ABSTRACT
Systemic protothecosis was diagnosed in 17 Australian dogs between 1988 and 2005. There was a preponderance of young-adult (median 4 years), medium- to large-breed dogs. Females (12/17 cases) and Boxer dogs (7 cases, including 6 purebreds and one Boxer cross) were over-represented. Sixteen of 17 dogs died, with a median survival of four months. A disproportionate number of cases were from coastal Queensland. In most patients, first signs were referable to colitis (11/17 cases), which varied in severity, and was often present for many months before other symptoms developed. Subsequent to dissemination, signs were mostly ocular (12 cases) and/or neurologic (8 cases). Two dogs had signs due to bony lesions. Once dissemination was evident, death or euthanasia transpired quickly. Prototheca organisms had a tropism for the eye, central nervous system (CNS), bone, kidneys and myocardium, tissues with a good blood supply. Microscopic examination and culture of urine (5 cases), cerebrospinal fluid (CSF;1 case), rectal scrapings (4 cases), aspirates or biopsies of eyes (5 cases) and histology of colonic biopsies (6 cases) as well as skin and lymph nodes (2 cases) helped secure a diagnosis. Of the cases where culture was successful, P wickerhamii was isolated from two patients, while P zopfii was isolated from five. P zopfii infections had a more aggressive course. Treatment was not attempted in most cases. Combination therapy with amphotericin B and itraconazole proved effective in two cases, although in one of these treatment should have been for a longer duration. One surviving dog is currently still receiving itraconazole. Protothecosis should be considered in all dogs with refractory colitis, especially in female Boxers.
Subject(s)
Dog Diseases/microbiology , Infections/veterinary , Prototheca/isolation & purification , Age Factors , Animals , Australia , Biopsy , Bone and Bones/diagnostic imaging , Bone and Bones/pathology , Central Nervous System/pathology , Cohort Studies , Colitis/microbiology , Colitis/pathology , Colitis/veterinary , Colon/microbiology , Colon/pathology , Dog Diseases/mortality , Dog Diseases/pathology , Dog Diseases/physiopathology , Dogs , Eye/pathology , Female , Histocytochemistry , Infections/complications , Infections/microbiology , Infections/mortality , Infections/pathology , Kidney/pathology , Male , Myocardium/pathology , Radiography , Rectum/microbiology , Retrospective Studies , Sex FactorsABSTRACT
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.
Subject(s)
Dog Diseases/etiology , Myasthenia Gravis/veterinary , Thymoma/veterinary , Thymus Neoplasms/veterinary , Acetylcholine/immunology , Animals , Antibodies/blood , Dog Diseases/drug therapy , Dog Diseases/surgery , Dogs , Esophageal Achalasia/etiology , Esophageal Achalasia/veterinary , Male , Myasthenia Gravis/etiology , Neoplasm Recurrence, Local , Receptors, Cholinergic/immunology , Thymoma/complications , Thymoma/drug therapy , Thymoma/surgery , Thymus Neoplasms/complications , Thymus Neoplasms/drug therapy , Thymus Neoplasms/surgeryABSTRACT
An 8-year-old Golden Retriever dog was presented with a 10-month history of right-sided exophthalmos. Radiographs and CT demonstrated a linear density, suggestive of a foreign body, in the region of the ramus of the right mandible. A 7 cm stick, located medial to the right zygomatic arch, was removed during exploratory surgery. The dog recovered with the aid of antibiotics, however was left with a residual facial nerve paralysis.
