Julia A. Beatty

Feline pyothorax: a retrospective study of 27 cases in Australia

Pyothorax was diagnosed in 27 cats between 1983 and 2002. In 21 (78%) of the cases, pleural fluid culture and/or cytology was consistent with a mixed anaerobic bacterial infection of oropharyngeal origin. In six cases (22%), infection was caused by unusual pathogens or pathogens of non-oropharyngeal origin, including a Mycoplasma species, Cryptococcus gattii, Escherichia coli, Salmonella typhimurium and Staphylococcus aureus. The overall mortality rate was 22%. Treatment was successful in 18 of 19 cases (95%) where closed thoracostomy tubes were inserted. One case resolved only after thoracotomy. Actinomyces species were isolated in three cases and in contrast to dogs where thoracotomy is recommended, they were resolved with tube thoracostomy. Mechanical complications occurred in 58% of the cats with indwelling chest tubes. Probable mechanisms of pleural space infection were identified in 18 cats (67%) including haematogenous infection (n=1), direct inoculation of bacteria into the pleural space (n=1), intrathoracic oesophageal rupture (n=1) and parapneumonic extension of infection (n=15; 56%). Of the latter, perioperative aspiration was suspected in two cats, parasitic migration in two and antecedent upper respiratory tract infection was implicated in seven. Parapneumonic spread of infection after colonisation and invasion of lung tissue by oropharyngeal flora appears to be the most frequent cause of feline anaerobic polymicrobial pyothorax and contests the widespread belief that direct inoculation of pleural cavity by bite wounds is more common.

Low-Grade Alimentary Lymphoma: Clinicopathological Findings and Response to Treatment in 17 Cases:

Low-grade alimentary lymphoma (LGAL) was diagnosed by histological and immunohistochemical evaluation of full-thickness biopsies from multiple regions of the gastrointestinal tract collected during exploratory laparotomy in 17 cats. The most common clinical signs were weight loss (n=17) and vomiting and/or diarrhoea (n=15). Clinical signs were chronic in 11 cases. Abdominal palpation was abnormal in 12 cats, including diffuse intestinal thickening (n=8), an abdominal mass due to mesenteric lymph node enlargement (n=5) and a focal mural intestinal mass (n=1). The most common ultrasonographic finding was normal or increased intestinal wall thickness with preservation of layering. Ultrasound-guided fine-needle aspirates of mesenteric lymph nodes (n=9) were incorrectly identified as benign lymphoid hyperplasia in eight cats, in which the histological diagnosis from biopsies was lymphoma. There was neoplastic infiltration of more than one anatomic region of the gastrointestinal tract in 16/17 cats. The jejunum (15/15 cats) and ileum (13/14 cats), followed by the duodenum (10/12 cats), were the most frequently affected sites. Twelve cats were treated with oral prednisolone and high-dose pulse chlorambucil, two with a modified Madison–Wisconsin multiagent protocol and three with a combination of both protocols. Thirteen of the 17 cats (76%) had complete clinical remission with a median remission time of 18.9 months. Cats that achieved complete remission had significantly longer median survival times (19.3 months) than cats that did not achieve complete remission (n=4) (4.1 months; P=0.019). The prognosis for cats with LGAL treated with oral prednisolone in combination with high-dose pulse chlorambucil is good to excellent.

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.

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.

Suspected clindamycin-associated oesophageal injury in cats: Five cases

The clinical findings, treatment and outcome of suspected clindamycin-associated oesophageal injury in five cats are reported. All cats were treated with one 75 mg clindamycin capsule twice daily (dose range 12–19 mg/kg). Capsules were administered without food or a water bolus. Dysphagia, regurgitation, choking or gagging were seen 3–9 days after starting clindamycin. On oesophagoscopy, three cats had oesophagitis, one of which progressed to stricture formation. Two cats had an oesophageal stricture at first presentation. This is the first report of suspected clindamycin-associated oesophageal injury in cats. It serves to further alert practitioners to the potential for drug-induced oesophageal disorders (DIOD) in cats treated with oral medications and to urge prevention by promoting a change in dosing practices.

Hyperaldosteronism and Hyperprogesteronism in a Cat

Clinical findings and investigations A 14-year-old female neutered domestic shorthair cat was referred for investigation of progressive hair loss, muscle wasting and hind limb weakness. Diabetes mellitus had been diagnosed 8 months earlier and was well controlled. Abnormalities on serum biochemistry included persistent mild azotaemia, hypochloridaemia, hypokalaemia, metabolic alkalosis and elevated creatine kinase. Physical examination revealed a pot-bellied appearance, with muscle wasting, marked thinning and fragility of the skin, bilaterally symmetrical alopecia, a gallop rhythm and systolic hypertension (173 mmHg). A large, lobulated left adrenal mass was identified using abdominal ultrasound. Confirmation of diagnosis Primary hyperaldosteronism was diagnosed based on an elevated plasma aldosterone concentration and normal plasma renin activity. Hyperprogesteronism was confirmed by adrenocorticotrophic hormone stimulation test. Practical relevance This is only the second reported case of hyperaldosteronism and hyperprogesteronism in the cat. Clinicians should be alert to the possibility of concurrent hyperaldosteronism and hyperprogesteronism in cats with adrenal tumours showing clinical signs referable to both conditions. The putative mechanism is either increased secretion of aldosterone and progesterone from neoplastic cells of the zona glomerulosa and fasciculata/reticularis, respectively, or increased production of progesterone, as an intermediate in the synthesis of aldosterone, from neoplastic cells of the zona glomerulosa alone.

Novel gammaherpesviruses in North American domestic cats, bobcats and pumas: identification, prevalence and risk factors

ABSTRACT Gammaherpesviruses (GHVs) are a diverse and rapidly expanding group of viruses associated with a variety of disease conditions in humans and animals. To identify felid GHVs, we screened domestic cat (Felis catus), bobcat (Lynx rufus), and puma (Puma concolor) blood cell DNA samples from California, Colorado, and Florida using a degenerate pan-GHV PCR. Additional pan-GHV and long-distance PCRs were used to sequence a contiguous 3.4-kb region of each putative virus species, including partial glycoprotein B and DNA polymerase genes. We identified three novel GHVs, each present predominantly in one felid species: Felis catus GHV 1 (FcaGHV1) in domestic cats, Lynx rufus GHV 1 (LruGHV1) in bobcats, and Puma concolor GHV 1 (PcoGHV1) in pumas. To estimate infection prevalence, we developed real-time quantitative PCR assays for each virus and screened additional DNA samples from all three species (n = 282). FcaGHV1 was detected in 16% of domestic cats across all study sites. LruGHV1 was detected in 47% of bobcats and 13% of pumas across all study sites, suggesting relatively common interspecific transmission. PcoGHV1 was detected in 6% of pumas, all from a specific region of Southern California. The risk of infection for each host varied with geographic location. Age was a positive risk factor for bobcat LruGHV1 infection, and age and being male were risk factors for domestic cat FcaGHV1 infection. Further characterization of these viruses may have significant health implications for domestic cats and may aid studies of free-ranging felid ecology. IMPORTANCE Gammaherpesviruses (GHVs) establish lifelong infection in many animal species and can cause cancer and other diseases in humans and animals. In this study, we identified the DNA sequences of three GHVs present in the blood of domestic cats (Felis catus), bobcats (Lynx rufus), and pumas (Puma concolor; also known as mountain lions, cougars, and panthers). We found that these viruses were closely related to, but distinct from, other known GHVs of animals and represent the first GHVs identified to be native to these feline species. We developed techniques to rapidly and specifically detect the DNA of these viruses in feline blood and found that the domestic cat and bobcat viruses were widespread across the United States. In contrast, puma virus was found only in a specific region of Southern California. Surprisingly, the bobcat virus was also detected in some pumas, suggesting relatively common virus transmission between these species. Adult domestic cats and bobcats were at greater risk for infection than juveniles. Male domestic cats were at greater risk for infection than females. This study identifies three new viruses that are widespread in three feline species, indicates risk factors for infection that may relate to the route of infection, and demonstrates cross-species transmission between bobcats and pumas. These newly identified viruses may have important effects on feline health and ecology.

Hypereosinophilic paraneoplastic syndrome in a cat with intestinal T cell lymphosarcoma

A 10‐year‐old, neutered female, domestic shorthair cat was presented with a recent history of weight loss, polydipsia, diarrhea and vomiting. On physical examination, intestinal thickening and mesenteric lymph node enlargement were apparent. Clinical investigations revealed peripheral blood eosinophilia, eosinophilic abdominal effusion and eosinophilic mesenteric lymphadenitis. There was a temporary response to treatment with glucocorticoids but signs progressed and the cat was euthanased. On histology, there was eosinophilic infiltration and fibroplasia of intestine and mesenteric lymph nodes. Large aggregates of neoplastic round cells in the intestine and lymph nodes were identified as T lymphocytes using immunohistochemistry. A diagnosis of intestinal T cell lymphosarcoma was made. This case demonstrates that hypereosinophilic paraneoplastic syndrome may occur in cats with lymphosarcoma. Eosinophil chemotaxis may be a response to the production of interleukin‐5 by neoplastic lymphocytes.

Feline alimentary lymphoma 1. Classification, risk factors, clinical signs and non-invasive diagnostics

Practical relevance Alimentary lymphoma (AL) occurs commonly in cats and exists as distinct subtypes that differ in their clinical course, response to treatment and prognosis. Accurate diagnosis is important to guide appropriate treatment. Clinical challenges Differentiation of low-grade alimentary lymphoma from lymphoplasmacytic enteritis can be challenging, especially where endoscopic intestinal biopsies, which sample only the mucosa and submucosa, are used. The major differentials for intermediate- and high-grade alimentary lymphoma are other neoplastic and non-neoplastic intestinal mass lesions. The diagnosis of large granular lymphocyte lymphoma requires vigilance as it may be missed with routine diagnostics. Patient group AL affects predominantly middle- to old-aged domestic crossbred cats (median age 10–13 years). Evidence base The evidence supporting this review is grade II, III and IV, derived from prospective studies, retrospective case series, reviews, extrapolation from other species, pathophysiological justification and the combined clinical experience of those working in the field.

Peripheral vestibular disease associated with cryptococcosis in three cats.

Peripheral vestibular disease referable to otitis media/interna was the main reason for presentation in three cats with cryptococcosis. In two cats, Cryptococcus neoformans var neoformans was isolated from the tympanic bulla. In the remaining cat, otitis media/interna was considered to be secondary to occlusion of the auditory tube by a nasopharyngeal granuloma associated with a C neoformans var gattii infection. This report emphasises the importance of maintaining an index of suspicion for a fungal aetiology in cats with signs of otitis media/interna, particularly in countries with a high prevalence of cryptococcosis. The presence of C neoformans may be overlooked with potentially fatal consequences where only standard methods for bacterial isolation are used to examine samples obtained from the middle ear.