A retrospective study of 19 cases of canine myelofibrosis

Nineteen cases of myelofibrosis were identified among 456 canine bone marrow specimens submitted for analysis. Myelofibrosis was classified as primary in I dog and as secondary in 18 dogs. Clinical conditions associated with secondary myelofibrosis included immune-mediated hemolytic anemia (n = 5), neoplasia (n = 4), and long-term drug treatment (n = 4). Drugs administered included phenobarbital, phenytoin, phenylbutazone, and colchicine. Bone marrow necrosis was observed in 5 dogs. Eight dogs were treated with immunosuppressive doses of prednisolone, and 3 were treated with erythropoietin. Half of the dogs with secondary myelofibrosis recovered from their cytopenias and were alive from 4 months to 5 years after diagnosis.     

Chronic canine ehrlichiosis (Ehrlichia canis): a retrospective study of 19 natural cases

Nineteen dogs from Greece with chronic ehrlichiosis were studied. The dogs exhibited bicytopenia or pancytopenia, bone marrow hypoplasia, seroreactivity to Ehrlichia canis (E. canis) antigens, and had no history of drug or radiation exposure. Anorexia, depression, severe bleeding tendencies, hypoalbuminemia, and increased serum alanine aminotransferase activity were also hallmarks of the disease. All these animals eventually died, irrespective of the treatment applied. Some dogs were also serologically positive for Rickettsia conorii, Leishmania infantum (L. infantum), and Bartonella vinsonii subspp. berkhoffii. Polymerase chain reaction testing of bone marrow samples revealed E. canis, Anaplasma phagocytophilia, Anaplasma platys, and L. infantum in some dogs. Concurrent infections did not appear to substantially influence the clinical course and final outcome of the chronic canine ehrlichiosis.     

Histopathologic features of canine uremic gastropathy: a retrospective study

Uremic gastritis is a term commonly used to describe the gastrointestinal signs and histopathologic changes associated with renal failure in the dog. This retrospective study reviews the clinical, serum biochemical, and postmortem histopathologic data from 28 dogs with renal failure to determine the prevalence of gastric histopathology, characterize the gastric histopathology, and identify associations between gastric histopathology and serum concentrations of blood urea nitrogen (BUN), creatinine (Cr), calcium-phosphorus product (Ca x Phos), and hematocrit. Affected and control dogs with available renal and gastric tissue, serum biochemistry data, and urinalysis data were identified over a 10-year period (1992-2002) in the pathology department postmortem examination database at the Cornell University College of Veterinary Medicine. The serum biochemistry data and histopathologic findings were scored as normal, mild, moderate, and severe. All affected dogs had derangements of BUN, Cr, or Ca x Phos with gastric histopathology in 22 of 28 dogs (79%). Dogs with renal failure had a higher prevalence of gastric histopathologic changes compared with the control group. Associated histopathologic changes in the stomach were edema (P = .008), mineralization (P = .03), and vasculopathy (P = .03). Only 1 dog had evidence of gastric ulceration. Gastric necrosis was an uncommon finding (4/28, 14%). Gastric histopathology appears to be common in dogs with renal failure and is associated with increasing severity in the serum biochemistry data. Unlike humans with renal failure, in whom gastric ulceration predominates, gastric necrosis and ulceration appear to be uncommon in dogs with renal failure.     

Cytological grading of canine cutaneous mast cell tumours

A cytological grading for mast cell tumours (MCTs) would be highly desirable, allowing to select the most appropriate therapeutic intervention prior to surgery. This study evaluates the applicability on fine‐needle aspirations (FNAs) of the novel Kiupel grading system, based on number of mitoses, multinucleated cells, bizarre nuclei and presence of karyomegaly. Fifty consecutive cases with pre‐operative cytological diagnosis were included. In cytological specimens, approximately 1000 cells were evaluated, and the histological grade was assessed on the corresponding resected specimens. On cytology, the above parameters were significantly different between histologically low‐grade and high‐grade tumours (P < 0.001). The cytograding correctly predicted the histological grade in 47 cases (accuracy, 94%; sensitivity, 84.6%; specificity, 97.3%). Two high‐grade MCTs (4%) were not detected on cytology. The cytograding can provide helpful insights to assist clinical decisions in most cases. However, the risk of underestimation in a minority of patients represents a limit to the overall utility of the technique.     

Aetiology of canine otitis externa: a retrospective study of 100 cases

The objective of this retrospective study was to investigate in 100 dogs with otitis externa (OE) the possible associations between signalment, history, clinical and laboratory findings and the various primary, secondary and perpetuating causative factors of ear canal inflammation. The age of the dogs ranged from 3 months to 14 years (median: 4.75 years) and they included 45 males and 55 females. Cocker spaniels, Jura des Alpes and Brittany spaniels were significantly overrepresented among dogs with OE when compared to the hospital canine population. In the majority of the cases, OE was chronic-recurrent (63%) or bilateral (93%). Allergic dermatitis (43/100 dogs), grass awns (12/100) and otoacariasis (7/100) were the most common primary causative factors; no primary factor could be incriminated in 32 cases and more than one was found in three dogs. Malassezia spp. (66/100 dogs), cocci (38/100) and rods (22/100) were the secondary causative factors, while ear canal stenosis (38/100) and tympanic membrane perforation-otitis media (25/100) were the most important perpetuating factors. Atopic dermatitis and adverse food reactions-associated OE was more common in females and dogs with a history of pruritic skin disease, while grass awn-induced OE occurred in cocker spaniels and acute cases. Tympanic membrane perforation was less frequent in atopic dermatitis and adverse food reactions-associated OE, but more common when otoscopic and ear canal cytological examination revealed the presence of grass awns and rods, respectively. Finally, cocci overgrowth was positively associated with ear canal stenosis.     

Salivary gland necrosis in dogs: a retrospective study of 19 cases

Salivary gland necrosis has been described in dogs and is characterised by enlarged, hard, painful salivary glands, retching and vomition or regurgitation. The cause has yet to be determined. A retrospective study of 19 dogs with the same clinical signs was undertaken for breed, age, gender, history and presenting signs, diagnostic evaluations and findings, treatment and outcome. An underlying association was identified in 16 of the 19 dogs. This included Spirocerca lupi infestation (seven dogs), megaoesophagus (three dogs) and oesophagitis, oesophageal diverticulum, giardiasis and suspected autoimmune sialadenitis. Almost all associated lesions involved the oesophagus. Where the associated disease was successfully treated, the salivary glands returned to normal and all clinical signs resolved. It is hypothesised that an afferent vagal reflex may be involved, and that the mechanism of disease is similar to the neural pathogenesis suggested for hypertrophic osteopathy; in this instance, the efferent targets are the salivary glands rather than the limbs.     

Insulin-secreting tumours of the canine pancreas: Clinical and pathological features of 11 cases

This paper describes the clinical and pathological features of 11 dogs with insulin-secreting tumours of the pancreas. All the dogs showed episodic weakness or collapse. The diagnosis was made on fasting plasma glucose and serum insulin concentrations, the insulimglucose ratio, and the results of an intravenous glucose tolerance test. Ten of the dogs had exploratory laparotomy, and partial pancreatectomy was performed in nine of the cases. One case was euthanased at surgery because of widespread metastases. The tumours were graded histologically and the results compared with the time to recurrence of clinical signs and postoperative survival time. Postoperative survival time for dogs which died or were euthanased as a direct result of tumour recurrence, and time to recurrence of clinical signs were calculated from actuarial survival curves. The median time to recurrence of clinical signs after surgery was 12 months (range from four to 16 months; mean time to recurrence of clinical signs 12 months). Two cases died of unrelated disease, without recurrence of hypoglycaemic signs. The median postoperative survival time was 14 months (range 10 to 33 months; mean survival time 15 months). There is a suggestion that tumours with a high mitotic count carried a worse prognosis.     

Distinctive histopathologic features of canine optic nerve hypoplasia and aplasia: a retrospective review of 13 cases

Canine optic nerve hypoplasia (ONH) and aplasia (ONA) are significant neuro-ophthalmologic disorders that have been reported in several species. The purpose of this study was to describe the distinctive histopathologic features of ONH and ONA in canine patients identified from a collection of 20 000 ocular submissions at the comparative ocular pathology laboratory of Wisconsin from 1989 to 2006. The following information about ONH and ONA cases was collected: signalment, and clinical and gross findings, including unilateral vs. bilateral involvement. Microscopic evaluation was performed, with attention to optic nerve malformation, retinal ganglion cell (RGC) and nerve fiber layer (NFL) loss, and retinal disorganization. The distribution of retinal vasculature was recorded and a search for unusual findings of ONH and ONA was performed. Information and histologic documentation was available for 13 cases. Eight cases of ONH and five cases of ONA were identified. The average group age was 20.2 months and 16.1 months, respectively. The most common breed was the Shih Tzu (3/13). ONH usually presented bilaterally (7/8); all ONA cases presented as a unilateral disease (5/5). The morphologic findings in the optic nerve (ON) in ONH included variable degrees of ON hypoplasia and gliosis, as well as ectopic vestigial ON remnants within orbital nerves and connective tissues. The NFL was detected in the majority of the ONH cases; however, RGCs were rare or absent. Mild retinal disorganization was seen occasionally. Most cases of ONH were associated with regional peripheral retinal blood vessel extension into the vitreous, leaving the peripheral retina avascular. In ONA cases the retinal blood vessels, NFL and RGCs were totally absent and retinal disorganization was severe. Distinctive microscopic features encountered in ONA included anterior segment dysgenesis in some cases. The retina in these cases was stretched across the posterior lens capsule, never making contact with the posterior pole of the globe. The current study reviews the human and veterinary literature pertaining to ONH and ONA, compares ONH and ONA in dogs, and presents related ophthalmic histopathologic findings that have not been reported previously.     

Pre-operative neoadjuvant vinblastine-prednisolone in canine mast cell tumours: A single-centre retrospective cohort study

Neoadjuvant chemotherapy can be used in canine mast cell tumours (MCTs) to optimise surgical margins or to enable marginal excision in challenging locations. The objective of this study was to describe the outcome of dogs with cutaneous and subcutaneous MCTs treated with neoadjuvant vinblastine-prednisolone (NA-VP). Records of treatment-naïve dogs with cutaneous/subcutaneous MCT that received NA-VP were reviewed including signalment, indication for NA-VP, staging results, clinical response, surgical data and histopathology reports. For dogs with post-operative follow-up ≥365 days, predictive factors for local recurrence (LR) were evaluated. Forty-four dogs were included. NA-VP was indicated to optimise surgical margins (group MARG) in 19 dogs (43.2%) and to enable surgery (group MORB) in 25 dogs (56.8%). Complete and partial response were documented in 40.9% of dogs and 30 dogs (68.2%) underwent surgery. The indication for NA-VP was significantly associated with undergoing surgery (p < .001) on multivariable analysis. Twelve (48%) and 18 dogs (94.7%) underwent surgery in the group MORB and MARG, respectively. Five dogs (16.7%) experienced wound dehiscence. Complete excision was achieved in 14 dogs (46.7%). In dogs undergoing surgery with ≥365 days of follow-up, LR was documented in five cases (20.8%). None of the factors analysed including mitotic count, completeness of excision and response to NA-VP were associated with LR; notably, LR occurred in 3/11 (27.2%) completely excised MCTs. In a pre-operative setting, NA-VP appears safe and could be beneficial in selected cases. Prognostic factors such as clinical response, mitotic count and completeness of excision should be interpreted with caution following NA-VP.     

Primary thoracic wall tumours of mesenchymal origin in dogs: a retrospective study of 46 cases

Forty-three of the chest wall tumours in 46 dogs were malignant; five had metastases apparent at the time of presentation, five more had metastases discovered intraoperatively. Surgical resection of the tumours was associated with a significantly better outcome than conservative management. The median survival times after surgery for dogs with osteosarcoma was 17 weeks, for dogs with fibrosarcoma it was 26 weeks and for dogs with chondrosarcoma it was 250 weeks. En bloc excision of primary tumours affecting the chest wall was associated with minimal morbidity, but long-term survival was limited by distant metastases, primarily to the lungs. The tumours recurred in only three dogs. Early, radical surgical excision is recommended in the management of tumours of the chest wall. The prognosis depends on the histologic type of tumour and a histological diagnosis is mandatory before excision.     

Coarse fractionated radiation therapy for pituitary tumours in cats: a retrospective study of 12 cases

This retrospective study describes the clinical progression of 12 cats with pituitary tumours treated with a coarse fractionated radiation protocol delivering a total dose of 37 Gy in five once weekly fractions. A pituitary macrotumour was identified in all 12 cats: 4 with neurological signs only and 8 with insulin‐resistant diabetes mellitus secondary to acromegaly. One of the cats with central neurological signs died before completing the radiotherapy course; the remaining three had partial or complete remissions of their central neurological signs. Of the cats with unstable diabetes mellitus, five no longer required insulin therapy, one required less insulin and two became stable. The overall median survival time was 72.6 weeks; four cats died from related causes, two from unrelated problems and six remain alive. Radiation therapy is confirmed as an effective treatment for feline pituitary tumours, giving prolonged survival and control of both paraneoplastic and mass effect signs.     

Contrast radiographic findings in canine bacterial discospondylitis: a multicenter, retrospective study of 27 cases

A multicenter, retrospective study was undertaken to evaluate contrast radiographic findings in canine bacterial discospondylitis. Records and myelograms or epidurograms of 27 patients were obtained from five colleges of veterinary medicine. Fifteen cases (56%) were evaluated as having some degree of spinal cord compression. The majority (73.3%) of the cases had only soft tissue as the compressive mass. The median compression for all cases was 5% of the vertebral canal. No difference was noted for compression based on anatomical site (i.e., cervical versus thoracolumbar versus lumbosacral). No significant correlation between degree of lesion compression and clinical outcome was noted, but there was a trend toward increased mortality with greater compression. There was no correlation between the ambulatory status and the ultimate outcome. Three of the 15 (20%) cases showed vertebral subluxation. Results of this study indicate that static spinal cord compression is not a significant component of the neurological dysfunction associated with bacterial discospondylitis. Identification of vertebral subluxation in some patients may indicate a dynamic lesion that should be evaluated with stress radiography.     

Epidemiology and clinical significance of canine distichiasis: A retrospective study of 291 cases

Objective

To describe the epidemiological factors and clinical significance of canine distichiasis.

Animals studied

Two hundred and ninety-one client-owned dogs.

Methods

Retrospective study of medical records for canine patients diagnosed with distichiasis between 2010 and 2019 in an ophthalmology specialty practice. The breed, sex, skull conformation, coat type, age at the time of diagnosis, reason for presentation, clinical examination findings, and affected eyelid(s) were reviewed.

Results

The prevalence of distichiasis was 5.5% (95% confidence interval (CI): 4.9–6.1) in the population of dogs presented to an ophthalmology specialty practice. The breeds with the highest prevalence were English bulldogs (35.2%, 95% CI: 26.7–43.7) and American cocker spaniels (19.4%, 95% CI: 8.3–30.5). The prevalence was significantly higher in brachycephalic dogs (11.9%, 95% CI: 9.8–14.0) than in non-brachycephalic dogs (4.6%, 95% CI: 4.0–5.3) and in short-haired dogs (8.2%, 95% CI: 6.8–9.6) than in dogs with other coat types (5.3%, 95% CI: 4.5–6.1). Most dogs were affected bilaterally (63.6%, 95% CI: 58.0–69.1). Among dogs with clinical signs, 39.0% (95% CI: 26.5–51.4) exhibited corneal ulceration, including superficial ulcers (28.8%, 95% CI: 17.3–40.4) and deep stromal ulcers (10.2%, 95% CI: 2.5–17.8). Distichiasis was non-irritating in 85.0% (95% CI: 80.6–89.4) of affected dogs.

Conclusion

This study reports the largest cohort of canine distichiasis to date. In a large proportion of dogs, distichiasis was a non-irritating condition. However, brachycephalic breeds, especially English bulldogs, were the most frequently and severely affected.     

Localized tumours of the canine small intestine: a report of twenty cases

During a 10 year period. 20 dogs with primary localized neoplasia of the small intestine were presented at the University of Bristol Veterinary School. Half the tumours were carcinomas, the remainder being lymphosarcomas (5 cases), leiomyosarcomas (3 cases) and leiomyomas (2 cases) Lesions occurred at a variety of locations along the tract, but descending duodenum (6 cases) and terminal ileum (4 cases) were the commonest sites. Clinical findings varied. All dogs except three presented with chronic illnesses, but only seven showed signs immediately referable to alimentary tract disease. Abnormalities were found at radiographic examination in all cases except one and provided or confirmed the indication for laparotomy. Ten animals were destroyed at the time of surgery, two died during the immediate post-operative period and three were later destroyed because of suspected recurrence. Four dogs are reported well at intervals of between nine months and two years following surgery.     

Geographical, clinical, clinicopathological and radiographic features of canine angiostrongylosis in Irish dogs: a retrospective study

Background

Angiostrongylus vasorum infection is associated with high morbidity and mortality in dogs. Although recognised in Ireland, there are no large series of cases reported. The aim of this retrospective study was to identify pertinent clinical and geographical features in Irish dogs.

Results

The case records of dogs presenting to the University College Dublin Veterinary Hospital (1999-2010) were reviewed. A contemporaneous review of external faecal parasitology and post mortem submissions was also performed. A positive diagnosis of angiostrogylosis was identified in 49 dogs including 24 clinical, 10 post mortem and 15 external faecal sample cases. The majority (n = 44 (90%)) resided on the East Coast.In the clinical cases, the median age was 20 months, 29% of cases were older than 2 years. Clinical features included cardiorespiratory (63%), coagulopathic (71%) and other (63%) signs. Cough (n = 10), dyspnoea (n = 5) and tachypnoea (n = 3) were the most common cardiorespiratory abnormalities. Of animals with evidence of coagulopathy, excessive haemorrhage from a wound (n = 5), airway haemorrhage (n = 9), epistaxis (n = 3), haematoma (n = 4), suspected haemarthrosis (n = 3), neurological signs (n = 2) and haematuria (n = 1) were found. Ten dogs were anaemic, of which two were severe (haematocrit ≤ 0.20 L/L). Ten animals had thrombocytopenia, with four severely affected (≤50 × 10⁹/L). PT and APTT values were prolonged in 4 (24%) of 17 and a BMBT was prolonged in 5 (63%) of 8 cases. Vague signs of exercise intolerance (n = 6), lethargy (n = 6) and weakness (n = 2) were identified, with two (8%) animals having only these signs. In one animal the diagnosis appeared to be incidental. Thoracic radiographs (n = 19) identified abnormalities in 100% of cases. Four (17%) animals died before or within 24 hours of treatment and post mortem examinations confirmed angiostrongylosis. Fenbendazole was administered in 19 cases, 18 (95%) recovered. Two animals were euthanised, one which failed to respond to therapy and another in which an ante mortem diagnosis had not been made.

Conclusions

Angiostrongylosis is not uncommon in Ireland, is not confined to young dogs or the East Coast and can present with a wide variety of signs, particularly coagulopathic, respiratory or neurological signs.