Dysgonic strain of Microsporum canis pseudomycetoma in a Domestic Long-hair cat

A 4-year-old Domestic Long-hair cat was presented with two large non-painful, ulcerated and suppurative lesions over the flanks. Histopathology and cytology were consistent with fungal pyogranulomatous inflammation. Culture of tissue yielded a dysgonic strain of Microsporum canis. The cat was treated successfully by staged en bloc resections of the lesions, followed by oral ketoconazole, then oral terbinafine. This is the first reported case of dermatophytic pseudomycetoma in a Domestic Long-hair cat in Australia.     

Generalized Microsporum canis dermatophytosis in six Yorkshire terrier dogs

Six Yorkshire terrier dogs with generalized, chronic dermatophytosis caused by Microsporum canis were seen over a 3-year period. Specific tests showed that they also had concurrent leishmaniosis (four cases), leishmaniosis and ehrlichiosis (one case) or diabetes mellitus (one case). Although specific therapy for these infectious diseases was instituted and the dogs were treated systemically and topically with appropriate antifungal drugs, only partial clinical resolution of the dermatophytosis was achieved. M. canis infection resolved in the dog with diabetes mellitus after stabilizing the diabetes mellitus. Although immunological studies were not performed in these cases, it is theorized that the immune disregulation caused by leishmaniosis, ehrlichiosis or diabetes mellitus may have favoured generalization of the infection and prevented favourable responses to appropriate treatment of the M. canis infection.     

Development of an in vitro, isolated, infected spore testing model for disinfectant testing of Microsporum canis isolates

The isolated infected hair model is a commonly used technique to test the fungicidal efficacy of topical therapies against Microsporum canis. The most commonly used model uses mats of infective hairs, and results from various laboratories have differed. The objectives of this study were to develop a method to produce spores for testing when only mycelial forms were available and to develop a semiquantitative testing method that used only infective spores from hairs, and not pooled hair samples for testing. Ten isolates of M. canis were used in this study. Juvenile guinea pigs were easily infected using mycelial forms of M. canis and large numbers of spores were easily harvested for testing. Eight dilutions of disinfectants were tested. Fungal culture data were evaluated using an endpoint dilution at which there was 100% fungicidal activity, i.e. no growth on the plates. The 10 samples showed identical results. Chlorhexidine and Virkon(R) S were ineffective even when used at x4 the manufacturer's recommended dilution. Lime sulphur (1 : 33), enilconazole (20 microL mL(-1)), and bleach (1 : 10) were consistently effective when used at the recommended dilution. In addition, lime sulphur and enilconazole were 100% fungicidal even when the recommended concentration was diluted 1 : 4 or x4 as dilute as recommended.     

Efficacy of pre-treatment with lufenuron for the prevention of Microsporum canis infection in a feline direct topical challenge model

Oral lufenuron is reportedly an effective treatment for some cats with dermatophytosis. The purpose of this study was to determine if lufenuron, when used as a pre-treatment prior to challenge exposure, would be protective against the development of infection after the direct topical application of fungal macrocondia (Microsporum canis spores). Three groups (n = 6/group) of juvenile cats were treated with either monthly oral lufenuron (30 or 133 mg/kg) or placebo. After 2 months of treatment, kittens were challenged using 10(5)Microsporum canis spores applied to the skin under occlusion. Cats were examined weekly and the following data collected: Wood's lamp examination; scoring for scale/crust, erythema and induration; lesion size; and the development of satellite lesions. Fungal cultures were performed bi-weekly. All cats became infected; the infections progressed, and then regressed, in a similar fashion in all groups. There were no consistent statistically significant differences in weekly infection scores between treated and untreated cats throughout the study. Treated cats did not recover faster than untreated cats. We conclude that oral lufenuron at the dosing schedule and conditions used in this study did not prevent dermatophytosis or alter the course of infection by direct topical challenge.     

Uveitis associated with septic peritonitis in a cat

Objective – To report a case of bilateral uveitis believed to be a consequence of septic peritonitis in a 19‐month‐old cat. Case Summary – Bilateral anterior uveitis with suspicion of extension to the posterior segment was documented in a previously healthy young cat during hospitalization for severe septic peritonitis. Based on medical history and other findings uveitis was believed to result from concurrent abdominal sepsis, due either to metastatic seeding of bacterial organisms or to effects of bacterial toxins and inflammatory mediators on the blood‐aqueous barrier. The cat was surgically and medically managed, and made a full recovery with respect to both his ocular and his abdominal disease. New or Unique Information Provided – Ocular complications secondary to systemic sepsis are well documented in people but seldom reported in the veterinary literature. To the authors' knowledge this is the first report of uveitis linked to septic peritonitis in any veterinary species and the first to report sepsis‐related uveitis in a cat. Ocular inflammatory disease in the context of critical illness deserves attention as a potential significant source of morbidity. The development of ocular inflammatory disease may serve as a sentinel lesion for systemic sepsis and other life‐threatening conditions.     

Presumed post‐traumatic ocular chondrosarcoma with intrathoracic metastases in a cat

An indoor‐only, 5‐year‐old, spayed female domestic shorthair cat presented for an ophthalmic examination of the left eye. An intraocular tumor with secondary glaucoma and blindness was diagnosed; the globe was enucleated and sent for histopathological examination. Gross examination revealed a solid white mass filling the entire vitreous space and replacing the iris and ciliary body. The lens and retina appeared to be similarly replaced by the neoplasm. Histological examination revealed a complete loss of the internal ocular structures, with a ruptured capsule as the only remnant of the lens within an extensive malignant mesenchymal neoplastic cell proliferation. The cells were polygonal, with well‐defined cytoplasmic borders and abundant weakly basophilic cytoplasm, embedded within the islands of chondroid matrix. No neoplastic invasion of the sclera was apparent. The animal died 6 months after the enucleation due to respiratory distress. Gross examination revealed numerous firm, white to tan nodular masses with smooth to mildly irregular surfaces dispersed throughout the parietal pleura, thoracic surface of the diaphragm, tracheobronchial and mediastinal lymph nodes, pericardium, and lungs. On cross‐section, the neoplastic nodules were solid and variably translucent, resembling hyaline cartilage. Histologically, these nodules were similar to the neoplasm identified earlier in the left globe. Metastasis of post‐traumatic ocular chondrosarcoma has not yet been described in cats. This is therefore believed to be the first report of metastases of this type of neoplasm in cats. This case adds to the limited set of data on the outcome of this type of tumor.     

Treatment of dermatophytosis in dogs and cats: review of published studies

The recent literature on the treatment of dermatophytosis in dogs and cats was reviewed. Based upon in vitro studies using isolated infected hairs and controlled or field in vivo studies, the following topical treatments were consistently found to be antifungal (i.e. antidermatophyte): lime sulfur (1:16), 0.2% enilconazole rinses, and a combined 2% miconazole/chlorhexidine shampoo. Animals or hairs were either bathed or rinsed once or twice weekly. Itraconazole, griseofulvin and terbinafine were evaluated in controlled or field studies, most commonly involving cats. Griseofulvin (50 mg kg(-1)) was reported to cure infected animals in 41-70 days. Itraconazole (10 mg kg(-1) once daily or in a combined daily/pulse therapy 10 mg kg(-1) once daily for 28 days and then week on/week off) was reported to cure infected animals in 56-70 days. Low-dose itraconazole (1.5-3.0 mg kg(-1)) in 15-day cycles required 1-3 cycles (15-45 days). Various doses of terbinafine (5-40 mg kg(-1)) were reportedly used to treat dogs or cats. The higher doses of terbinafine (> 20 mg kg(-1)) were required to achieve a mycological cure; the number of treatment days to cure varied from 21 to > 126 days. Lufenuron was reported anecdotally to be an effective cure, however, this was not substantiated in controlled studies. Finally, fungal vaccines were not found to be effective against challenge exposure, however, there is evidence that they may be useful in treatment protocols.     

Gallbladder mucocoele and concurrent hepatic lipidosis in a cat

A 3-year-old Domestic Shorthair cat was presented with weight loss, anorexia and icterus. Feline hepatic lipidosis and gallbladder mucocoele were diagnosed; this is the first report of gallbladder mucocoele in the cat. The case was managed successfully with cholecystojejunostomy, gastrostomy tube placement and tube feeding for 3 months. The cat has survived over the long term with minimal complications.     

Ocular metastasis of a vaccine-associated fibrosarcoma in a cat

A 6‐year‐old, neutered male domestic shorthair cat was evaluated for a recurrent vaccine‐associated fibrosarcoma. The cat had three excisions of the tumour prior to presentation and was referred for radiation therapy. Ten months following treatment with radiation therapy, the cat was presented again for a cloudy appearance to the eye. An exenteration was performed, and biopsy revealed fibrosarcoma. At the same time, two discrete pulmonary nodules were identified on thoracic radiographs. Two doses of doxorubicin (20 mg/m²) and cyclophosphamide (100 mg/m²) were administered intravenously 3 weeks apart. Despite treatment, the pulmonary nodule doubled in size. This case represents the first antemortem report of ocular metastasis of a vaccine‐associated sarcoma and supports the highly aggressive nature of these tumours.     

Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis

Abstract The experimental hypothesis testéd was that dogs with generalized demodicosis have significantly lower levels of interleukin-2 (IL-2) production and IL-2 receptor expression as compared with normal dogs. The specific objective of this study was to compare the production of IL-2 and IL-2 receptor expression of peripheral blood mononuclear cells in normal dogs and dogs with generalized demodicosis. Ten dogs with juvenile-onset generalized demodicosis were evaluated. Dogs with generalized demodicosis had a significantly lower in vitro lymphocyte blastogenesis response (P < 0.006), fewer cells expressing IL-2 receptors (P < 0.03), and decreased IL-2 production (P < 0.01) than control dogs. Resumen La hipótesis experimental fue que los perros con demodicosis generalizada tienen niveles significativamente inferiores de producción y expresión de receptores de interleuquina-2 (IL-2) comparado con perros normales. El objetivo especifico de este estudio fue el de comparar le producción y expresión de receptores de IL-2 en células mononucleares de sangre periférica en perros normales y en perros con demodicosis generalizada. Se evaluaron diez perros con demodicosis generalizada iniciada en edad temprana. Los perros con demodicosis generalizada tenian in vitro una respuesta blastogénica linfocitaria inferior (P < 0.006), menos células con expresión de receptores de IL-2 (P < 0.03) y una disminución en la producción de IL-2 (p<0.01) respecto a los perros control. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis. (Evaluación de la producción y expresión de recepetores de interleuquina-2 en perros con demodicosis generalizada.) Veterinary Dermatology 1996; 7 : 213–219.] Résumé L'hypothèse expérimentale est que les chiens à démodécie généralisée présente une diminution significative du taux d'interleukine 2 (IL-2) et de l'expression des récepteurs de l'interleukine 2 comparativement à des chiens sains. L'objectif de cette étude est de comparer la production d'I12 et l'expression des récepteurs de l'IL-2 par des lymphocytes sanguins périphériques de chiens témoins et de chiens atteints de démodécie généralisée. Dix chiens avec une démodécie généralisée juvenile ont été testés. Les chiens à démodécie généralisée présentent une transformation lymphoblastique plus basse (p< 0.006), moins de cellules exprimant les récepteurs IL-2 (p<0.03) et une diminution de la production d'IL-2 (p<0.01) par rapport aux chiens témoins. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis. (Evaluation de la production d'interleukine 2 et de l'expression des récepteurs de l'interleukine 2 chez des chiens à démodécie généralisée.) Veterinary Dermatology 1996; 7 : 213–219.] Zusammenfassung Es wurde die experimentelle Hypothese getestét, daß Hunde mit generalisierter Demodikose über signifikant niedrigere Spiegel an Interieukin2-(IL-2)Produktion und IL-2-Rezeptorexpression verfügen im Vergleich zu gesunden Hunden. Der wesentilche Gegenstand dieser Untersuchung war, die Produktion von IL-2 und die IL-2Rezeptorexpression in den mononukleären Zellen des peripheren Blutes bei gesunden Hunden und solchen mit generalisierter Demodikose zu vergleichen. Zehn Hunde mit juvenilem Beginn von generalisierter Demodikose wurden untersucht. Hunde mit generalisierter Demodikose hatten eine signifikant niedrigere in vitro-Reaktion der Lymphozytenblasogenese (P < 0, 006), weniger Zellen, die IL-2Rezeptoren zeigten (P < 0,03) und eine verminderte IL-2Produktion (P < 0,01) als die Kontrollhunde. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis (Untersuchungen über die Interleukin2-Produktion und Interleukin2-Rezeptorexpression bei Hunden mit generalisierter Demodikose) Veterinary Dermatology 1996; 7 : 213–219.]     

Bilateral uveal metastasis of a subcutaneous fibrosarcoma in a cat

A 6‐year‐old neutered male domestic short‐haired cat was presented to the Comparative Ophthalmology service at Michigan State University with a 3‐week history of decreased appetite and redness of the left eye. The left forelimb had been removed 15 months previously because of the presence of a subcutaneous fibrosarcoma. In the left globe, a large iridal mass was associated with increased intraocular pressure and retinal detachment. A smaller mass involving the right iris was also present. Imaging revealed a 2‐cm mass in the left caudodorsal lung lobe, and abdominal ultrasound showed multifocal bilateral renal masses. Aspirates of these masses were nondiagnostic. The left globe was removed for palliative reasons, and histopathology showed that fibrosarcoma was infiltrating the iris, choroid, and optic nerve. Despite systemic chemotherapy with doxorubicin, the animal died 4 months after initial presentation. Histopathology confirmed highly angioinvasive metastatic fibrosarcoma also in the right uveal tract, the lungs, and both kidneys.     

Unusual presentation of a metastatic uveal melanoma in a cat

A 10 year-old, spayed female Domestic Short-Haired (DSH) cat was diagnosed with a large primary uveal melanoma and exenteration was recommended. Thoracic radiographs, abdominal ultrasonography, and complete blood count and serum biochemistry panel did not reveal any abnormality compatible with metastatic disease and surgery was performed. Histopathologic study of the eye confirmed a diffuse iris melanoma. Five months later, the cat presented with a lameness of the right anterior extremity. On physical exam the right elbow was swollen and painful. Radiographs showed a severe osteolysis of the radial head and proximal diaphysis. Fine needle aspiration of the radius head identified a round cell neoplasm with scattered cells containing intracytoplasmatic pigmented granules, compatible with metastatic melanoma. The owners decided not to treat the patient with chemotherapy and declined a biopsy. Two months later, the cat died and necropsy was performed confirming bone metastasis of the uveal melanoma. A diagnosis of generalized metastasis from primary diffuse iris melanoma was made. This report describes, for the first time, long bone metastasis from an uveal melanoma in a cat.     

Bilateral parotid duct transposition for keratoconjunctivitis sicca in a Connemara stallion

A 7‐year‐old Connemara stallion was presented with a 4 month history of blepharospasm, recurrent corneal ulcerations, mucopurulent ocular discharge, and keratoconjunctivitis sicca (KCS) in both eyes unresponsive to medical therapy. Ophthalmic examination revealed lackluster corneas, axial corneal scarring and pigmentation with associated neovascularization, and absolute KCS in both eyes. Computed tomography scan and endoscopic evaluation of the upper airway and guttural pouches revealed no structural abnormalities to indicate neurogenic KCS. The stallion was diagnosed with immune‐mediated dacryoadenitis as all other causes of KCS were excluded. Parotid duct transposition (PDT) was performed in the right eye followed by PDT in the left eye 4 weeks later. The right PDT was functional 2 years post‐operatively with significant improvement in ocular comfort and reduced corneal fibrosis and neovascularization. The left PDT developed a salivary‐cutaneous fistula over the left masseter muscle post‐operatively due to avascular necrosis of the distal parotid duct (PD). Surgical reconstruction of the PDT using an expanded‐polytetrafluoroethylene (e‐PTFE) tube graft, an e‐PTFE tube graft to autogenous caudal auricular vein graft, and an autogenous saphenous vein graft were all unsuccessful. Tear production in the left eye improved at 1 year post‐surgery as a result of long term lacrostimulant therapy, and a permanent PD‐cutaneous fistula was performed on the left PD at the level of the ventral mandible. Bilateral PDT in the horse is effective in resolving clinical signs associated with KCS; however, morbidity associated with avascular necrosis of the transposed PD may be significant and can result in surgical failure.     

Cutaneous wound healing in the cat: a macroscopic description and comparison with cutaneous wound healing in the dog

OBJECTIVE: To describe the macroscopic features of first and second intention cutaneous wound healing in the cat and compare with the dog. STUDY DESIGN: Experimental study. ANIMALS: Domestic shorthaired cats (6) and beagle dogs (6). METHODS: Square, open cutaneous wounds created on the dorsal aspect of the thorax were evaluated for 21 days for temporal and spatial development of granulation tissue, wound contraction, epithelialization, and total healing. To evaluate first intention healing, breaking strength of sutured linear cutaneous wounds was measured at 7 days post-wounding. Laser-Doppler perfusion imaging was used to measure cutaneous perfusion. RESULTS: First intention healing: sutured wounds in cats were only half as strong as those in dogs at day 7 (0.406 versus 0.818 kg breaking strength). Second intention healing: cats produced significantly less granulation tissue than dogs, with a peripheral, rather than central distribution. Wound epithelialization and total wound healing (total reduction in open wound area from contraction and epithelialization) were greater for dogs than for cats over 21 days. Wound contraction on day 7 was greater for dogs, but not on day 14 or 21. Cutaneous perfusion was initially greater for dogs than for cats, but no differences were detected after day 7. CONCLUSIONS: Significant, previously unreported differences in cutaneous wound healing exist between cats and dogs. In general, cutaneous wounds in cats are slower to heal. Cats and dogs also appear to use different mechanisms of second intention healing. In cats wounds close mainly by contraction of the wound edges, whereas in dogs wounds close more from central pull, and epithelialization. CLINICAL RELEVANCE: Surgeons should view the cat as a unique species, which presents its own special challenges in wound healing, and should take this into account when planning treatment of feline wounds, either by primary closure, or by second intention healing.     

Chylothorax associated with cryptococcal mediastinal granuloma in a cat

A 10-year-old neutered female cat had chylothorax, precaval syndrome, and a mediastinal granuloma resulting from infection with Cryptococcus neoformans. Diagnosis of a chylous effusion was made by cytologic examination of pleural fluid and by finding higher triglyceride levels in the effusion than in serum (825 vs. 64 mg/dl, respectively). Postmortem examination revealed cryptococcal organisms in the mediastinal granuloma, lungs, cerebral meninges, and connective tissues adjacent to the thyroid gland. Chylous effusion in a cat associated with cryptococcosis has not been reported previously. Cryptococcosis should be included in the differential diagnosis in chylous effusions in cats.     

Infrared ocular thermography in dogs with and without keratoconjunctivitis sicca

Infrared thermography was used to measure temperature differences of the corneal surface between nasal and temporal limbus regions and central cornea of normal dogs and dogs with keratoconjunctivitis sicca (KCS), in order to establish temperature values in normal canine eyes and in patients with decreased Schirmer tear tests (STT) values. Dogs investigated were all either patients seen at the Veterinary Teaching Hospital of Federal University of Paraná or normal dogs that belonged to the same institution. STT were performed in all eyes. A total of 40 control eyes (STT ≥15 mm/min) and 20 eyes with low STT values (STT ≤14 mm/min) were examined. The mean STT value for eyes with normal STT values was 22.9 ± 3.9 mm/min (mean ± standard deviation), and the mean STT value for eyes with low STT value was 7.2 ± 4.8 mm/min. The mean corneal temperature was significantly lower in eyes with low STT values than in control eyes (P < 0.0001). The following significant correlations were found: (i) Schirmer and breakup time (BUT) (P = 0.0001, r = 0.5); (ii) STT values and corneal surface temperature (P = 0.001, r = 0.256); (iii) STT values and age (P = 0.0001, r = ?0.448); (iv) age and corneal surface temperature (P = 0.0001, r = ?0.281); and (v) BUT and corneal surface temperature (P = 0.0001, r = 0.36). Thermography is a method that can differentiate between eyes with normal and abnormal STT values. In the future, thermography might be incorporated as part of the ophthalmic examination and perhaps become a popular ancillary test for the diagnoses of ocular surface disorders.