Sporotrichosis: a retrospective evaluation of 23 cases seen in northern California (1987–2007)

Sporotrichosis is an uncommon to rare cutaneous and subcutaneous mycosis of animals and humans caused by the dimorphic fungus Sporothrix schenckii . Twenty-three mammalian cases of sporotrichosis examined between 1987 and 2007 at the University of California, Davis – Veterinary Medical Teaching Hospital, were retrospectively evaluated with regard to the historical, clinical, diagnostic and treatment findings. Cats were the most common species affected ( n  = 14). In addition, sporotrichosis was diagnosed in four dogs, four horses and a donkey. Six of 23 cases were diagnosed with the localized cutaneous form of sporotrichosis (four cats, one dog, one horse), 10 with the cutaneous-lymphatic form (four cats, two dogs, three horses and a donkey), and seven with the disseminated form (six cats, one dog). Two of 23 cases did not have skin lesions at the time of diagnosis (one cat, one dog). The most common mode of diagnosis was demonstration of S. schenckii on histopathological evaluation of tissue. In contrast with most previously described sporotrichosis infections in cats, few to no fungal organisms were seen in histopathological samples (haematoxylin and eosin and special stains) in five of the 14 cats. Treatments received included itraconazole (12 cats, one dog), ketoconazole (three dogs), fluconazole (one cat, one donkey), sodium iodide (four horses, one cat) and potassium iodide (one cat, one horse, one donkey). The prognosis for successful treatment was good in all species. Fluconazole was successful in inducing resolution of the cutaneous lesions and controlling the infection in one cat with disseminated sporotrichosis.     

MRI features of CNS lymphoma in dogs and cats

The magnetic resonance (MR) imaging features of central nervous system lymphoma in eight dogs and four cats are described. Intracranial lesions affected the rostrotentorial structures in six dogs and caudotentorial structures in two cats. Lesions affected the spinal cord in two dogs and in two cats. One dog and one cat with intracranial lymphoma had signs of local extracranial extension and lymphadenopathy. Lesions were considered extraparenchymal in four dogs and three cats, intraparenchymal in two dogs and one cat, and appeared to have both intra- and extraparenchymal components in two dogs. All lesions were hyperintense in T2-weighted images when compared to white matter, most were hypointense in T1-weighted images (7/12), and most were hyperintense in fluid-attenuated inversion recovery (FLAIR) images (5/9). When compared to grey matter, these lesions appear either isointense (5/12) or hyperintense (7/12) on T2-weighted images, half of them were hypointense in T1-weighted images (6/12), and most were isointense in FLAIR images (7/9). Lesion margins were usually indistinct in T2-weighted images (10/12) and had perilesional hyperintensity in FLAIR images (7/9). The majority of lesions (10/12) had abnormal meninges around the lesion and half (6/12) had generalized contrast enhancement. Mass effect was evident in all lesions. Although not specific, when combined with the history and neurologic signs, MR features aid presumptive diagnosis that should be confirmed by cytology or histopathology.     

Clinical Tolerance and Bronchoscopic Changes Associated With Transtracheal High-Frequency jet Ventilation in Dogs and Cats

Eleven awake dogs and two cats received high-frequency jet ventilation (HFJV) via a transtracheal catheter for 6 hours to evaluate their clinical tolerance to the technique. A bronchoscopic examination was performed in all animals prior to and the morning of the day after the procedure to determine the gross effects of the technique on the tracheal epithelium.
All animals tolerated the technique well, exhibiting no discomfort and only a minimal amount of coughing. Only one dog exhibited coughing on the day following the procedure. No bronchoscopic changes were noted after HFJV in one dog. In one dog and one cat, the only observed change was an increase in the prominence of the vascularity compared to that observed prior to HFJV. The remaining animals exhibited more severe tracheal changes that included: an accumulation of mucus (seven dogs, one cat), focal spots of hemorrhage (two dogs), linear stretches of epithelial denuding (two dogs), and diffuse reddening and epithelial denuding (four dogs).
High-frequency jet ventilation by a transtracheal intravenous catheter is well tolerated for short-term ventilatory support in dogs and cats, but the magnitude of the tracheal damage observed in the present report may preclude long-term ventilatory support by this tecnique.     

Mediastinal lymphoma in dogs is homogeneous compared to thymic epithelial neoplasia and is more likely to envelop the cranial vena cava in CT images

In order to identify CT signs that could be used to distinguish cranial mediastinal lymphoma and thymic epithelial neoplasia, a retrospective case‐control study was done. Associations between CT signs and diagnosis were tested using binary logistic regression and results expressed as odds ratio and 95% confidence interval. Sixty‐two dogs that had thoracic CT and confirmed diagnosis of lymphoma (n = 33) or thymic neoplasia (n = 29) were sampled. Thymic neoplasms included 24 thymomas and five thymic carcinomas. Dogs with thymic epithelial neoplasia were significantly older than dogs with lymphoma (median age 8.6 years versus 6.0 years, P = .007), but there were no significant differences in prevalence of clinical signs. Diagnosis of thymic epithelial neoplasia was associated with heterogeneous attenuation in pre‐ (odds ratio 23.3, 95% confidence interval, 4.5‐121.1) and post‐contrast (odds ratio 30.7, 95% confidence interval, 3.6‐265.0) images. Conversely, envelopment of the cranial vena cava by the mass was less likely with thymic epithelial neoplasia than lymphoma (odds ratio 0.07, 95% confidence interval, 0.007‐0.66). Greater standard deviation of Hounsfield unit values in post‐contrast images was associated with thymic epithelial neoplasia (P = .005). Based on ROC analysis, SD > 17HU of the mass in post‐contrast images had a sensitivity of 72% and specificity of 79% for thymic epithelial neoplasia. There were no significant differences in morphology, prevalence of calcification, mediastinal lymphadenopathy, cranial vena cava invasion, collateral vessels, or pleural fluid associated with these tumors. Thymic epithelial neoplasms tended to occur in older dogs and were heterogeneous in CT images, whereas mediastinal lymphoma was more homogeneous and more likely to envelop the cranial vena cava.     

Evaluation of risk factors for bite wounds inflicted on caregivers by dogs and cats in a veterinary teaching hospital

OBJECTIVE: To identify factors associated with increased risk of being bitten by a dog or cat in a veterinary teaching hospital. DESIGN: Unmatched case-control study. STUDY POPULATION: 207 animal caregivers. PROCEDURE: Case subjects (n = 75) were any caregiver that reported being bitten by a dog or cat. Control subjects (n = 132) were randomly selected from a list of all caregivers interacting with dogs or cats. Information on the characteristics of the caregivers, characteristics of the dogs and cats, and the nature of the interaction between the dog or cat and the caregiver was obtained by use of self-administered questionnaires. RESULTS: Caregivers were more likely to be bitten by dogs or cats that had warning signs on their cages indicating the potential to bite or that were considered difficult to handle. Caregivers interacting with cats or with older dogs and cats were more likely to be bitten. Only 37 to 55% of dogs and cats that had characteristics traditionally associated with biting or were considered likely to bite were muzzled. CONCLUSIONS AND CLINICAL RELEVANCE: Muzzling dogs and cats should be considered more frequently. Dogs and cats considered to have the propensity to bite frequently do bite, and precautions, such as muzzling, should be taken if the medical condition or conformation of the dog or cat is amenable to this type of restraint.     

Post‐anesthesia deafness in dogs and cats following dental and ear cleaning procedures

Objective The present study was performed to document hearing loss in dogs and cats following procedures performed under anesthesia. Most cases of reported hearing loss were subsequent to dental and ear cleaning procedures. Study design Prospective and retrospective case survey. Animals Subjects were dogs and cats with deafness, personally communicated to one author, cases discussed on a veterinary information web site, and cases communicated through a survey of general practice and dental specialist veterinarians. Methods Reported deafness cases were characterized by species (dog, cat), breed, gender, age, and dog breed size. Results Sixty‐two cases of hearing loss following anesthesia were reported between the years 2002 and 2009. Five additional cases were reported by survey respondents. Forty‐three cases occurred following dental procedures. Sixteen cases occurred following ear cleaning. No relationship was observed between deafness and dog or cat breed, gender, anesthetic drug used, or dog size. Geriatric animals appeared more susceptible to post‐anesthetic, post‐procedural hearing loss. Conclusions Deafness may occur in dogs and cats following anesthesia for dental and ear cleaning procedures, but the prevalence is low. The hearing loss appears to be permanent. Clinical relevance Deafness can be a consequence following anesthesia for dental or ear cleaning procedures. Older animals may have greater susceptibility.     

Treatment of fractures of the mandible and maxilla by mini titanium plate fixation systems in dogs and cats

Mini titanium plates were used to repair certain fractures of the maxilla and mandible in dogs and cats, under general anaesthesia. The location of the fractures treated were: corpus mandible, one dog; corpus mandible and symphysis, two dogs; caudal mandible, two dogs; rostral mandible, one dog; maxilla, one dog; nasal bone, one dog; corpus mandible and symphysis, one cat; caudal mandible, one cat; and maxilla, one cat. The healing periods varied from 6 to 9 weeks. In seven cases, implants were removed after a period of 3.5 to 18 months. In four cases the implants were left in place. The follow up period was between 8 and 36 months. In ten cases the procedure was successful, however in one case the outcome was not satisfactory due to a broken plate. There were no instances of dental malocclusion, nonunion, malunion, osteomyelitis or soft tissue infection. Eating, playing with toys, a fast transition to solid food and a quick return to normal jaw movements were observed. In our hands, the mini titanium plate fixation system was a safe and effective method for repairing certain maxillary and mandibular fractures in dogs and cats.     

Stomach wall evaluation using helical hydro-computed tomography

In helical hydro-computed tomography (helical hydro-CT), water is used as a neutral luminal contrast medium together with intravenous iodine contrast medium for the diagnosis and staging of human gastric neoplasia. We evaluated the feasibility of helical hydro-CT in 11 healthy animals (nine dogs and two cats). Adequate uniform gastric distension was obtained with 30 ml water/kg body weight. Fourteen client-owned dogs and four cats with suspected or diagnosed gastric neoplasia then underwent helical hydro-CT followed by intravenous contrast medium administration. Focal thickening with moderate contrast enhancement was found in 10 dogs and 3 cats. The extent of the lesion was assessed easily in all these patients. Three dogs and one cat had a normal stomach wall. One dog had multifocal thickening of the antrum but no histopathologic diagnosis was made. Helical hydro-CT, followed by intravenous contrast medium administration, is a simple technique for assessing the stomach wall.     

Lymphoma (malignant lymphoma, lymphosarcoma) in the dog

This report describes seven cases of canine lymphoma involving three German shepherd dogs, two boxers and two mongrels with a male to female ratio of 1–3 to 1. Their mean age and body weight was four years (range 1–5 to 8) and 31 kg (range 21 to 40), respectively. Six of the animals were euthanased at their owner's request and one died. Excessive lymph node enlargement, splenomegaly, hepatomegaly, blood lymphocytosis and proteinuria were the most striking clinical and clinicopathological findings. All the cases except one presented systemic signs and three developed secondary leukaemia because of bone marrow involvement. The anatomical types were classified according to the World Health Organization's criteria as thymic (one dog) and generalised (six dogs) and the clinical stage as IV (four dogs) and V (three dogs). Extranodal lymphomas involving the kidneys, meninges and the alimentary tract were seen in two cases. Histologically, the lymphomas were classified as lymphoblastic in four dogs, and in the remaining animals as lymphoblastic with plasmacytoid differentiation, lymphocytic with plasmacytoid differentiation, and poorly differentiated (stem cell) with one type appearing in each dog.     

Dysplasia of the tricuspid valve in the dog and cat.

Dysplasia of the tricuspid valve in 14 dogs and 13 cats was studied. The clinical, electrocardiographic, radiographic, hemodynamic, angiocardiographic, and pathologic findings were reviewed in each species. Alterations of the tricuspid valve complex included long, thick septal leaflets adhered to the septum; absent or short, stout fused chordae tendineae; hypertrophic fused papillary muscles; insertion of papillary muscles directly into the lateral leaflets; incomplete development of the valvular tissue; and enlargement of the right atrium and ventricle. Additional intracardiac anomalies included malformation of the mitral valve complex (5 dogs and 3 cats), ventricular septal defect (3 dogs and 3 cats), pulmonary stenosis (1 dog and 1 cat), aortic stenosis (1 dog and 1 cat), and persistent left cranial vena cava (1 dog).     

RADIOGRAPHIC APPEARANCE OF CONFIRMED PULMONARY LYMPHOMA IN CATS AND DOGS

Herein we describe the thoracic radiographic appearance of confirmed pulmonary lymphoma. Patients with thoracic radiographs and cytologically or histologically confirmed pulmonary lymphoma were sought by contacting American College of Veterinary Radiology members. Seven cats and 16 dogs met the inclusion criteria, ranging in age from 4 to 15 years. Method of diagnosis was via ultrasound‐guided cytology (four), surgical biopsy (two), ultrasound‐guided biopsy (one), and necropsy (16). Radiographic findings varied but ranged from normal (one) to alveolar (six) and/or unstructured interstitial infiltrates (11), nodules and/or masses (eight), and bronchial infiltrates (four). Additional thoracic radiographic findings included pleural effusion and lymphadenopathy. The results of this evaluation indicate a wide variability in thoracic radiographic abnormalities in cats and dogs with pulmonary lymphoma.     

New perspectives about Hemotrophic mycoplasma (formerly, Haemobartonella and Eperythrozoon species) infections in dogs and cats.

The new perspectives about hemotrophic mycoplasma infections in cats and dogs can be summarized as follows: Haemobartonella and Eperythrozoon species infecting the dog and cat have been reclassified as mycoplasmal parasites and given the names M haemofelis (Ohio or large form of H felis), M haemominutum (California or small form of H felis), and M haemocanis (H canis). The prevalence of hemotrophic mycoplasma infections in anemic cats in the United States is about 25% and usually involves M haemofelis. However, nonanemic cats may also be infected most commonly with M haemominutum. Chronic infections with hemotrophic mycoplasmas may promote myeloproliferative disorders in FeLV-infected cats. M haemocanis infection in dogs may be a widespread latent disease in kennel-raised dogs and is being investigated. The PCR assay is exquisitely sensitive for detection of M haemofelis and M haemominutum, and testing of blood donor cats and perhaps dogs should be done regularly. Fleas are involved in the transmission of M haemofelis to the cat, whereas R sanguines may be involved with transmission of M haemocanis to the dog. Treatment with doxycycline effectively controls acute infection in the cat and dog, and enrofloxacin may also be effective in the cat, but none of the antibiotics tested to date consistently clears the parasites.     

Iatrogenic sciatic nerve injury in eighteen dogs and nine cats (1997-2006)

Objective— To report clinical features associated with iatrogenic peripheral nerve injury in dogs and cats admitted (1997–2006) to a referral teaching hospital.
Study Design— Retrospective study.
Animals— Dogs (n=18), 9 cats.
Methods— Patients had acute signs of monoparesis attributable to sciatic nerve dysfunction that developed after treatment. Neurologic examination and electrodiagnostic testing were performed. Surgical therapy was used for nerve entrapment and delayed reconstructive surgery used in other cases.
Results— Of 27 nerve injuries, 25 resulted from surgery (18 with treatment of pelvic injuries). Iliosacral luxation repair resulted in tibial (4 cats) and peroneal (3 dogs) nerve dysfunction. Other causes were intramedullary pinning of femoral fractures (3), other orthopedic surgery (cemented hip prosthesis [2] and tibial plateau-leveling osteotomy [1]), and perineal herniorrhaphy [1]. Nerve injury occurred after intramuscular injection (1 cat, 1 dog). Immediate surgical treatment was removal of intramedullary nails, extruded cement, or entrapping suture. Delayed nerve transplantation was performed in 2 dogs. Within 1 year, 13 patients recovered completely, clinical improvement occurred in 7, and there was no improvement in 7. Five of the 7 dogs that did not recover had acetabular or ilium fracture.
Conclusion— Iatrogenic sciatic nerve injury occurred most commonly during treatment of pelvic orthopedic diseases and had a poor prognosis. Clinical variation in sciatic nerve dysfunction in dogs and cats can be explained by species anatomic differences.
Clinical Relevance— Iatrogenic sciatic nerve injury leads to severely debilitating locomotor dysfunction with an uncertain prognosis for full-functional recovery.     

Comparative metabolism of mycophenolic acid by glucuronic acid and glucose conjugation in human,dog, and cat liver microsomes

Use of the immunosuppressant mycophenolic acid (MPA) in cats is limited because MPA elimination depends on glucuronidation, which is deficient in cats. We evaluated formation of major (phenol glucuronide) and minor (acyl glucuronide, phenol glucoside, and acyl glucoside) MPA metabolites using liver microsomes from 16 cats, 26 dogs, and 48 humans. All MPA metabolites were formed by human liver microsomes, while dog and cat liver microsomes formed both MPA glucuronides, but only one MPA glucoside (phenol glucoside). Intrinsic clearance (CLint) of MPA for phenol glucuronidation by cat liver microsomes was only 15–17% that of dog and human liver microsomes. However, CLint for acyl glucuronide and phenol glucoside formation in cat liver microsomes was similar to or greater than that for dog and human liver microsomes. While total MPA conjugation CLint was generally similar for cat liver microsomes compared with dog and human liver microsomes, relative contributions of each pathway varied between species with phenol glucuronidation predominating in dog and human liver microsomes and phenol glucosidation predominating in cat liver microsomes. MPA conjugation variation between cat liver microsomes was threefold for total conjugation and for phenol glucosidation, sixfold for phenol glucuronidation, and 11‐fold for acyl glucuronidation. Our results indicate that total MPA conjugation is quantitatively similar between liver microsomes from cats, dogs, and humans despite large differences in the conjugation pathways that are utilized by these species.     

Comparative evaluation of net digestive and absorptive efficiency in dogs and cats fed a variety of contrasting diet types

Comparative net digestive and absorptive efficiency was assessed with adult Beagles and domestic cats by apparent digestibility assays. Eight foods were used comprising two canned dog foods; canned cat foods; two samples of semipurified diet; and single samples of experimental dry cat food and fresh mince. Apparent digestibility percentages of crude protein, fat, nitrogen-free extract (NFE) and gross energy were all significantly higher in dogs than cats. Mean values obtained for dogs were (per cent): crude protein 87; fat 92; NFE 70 and energy 89. Respective values for cats were 82, 76, 67 and 79. On average, dogs obtained 11 and 9 per cent more digestible energy and protein per unit food eaten than cats. Most digestibility characteristics of foods measured in cats were significantly correlated with those for dogs and regression equations are presented predicting digestibility in cats from dog data.     

Feline cholecystitis and acute neutrophilic cholangitis: clinical findings, bacterial isolates and response to treatment in six cases

Clinicopathological findings from six cats with confirmed cholecystitis or acute neutrophilic cholangitis are presented. Historical findings included lethargy and anorexia or inappetence of up to five days duration. On physical examination all cats were pyrexic and four out of six were jaundiced and had cranial abdominal pain. Bile samples were obtained by cholecystocentesis at exploratory coeliotomy (two cases) or by percutaneous, ultrasound-guided cholecystocentesis (four cases). Gall bladder rupture and bile peritonitis occurred subsequent to ultrasound-guided cholecystocentesis in one case. The most common bacterial isolate was Escherichia coli (four cases); E coli was isolated alone in two cases, in combination with a Streptococcus species (one case) and in combination with a Clostridium species (one case). Streptococcus species alone was isolated from one case, as was Salmonella enterica serovar Typhimurium. The latter is the first reported case of Salmonella-associated cholecystitis in a cat. Concurrent pancreatic or intestinal disease was detected histologically in three cases. All cases were treated with antimicrobials based on in vitro susceptibility results. Treatment was successful in five cases. One cat with concurrent diffuse epitheliotropic intestinal lymphoma was euthanased. Percutaneous ultrasound-guided cholecystocentesis is an effective, minimally-invasive technique enabling identification of bacterial isolates in cats with inflammatory hepatobiliary disease.     

Effect of breed on anatomy of portosystemic shunts resulting from congenital diseases in dogs and cats: a review of 242 cases

OBJECTIVE: To evaluate the effect of species and breed on the anatomy of portosystemic vascular anomalies in dogs and cats. DESIGN: Retrospective study of 233 dogs and nine cats presenting to the University Veterinary Centre, Sydney. METHODS: Case records were evaluated for breed, sex, age, anatomical and histological diagnosis. Cases were included when a portosystemic vascular anomaly resulted from a congenital or developmental abnormality of the liver or portal venous system. RESULTS: Disease conditions included single congenital portosystemic shunt with patent portal vasculature (214 dogs, nine cats), portal vein aplasia (nine dogs), multiple acquired shunts resulting from portal vein hypoplasia (seven dogs), biliary atresia (one dog) and microvascular dysplasia (one dog). One Maltese had a single, congenital shunt and multiple acquired shunts resulting from hepatic cirrhosis. Breeds that were significantly over-represented included the Maltese, Silky Terrier, Australian Cattle Dog, Bichon Frise, Shih Tzu, Miniature Schnauzer, Border Collie, Jack Russell Terrier, Irish Wolfhound and Himalayan cat. Bichon Frise with shunts were significantly more likely to be female than male (12:2, P < 0.001). Two hundred and fourteen dogs (91.4%), and all cats, had shunts that were amenable to attenuation. Inoperable shunts occurred in 19 dogs (8.2%). Fifty six of 61 (92%) operable shunts in large breed dogs were intrahepatic, versus 10/153 (7%) in small breeds (P < 0.0001). Breeds that were not predisposed to portosystemic shunts were significantly more likely to have unusual or inoperable shunts than dogs from predisposed breeds (29% versus 7.6%, P < 0.0001). No significant relationship between breed and shunt type could be determined in cats. CONCLUSION: Breed has a significant influence on shunt anatomy in dogs. Animals presenting with signs of portosystemic shunting may suffer from a wide range of operable or inoperable conditions. Veterinarians should be aware that unusual or inoperable shunts are much more likely to occur in breeds that are not predisposed to congenital portosystemic shunts.     

The role of para-aminophenol in acetaminophen-induced methemoglobinemia in dogs and cats

Acetaminophen (APAP) overdose in most species is associated with hepatotoxicity because of the metabolite N -acetyl- p -benzoquinoneimine (NAPQI). In dogs and cats, APAP overdose primarily causes methemoglobinemia and hemolysis. Although NAPQI has been proposed as the responsible intermediate in dogs and cats, it lacks chemical or pharmacokinetic characteristics that favor methemoglobin formation. We hypothesized that para -aminophenol (PAP) rather than NAPQI induces methemoglobinemia and that deficient arylamine N -acetyltransferase (NAT) activity in dogs and cats contributes to this species-dependent methemoglobinemia. Erythrocytes from dogs, cats, mice, and rats were exposed in vitro to APAP, NAPQI, and PAP. Only PAP induced methemoglobin and it induced more methemoglobin formation in dog and cat than rat and mouse erythrocytes. PAP also induced more methemoglobin in erythrocytes from Nat1/Nat2 knockout mice than wildtype (WT) mouse erythrocytes ( P  <   0.05), but less than in dog and cat erythrocytes ( P  <   0.01). APAP and PAP toxicity were compared in vivo in WT and Nat1/Nat2 knockout mice. APAP caused no hematotoxicity while PAP induced more methemoglobin in NAT1/NAT2 knockout mice than in WT mice ( P  <   0.05). These results support the hypothesis that PAP is the metabolite responsible for APAP-induced methemoglobinemia and that deficient NAT activity in dogs and cats contributes to this species-dependent toxicity.     

Attitudes of the public towards dogs and cats as companion animals

A questionnaire was used to collect information on attitudes toward dogs and cats as companion animals. Thirty-nine attitudinal questions on dogs were grouped using principal component analysis (PCA) into six independent major factors; whereas, 38 items on cats were grouped using principal component analysis (PCA) into four independent major factors. In addition, 18 items which did not fit the PCA model but that were related to the respondents' attitudes towards dogs and cats as companion animals were analysed separately. The hypotheses tested, using analysis of variance (ANOVA) were that there was no significant relationship between the factors and five variables, i.e., pet ownership, age or sex of the respondents and their like or dislike of either dogs or cats. The respondents' like or dislike of dogs or cats influenced their attitudes towards ownership of companion animals. Furthermore, nonowners stated they derive minimal value from a dog or cat as a pet and viewed the negative characteristics of the animal itself per se as a more important factor in determining ownership. Female respondents were more emotionally involved and younger owners derived more of a feeling of importance-vanity from dog or cat ownership.