Pneumomediastinum, pneumothorax and pneumoretroperitoneum following endoscopic retrieval of a tracheal foreign body from a cat

A 6-year-old entire male cat was presented with a 1-week history of severe dyspnoea without coughing. Upon auscultation, an inspiratory and particularly pronounced expiratory wheeze was noted, with severe dyspnoea. The minimum database was normal. Plain thoracic radiographs showed signs of a mural or intraluminal intrathoracic (T1-T4) tracheal narrowing. A dynamic collapsing trachea was ruled out using fluoroscopy. Bronchoscopy was performed and a dark green and brown spiculated foreign object was found just cranial to the carina. Following removal, the cat rapidly developed extensive truncal subcutaneous emphysema and oxygen-responsive dyspnoea and cyanosis. Follow-up radiographs demonstrated unilateral pneumothorax and lung collapse, marked pneumomediastinum and dissection of air through the tracheal wall. A thoracic drain was placed and the pneumothorax resolved rapidly. Follow-up radiographs demonstrated resolution of pneumothorax and development of extensive retroperitoneal air. The cat made an uneventful recovery. The foreign object was the calyx and stem of a flower. This article emphasises the importance of diagnostic imaging in the dyspnoeic patient, both for confirming initial suspicions of respiratory tract disease, and in managing and charting post-therapy resolution or complications.     

Vincristine overdose in a cat: clinical management, use of calcium folinate, and pathological lesions

A 6-year-old female neutered Burmese cat received a 10 times overdose (5mg/m(2)) of vincristine, administered in error. Supportive therapy, including administration of calcium folinate, was instigated within 8h. Despite treatment, the patient exhibited deterioration in renal and respiratory function and died 72 h after overdose. Necropsy was performed within 24h of death. Gross examination revealed pulmonary oedema and a pale brown liver with a prominent lobular pattern. Histological examination revealed marked apoptosis and necrosis of the bone marrow myeloid series, and mild to moderate apoptosis and necrosis of the erythroid and megakaryocyte series. Multifocal necrosis of the renal tubules, hepatocytes, and small intestinal crypt epithelium was also observed. Use of calcium folinate as a rescue therapy following vincristine overdose in humans has been previously documented. If treatment is to be successful in cases of vincristine overdose in cats, then a more complete understanding of the pathogenesis of vincristine toxicity in companion animal species is required.     

Gastric dilatation-volvulus associated with diaphragmatic hernia in three cats: clinical presentation, surgical treatment and presumptive aetiology

Three cats were examined because of acute dyspnoea and sudden abdominal enlargement. In all cats, radiographs revealed gastric dilatation-volvulus (GDV) and diaphragmatic hernia. Cardiovascular shock and dyspnoea were treated by intravenous fluid-therapy, oxygen administration and relief of diaphragmatic pressure by means of stomach decompression and in one case placing the patient in an inclined position. Gastric decompression was performed by needle gastrocentesis, placement of a rhino-gastric tube, or a combination of these. Diaphragmatic herniorrhaphy was performed in either case; one cat also underwent gastropexy. The immediate postoperative period resolved uneventfully and the cats were doing well at follow-up. Feline GDV is a rare event in which diaphragmatic hernia may be a predisposing factor.     

Aortic body chemodectoma causing pulmonary oedema in a cat

A seven-year-old male domestic shorthaired cat was presented with persistent dyspnoea. Thoracic radiography and echocardiography revealed pulmonary oedema and a mass at the base of the heart. At necropsy the mass was found to be an aortic body chemodectoma that had metastasised to the sternal lymph node. This is a rare tumour in the cat, the third reported case where there was evidence of metastasis, and only the second reported case where there was evidence of lymphocytic infiltration of the primary tumour. Pulmonary oedema is an unusual presentation of this tumour in the cat.     

Unilateral laryngeal paralysis in a cat

A case of unilateral laryngeal paralysis in a cat is described which presented with signs of nasal discharge and dyspnoea. The condition is compared with laryngeal paralysis as seen in the horse and dog.     

Hepatic cysts incarcerated in a peritoneopericardial diaphragmatic hernia

Peritoneopericardial diaphragmatic hernia is a common incidental finding in cats and is rarely symptomatic. The case report described herein presented with dyspnoea secondary to incarceration of hepatic cysts within the pericardial space of a cat with a peritoneopericardial diaphragmatic hernia.     

Pulmonary adenocarcinoma with osteoblastic bone metastases in a cat

A 12-year-old male cat with depression and dyspnoea was presented for investigation. Radiography and computed tomography revealed hydrothorax and solid masses involving the sternum, ribs and thoracic vertebrae. The cat died two days after first presentation, and postmortem examination revealed lung masses and proliferative bony lesions. Histologically, a neoplastic proliferation of epithelial cells was seen in the lungs, with a large amount of collagen and deposits of cholesterin. The bone lesions were also composed of neoplastic epithelial cells and abundant calcified osteoid, without atypia. A diagnosis of pulmonary adenocarcinoma with osteoblastic bone metastases was made. This is the first reported case of osteoblastic metastases in the cat.     

Pustular calicivirus dermatitis on the abdomen of two cats following routine ovariectomy

An unusual form of calicivirus dermatitis is described in two cats. Two fully vaccinated cats were re-admitted for anorexia and depression following routine ovariectomy. Signs of upper respiratory disease were not present. One cat subsequently showed painful necrosis of the incision wound, the other one developed dyspnoea with pleural effusion and discrete tongue ulcers. Intact pustular lesions confined to the surgically prepared abdomen appeared in both cats, respectively, on days 11 and 9. The histopathological diagnosis was panepidermal pustulosis and necrotizing dermatitis. Positive immunohistochemical staining consistent with feline calicivirus antigen was detected in epithelial cells within pustular lesions. The cats were treated with antibiotics and ketoprofen. The cat with progressive dyspnoea was euthanized. The clinical signs in the other cat rapidly and completely resolved following glucocorticoid therapy. It is hypothesized that the reported cases may represent a distinct calicivirus-induced pustular dermatitis following ovariectomy.     

Nasal myiasis in a cat caused by larvae of the nasal bot fly, Oestrus ovis

An 8-year-old desexed male Burmese cat, which lived on a sheep-grazing property in central New South Wales, Australia, was presented following the sudden onset of dyspnoea, moist coughing and violent sneezing. The respiratory distress started several hours after the cat had made an outdoor excursion. Anterior rhinoscopy demonstrated small, white objects moving across oedematous and moderately inflamed nasal mucosa. These were retrieved via a series of vigorous nasal flushes and subsequently identified as larvae of the nasal bot fly, Oestrus ovis. The cat was treated with ivermectin followed by selamectin 7 days later. It went on to make a complete recovery over 2-3 weeks.     

Caudal mediastinal thyroglossal duct cyst in a cat

An eight-year-old domestic shorthair cat was evaluated because of dyspnoea secondary to pleural effusion. Ultrasound examination identified a large anechoic cyst-like structure in the caudal thorax. A median sternotomy was performed, and the cystic mass was removed. Microscopically, the excised tissue was identified as a multilocular thyroglossal duct cyst with ectopic thyroid tissue. To the authors' knowledge, this is the first report of a mediastinal thyroglossal duct cyst in a cat. Despite the rarity of this lesion, it should be considered when a cystic thoracic structure is identified on thoracic ultrasound. Surgical excision of the cyst resulted in complete resolution of the pleural effusion and clinical signs.     

Caudal mediastinal abscess due to a grass awn (Hordeum spp) in a cat

A two-and-a-half year-old male, domestic shorthaired cat was presented with a history of chronic expiratory dyspnoea, dysphagia and progressive weight loss. Thoracic radiography revealed a caudal mediastinal mass. Surgical exploration confirmed the presence of an abscess in the caudal mediastinum. Despite the good prognosis, euthanasia was performed at the owner's request and post-mortem examination revealed an abscess that had been caused by a grass awn located within.     

Acute monocytic leukaemia in a cat

A three-year-old cat with lymphadenopathy, non-regenerative anaemia and marked leucocytosis (171.3 x 10(9) white blood cells/l) was diagnosed with monocytic leukaemia and treated with a combination of anticancer drugs. A number of mature and immature monocyte-like cells were detected in the peripheral blood and bone marrow; they proved to be monocytic cells by cytochemical examination and an analysis of their cell surface phenotype, indicating that the cat suffered from acute myeloid leukaemia, subclassified as monocytic leukaemia (M5). Treatment with cytarabine, doxorubicin, vincristine and prednisolone greatly reduced the number of blast cells in the cat's peripheral blood and bone marrow. The cat was in partial remission for 67 days and survived for 95 days after it was first examined.     

Heart failure due to atrial standstill in a cat

A 7.5-year-old male Persian cat with a history of asymptomatic hypertrophic cardiomyopathy was examined for severe lethargy and dyspnoea. Physical examination revealed bradycardia (60 beats/ minute), and ECG investigation revealed persistent atrial standstill that was most likely caused by atrial fibrosis. Persistent atrial standstill is a very rare cardiac condition in cats and is characterized by a complete lack of mechanical, electrical, and possibly endocrine function of the atria. Several pathophysiological mechanisms can cause atrial standstill and include hyperkalaemia, intoxication, and atrialfibrosis. On the basis of the clinical findings, atrial fibrosis was the most likely cause of atrial standstill in this cat. Treatment depends on the underlying cause, but pacemaker implantation can be considered if there are structural abnormalities. The prognosis is guarded in such cases. In this particular case, the cat was euthanized at the owner's request.     

Dyspnoea and pulmonary consolidation in a cat with T-cell lymphoma

A 13-year-old male neutered domestic shorthair cat presented with an acute onset of dyspnoea. Thoracic radiographs revealed marked, bilateral, caudal lung lobe consolidation. A diagnosis of anatomically mixed T-cell lymphoma with pulmonary, renal and alimentary involvement was confirmed on histopathology. Pulmonary involvement in cases of feline lymphoma is uncommon and the radiographic appearance of pulmonary lymphoma is highly variable. Lung lobe consolidation has been described with primary lung tumours in cats, but not previously in association with pulmonary lymphoma. This unusual presentation serves to alert practitioners to the possibility of lymphoma as a cause of severe bronchopulmonary disease in the cat.     

Diagnosis of pulmonary thromboembolism in a cat using echocardiography and pulmonary scintigraphy

A 10-year-old male cat was presented with sudden onset of respiratory difficulties. Clinical examinatlon revealed an acute dyspnoea with cyanosis associated with a left systolic heart murmur. Standard thoracic radiographs excluded pulmonary oedema and showed very few pulmonary changes given the intensity of the respiratory compromlse. Echocardiographic examination revealed hypertrophic cardiomyopathy and a thrombus In the right pulmonary artery. Pulmonary sclntlgraphy confirmed a pulmonary thromboembolism with hypovascularisatlon of the left cranial lobe and of the ventral segment of the right lobe. Conservative treatment was instituted using an antibiotic (doxycycllne), anticoagulants (heparin, coumadine) and a calcium lnhlbitor (diltiazem). The cat was given absolute rest. The general condition of the animal improved.     

Syncope associated with paroxysmal atrioventricular block an ventricular standstill in a cat

A four-and-a-half-year-old neutered male shorthair cat was presented with a three-week history of episodic fainting. Twenty-four hour electrocardiographic (Holter) recording revealed frequent prolonged episodes of complete atrioventricular (AV) block with ventricular standstill. The fainting episodes coincided with the longest periods of ventricular inactivity. A permanent transjugular pacemaker was placed to prevent further life-threatening episodes of syncope. Three months after discharge, the patient was re-presented with sudden onset dyspnoea associated with chylothorax and electrocardiography showed a third degree (complete) AV block. The pacemaker was reprogrammed in view of the third degree AV block and the chylous effusion was successfully treated by repeated thoracocentesis and long-term diuresis. However, the patient's general condition deteriorated progressively and the cat was euthanased five and a half months after implantation of the pacemaker.     

Bromide-associated lower airway disease: a retrospective study of seven cats

Seven cats were presented for mild-to-moderate cough and/or dyspnoea after starting bromide (Br) therapy for neurological diseases. The thoracic auscultation was abnormal in three cats showing increased respiratory sounds and wheezes. Haematology revealed mild eosinophilia in one cat. The thoracic radiographs showed bronchial patterns with peribronchial cuffing in most of them. Bronchoalveolar lavage performed in two cats revealed neutrophilic and eosinophilic inflammation. Histopathology conducted in one cat showed endogenous lipid pneumonia (EnLP). All cats improved with steroid therapy after Br discontinuation. Five cats were completely weaned off steroids, with no recurrence of clinical signs. In one cat, the treatment was discontinued despite persistent clinical signs. The cat presenting with EnLP developed secondary pneumothorax and did not recover. Br-associated lower airway disease can appear in cats after months of treatment and clinical improvement occurs only after discontinuing Br therapy.     

Hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia in a cat

Hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia was diagnosed in an 11-year-old, desexed female Persian cat. The cat was initially referred for investigation of tachypnoea and dyspnoea. Peritoneopericardial diaphragmatic hernia is a common incidental finding in cats and is usually asymptomatic. Myelolipoma is an extremely rare benign tumour, composed of extramedullary haematopoietic cells and adipose tissue. Myelolipomas are hypothesised to result from metaplastic alteration, rather than a neoplastic process, although this theory cannot be substantiated. The present case is only the fourth report of such an unusual occurrence in cats and displays significant differences to previous reports. Hepatic entrapment and burgeoning of the mass within the pericardial sac resulted in cardiac tamponade and overt signs of right-sided cardiac failure. Surgical intervention was successful and despite concerns regarding the cat's clinical presentation and the gross appearance of the lesion(s), a good long-term outcome is anticipated.     

Successful surgical management of a perforating oesophageal foreign body in a cat

CASE PRESENTATION AND SURGICAL INTERVENTION: a 3-year-old cat was presented with a recent history of dysphagia and intermittent regurgitation. Radiography revealed a bony oesophageal foreign body at the level of the thoracic inlet. Endoscopic retrieval was attempted but resulted in severe dyspnoea due to the development of pneumomediastinum, pneumothorax and subcutaneous emphysema secondary to perforation of the oesophageal wall. Immediate surgical exploration was carried out. Extensive necrosis of the oesophagus resulting from the presence of the foreign body led to a decision to perform an oesophageal resection and anastomosis. CLINICAL RELEVANCE: this is the first clinical report of a cat treated successfully by oesophagectomy following oesophageal perforation due to an obstructive foreign body. The authors suggest that prompt surgical intervention, the ability to convert to a surgical procedure under the same anaesthetic as a non-surgical retrieval, placement of a gastrostomy tube and the availability of advanced anaesthetic and critical care support are important factors to consider when managing feline patients with a perforating oesophageal foreign body.