Prevalence of vector-borne pathogens in dogs from Haiti.

Canine vector-borne pathogens are common on some Caribbean islands, but survey data in Haiti are lacking. To determine the prevalence of selected vector-borne pathogens in dogs from Haiti, we tested blood samples collected from 210 owned dogs, 28 (13.3%) of which were infested with Rhipicephalus sanguineus ticks at the time of blood collection. No other tick species were identified on these dogs. A commercially available ELISA identified antibodies to Ehrlichia spp. in 69 (32.9%), antibodies to Anaplasma spp. in 37 (17.6%), and antigen of Dirofilaria immitis in 55 (26.2%); antibodies to Borrelia burgdorferi were not detected in any sample. Molecular assays of whole blood from 207 of the dogs confirmed infection with Ehrlichia canis (15; 7.2%), Anaplasma platys (13; 6.3%), D. immitis (46; 22.2%), Wolbachia spp. (45; 21.7%), Babesia vogeli (16; 7.7%), and Hepatozoon canis (40; 19.3%), but Anaplasma phagocytophilum, Babesia canis, Babesia rossi, Babesia gibsoni, Ehrlichia chaffeensis, Ehrlichia ewingii, or Hepatozoon americanum were not detected. Co-infection with two or more vector-borne pathogens was detected by serology in 42 (20.0%) dogs and by molecular assays in 22 (10.6%) dogs; one dog was co-infected with B. vogeli and E. canis as detected by PCR with D. immitis detected by serology (antigen). Overall, evidence of past or current infection with at least one vector-borne pathogen was identified in 142/210 (67.6%) dogs in this study, underscoring the common nature of these pathogens, some of which are zoonotic, in Haiti.

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.

North American snake envenomation in the dog and cat.

Snake envenomation can be a cause of significant morbidity in dogs and cats in North America. Being familiar with the venomous snakes in your area and understanding the mechanisms of action of their venom will allow for successful treatment of envenomation cases. Treatment of snake envenomation revolves around supportive care in mild to moderate cases and venom neutralization with antivenom in severe cases. Dogs and cats envenomated by North American snakes have a good prognosis if treated appropriately.

Sellar xanthogranuloma in a dog.

A 7-year-old, intact male standard Poodle dog with hypothyroidism and atypical hyperadrenocorticism developed acute signs of lethargy, weakness, inappetence, vomiting, and diarrhea. Clinical signs progressed to hind limb proprioceptive deficits, aggressive behavior with obtundation, and an equivocal seizure. Necropsy revealed a mass in the sellar region that histologically consisted of multinucleated giant cells, macrophages, and hemosiderin-laden macrophages with fewer lymphocytes and plasma cells admixed with large regions of cholesterol cleft deposition, fibrin, and prominent Rosenthal fibers. Pituitary tissue was not identified on gross or histologic examination, but the mass was partially bordered by epithelial cells. The histologic characteristics are similar to changes described in the human medical literature as xanthogranuloma of the sellar region and xanthogranulomatous hypophysitis.

Pulmonary Paecilomyces lilacinus Infection in a Cat.

A 6-year-old, spayed female domestic shorthair cat was referred for an intermittent cough and wheezing of 3 to 4 months' duration. Thoracic radiography revealed atelectasis of the right middle and caudal lung lobes with hyperinflation of the accessory lobe, consistent with bronchial obstruction. Bronchoscopy confirmed a narrowing of the right mainstem bronchial lumen; however, positive-pressure ventilation resulted in a severe pneumothorax. A lateral thoracotomy and right caudal lung lobectomy resulted in complete resolution of the pneumothorax and respiratory signs. Histopathology and culture of the lung revealed Paecilomyces lilacinus. The cat was placed on itraconazole therapy for 6 months. Since dismissal from the hospital, the cat has not exhibited clinical evidence of wheezing, coughing, or dyspnea and is neurologically normal.

Indices of urine N-acetyl-beta-D-glucosaminidase and gamma-glutamyl transpeptidase activities in clinically normal adult dogs.

OBJECTIVE: To establish reference ranges for indices of urine N-acetyl-B-D-glucosaminidase (NAG) and gamma-glutamyl transpeptidase (GGT) activities in clinically normal adult dogs. ANIMALS: 38 dogs. PROCEDURES: Each dog underwent a physical examination, CBC, serum biochemical analysis, urinalysis, and serologic testing for heartworm antigen and antibodies against Ehrlichia canis and Borrelia burgdorferi. Activities of NAG and GGT in urine were evaluated, and values of the respective indices were determined as urine NAG or GGT activity (U/L) divided by urine creatinine concentration (g/L). RESULTS: All dogs were considered clinically normal. A 90% prediction interval based on the 5th and 95th percentiles for GGT and NAG index values from both sexes was used to establish the reference ranges for dogs: 1.93 to 28.57 U/g and 0.02 to 3.63 U/g, respectively. Between males and females, urine NAG index differed significantly, whereas urine GGT index did not. When accounting for sex differences, reference ranges for the urine NAG index in males and females were 0.02 to 3.65 U/g and 0.02 to 2.31 U/g, respectively. Changes in urine pH significantly affected the urine GGT index but not the urine NAG index. Neither index changed significantly with changes in body surface area. CONCLUSIONS AND CLINICAL RELEVANCE: Data suggest that increases in urine NAG and GGT indices allow for earlier detection of renal tubular damage in dogs. Such early detection would enable adjustment of the clinical management of affected dogs to decrease morbidity and death rates associated with acute tubular injury and acute tubular necrosis.

Dendritic cell leukemia in a Golden Retriever.

An 8-year-old castrated male Golden Retriever was evaluated for decreased appetite, lethargy, and labored breathing of 1-week duration. Bilateral pulmonary infiltrates, hepatomegaly, and splenomegaly were present. Results of a CBC revealed marked leukocytosis (62,600/microL; reference interval 4000-15,500/microL) and large numbers of atypical cells (30,700/microL) with abundant cytoplasm. There was no concurrent anemia, neutropenia, or thrombocytopenia. Morphology of the atypical cells was most consistent with a histiocytic origin. Similar cells were identified in bone marrow aspirates, and were morphologically suggestive of the macrophage variant of disseminated histiocytic sarcoma. However, flow cytometry of the abnormal circulating cells revealed CD1c, CD11c, and major histocompatibility complex (MHC) Class II expression without expression of CD11d or lymphoid markers, consistent with myeloid dendritic antigen-presenting cells. At necropsy, the splenic architecture was effaced by neoplastic histiocytes that were also infiltrating lung, liver, an abdominal lymph node, myocardium, an bone marrow. Immunohistochemistry of the splenic neoplastic cells confirmed dendritic cell origin (CD1c+, CD11c+, MHC II+, no expression of CD11d and lymphoid markers). To the authors' knowledge, this is the first report of canine dendritic cell leukemia-in this instance accompanied by marked tissue infiltration.

B-cell lymphoma in a dog with ehrlichiosis (Ehrlichia canis) and systemic histoplasmosis (Histoplasma capsulatum).

A mixed breed dog treated for ehrlichiosis and systemic histoplasmosis developed a refractory thrombocytopenia. When an abdominal mass was detected, exploratory laparotomy and biopsies confirmed lymphoma, which on immunohistochemical stains was determined to be of B-cell origin. Conceivably, the B-cell lymphoma in this dog was associated with chronic inflammation from ehrlichiosis, histoplasmosis, or both.

Cytologic identification of immature endospores in a dog with rhinosporidiosis.

An 8-year-old, intact, male Labrador Retriever was presented to the Boren Veterinary Medical Teaching Hospital at Oklahoma State University with a 2-month history of severe sneezing episodes that resulted in epistaxis and bilateral sanguineous discharge. Rhinoscopy revealed a small polypoid mass, and specimens were obtained for histopathology. Microscopic examination of formalin-fixed tissue specimens revealed organisms consistent with Rhinosporidium seeberi. The mass was surgically excised and impression smears were made for cytology examination. Smears revealed high numbers of endospores, typical of those previously described for R seeberi. In addition, numerous smaller structures, presumed to be immature endospores, were noted. The immature endospores were morphologically distinct from mature endospores and have not been described previously. Recognition of immature forms of Rhinosporidium may help prevent misidentification of the organism or misdiagnosis of a dual infection.