DIAGNOSTIC PNEUMOPERICARDIOGRAPHY IN DOGS WITH SPONTANEOUS PERICARDIAL EFFUSION

To evaluate the diagnostic accuracy of pneumopericardiography, diagnostic pneumopericardiograms from 39 dogs with spontaneous pericardial effusion of various etiologies were reviewed. Diagnoses were confirmed by surgical biopsy, necropsy, or follow-up evaluation. Thirty-two of 39 studies (82%) were considered diagnostic. There were one false-positive and six false-negative studies. Fifteen of 16 studies (94%) in dogs with idiopathic sanguinous pericardial effusion were negative (i.e., similar to those in normal dogs). Seven of 12 right atrial hemangiosarcomas (58%), six of six heartbase neoplasms (100%), and two of two pericardial cysts (100%) were outlined. Studies in two cases of infective pericarditis revealed abnormal findings, while a negative study was obtained in one patient with pericardial mesothelioma. Lateral positions were most valuable in idiopathic effusions and for outlining heartbase neoplasms. The left lateral recumbent position was particularly important for outlining hemangiosarcomas. Pericardial cysts were profiled best in ventral or dorsal recumbent positions. This study documents the high diagnostic potential of technically adequate pneumopericardiograms in the etiologic diagnosis of pericardial effusion in the dog.     

Idiopathic pericardial haemorrhage in dogs: a review of fourteen cases

The clinical and radiological findings in 14 cases of idiopathic pericardial haemorrhage are reported. Seven dogs recovered following treatment by pericardial drainage (six cases) or pericardectomy (one case). Four cases later relapsed of which two were again treated successfully. One dog apparently responded to conservative treatment but died of a relapse one month later. In the remaining six animals, which all died or were destroyed during either investigation or treatment, pericardial haemorrhage was confirmed at post-mortem examination.     

Pericardial effusion and cardiac tamponade in a cat with extranodal lymphoma

A five-year-old domestic longhaired cat was evaluated for a seven-day history of worsening respiratory distress. Serum analysis for feline leukaemia virus antigen was positive. Pleural effusion was detected on thoracic radiographs and echocardiography revealed a pericardial effusion and cardiac tamponade. Cytological evaluation of the pleural and pericardial effusions showed lymphoblastic cells indicative of disseminated lymphoma. Following thoracocentesis and pericardiocentesis, the cat was treated for lymphoma using the University of Wisconsin-Madison chemotherapy protocol. The cat was sent home after three days and, at the time of writing (six months after initial presentation), was still symptom free. To the authors' knowledge, this is the first report confirming pericardial effusion and cardiac tamponade in the cat as a direct result of an extranodal lymphoma with cytological evidence of neoplastic cells in the pericardial fluid.     

Idiopathic effusive pericarditis with tamponade in the horse

Pericarditis and pericardial effusion are considered to occur rarely in the horse. The clinical and laboratory features of idiopathic pericarditis with effusion diagnosed in 10 horses over a seven-year period were reviewed. Consistent physical findings included tachycardia, ventral oedema, jugular venous distention and diminished heart sounds. Electrocardiographic features included diminished voltages and electrical alternans, and the effusion was identified by echocardiography in the six horses in which it was performed. Pericardiocentesis relieved clinical signs in nine horses. Laboratory analysis of pericardial fluid samples classified six cases as aseptic serofibrinous, three cases as eosinophilic, and one case as histiocytic. One horse died and three were destroyed. The remaining six horses recovered following pericardiocentesis (performed once or twice) with or without corticosteroid treatment, and were alive one month to seven years after diagnosis.     

Malignant mesothelioma in urban dogs

Clinical and postmortem materials from six dogs with a diagnosis of malignant mesothelioma were studied retrospectively. The dogs were urban pets with clinical signs of malignant effusions. Two mesotheliomas were pleural, one pericardial, and one peritoneal. Both pleura and pericardium were involved in one dog, and the pleura and peritoneum in another. On gross examination at necropsy, diffuse granular or velvety plaques covering mesothelial surfaces were found in all dogs; firm discrete pleural nodules also were present in two dogs. Neither distant metastases nor areas of deep lung invasion were found. The tumors varied histologically, but the most common type was epithelial with a papillary pattern. Ultrastructurally, the neoplastic cells had prominent surface microvilli, numerous desmosomes, and tonofilaments. Lung tissue from these dogs and from control dogs was evaluated for the presence of ferruginous bodies. Asbestos bodies were found in three of five dogs with mesotheliomas but rarely were found in control dogs. As a group, the mesothelioma cases had significantly more asbestos bodies and total ferruginous bodies than controls. The clinical and morphologic appearance of canine mesothelioma is similar to human mesothelioma and also may be associated with exposure to airborne fibers.     

Evaluation of once daily treatment with cyclosporine for anal furunculosis in dogs

Twenty-four dogs with anal furunculosis were treated with cyclosporine once daily for 13 weeks at dosages of 1.5, 3.0, 5.0 or 7.5 mg/kg, and re-examined after six and 12 months. After 13 weeks the disease in six of the dogs was in remission, 11 were controlled or improved and seven had failed to respond. The response of the dogs given the highest dose was significantly better than the response of the other groups taken together (P < 0.014), and better than the responses of the groups given 1.5 mg/kg and 5 mg/kg (P < 0.05). The dogs improved clinically during the treatment, most rapidly during the first five weeks. Of the six dogs that were in remission after 13 weeks, three relapsed after one, two and six months. The 11 dogs that were improved or controlled after 13 weeks were either left untreated or were continued on cyclosporine medication for one to three months at a dosage of 1.5 to 7.5 mg/kg; the disease went into remission in four cases and remained controlled in the other seven, but four of the 11 cases relapsed during the 12 months following the treatment. The side effects observed included increased coat turnover and transient vomiting.     

Flow cytometric analysis of effusions in dogs and cats with the automated haematology analyser ADVIA 120

Samples were aspirated from 12 thoracic effusions, 10 abdominal effusions and four pericardial effusions in 17 dogs and nine cats. They were analysed cytometrically with the ADVIA 120 flow cytometer and the results were compared with the results of cytological examinations of May-Grünwald-Giemsa-stained smears. The conventional cytology revealed a purulent or pyogranulomatous inflammation in 12 of the animals, lymphoma in six, malignant histiocytosis in two, and an unspecified carcinoma in two; two animals had a chylous effusion, two had a modified transudate, and one dog had an idiopathic pericardial haemorrhage. The flow cytometric analysis was based on cellular volume, peroxidase staining intensity and the determination of nuclear lobularity, and made it possible to identify predominant cell lineages and cell debris, which were shown in characteristic cytograms. Inflammatory effusions, monocytic proliferation and lymphoma were easily detected, but carcinoma cells and mesothelial cells were classified as 'mononuclear blasts'.     

Radial carpal bone fractures in 15 dogs

Between 1977 and 1992, 15 adult dogs were presented to the Universities of Bristol, Glasgow, Liverpool and London with fractures of the radial carpal bone which had occurred without a known episode of violent trauma. Eleven of the dogs were boxers and the other breeds affected were a Pharaoh hound, rottweiler, springer spaniel and a greyhound. The condition was bilateral in three cases. Eleven dogs were treated surgically by cast immobilisation (four cases), fragment removal (one case), lag screw fixation (three cases), pan-carpal arthrodesis (one case) and lag screw reduction followed by pan-carpal arthrodesis (two cases). The remaining four dogs were treated conservatively with rest and tactical use of non-steroidal anti-inflammatory drugs. Follow-up periods ranged from two months to 11 years. Varying degrees of lameness, which tended to be exacerbated by exercise, persisted in all cases. The radial carpal bone appears to have at least three separate centres of ossification which eventually fuse; their planes of fusion correspond approximately to the two main fracture lines. These areas of fusion could be weak points within the radial carpal bone.     

Cardiac troponins I and T in dogs with pericardial effusion

Cardiac troponin I (cTnI) and cardiac troponin T (cTnT) are sensitive and specific markers for myocardial ischemia and necrosis. Dogs with pericardial effusion frequently have myocardial ischemia and necrosis, and these changes are more severe in dogs with hemangiosarcoma (HSA). We investigated the utility of using serum cTnI and cTnT concentrations to identify the idiopathic pericardial effusion from that associated with HSA. Blood samples for measurement of cTnI and cTnT concentrations were collected before pericardiocentesis in 37 dogs with pericardial effusion. Eighteen dogs had a mass consistent with HSA, 6 dogs had idiopathic pericardial effusion, 1 dog had mesothelioma, and 1 dog had a heart base tumor. No final diagnosis was achieved for 11 dogs. Dogs with pericardial effusion had significantly higher serum concentrations of cTnI (P < .001) but not cTnT (P = .16) than did normal dogs. Dogs with HSA had significantly higher concentrations of cTnI (2.77 ng/dL; range: 0.09-47.18 ng/dL) than did dogs with idiopathic pericardial effusion (0.05 ng/dL; range: 0.03-0.09 ng/dL) (P < .001). There was no difference in the concentration of cTnT between dogs with HSA and those with idiopathic pericardial effusion (P = .08). Measurement of cTnI may be useful in helping to distinguish between idiopathic pericardial effusion and pericardial effusion caused by HSA.     

Echocardiographic evaluation of cardiac tamponade in dogs before and after pericardiocentesis: four cases (1984-1986)

The echocardiographic (M-mode and 2-dimensional) features (before and after pericardiocentesis) of 4 dogs with pericardial effusion and clinical evidence of cardiac tamponade were reviewed. M-Mode echocardiography revealed pericardial effusion, with exaggerated swinging motion of the heart and abnormal septal motion in all 4 dogs. In each case, 2-dimensional echocardiography demonstrated right ventricular diastolic free-wall collapse. Three dogs had right atrial diastolic collapse as well. Clinical signs improved, and right ventricular and right atrial diastolic collapse subsided after pericardiocentesis. Two-dimensional echocardiographic features of right atrial and ventricular collapse were used as indicators for determining the presence of cardiac tamponade.     

Adverse events associated with pericardiocentesis in dogs: 85 cases (1999–2006)

Objective – To quantify the frequency of adverse events occurring during or post pericardiocentesis and to determine if adverse events are related to the cause of the pericardial effusion or frequency of pericardiocentesis.
Design – Retrospective study.
Setting – Referral hospital.
Animals, Intervention and Measurements – Medical records of 85 dogs that underwent 112 episodes of pericardiocentesis were reviewed. Any adverse events during pericardiocentesis and in the 48 hours post pericardiocentesis were noted. The frequency of adverse events was compared between dogs with a suspected neoplastic cause and a suspected nonneoplastic cause of their pericardial effusion and also between the first and subsequent pericardiocenteses.
Main Results – The incidence of adverse events was 10.7% within 1 hour of pericardiocentesis and 15.2% within 48 hours. There was no significant difference in the frequency of adverse events between the groups. Most adverse events identified were dysrhythmias. Forty-one percent of those dogs with adverse events were euthanized or died within 48 hours.
Conclusion – The incidence of adverse events seen within 48 hours of pericardiocentesis was 15.2%.     

Efficacy, safety and palatability of a new broad-spectrum anthelmintic formulation in dogs

The efficacy, safety and palatability of a new flavoured chewable anthelmintic tablet were investigated in dogs. The efficacy, based on worm counts, of a single recommended therapeutic dose (RTD) of 5 mg pyrantel + 20 mg oxantel + 5 mg praziquantel/kg bodyweight was assessed in experimental infections (EI) and natural infections (NI) with Trichuris vulpis, Echinococcus granulosus and Toxocara canis. For T vulpis, the efficacy of the treatment was 99.3 per cent in EI (comparing groups of six treated and six control dogs) and 100 per cent in NI (nine treated and nine control dogs). For E granulosus, the efficacy was more than 99.9 per cent in EI (11 treated and 11 control dogs). For T canis, the efficacy was 94.3 per cent in EI (10 treated and 10 control dogs) and 100 per cent in NI (12 treated and 13 control dogs). In a field study, Ancylostoma caninum (11 dogs) and T canis (11 dogs) faecal egg counts were reduced by more than 99 per cent, and in eight dogs with Dipylidium caninum proglotides in the faeces the efficacy was 100 per cent. The tablets were readily consumed by 56 of 64 (87.5 per cent) privately owned dogs. Safety was assessed in groups of six dogs treated either once with twice the RTD, once with six times the RTD, with twice the RTD on three consecutive days, or untreated. There were no significant differences in blood parameters between the groups, and no abnormal clinical findings. Two dogs treated with six times the RTD vomited, but no vomiting was observed when administration was repeated two days later.     

Evaluation of the presence of selected viral and bacterial nucleic acids in pericardial samples from dogs with or without idiopathic pericardial effusion

Many viruses have been identified in pericardial fluid and in tissue samples from humans with pericarditis by means of molecular diagnostics. In canine idiopathic pericardial effusion there is as yet no conclusive evidence to support the involvement of an infectious agent. This study was designed to investigate a possible relationship between idiopathic pericardial effusion in dogs and viruses most commonly encountered in humans affected with viral pericarditis. Coxsackievirus B3 RNA, influenza virus type A RNA, human adenovirus type 2 DNA, human cytomegalovirus DNA, and parvovirus B19 DNA were investigated using PCR on pericardial effusion samples and pericardial tissue specimens collected from 14 dogs with idiopathic pericardial effusion. PCR was also used to test for two bacteria, Borrelia burgdorferi and Chlamydia pneumoniae. The same microorganisms were also looked for in pericardial effusions or pericardial washes from 10 dogs with neoplastic pericardial effusion, and in samples collected from 10 dogs which died of a non-cardiac disease. One pericardial effusion sample from a dog with the idiopathic form of the disease tested positive for influenza virus type A and sequencing of the amplicon confirmed the PCR result. In another dog from the same group a cytomegalovirus was detected by PCR in the effusion, but sequencing showed this to be a false-positive result. The genomes of the microorganisms investigated were not detected in neoplastic effusions or pericardial washes. The results indicate that viral and bacterial DNA/RNA of relevance for human pericarditis is rare in pericardial samples from dogs with idiopathic pericardial effusion. The finding of influenza type A viral RNA in pericardial fluid from one dog with the idiopathic form of the disease warrants further investigation.     

Azathioprine therapy for acquired myasthenia gravis in five dogs.

Five dogs with acquired myasthenia gravis (MG), verified via positive serum acetylcholine (ACh) receptor antibody concentrations, were treated with a drug protocol including azathioprine (AZA). Four of the five dogs were concurrently treated with pyridostigmine. Azathioprine was used as the sole immunosuppressive agent in four dogs. One dog was temporarily treated with a combination of an immunosuppressive dose of prednisone and AZA, then maintained on AZA as the sole immunosuppressive drug. Three patients experienced complete remission of clinical signs within three months of therapy. In the four dogs for which follow-up serum ACh receptor antibody concentrations were available, initial versus final concentrations decreased substantially (81%), coincident with clinical improvement. One dog died suddenly due to a suspected myasthenic crisis before attaining the target dose of AZA. Two of the four surviving dogs were euthanized approximately one and seven years after diagnosis. One of these two dogs was euthanized because of a rib osteosarcoma, and the other dog was euthanized because of paraparesis of undetermined cause. The remaining two dogs were alive and doing well at the time of final follow-up evaluation, approximately six months and one year after diagnosis. The use of AZA as a therapeutic agent for acquired canine MG has not been investigated. The cases presented in this report suggest a potentially important role for AZA in the treatment of acquired MG in dogs.     

Chronic dermatophytosis due to Microsporum persicolor infection in three dogs

Microsporum persicolor, a rare zoophilic dermatophyte, was isolated from three dogs with skin disease of between three and five years duration. Skin lesions consisted of scaling with minimal alopecia or erythema. Severe inflammatory changes were not observed clinically and pruritus was absent or mild. The face was affected in all three cases and more widespread lesions were found in two. The diagnosis of dermatophytosis was confirmed in each case by the demonstration of fungal hyphae in the epidermal stratum corneum on examination of skin biopsies. However, hair shaft invasion was not observed in either skin scrapings or histological sections. Of the three dogs, one partially improved following repeated courses of treatment, a second completely recovered with 11 weeks of combined topical and systemic therapy. Response to therapy could not be assessed in the remaining case.     

Studies on the association of Aspergillus fumigatus with ocular infections in animals

The occurrence and aetiological significance of Aspergillus fumigatus, an opportunistic pathogen, have been studied in 93 animals with various ophthalmological problems. A total of 93 eye swabs collected from 35 mules, 26 dogs, 13 fowl, 11 cattle, five buffaloes and three camels were investigated mycologically for the presence of A fumigatus. The pathogen was isolated in pure and heavy growth from the swabs from two dogs, one bull, one mule and one fowl. The fungus was also demonstrated directly in clinical material by the potassium hydroxide technique. A fumigatus could not be cultured from the buffaloes and camels. All the five cases had been treated with broad spectrum antibiotics and cortisone and two had received traumatic injury to the eyes (one mule and a bull). The organism was not isolated in pure culture from the conjunctival swabs of 22 apparently healthy animals (11 dogs, six mules, three fowl and two cattle). Many other saprophytic fungi were recovered in mixed cultures but were considered to be contaminants. The clinical signs and diagnostic criteria of oculomycosis have been discussed.     

Biochemical analysis of pericardial fluid and whole blood in dogs with pericardial effusion

Studies evaluating pericardial fluid analysis in dogs to determine the etiology of pericardial effusions have yielded conflicting results. The purpose of this prospective study was to compare acid-base status, electrolyte concentrations, glucose, and lactate of pericardial fluid to peripheral blood from dogs with pericardial effusion and to compare these variables between dogs with neoplastic and nonneoplastic pericardial effusion. Acid-base status, electrolyte concentrations, glucose, hematocrit, urea nitrogen, and lactate concentrations were evaluated in peripheral blood samples and in pericardial effusion samples of 41 client-owned dogs with pericardial effusion. Common abnormal findings in the peripheral blood of dogs with pericardial effusion included hyperlactatemia (n = 38 [of 41]; 93%), hyponatremia (n = 25/41; 61%), hyperglycemia (n = 13/41; 32%), and hypermagnesemia (n = 13/41; 32%). Bicarbonate, sodium, ionized calcium, glucose, and hematocrit were all significantly lower in the pericardial fluid compared with peripheral blood, whereas lactate, chloride, and PCO2 were significantly higher in the pericardial fluid. When comparing the concentrations of variables in the pericardial fluid of dogs with neoplasia (n = 28) to those without neoplasia (n = 13), pH, bicarbonate, and chloride were significantly lower in dogs with neoplasia, whereas lactate, hematocrit, and urea nitrogen were significantly higher in the pericardial fluid of dogs with neoplasia. The difference between peripheral and pericardial glucose concentrations was significantly larger in dogs with neoplasia than in dogs without neoplasia. Although differences between variables in dogs with neoplastic and nonneoplastic pericardial effusion were documented, clinical relevance is likely limited by the degree of overlap between the 2 groups.     

Hypothyroidism in the dog: a retrospective study of sixteen cases

Sixteen dogs with confirmed hypothyroidism were reviewed. The diagnosis was based on subnormal plasma thyroxine concentration and poor response following TSH administration. Common clinical signs were alopecia (12 dogs), lethargy (11) and obesity (11). Plasma cholesterol concentrations were abnormally high in 10 of 14 cases tested, five of 12 were anaemic and three of five had increased creatine phosphokinase activity. Skin changes compatible with endocrinopathy were present in all five cases biopsied. Spontaneous muscle activity was found on electromyography in four cases so examined. All dogs were treated with sodium levothyroxine, and 10 of 13 for which information was available responded satisfactorily.     

Temporomandibular joint ankylosis in cats and dogs. A report of 10 cases.

Temporomandibular joint (TMJ) ankylosis is characterized by difficulty or inability to open the mouth. The ankylosis may be articular ('true') or extra-articular ('false'). Clinical signs, radiographic studies, treatment and follow-up are presented in a retrospective study involving five cats and five dogs. The findings were compared with TMJ ankylosis in humans. CT imaging with three-dimensional reconstruction proved to be of great value in determining the extent of the abnormalities and helped with preoperative planning. Articular TMJ ankylosis occurred in six animals and extra-articular TMJ ankylosis was found in the other four cases. In three cats and in three dogs, the TMJ ankylosis was trauma related; the remaining patients were diagnosed with a tumour. Resection of ankylosing tissue in false ankylosis or gap arthroplasty in true ankylosis was successful in all of the trauma induced cases. In the two cats, with tumour related ankylosis, the ankylosis was caused by an osteoma and resection had a good prognosis, whereas the two dogs had to be euthanatized.     

Therapeutic pericardiocentesis in the dog and cat

Pericardial effusion is a potentially life-threatening problem leading to a rise in the intrapericardial pressure resulting in varying degrees of hemodynamic compromise. Cardiac tamponade occurs when the intrapericardial pressure equals or exceeds right ventricular diastolic filling pressures leading to a decreased cardiac output. In dogs, the most common causes of pericardial effusion that require pericardiocentesis are cardiac neoplasia and idiopathic pericardial effusion (IPE). The incidence of cardiac neoplasia in dogs is low, and it is rare in cats. In dogs, hemangiosarcoma and chemodectoma are the two most common types of cardiac neoplasia. In cats, lymphosarcoma is the most common form of cardiac neoplasia, but they are more likely to develop pericardial effusion secondary to congestive heart failure or feline infectious peritonitis. Common histories include lethargy, dyspnea, anorexia, collapse, and abdominal distension. Pericardiocentesis is used to stabilize animals with life-threatening cardiac tamponade, relieve the pressure leading to right-sided heart failure, and obtain fluid samples for diagnostic evaluation. The fluid should be quantified and characterized. Serious complications associated with pericardiocentesis are rare. Complications include cardiac puncture, arrhythmias, and laceration of a tumor or coronary artery resulting in intrapericardial hemorrhage or sudden death.