Journal of Feline Medicine and Surgery

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.

An abdominal mass was identified upon palpation of the abdomen in a normal, asymptomatic, 1-year-old female domestic shorthair cat presented for elective ovariohysterectomy. Radiographic and ultrasound examinations demonstrated a well-circumscribed caudal abdominal mass. Ultrasound guided needle aspiration cytology was consistent with an accumulation of squamous epithelial cells. The mass was associated with the jejunum and was excised via resection anastomosis of the intestinal segment after ovariohysterectomy. Histologic examination provided the diagnosis of an intestinal duplication lined with epithelium typical of that in the esophagus. The cat recovered without complications.

A 10-year-old male castrated domestic shorthair cat was evaluated for coughing and lethargy. Thoracic radiographs revealed a soft tissue lung mass and diffuse peribronchial infiltrates. Bronchoscopy was performed and Capnocytophaga cynodegmi was cultured from bilateral bronchoalveolar lavage samples. Clinical signs and bacterial colonization resolved following treatment with enrofloxacin. A lung lobectomy was performed to remove the lung mass, which was diagnosed as pulmonary carcinoma. C cynodegmi is most frequently isolated from localized wound and corneal infections in humans. Specialized growth characteristics of C cynodegmi may result in low sensitivity for bacterial culture. To the authors' knowledge, this case represents the first report of C cynodegmi infection in a veterinary patient and only the second case in human or veterinary medicine where the organism has been isolated from a bronchoalveolar lavage sample. Based on this report, Capnocytophaga species should be considered as potential opportunistic pathogens.

This report describes a clinical case of feline infectious peritonitis (FIP) with multisystemic involvement, including multiple nodular cutaneous lesions, in a cat that was co-infected with feline coronavirus and feline immunodeficiency virus. The skin lesions were caused by a pyogranulomatous-necrotising dermal phlebitis and periphlebitis. Immunohistology demonstrated the presence of coronavirus antigen in macrophages within these lesions.

The pathogenesis of FIP involves a viral associated, disseminated phlebitis and periphlebitis which can arise at many sites. Target organs frequently include the eyes, abdominal organs, pleural and peritoneal membranes, and central nervous tissues, but cutaneous lesions have not previously been reported.

An 11-year-old cat was presented with an approximately 2-month history of dysphagia, intermittent regurgitation and weight loss. An oesophageal foreign body was identified on plain radiographs, and an oesophagotomy was performed to remove a large V-shaped bone from the caudal cervical oesophagus. A gastrostomy feeding tube was placed to allow nutritional support postoperatively. Medical treatment for oesophagitis was initiated after surgery. No complications were encountered and the cat was discharged 4 days after surgery.