog was presented to the hospital with shifting leg lameness involving all 4 limbs, which progressed to reluctance to walk and severe diffuse muscle hyperesthesia. Clinical laboratory abnormalities included marked increases in serum alanine aminotransferase, aspartate aminotransferase, creatine kinase, mild increases in alkaline phosphatase, and increased c‐Tnl‐troponin concentration. Treatment included administration of intravenous fluids, muscle relaxants, pain medications, and hepatoprotectants for 5 days in the hospital, and medical management at home for an additional 5 days. Follow‐up examinations performed 1 and 6 months after initial presentation revealed the dog to be clinically healthy with serum biochemical profiles within reference intervals. New or Unique Information Provided – The purpose of this report is to describe an unusual manifestation of PAP toxicosis in a dog, which has not been previously reported in the literature. A review of the ASPCA Animal Poison Control Center database revealed 347 cases of PAP exposure in dogs during 2000–2009 underscoring the importance of being aware of this toxicity in the dog.     

Brain abscess and bacterial endocarditis in a Kerry Blue Terrier with a history of immune-mediated thrombocytopenia

Objective: To describe a case of multifocal brain abscessation as a sequela from bacterial endocarditis in a dog with a 4‐month history of immune‐mediated thrombocytopenia (ITP) and treatment with immunosuppressive therapies. Case summary: An 8‐year‐old spayed female Kerry Blue Terrier weighing 13 kg was presented for evaluation of progressive neurologic deficits after a 4‐month history of immunosuppressive treatment of ITP. Brain magnetic resonance imaging revealed lesions consistent with multiple central nervous system abscesses and rupture of an abscess into an adjacent ventricle. Staphylococcus species were cultured from blood and cerebral spinal fluid and a vegetative lesion of the mitral valve was identified by echocardiographic examination. Intensive care, intravenous antibiotics, and supportive therapy led to resolution of clinical signs. Resolution of the vegetative lesion on the mitral valve was documented by serial echocardiographic examination. The dog was clinically normal 11 months after treatment. New or unique information provided: Bacterial endocarditis can be an occult infection and difficult to diagnose. Emboli from endocarditis are common, but those that affect the spleen and kidneys are often clinically silent in dogs. This case represents the first report of multifocal brain abscessation (documented with magnetic resonance imaging) as a sequela from bacterial endocarditis.