Associations between increased body condition score, bodyweight, age and breed with urethral obstruction in male castrated cats.

Identifying potential risk factors for urethral obstruction in male cats may help in disease prevention. The aims of this study were to assess whether breed, pedigree status, age, bodyweight and body condition score (BCS) are risk factors for urethral obstruction in castrated male cats using a primary care population. Within this, a specific question was whether any increase in rate of urethral obstruction in male cats due to excess body condition is because of higher bodyweight. A retrospective hospital-based matched case-control study was performed using 195 cases of urethral obstruction in castrated male cats and 195 control consultations for cats presenting to a feline-only first opinion veterinary practice in Brisbane, Australia. The incidence rate of urethral obstruction did not vary significantly with bodyweight but increased with BCS (incidence rate ratio 1.6; 95% CI 1.2-2.1; P<0.001). The effect of BCS was not due to high BCS cats having higher bodyweights. The incidence was lower in Burmese cats compared to Domestic shorthair cats (incidence rate ratio 0.1; 95% CI 0.0-0.4; P=0.001), and higher in non-pedigree cats compared to pedigree cats (incidence rate ratio 2.8; 95% CI 1.7-4.6; P<0.001). Incidence rate ratios increased with age to 2 to 4years (the ages with highest incidences) then progressively declined with each additional year of age. Further research is needed to define why there is a positive association between BCS and rate of urethral obstruction. In the interim, clinicians should encourage owners of castrated male pet cats to ensure their cat's BCS is not high.

Sinonasal and sino-orbital aspergillosis in 23 cats: aetiology, clinicopathological features and treatment outcomes.

Aetiology, clinicopathological findings and treatment outcomes were documented in 23 cats (1.5-13 years of age) with sinonasal (SNA, n=6) or sino-orbital (SOA, n=17) aspergillosis. Cases recruited retrospectively and prospectively were included if fungal hyphae were identified on cytological or histological examination and the fungal pathogen was identified by PCR and DNA sequencing (ITS1 or ITS1-5.8S-ITS2 regions, rDNA gene cluster). Fungal culture was positive in 22/23 cases. In cases of SNA, the fungal pathogen was Aspergillus fumigatus (n=4), Neosartorya fischeri or A. lentulus (n=1) or a non-speciated Neosartorya spp. (n=1). In all cases of SOA (n=17), the fungal pathogen was identified as Neosartorya spp. Nine cats had brachycephalic conformation. Cats with SNA were more likely to be infected with A. fumigatus and had a better prognosis than cats with SOA.

Fatal venous air embolism in a cat undergoing dental extractions.

A five-year-old domestic shorthair cat underwent general anaesthesia and tooth extractions. Immediately after use of a high-speed, air-driven, water-cooled dental drill, the cat suffered cardiac arrest and attempted resuscitation was unsuccessful. Post-mortem radiographs showed air in the vena cava, right atrium, right auricle and right ventricle, hepatic and renal veins. These findings were confirmed at post-mortem examination. The cause of death was massive air embolism. There are reports of fatal venous air embolism in the human literature from the use of high-speed, air-driven, water-cooled dental drills. In this case, we believe that the air jet from the cooling system provided an enormous pressure gradient allowing air entry through an alveolar bone fracture or the inflamed gingival tissues. This is the first report of fatal venous air embolism associated with the use of a high-speed dental drill in the veterinary literature.

Nocardia infections in cats: a retrospective multi-institutional study of 17 cases.

OBJECTIVE: To record 17 cases of nocardiosis in cats from eastern Australia and to compare this series with cases previously reported. DESIGN: Retrospective/prospective study. RESULTS: Nocardia spp infections were diagnosed in 17 cats over 14 years from the three eastern states of Australia. There were no isolates from dogs during this period, but one isolate from a koala and two from dairy cows. The majority of cats presented with spreading lesions of the subcutis and skin associated with draining sinus tract(s). Early cutaneous lesions consisted of circumscribed abscesses. Infections spread at a variable rate, generally by extension to adjacent tissues. Lesions were generally located in regions subjected to cat bite or scratch injuries, including limbs, body wall, inguinal panniculus and nasal bridge. In some other cases, lesions were situated on distal extremities. The clinical course was variable, from chronic, indolent, initially localised infections to acute fulminating disease. Of the 17 cats, 14 were domestic crossbreds and three were purebreds. There was a preponderance of male cats (12 castrated, 1 entire young adult, 1 entire kitten). Nine of 17 cats were 10 years or older. Interestingly, the majority of infections were attributable to N nova. Immediate and/or predisposing causes could be identified in all cases, and included: renal transplantation [one cat]; chronic corticosteroid administration [three cats]; catabolic state following chylothorax surgery [one cat]; fight injuries [seven cats]; FIV infections [three of seven cats tested]. Of the 17 cats, three were apparently cured. Four were thought to be cured, but infection recurred after several months. Three cats responded partially but were euthanased, while another was improving when it died of unrelated complications. Two died despite treatment and two were euthanased without an attempt at therapy. For two cats there were either insufficient records or the patient was lost to follow up. CONCLUSION: Nocardiosis is a rare, serious disease. Currently it is more common in cats than dogs. Nocardial panniculitis may be clinically indistinguishable from the syndrome caused by rapidly growing mycobacteria. Although the prognosis is guarded, patients with localised infections caused by N nova often respond to appropriate therapy. If definitive treatment is delayed because of misdiagnosis, the disease tends to become chronic, extensive and refractory. Insufficient duration of therapy leads to disease recurrence.

Prevalence of autosomal dominant polycystic kidney disease in Persian cats and related-breeds in Sydney and Brisbane.

OBJECTIVE: A form of autosomal dominant polycystic kidney disease has been identified in Persian cats and related breeds. Two features make elimination of this disease from future generations an achievable goal: the autosomal dominant mode of inheritance and the availability of a noninvasive technique, renal ultrasonography, to identify affected cats. The aims of this study were; to determine the prevalence of the disease in Persian cats and related breeds in Sydney and Brisbane, to determine any effect of domicile and breed on disease prevalence, to alert veterinary practitioners to the prevalence of autosomal dominant polycystic kidney disease and to propose methods of eliminating the disease from future generations of cattery-bred cats. DESIGN: To be included in this scheme, cats had to be of Persian or related breed and be older than 10 months-of-age. Younger cats were excluded because of the increased likelihood of a false negative result. Renal ultrasonography was performed using either a Medison 600 with a 7.5 MHz mechanical sector scanner (n = 228, Brisbane) or using an ATL UltraMark-9 with a 5 to 10 MHz linear array transducer (n = 92, Sydney). The effects of domicile (Sydney versus Brisbane) and breed on the prevalence of autosomal dominant polycystic kidney disease were tested using two-tailed Fisher's Exact tests. RESULTS: A total of 320 cats were tested comprising 230 Persians, 48 Himalayans, 17 Exotics, 14 Burmillas, 6 Ragdolls and 5 Chinchillas. The prevalence of autosomal dominant polycystic kidney disease in Sydney (45%) and Brisbane (42%) was comparable and no sex predilection was identified. The disease was not detected in Ragdolls, although only a small number was tested. Two of 14 Burmilla cats were positive (14%), demonstrating that long hair coat and brachycephalic features do not segregate with the polycystic kidney disease trait. CONCLUSION: These results show that the prevalence of autosomal dominant polycystic kidney disease amongst purebred, long-haired cats in Australia is currently very high. Ultrasound detection schemes are easy to establish and breeder participation can be encouraged through subsidisation.

Intestinal obstruction by trichobezoars in five cats.

Between 1997 and 1999, five domestic crossbred cats (four long haired, one short haired) presented with a palpable abdominal mass and were shown to have small intestinal trichobezoars at laparotomy or necropsy. Hair balls were associated with partial or complete intestinal obstruction and were situated in the proximal jejunum to distal ileum. In four cats obstructions were simple, while the remaining cat had a strangulating obstruction. Three of the cats were 10 years or older, and two were less than 4 years. In the three older cats abdominal neoplasia was suspected and investigations were delayed or declined in two of these cats because of a perceived poor prognosis. Predisposing factors identified in this series of cats included a long-hair coat, flea allergy dermatitis, inflammatory bowel disease and ingestion of non-digestible plant material. This report shows that the ingestion of hair is not always innocuous and that intestinal trichobezoars should be considered in the differential diagnoses of intestinal obstruction and intra-abdominal mass lesions, particularly in long-haired cats.