Pyothorax in nine dogs

The results of treatment of pyothorax using systemic antibiotics, drainage, and lavage of the pleural space, are reported for 9 dogs. All 9 dogs recovered completely. In 8 of the 9 dogs the follow-up period was at least 6 months and in none was there a relapse. The results obtained with this treatment are excellent in comparison with the results that have been reported for treatment with systemic antibiotics and drainage of the pleural space but without lavage. Apart from the addition of pleural lavage to the treatment protocol, the better result might be because migrating plant related foreign bodies did not seem to play an important role in the pathogenesis of pyothorax in this group of dogs.     

Spirocercosis-associated pyothorax in dogs

The records of five dogs diagnosed with spirocercosis-associated pyothorax were retrospectively reviewed. On admission, the most common clinical findings were weakness, anorexia, depression, dyspnoea and fever. All dogs had typical oesophageal Spirocerca lupi granulomas. Contrast thoracic radiography revealed contrast material leakage from the oesophagus into the pleural cavity in two dogs only. All dogs were medically treated with broad-spectrum antibiotics, repeated chest tube drainage and thoracic lavage, and four of the dogs were treated with doramectin. One dog was euthanased due to a concurrent non-related disease at the owners request while the remaining four survived. S. lupi infection should be included in the differential diagnoses of canine pyothorax in endemic areas. Conservative medical management of pyothorax with antihelmintic medication was shown to be effective in the treatment of S. lupi-associated pyothorax.     

Feline pyothorax - new insights into an old problem: part 2. Treatment recommendations and prophylaxis

Until recently, pyothorax in the cat has been generally considered to have a poor prognosis. However, it has become clear that most cats that survive the first 48 h following presentation can be successfully treated with aggressive medical management. In this second part of a two-part review, logical guidelines for the management of the disease are discussed, with particular emphasis on antimicrobial selection. Patient stabilisation and supportive care, techniques for pleural space drainage and lavage and indications for surgery are reviewed.     

Canine and feline pyothorax: a retrospective study of 50 cases in the UK and Ireland

Fifty cases (36 dogs and 14 cats) with a confirmed diagnosis of pyothorax were evaluated from five referral institutions in the UK and Ireland. Aetiology, clinical presentation, diagnosis, treatment and outcome of all cases were examined. The underlying cause of pyothorax was determined in 18 per cent of cases. Positive bacteriological cultures of the pleural fluid were obtained in 68.7 per cent of the animals. Treatment modalities included surgery and medical management, involving thoracostomy tube placement, thoracic aspiration, thoracic lavage and antimicrobial therapy. A successful outcome was achieved in 86 per cent of patients.     

Medical and surgical treatment of pyothorax in dogs: 26 cases (1991-2001)

OBJECTIVE: To compare outcomes of dogs with pyothorax treated medically versus surgically and to identify prognostic indicators for dogs with pyothorax. DESIGN: Retrospective study. ANIMALS: 26 dogs. PROCEDURE: Medical records were reviewed to obtain information regarding signalment, results of physical and laboratory evaluations at the time of initial examination, results of bacterial culture of pleural fluid, radiographic abnormalities, treatment (surgical vs medical), complications, whether the disease recurred, disease-free interval, survival time, and cause of death. RESULTS: Calculated proportions of dogs free from disease 1 year after treatment were 25 and 78%, respectively, for dogs treated medically and surgically. Treatment was 5.4 times as likely to fail in dogs treated medically as in dogs treated surgically. Two regression models relating treatment group (medical vs surgical) to disease-free interval were found to be significant. The first contained terms for medical treatment and isolation of Actinomyces spp from pleural fluid; the second contained terms for medical treatment and radiographic detection of mediastinal or pulmonary lesions at the time of initial examination. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that surgical treatment is associated with a better outcome than medical treatment in dogs with pyothorax. In addition, surgery should be considered if radiographic evidence of mediastinal or pulmonary lesions is detected or if Actinomyces spp is isolated from the pleural fluid.     

Nodules and masses are associated with malignant pleural effusion in dogs and cats but many other intrathoracic CT features are poor predictors of the effusion type

Thoracic CT may be used in the workup of patients with pleural effusion. In humans, certain pleural features on CT aid in diagnosing an underlying cause for pleural effusion, whereas this is not well studied in veterinary medicine. This retrospective cross‐sectional analytical study assessed pleural and other intrathoracic abnormalities on CT in dogs and cats with pleural effusion and explored potential discriminatory features between effusion types. Eighty‐nine dogs and 32 cats with pleural cytology and/or histopathology were categorized into malignant pleural disease (15 dogs and 11 cats), pyothorax (34 dogs and 7 cats), chylothorax (20 dogs and 11 cats), transudative (11 dogs and 2 cats), and hemorrhagic effusion (9 dogs and 1 cat). Multivariable logistic regression analysis comparing malignancy to other effusions found that older patient age (dogs: odds ratio 1.28, P = 0.015; cats: odds ratio 1.53, P = 0.005), nodular diaphragmatic pleural thickening (dogs: odds ratio 7.64, P = 0.021; cats: odds ratio 13.67, P = 0.031), costal pleural masses (dogs: odds ratio 21.50, P = 0.018; cats: odds ratio 32.74, P = 0.019), and pulmonary masses (dogs: odds ratio 44.67, P = 0.002; cats: odds ratio 18.26, P = 0.077) were associated with malignancy. In dogs, any costal pleural abnormality (odds ratio 47.55, P = 0.002) and pulmonary masses (odds ratio 10.05, P = 0.004) were associated with malignancy/pyothorax, whereas any costal pleural abnormality (odds ratio 0.14, P = 0.006) and sternal lymphadenopathy (odds ratio 0.22, P = 0.040) were inversely associated with transudates. There were, however, many overlapping abnormalities between effusion types, so further diagnostic testing remains important for diagnosis.     

Successful medical treatment of 15 dogs with pyothorax

OBJECTIVES: To review the success of non-surgical management, which included antibiotics and a single thoracocentesis, in 15 dogs presenting with pyothorax. METHODS: Sixteen dogs were selected retrospectively from case files at the Veterinary Cardiorespiratory Centre. RESULTS: One dog was diagnosed with a mass suspected to be a pulmonary abscess on ultrasound examination and was referred for surgery. Fifteen dogs were treated medically. Springer spaniels were the most commonly presented breed (six cases) followed by Labrador retrievers (three cases). Under sedation or general anaesthesia, thoracocentesis was performed unilaterally and as much purulent effusion as possible was removed. Lavage of the thorax was not undertaken. In most dogs, antibiotic treatment was ampicillin at a mean dose of 33 mg/kg administered three times daily and 25 mg/kg metronidazole administered twice daily. Antibiotics were provided for a minimum of six weeks. All dogs recovered completely and did not show relapse on prolonged follow-up. This included one dog, which had very widespread pleural adhesions and minimal effusion. CLINICAL SIGNIFICANCE: In dogs that do not have evidence of pulmonary masses or consolidations and no evidence of granular pleural effusion, medical therapy may be curative even in chronic cases of pyothorax with pleural adhesions.     

Can malignant and inflammatory pleural effusions in dogs be distinguished using computed tomography?

Computed tomography (CT) is the primary imaging modality used to investigate human patients with suspected malignant or inflammatory pleural effusion, but there is a lack of information about the clinical use of this test in dogs. To identify CT signs that could be used to distinguish pleural malignant neoplasia from pleuritis, a retrospective case‐control study was done based on dogs that had pleural effusion, pre‐ and postcontrast thoracic CT images, and cytological or histopathological diagnosis of malignant or inflammatory pleural effusion. There were 20 dogs with malignant pleural effusion (13 mesothelioma, 6 carcinoma; 1 lymphoma), and 32 dogs with pleuritis (18 pyothorax; 14 chylothorax). Compared to dogs with pleuritis, dogs with malignant pleural effusions were significantly older (median 8.5 years vs. 4.9 years, P = 0.001), more frequently had CT signs of pleural thickening (65% vs.34%, P = 0.05), tended to have thickening of the parietal pleura only (45% vs. 3%, P = 0.002) and had more marked pleural thickening (median 3 mm vs. 0 mm, P = 0.03). Computed tomography signs of thoracic wall invasion were observed only in dogs with malignant pleural effusions (P = 0.05). There were no significant differences in pleural fluid volume, distribution or attenuation, degree of pleural contrast accumulation, amount of pannus, or prevalence of mediastinal adenopathy. Although there was considerable overlap in findings in dogs with malignant pleural effusion and pleuritis, marked thickening affecting the parietal pleural alone and signs of thoracic wall invasion on CT support diagnosis of pleural malignant neoplasia, and may help prioritize further diagnostic testing.     

Association between quantitative bacterial culture of bronchoalveolar lavage fluid and antibiotic requirement in dogs with lower respiratory tract signs

BackgroundHistorically, positive bacterial cultures from the lower respiratory tract (LRT) have been considered clinically relevant when quantitative bacterial cultures of bronchoalveolar lavage fluid (BALF) were >1700 colony forming units (cfu)/mL. However, this threshold might not accurately predict a requirement for antibiotics.ObjectivesTo study whether quantitative BALF bacterial culture results were predictive of antibiotic requirement in dogs with LRT signs.AnimalsThirty‐three client‐owned dogs.MethodsCross‐sectional study. Dogs with positive quantitative bacterial culture of BALF were included. Dogs were divided into 2 groups, depending on whether they had a LRT infection requiring antibiotics (LRTI‐RA) or LRT disease not requiring antibiotics (LRTD‐NRA), based on thoracic imaging features, presence of intracellular bacteria on BALF cytology, and response to treatment. Predictive effect of cfu/mL and BALF total nucleated cell count (TNCC) on antibiotic requirement, adjusting for ongoing or prior antibiotic therapy and age, were studied using logistic regression.ResultsTwenty‐two and 11 dogs were included in the LRTI‐RA and LRTD‐NRA groups, respectively. The cfu/mL was not significantly predictive of antibiotic requirement, independent of ongoing or prior antibiotic treatment and age (LRTI‐RA: median, 10 000 cfu/mL; range, 10‐3 × 10⁸; LRTD‐NRA: median, 10  000 cfu/mL; range, 250‐1.3 × 10⁹; P = .27). The TNCC was not significantly predictive of antibiotic requirement when only dogs with bronchial disease were considered (LRTI‐RA: median, 470 cells/μL; range, 240‐2260; LRTD‐NRA: median, 455 cells/μL; range, 80‐4990; P = .57).Conclusion and Clinical ImportanceThe cfu/mL is an inappropriate measure for determining whether antibiotics are of benefit in dogs with LRT signs.     

Catheter drainage of pleural fluid collections and pneumothorax

A technique for virtually atraumatic placement of small size chest catheters for suction drainage of pleural effusions and pneumothorax in the dog and cat is described. Thirty-nine dogs and two cats were treated for pyothorax (10 cases), hydrothorax (eight). chylothorax (three), haemothorax (three), haemothorax/pneumothorax (three) and pneumothorax (14). In all 41 cases, thin or viscous fluid and/or air were efficiently drained. The mean period of drainage was four days (range, 0.5 to 18 days). The average amount of fluid removed from each patient in 24 hours was 530 ml in pyothorax cases (range, 140 to 1100 ml) and 1300 ml in the other cases (range, 20 to 5000 ml). In 40 cases there were no complications related to the procedure. One dog with severe pleural adhesions was euthanased because of lung perforation and pneumothorax secondary to misplacement of the catheter.     

Bacteria associated with pyothorax of dogs and cats: 98 cases (1989-1998)

OBJECTIVE: To determine the organisms most commonly isolated from pleural fluid from dogs and cats with pyothorax. DESIGN: Retrospective study. ANIMALS: 51 dogs and 47 cats. PROCEDURE: Results of bacteriologic culture of pleural fluid samples obtained by means of thoracentesis were obtained from medical records. To obtain information on in vitro antimicrobial susceptibility of organisms commonly isolated from dogs and cats, records of all dogs and cats examined during 1998 were reviewed, and information was obtained on identity and in vitro antimicrobial susceptibility of aerobic organisms isolated from samples other than urine or urinary tract samples. RESULTS: Median ages of dogs and cats were 4 years. Bacteria were isolated from pleural fluid samples from 47 of 51 (92%) dogs and 45 of 47 (96%) cats. Obligate anaerobic bacteria were isolated from 28 dogs and 40 cats. A mixture of obligate anaerobic and facultative bacteria was isolated from 17 dogs and 20 cats. Samples from cats most often yielded a member of the nonenteric group (most commonly members of the genus Pasteurella), whereas those from dogs more often yielded a member of the family Enterobacteriaceae (most commonly E coli). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that antimicrobial agents chosen for the initial treatment of dogs and cats with pyothorax should be active against a mixture of obligate anaerobic and facultative bacteria.     

Pyothorax in a cat managed by intrathoracic debridement and postoperative ventilatory support

: A domestic-longhair cat presented due to lethargy, dyspnoea and hypersalivation. Radiographic examination revealed a bilateral pleural effusion, which was diagnosed as pyothorax based on cytological examination. Ultrasonographic examination revealed extensive loculations within the thoracic cavity. Exploratory sternotomy, under general anaesthesia, allowed the removal of approximately 100 ml of purulent fluid and debridement of a partially walled-off abscess and necrotic material from the pleural cavity. Postoperative positive-pressure ventilation was required due to severe respiratory depression. Intensive postoperative care, including intensive continuous monitoring, thoracostomy tube drainage and lavage of the pleural cavity and oesophagostomy tube feeding, was performed. Complete resolution of clinical signs had occurred by 15 days postoperatively. Clinical or radiographic abnormalities were not detected at a follow-up examination one year after surgery.     

Conservative management of pyothorax in an Amur tiger (Panthera tigris altaica)

Therapy for pyothorax, or pleural empyema, has not been described for large felids. This case describes the successful treatment of pyothorax in a captive, large felid. A 15-yr-old multiparous, female Amur tiger (Panthera tigris altaica) presented with nonspecific clinical signs caused by an insidious onset of pyothorax. Management of pyothorax cases in companion animals often involves thoracostomy tube placement with recurrent drainage of the pleural cavity, intensive supportive care, and monitoring. In this case, conservative management was elected because hospitalization was not a viable option. Thoracocentesis was performed to drain as much fluid from the chest cavity as possible, yielding more than 1.3 L. Corynebacterium sp. and unidentified anaerobic gram-positive cocci were cultured. Treatment included cefovecin subcutaneously, oral antibiotic therapy with clindamycin and marbofloxacin, meloxicam, and restricted exercise by minimizing access to the main exhibit. Significant improvement was noted clinically and radiographically 6 wk later, and no relapses were noted in the following weeks. An examination 11.5 mo later confirmed resolution.     

A Technique for Management of Bite Wounds of the Thoracic Wall in Small Dogs

Bite wounds of the chest wall in small dogs can extend into the thorax and can be associated with severe damage to chest wall muscles, ribs, and lungs. Two major problems associated with the management of these wounds are lack of sufficient muscle tissue for chest wall reconstruction, and difficulty draining the extensive dead space created in the chest wall. We describe a simple method to overcome these problems. The bite wound areas were surgically explored and all devitalized soft tissue was debrided. The pleural cavity was explored, intrathoracic injuries repaired, and a thoracic drainage tube was placed. Ribs in the injured area were stabilized in anatomic position by means of heavy gauge sutures passed around pairs of adjacent ribs, thus creating a scaffolding for soft tissues. Viable muscle and subcutaneous tissues were apposed as much as possible and the skin closed over the defect. Eleven small dogs were treated using this technique. All dogs had severe injuries to the thoracic wall muscles and eight dogs had multiple rib fractures. There was no evidence of chest wall instability in any of the dogs after surgery. Nine dogs survived the injury and were reevaluated 3 to 32 months after surgery. All were clinically normal. One dog developed wound infection and pyothorax, caused by insufficient debridement of injured muscle tissue, and died 10 days after surgery. A second dog died 24 hours postoperatively of undetermined causes.     

Comparison of two topical treatments of gastro-oesophageal regurgitation in dogs during general anaesthesia

ObjectiveTo determine whether suction, lavage and instillation of sodium bicarbonate, following a gastro-oesophageal regurgitation event under general anaesthesia, would alter oesophageal pH to a greater degree than when lavage was not used.Study designProspective, randomised, clinical study.AnimalsA group of 22 client-owned dogs.MethodsDogs presenting with gastro-oesophageal regurgitation (GOReg) under general anaesthesia were randomised into groups: no lavage (G1) or lavage (G2). All dogs underwent oesophageal suctioning until no further regurgitant material was retrieved. Dogs in G2 had oesophageal lavage with tap water until the suctioned water was clear. All dogs then had 4.2% sodium bicarbonate (0.6 mL kg^–1) instilled into the oesophagus. An oesophageal pH probe was placed to record pH immediately after: GOReg (T1), suctioning (T2), lavage of the oesophagus (T3; G2 only) and sodium bicarbonate instillation (T4). Categorical data were analysed using Fisher’s exact test, and continuous data were analysed using either the two-sample t-test or the Wilcoxon rank-sum test. Parametric data are reported as mean ± standard deviation and non-parametric data as median (interquartile range). A p value < 0.05 was considered significant.ResultsOesophageal pH was low in both groups immediately after GOReg [G1: 2.95 (2.20–4.18), G2: 3.29 (1.41–4.03)] but oesophageal pH was not significantly different between groups at T1, T2 and T4. Oesophageal lavage significantly increased pH but the overall change in pH following bicarbonate administration (T2–T4) was not significantly different between groups [G1: 3.16 ± 1.52, G2: 3.52 ± 1.47]. No adverse events following GOReg were recorded.Conclusions and clinical relevance:Both groups had similar and clinically important increases in oesophageal pH. Although oesophageal lavage increased pH, this did not affect the final oesophageal pH when sodium bicarbonate was instilled and therefore may be an unnecessary step.     

Ultrasound-guided percutaneous drainage for treatment of pyonephrosis in two dogs

Pyonephrosis refers to suppurative destruction of the parenchyma of the kidney with complete or nearly complete loss of renal function. In dogs, nephrectomy is still the most common treatment for pyonephrosis; however, in the present report, a method for percutaneous ultrasound-guided drainage of the renal pelvis in dogs with pyonephrosis that does not require local or general anesthesia was described, and results of the procedure in 2 dogs were reported. Briefly, dogs were positioned in lateral recumbency with the affected side up, and skin overlying the affected kidney was aseptically prepared. The dilated renal pelvis was punctured percutaneously, under ultrasound guidance, with a 22-gauge needle, and a sample of material was obtained for analysis. The needle was then replaced with an IV catheter, and as much pus as possible was removed from the renal collecting system. A povidone iodine solution was then used to lavage the renal pelvis. Ultrasound-guided drainage and lavage of the renal pelvis was repeated daily until the renal pelvis was so small that it could no longer be punctured. Both dogs recovered and were reported by the owners to be healthy after the procedure.     

Thoracic empyema in the dog; a report of twenty-two cases

The clinical findings, diagnosis and treatment of 22 cases of canine empyema are reported. Relevant presenting signs were tachypnoea or dyspnoea with pyrexia of variable duration, usually with a history of transient response to antibiotic therapy. Diagnosis was made by radiographic demonstration of free pleural fluid followed by bacterial examination of thoracic aspirates. Treatment consisted of parenteral administration of antibiotics accompanied, in most cases, by removal of the exudate either by aspiration, drainage through an indwelling cannula or thoracotomy. Sixteen dogs recovered from the initial illness. Two of these were destroyed within four months as a result of recurrence and the remaining fourteen survived in good health for follow up periods between six months and seven years after treatment.     

Open drainage, intra-articular and systemic antibiotics in the treatment of septic arthritis/tenosynovitis in horses.

Open drainage was used to treat 26 horses with persistent or severe septic arthritis/tenosynovitis. Infected synovial structures were drained through a small (3 cm) arthrotomy incision that was left open and protected by a sterile bandage. Joint lavage was performed in all 26 horses. In addition to systemic antibiotics, 23 of these horses were also treated with intra-articular antibiotics; amikacin (17 horses), gentamycin (2 horses), cefazolin (2 horses), and 2 horses were injected at different times with gentamycin and amikacin. The infection was eliminated from the involved synovial structures in 25 of 26 horses; 24 survived and were released from the hospital. The arthrotomy incisions healed by granulation in 16 horses; in 9 horses the arthrotomy incision was sutured closed once the infection was eliminated. Seventeen horses returned to soundness and resumed athletic function. Open drainage was an effective method of achieving chronic drainage from a joint or tendon sheath. It is indicated in horses that have established intra-synovial infections or in horses that do not respond to joint lavage through needles.     

Successful treatment of pulmonary aspergillosis in a cat

A 7-year-old, spayed female Domestic Longhair cat was evaluated for a 6-week history of coughing. Thoracic radiography revealed a pleural effusion. Thoracic ultrasound revealed a pleural effusion and a focal lung mass. The cat underwent exploratory thoracotomy and a total left pneumonectomy was performed. Histopathology and cultures revealed fungal pneumonia and pyothorax caused by Aspergillus fumigatus. Abdominal ultrasound, repeat thoracic radiography, urinalysis with culture, and retroviral screening failed to detect evidence of systemic disease. The cat's poorly regulated diabetes mellitus is suspected to be the predisposing factor allowing a fungal pulmonary infection to become established. At 18 months after surgery the cat was still disease-free. To our knowledge this is the first reported case of successful treatment of pulmonary aspergillosis in the cat.     

Biliothorax in a Siamese cat

A 2-year-old male neutered cat presented for further investigation of biliothorax. The cat was initially treated for pyothorax, including bilateral chest drains for lavage of the pleural space. Five days later, the pleural effusion turned clear-yellow and had a bilirubin concentration of 427 μmol/l compared to the serum bilirubin concentration of 15 μmol/l. Exploratory surgery revealed a 2mm tear in the diaphragm, with a corresponding 2mm defect in the diaphragmatic surface of the gall bladder, creating a fistula between the gall bladder and the pleural cavity. The defects were repaired routinely and the cat made a full recovery. It was suspected that the tears had been created at the time of the thoracostomy tube placement. Biliothorax has not been described before in a cat, and appears to be a rare complication following thoracostomy tube placement.