Comparative analysis of diagnostic methods and risk factors for Aelurostrongylus abstrusus infection in brazilian cats.

This study aimed to prospectively evaluate the risk factors of infection by Aelurostrongylus abstrusus in Brazilian cats with cough and/or radiographic changes, using as diagnostic tools the Baermann method (BM), polymerase chain reaction (PCR) of feces, bronchoalveolar lavage fluid (BALF), and cytology. Forty-three cats that were presented with cough or lung radiographic abnormalities compatible with bronchoalveolar disease were included in the study. After clinical evaluation, feces samples were collected to investigate lungworm parasitism through BM and PCR. BALF was performed to provide samples for cytology, bacteriology, and fungal culture. Stool PCR was considered the gold standard for diagnosis tests, and the other methods were evaluated by their agreement. PCR presented 74% (32/43) of positivity for A. abstrusus, while in the BM, 41% (18/43) were positive. BM showed sensitivity of 56.25% and specificity of 100% when compared with PCR. No larva was found in the cytological evaluation of 21 BALF samples. Lungworm is an important cause of bronchopulmonary disease in domestic cats in Brazil and should be included as a differential diagnosis when a cat is presented with cough or radiographic abnormalities. BM is a sensitive, non-invasive, and cheap technique to diagnose the disease, but it is not as sensitive as PCR.

Epidemiological and Pathological Characterization of Feline Injection Site Sarcomas in Southern Brazil.

Feline injection site sarcoma (FISS) is a mesenchymal neoplasm with highly malignant characteristics. These tumours originate in anatomical sites where there has been previous parenteral administration of medicinal substances or implantation of medical devices. The aim of this study was to investigate the epidemiological and pathological features associated with FISS in the southern region of Brazil. The database of the Department of Veterinary Pathology of the Federal University of Rio Grande do Sul was searched for excisional and incisional biopsy samples compatible with FISS submitted between 2007 and 2017. Biopsy reports were reviewed and epidemiological information, including breed, age and sex of affected cats, as well as gross findings including anatomical location and size of the tumour and the presence of tissue invasion, were extracted. Eighty-nine samples were selected based on the established criteria. Most animals were of undefined breed and were female cats with a median age of 10 years. Grossly, 84.8% of the tumours were >2 cm in diameter. Regarding anatomical location, 34.9% of the tumours were located in the subcutaneous tissue of the thoracic wall, 29.2% in the flank, 21.3% in the interscapular region and 14.6% in the limbs. Histologically, the tumours originated in the subcutaneous tissue and were diagnosed as malignant mesenchymal neoplasms. Most were compatible with fibrosarcomas, but variants with features of pleomorphic sarcoma or chondrosarcoma were recognized. All tumours exhibited areas of necrosis and peripheral inflammatory infiltrate, composed predominantly of lymphocytes, plasma cells and macrophages. The results of this study suggest the need for dissemination of information on FISS epidemiology and guidelines for management of this tumour to veterinarians in the region.

Multifocal Spinal Cord Nephroblastoma in a Dog.

A 1-year-old male American pit bull terrier was presented with a history of proprioceptive deficits and mild lameness of the right hindlimb, which progressed after 5 months to paraparesis, culminating in tetraparesis after 2 weeks. Necropsy findings were limited to the spinal cord and consisted of multiple, intradural, extramedullary, slightly red masses which produced segmental areas of medullary swelling located in the cervical intumescence, thoracolumbar column, sacral segment and cauda equina. Histological evaluation revealed a tumour, composed of epithelial, stromal and blastemal cells, with structures resembling tubules, acini and embryonic glomeruli. Immunohistochemical labelling for vimentin, cytokeratin and S100 was positive for the stromal, epithelial and blastemal cells, respectively. A final diagnosis of multifocal spinal cord nephroblastoma was established. This is the first report of such a tumour showing concomitant involvement of the cervicothoracic, thoracolumbar, sacral and cauda equina areas of the spinal cord.

Oxidative stress in dairy cows naturally infected with the lungworm Dictyocaulus viviparus (Nematoda: Trichostrongyloidea).

The aim of this study was to analyse the oxidative and anti-oxidant status in serum samples from dairy cows naturally infected by Dictyocaulus viviparus and its relation with pathological analyses. The diagnosis of the disease was confirmed by necropsy of one dairy cow with heavy infection by the parasite in the lungs and bronchi. Later, blood and faeces were collected from another 22 cows from the same farm to measure reactive oxygen species (ROS) levels, thiobarbituric acid-reactive substances (TBARS), catalase (CAT) and superoxide dismutase (SOD) activities on day 0 (pre-treatment) and day 10 (post-treatment with eprinomectin). Faecal examination confirmed the infection in all lactating cows. However, the number of D. viviparus larvae per gram of faeces varied between animals. Cows showed different degrees of severity according to respiratory clinical signs of the disease (cough and nasal secretion). Further, they were classified and divided into two groups: those with mild (n = 10) and severe disease (n = 12). Increased levels of TBARS (P < 0.001), ROS (P = 0.002) and SOD activity (P < 0.001), as well as reduced CAT activity (P < 0.001) were observed in cows with severe clinical signs of the disease compared to those with mild clinical signs. Eprinomectin treatment (day 10) caused a reduction of ROS levels (P = 0.006) and SOD activity (P < 0.001), and an increase of CAT activity (P = 0.05) compared to day 0 (pre-treatment). TBARS levels did not differ with treatment (P = 0.11). In summary, increased ROS production and lipid peroxidation altered CAT and SOD activities, as an adaptive response against D. viviparus infection, contributing to the occurrence of oxidative stress and severity of the disease. Treatment with eprinomectin eliminated the infection, and thus minimized oxidative stress in dairy cows.