Dermatosis and associated systemic signs in a cat with thymoma and recently treated with an imidacloprid preparation

A cat was presented with acute-onset exfoliative erythroderma and gross and histopathological lesions of erythema multiforme. Marked cardiovascular abnormalities including heart failure occurred concurrently and a dermatogenic enteropathy was also seen. Medical treatment resolved the dermatopathy and enteropathy but the heart failure progressed. A drug reaction was initially suspected to be the underlying cause with no neoplasia being detected, but repeat radiographs subsequently revealed a thymoma which had not been visible on the initial radiographs. The dermatopathy may have been a paraneoplastic disease associated with thymoma and, possibly, exacerbated by a drug reaction to imidacloprid. The cardiovascular and gastroenterological diseases were thought to be systemic effects associated with the exfoliative erythroderma. The thymoma was surgically removed but the cat subsequently died from heart failure.     

Idiopathic pleural effusion and pulmonary thromboembolism in a dog with autoimmune hemolytic anemia

Pleural effusion and pulmonary thromboembolism were diagnosed in a dog with autoimmune hemolytic anemia. Clinical signs of tachypnea, then dyspnea in association with pleural effusion, developed after 10 days of immunosuppressive corticosteroid therapy (greater than 2 mg/kg of body weight/d, PO). The diagnosis of pulmonary thromboembolism was made tentatively on the basis of results of a radionuclide lung perfusion scan and was confirmed by exploratory thoracotomy and lung biopsy. Tachypnea and pleural effusion gradually resolved without specific treatment, and additional episodes of anemia or dyspnea have not been observed. The pathogenesis of these findings was suspected to be related to corticosteroid-induced thrombotic tendencies, persistent thrombocytosis (greater than 800,000 cells/microliters), and vascular injury caused by repeated jugular venous catheterization. Pulmonary thromboembolism should be considered in dogs that develop clinical signs of tachypnea and/or pleural effusion during administration of immunosuppressive dosages of corticosteroids.     

COMPARISON BETWEEN THORACIC RADIOGRAPHIC FINDINGS AND POSTMORTEM DIAGNOSIS OF THORACIC DISEASES IN DYSPNEIC COMPANION RATS (RATTUS NORVEGICUS)

Companion rats are often presented to veterinarians for respiratory difficulties. Dyspnea in rats is most commonly due to infectious pneumonia, and thoracic neoplasia can go undiagnosed ante mortem due to a mistaken interpretation of pneumonia. In domestic carnivores, pulmonary nodular patterns have been shown to correlate with lung neoplastic diseases and infectious diseases. The main objective of this retrospective case series study was to determine whether certain radiographic criteria could be correlated with the presence of thoracic infectious disease and neoplastic disease in companion rats. A secondary objective was to determine whether the patient's sex and age were different between rats diagnosed with infectious versus neoplastic disease. Medical records and thoracic radiographs of dyspneic companion rats presented to the University of California at Davis, William R. Pritchard Veterinary Medical Teaching Hospital during the time period from January 2000 to December 2014 were reviewed. Rats with postmortem confirmation of thoracic lesions were included in the study. Thoracic radiographs were evaluated for positioning, lesion distribution, lung lobe involved, pulmonary pattern, mediastinal and pleural lesions by three observers blinded to diagnosis. Thirty rats were included in the study, including 23 rats with an infectious disease and seven with neoplasia. Mediastinal lesions were significantly more prevalent in the group diagnosed with thoracic neoplasia (P = 0.031), in particular cranially (P = 0.048). Although there was an overlap between the two groups, findings indicated that the presence of cranial mediastinal lesions may be helpful for differentiating neoplastic from infectious disease in rats.     

Pulmonary thromboembolism in dogs: 47 cases (1986-1987)

Medical records of 47 dogs with pulmonary thromboembolism were reviewed. Middle-aged to older dogs predominated and dyspnea and arterial hypoxemia were consistent clinical findings. Thoracic radiographic findings were variable. Cardiac disease, neoplasia, hyperadrenocorticism, disseminated intravascular coagulation, and sepsis were identified most frequently. Multiple disease processes were identified in 64% of the dogs.     

Reversible pulmonary hypertension in a cat

A 13-year-old, neutered female domestic shorthair cat was presented for sudden respiratory distress following palliative radiotherapy and the combined administration of a single dose of carboplatin for the treatment of recurrent fibrosarcoma. Clinical and radiographic findings were suggestive of pleural effusion. Echocardiography revealed marked right-sided cardiac enlargement associated with tricuspid regurgitation and Doppler evidence of pulmonary hypertension. After 25 days of treatment for congestive heart failure and suspected pulmonary thromboembolism, clinical signs and echocardiographic and Doppler evidence of right-sided cardiac enlargement and pulmonary hypertension had completely resolved. To the best of the authors' knowledge, this is the first report of reversible pulmonary hypertension, likely secondary to pulmonary thromboembolism, in a cat.     

Clinicopathological investigation of primary, uncomplicated maedi-visna virus infection.

Maedi-visna virus infection in a flock of sheep in Scotland was associated with respiratory disease, neurological disease, mastitis and lameness. The major clinical signs were dyspnoea (particularly on exercise), progressive fore- and hindlimb ataxia and balance defects, mammary induration and multilimb lameness, occasionally with enlarged carpal joints. Pathological examinations revealed lesions in the lungs, central nervous system, mammary glands and joints which were consistent with those induced by maedi-visna virus. The was no clinical or pathological evidence of concurrent sheep pulmonary adenomatosis, and pulmonary bacterial infections, when they occurred, were superimposed on the lesions due to maedi-visna virus.     

Evaluation of thoracic radiographs as a screening test for dogs and cats admitted to a tertiary‐care veterinary hospital for noncardiopulmonary disease

Thoracic radiographs are used as a screening tool for dogs and cats with a variety of disorders that have no clinical signs associated with thoracic structures. However, this practice has never been supported by an evidence‐based study. The objective of this retrospective observational study was to determine if certain canine and feline populations have a higher proportion of radiographic abnormalities, and whether any of these abnormalities are associated with patient hospitalization and outcome. Patients were excluded if current or previous examinations revealed evidence of primary respiratory or cardiac disease, malignant neoplasia, or an abnormal breathing pattern consistent with pulmonary pathology. Any notable thoracic change in the radiology report was considered important and evaluated in this study. One hundred and sixty‐six of these included patients were dogs and 65 were cats. Of the 166 dog radiographs evaluated, 120 (72.3%) had normal thoracic radiographs, while 46 (27.7%) had radiographic abnormalities. Of the sixty‐five cats included, 36 (55.4%) had normal radiographs, while 29 (44.6%) had abnormal radiographs. Canine patients with abnormal radiographs had a significantly higher lactate level (P‐value 0.0348) and feline patients with abnormal radiographs had a significantly lower packed cell volume (P‐value 0.012). A large proportion of patients that had screening thoracic radiographs (32.5%) had documented abnormalities, but a relatively low percentage (6.5%) of our total population had their clinical plan changed as a consequence of detection of these abnormalities. Findings indicated that abnormal screening thoracic radiographs are more likely in dogs with an elevated lactate and cats with anemia, or a low normal hematocrit.     

Spinal spondylosis and acute intervertebral disc prolapse in a European brown bear (Ursus arctos arctos)

A 22-year-old male European brown bear (Ursus arctos arctos) was presented to the Onderstepoort Veterinary Academic Hospital after an acute onset of hind limb paralysis 4 days earlier. Previous radiographs revealed marked degenerative joint disease of the stifles, tarsi and digits. The clinical findings were consistent with acute disc prolapse. Lateral radiographs of the entire vertebral column were made as well as ventrodorsal pelvic radiographs. The latter were within normal limits. The vertebral column revealed multiple lesions consistent with chronic and acute disc herniations. Lateral compression of the caudal lumbar nerve roots could not be ruled out. Owing to multiple significant findings of the vertebral column and the poor prognosis for full recovery after surgery, the bear was euthanased. The diagnosis of an acute disc prolapse and multiple chronic disc herniations was confirmed on necropsy.     

RETROSPECTIVE ASSESSMENT OF COMPUTED TOMOGRAPHIC IMAGING OF FELINE SINONASAL DISEASE IN 62 CATS

Sixty-two cats with sinonasal disease were evaluated with computed tomography. Findings that may lead to a computed tomographic diagnosis of nasal neoplasia versus rhinitis included osteolysis of the paranasal bones, moderate to severe turbinate destruction, lysis of the nasal septum, the presence of a homogenous space occupying mass, and extension of the disease process into the orbit or facial soft tissues. These findings were not pathognomonic for neoplasia and may be associated with severe rhinitis; therefore, nasal biopsy was recommended. When compared with parallel radiographic studies, computed tomography was not more sensitive than radiographs at detecting the presence of nasal cavity abnormalities in cats with referable clinical signs but was more sensitive at localizing these changes and determining the extent of disease.     

Diagnosis of erythema multiforme associated with thymoma in a dog and treated with thymectomy

A 7 yr old Labrador retriever initially presented for severe halitosis, mild ptylism, and depigmentation of the nasal planum. Erythema multiforme was diagnosed based on clinical signs and dermatopathology. Treatment was initiated but the condition did not resolve. Six months later, the dog was diagnosed with a mediastinal mass. Trucut biopsy was performed and histopathologic diagnosis was consistent with a thymoma. A median sternotomy was performed, the thymoma was excised, and the dog recovered well. Four months postoperatively, there were no longer any obvious erythema multiforme lesions and the skin condition was controlled without medication. Erythema multiforme may be a paraneoplastic disorder associated with thymoma in the dog, similar to thymoma-associated exfoliative dermatitis in the cat. Clinical signs of erythema multiforme may warrant performing thoracic radiographs or thoracic CT to rule out thymoma as an underlying cause.     

IMAGING DIAGNOSIS—HYPOGLYCEMIA ASSOCIATED WITH CHOLANGIOCARCINOMA AND PERITONEAL CARCINOMATOSIS IN A HORSE

An 8‐year‐old Thoroughbred mare presented for decreased appetite, ataxia, and weakness. Abdominal ultrasound revealed a large volume of anechoic fluid along with multiple masses involving the spleen, liver, and diaphragm. Pleural fluid was identified via ultrasonography and thoracic radiography. Thoracic radiographs also identified pulmonary interstitial nodules, an undulant dorsal diaphragmatic margin and enlargement of tracheobronchial lymph nodes. Clinical signs of weakness and mild seizures were concurrent with hypoglycemic episodes. The final diagnosis was cholangiocarcinoma with extensive metastasis. Clinical signs of weakness, ataxia, and seizures were attributed to a paraneoplastic syndrome of tumor‐associated hypoglycemia that has been infrequently reported in horses.     

Clinical course, diagnostic findings and necropsy diagnosis in dyspneic cats with primary pulmonary parenchymal disease: 15 cats (1996–2002)

Objective: Correlate the necropsy diagnosis with the history, diagnostic findings, and clinical course of dyspneic cats with primary lung parenchymal disease. Design: Retrospective study. Setting: Matthew J. Ryan Veterinary Hospital of the University of Pennsylvania. Animals: Client‐owned cats over 6 months of age hospitalized in the Intensive Care Unit (ICU) with a primary problem of respiratory distress that had pulmonary parenchymal disease on thoracic radiographs, and a complete necropsy. Interventions: None. Measurements and main results: Cats included were assigned into 2 groups based on the pulmonary histopathology: inflammatory (n=8) and neoplastic (n=7) disease. No statistical difference was found between the groups with regard to age, body weight, clinical signs, duration of clinical signs, physical examination findings, thoracic radiography, duration of hospitalization, treatment, and outcome. Cats with neoplasia had a statistically higher mean total white blood cell count (26.60 k/μL±10.41) than those with inflammatory lung disease (11.59 k/μL±4.49; P=0.026). Cats with bacterial or viral pulmonary disease had a significantly shorter median duration of illness (5 days, range 1–7 days) than all other cats (30 days, range 7–365 days; P=0.0042). Ultrasound guided pulmonary fine‐needle aspiration (FNA) provided an accurate diagnosis in 5/5 cases. Conclusions: Forty‐seven percent of cats with pulmonary parenchymal disease had neoplasia. The clinical diagnosis was difficult to obtain ante‐mortem; lung FNA appeared to be the most helpful diagnostic tool in these cases.     

RADIOGRAPHIC FINDINGS IN THE THORAX OF DOGS WITH LEPTOSPIRAL INFECTION

Thoracic radiographs of 4 dogs with confirmed and 1 dog with suspected leptospirosis were reviewed. In all dogs a reticulonodular pulmonary opacity was noted, affecting the entire lung in 3 and predominantly the caudodorsal lung field in 2 dogs. The radiographic lung pattern described is associated with pulmonary hemorrhage probably due to endothelial damage and vasculitis. Pulmonary manifestations in dogs with leptospirosis may be misinterpreted and attributed to neoplasia, pneumonia, edema, hemorrhage due to disseminated intravascular coagulopathy, adult respiratory distress syndrome and pulmonary thromboembolism.     

Ocular manifestations of a metastatic adenocarcinoma in a horse

A 10‐year‐old German Warmblood gelding was referred to the Equine Department of the Vetsuisse Faculty, University of Zurich, Switzerland, for an iris mass OD, lethargy, intermittent fever, and coughing. Ophthalmic examination revealed a 7 × 9 mm raised, fleshy, whitish to pinkish, vascularized iris mass at the 2 o`clock position OD. Fundic examination showed multifocal round, brown to black, slightly raised lesions with indistinct margins and a surrounding hyperreflective zone OU. Physical examination revealed a temperature of 39.2 °C, sinus tachycardia, preputial and ventral edema, and an enlarged right mandibular lymph node. Results of a complete blood count and plasma biochemical profile showed mild anemia, leukocytosis, and thrombocytopenia. Severe splenopathy, moderate splenomegaly, and severe pulmonary pathology with nodules and large areas of consolidated lung parenchyma were observed on abdominal ultrasound and thoracic radiographs, respectively. Fine needle aspirates of the enlarged mandibular lymph node showed malignant epithelial neoplastic cells. The horse was euthanized because of the poor prognosis and subsequently underwent postmortem examination. Macroscopic necropsy and histopathology revealed an adenocarcinoma of suspected pulmonary origin with involvement of eyes, heart, liver, kidneys, spleen, diaphragm, skeletal muscles, mandibular, pulmonary, and internal iliac lymph nodes. Metastatic adenocarcinoma should be considered as a differential diagnosis in horses with iris masses, multifocal chorioretinal infiltrates, and clinical signs that conform to a paraneoplastic syndrome.     

Paraneoplastic syndromes

A paraneoplastic syndrome is a disease or symptom that is a consequence of the presence of neoplasia, but is not due to the local presence of neoplastic cells. The pathophysiology of paraneoplastic syndromes is complex. Paraneoplastic syndromes may precede the detection of an active malignancy, and thorough investigation is therefore warranted to determine the cause of any clinical sign whose cause is not immediately apparent.     

Degenerative myelopathy in a German shepherd

A 9-year-old male German Shepherd had marked stumbling, staggering and weakness in both rear limbs. Pelvic radiographs revealed only mild hip dysplasia, while survey spinal radiographs and a myelogram revealed only areas of possible pachymeningitis. Results of CSF analysis were normal. Degenerative myelopathy was suspected, but a mitogen response assay failed to confirm this diagnosis. Another mitogen response assay, performed several months later, again failed to indicate degenerative myelopathy as the cause of clinical signs. The dog's condition worsened and the animal was euthanized. At necropsy, classic histopathologic lesions of degenerative myelopathy were noted in the thoracic spinal cord.     

ULTRASONOGRAPHIC FEATURES OF CANINE HEPATIC NODULAR HYPERPLASIA

Hepatic nodular hyperplasia is a benign, usually clinically inapparent, proliferative lesion commonly found at necropsy in older dogs. Three examples of hepatic nodular hyperplasia are described in dogs with clinical signs compatible with hepatic disease in which ultrasonography revealed a variety of echotextural changes in the liver similar to those reported in primary or secondary hepatic neoplasia. In subsequent in vitro ultrasonographic studies of hepatic nodular hyperplasia lesions detected at necropsy in dogs without clinical signs of hepatic disease, only subtle echotextural changes were seen. Hence, hepatic nodular hyperplasia may be inapparent in vivo in many dogs. Hepatic nodular hyperplasia is a potentially confusing sporadic finding which must be considered by ultrasonographers examining dogs with clinical signs of hepatic disease. The diagnosis of hepatic neoplasia should not be made on the basis of ultrasonographic findings alone.     

Ultrasound-Guided Fine-Needle Aspiration of Focal Parenchymal Lesions of the Lung in Dogs and Cats

Ultrasound-guided fine-needle aspiration (FNA) of the lung was performed on 16 dogs and 3 cats with consolidated pulmonary lesions or masses identified on thoracic radiographs. The cytologic results from the FNA were confirmed by histopathology, response to treatment, or microscopic identification of Blastomyces organisms. Neoplasia was identified correctly by FNA cytology in 10 of 11 animals, and no false positive results occurred, yielding a positive predictive value of 100%. Of 8 animals with infectious disease, 5 of 6 had blastomycosis and 1 had a bacterial infection, based on cytologic evaluation. Eight animals required sedation for the procedure, and none had clinical complications. We conclude that ultrasound-guided FNA of pulmonary mass lesions is an inexpensive, safe, and accurate method for diagnosing blastomycosis or neoplasia, especially carcinomas, in dogs and cats.     

Pulmonary lesions in cats with diabetes mellitus

Diabetes mellitus (DM) is a common endocrinopathy of cats and humans. Although few studies have examined the effects of DM on the pulmonary system, changes in pulmonary function and immunology in humans with type I and II diabetes, and pulmonary lesions in a murine diabetic model have been documented. Our objective was to determine whether pulmonary lesions occurred in cats with DM. Medical records and necropsy evaluations of 42 cats with DM were compared with those of 45 age-matched, nondiabetic cats for the presence of clinical evidence of respiratory disease and pulmonary histopathological findings at the time of necropsy. No statistical difference was noted in the presence of clinical evidence of respiratory disease between cats with diabetes and control cats. Nevertheless, there was a significant association between the presence of abnormal pulmonary histopathology and DM (P = .018, odds ratio = 3 inclusive of all cats; P = .005, odds ratio = 5 when non-DM cats with overt clinical evidence of respiratory disease were excluded). Pulmonary abnormalities detected by histopathological examination in cats with diabetes included congestion and edema, histiocytosis, pneumonia, smooth muscle hypertrophy, fibrosis, mineralization, neoplasia, and type II pneumocyte hyperplasia. The observed association between DM and pulmonary lesions in cats, independent of clinical evidence of respiratory disease, emphasizes the need for careful assessment of the respiratory tract in sick cats with diabetes.     

Comparison of thoracic radiographs and single breath-hold helical CT for detection of pulmonary nodules in dogs with metastatic neoplasia

Imaging studies in people indicate that x-ray computed tomography (CT) is a more sensitive technique than thoracic radiography for the detection of pulmonary metastasic neoplasia. Systematic studies comparing CT and thoracic radiographic techniques in veterinary patients have not been performed. The present retrospective study was designed to directly compare the efficacy of these 2 techniques in detecting pulmonary nodules in dogs. Eighteen dogs with histologically confirmed pulmonary metastatic neoplasia had contemporaneous thoracic radiographs and pulmonary CT scans compared. Quantitative analyses included estimation of pulmonary nodule size, number, and lobar distribution on thoracic radiographs and CT images. Only 9% of CT-detected pulmonary nodules were identified on thoracic radiographs (P < .003). The lower size threshold was approximately 1 mm to detect pulmonary nodules on CT images and 7-9 mm to reliably detect nodules on radiographs (P < .0001). Additionally, pulmonary nodules were detected in a significantly greater number of lung lobes using CT as compared with thoracic radiographs (P < .0001). These data indicate that CT is significantly more sensitive than thoracic radiography for detecting soft-tissue nodules in dogs. As such, thoracic CT should be considered in any patient with neoplasia that has potential for pulmonary metastasis to more reliably stage the disease, particularly when accurate characterization of the extent and distribution of pulmonary metastatic disease affects therapeutic planning.