Paula Rodrigues de Almeida

Surto de intoxicação por sal em suínos em Santa Catarina

A total of 70 pigs were affected and died due to salt poisoning in two farms in southern Brazil. The only source of drinking water available to the pigs was whey from cheese salting process. One day after receiving the whey, animals started getting sick and showed excessive salivation, opisthotonus, paddling, and cyclic tremors. At necropsy of three pigs, two of them presented flattening of gyri and the other one presented cortical telencephalon edema. Microscopically, severe diffuse neuronal necrosis in telencephalic laminar cortex, Alzheimer type II astrocytes (AIIA), eosinophilic and lymphocytic perivascular cuffing apart of perivascular edema were observed. Weak or absent anti-glial fibrillary acidic protein (GFAP) immunolabeling was associated with positive immunostaining for S-100 in AIIA cytoplasm. Concentration of sodium in serum and liquor samples from dead pigs resulted 140 and 156mmol/L, respectively.

Hepatite infecciosa canina em cães naturalmente infectados: achados patológicos e diagnóstico imuno-histoquímico

Twenty-three dogs with infectious canine hepatitis (ICH) were analyzed, based on general data, clinicopathological findings, and immunohistochemistry. The main gross lesions were hepatic paleness (17/23), hepatomegaly (10/23), and hemorrhage (21/23). Gallbladder edema (11/23), fibrinous material on the hepatic capsular surface (8/23), and jaundice (6/23) were also found. Severe hepatic necrosis was observed in association with amphophilic or basophilic intranuclear inclusions inside hepatocytes and endothelial cells (22/23). Splenic and nodal lymphoid necrosis and hemorrhage associated with small number of intranuclear inclusions inside reticuloendothelial cells were identified. Immunohistochemistry (IHC) was positive for adenovirus type 1 in all animals, with the best staining pattern occurring in the liver (23/23), brain (22/22), cerebellum (16/20), and kidney (16/21). Greater amount of viral antigen was identified in hepatocytes and vascular endothelial cells from the brain and glomerular tuft.

Granulomatous myelitis associated with hemorrhagic syndrome due to consumption of Vicia villosa by cattle

An unusual case of spontaneous Vicia villosa poisoning affected a 6-year-old Holstein cow. Although the most striking findings included a generalized hemorrhagic condition associated with granulomatous myelitis, histological lesions typically seen with the vetch-associated systemic granulomatous syndrome were also present. Prominent gross findings were bloody nasal and oral discharges, disseminated hemorrhages, and bloody feces. Generalized hemorrhages associated with infiltration of numerous organs by lymphocytes, plasma cells, macrophages, multinucleated giants cells, and eosinophils were the main microscopic findings. Anti-CD68 immunostaining confirmed the presence of moderate histiocytic infiltrate and multinucleated giant cells in the bone marrow. These changes in the bone marrow probably caused the generalized hemorrhagic changes described here.

Nested-PCR for the detection of Mycoplasma hyopneumoniae in bronchial alveolar swabs, frozen tissues and formalin-fixed paraffin-embedded swine lung samples: comparative evaluation with immunohistochemical findings and histological features

The diagnosis of Mycoplasma hyopneumoniae infection is often performed through histopathology, immunohistochemistry (IHC) and polymerase chain reaction (PCR) or a combination of these techniques. PCR can be performed on samples using several conservation methods, including swabs, frozen tissue or formalin-fixed and paraffin-embedded (FFPE) tissue. However, the formalin fixation process often inhibits DNA amplification. To evaluate whether M. hyopneumoniae DNA could be recovered from FFPE tissues, 15 lungs with cranioventral consolidation lesions were collected in a slaughterhouse from swine bred in herds with respiratory disease. Bronchial swabs and fresh lung tissue were collected, and a fragment of the corresponding lung section was placed in neutral buffered formalin for 48 hours. A PCR assay was performed to compare FFPE tissue samples with samples that were only refrigerated (bronchial swabs) or frozen (tissue pieces). M. hyopneumoniae was detected by PCR in all 15 samples of the swab and frozen tissue, while it was detected in only 11 of the 15 FFPE samples. Histological features of M. hyopneumoniae infection were presented in 11 cases and 7 of these samples stained positive in IHC. Concordance between the histological features and detection results was observed in 13 of the FFPE tissue samples. PCR was the most sensitive technique. Comparison of different sample conservation methods indicated that it is possible to detect M. hyopneumoniae from FFPE tissue. It is important to conduct further research using archived material because the efficiency of PCR could be compromised under these conditions.

Diarrhea caused by rotavirus A, B, and C in suckling piglets from southern Brazil: molecular detection and histologic and immunohistochemical characterization

Rotavirus (RV) is an important viral pathogen causing diarrhea in piglets and other mammals worldwide. We describe 34 cases from 4 diarrheal outbreaks caused by RV in unvaccinated farrowing units in southern Brazil from 2011 to 2013. We performed autopsy, histologic examinations, bacterial culture, RV immunohistochemistry (IHC), and enteric virus detection through molecular assays for rotavirus A, B, and C, transmissible gastroenteritis virus, porcine epidemic diarrhea virus, sapovirus, norovirus, and kobuvirus. Histologically, villus atrophy (29 of 34) and epithelial vacuolation (27 of 34) occurred in all 4 outbreaks. Cell debris in the lamina propria occurred in 20 cases, mostly from outbreaks A (8 of 11), C (4 of 6), and D (7 of 11). IHC was positive for RV in 21 of 34 samples. RT-PCR was positive for RV in 20 of 30 samples; RV-C was the most frequently detected RV (n = 17). Kobuvirus was detected in 11 samples, and, in 3 of them, there was single detection of this enteric virus.

Achados patológicos e imuno-histoquímicos em felinos domésticos com panleucopenia felina

Feline panleukopenia is an important infectocontagious disease of domestic feline, especially in animals under 1 year. This paper describes the clinical-pathological findings and the immunohistochemical diagnosis of 33 cases of feline panleukopenia. The most important clinical signs were vomiting, diarrhea, and anorexia. The main gross findings observed were reddening of intestinal mucosa (16/33), evidentiation of Peyer patches (14/33), and liquefied intestinal content (7/33). The most consistent histological findings were necrosis (33/33) and lymphohistiocytic inflammatory infiltrate in the intestinal mucosa (31/33), villus fusion (27/33) and villus atrophy (26/33). In the hematopoietic tissues, the findings were characterized mainly by necrosis and tissue depletion. Parvovirus positive immunohistochemichal results were obtained in 84.85% of the cases analyzed. The best organ for viral detection was the intestine, with 84.85% of labeling in the immunohistochemichal technique. The spleen showed the best result among lymphoid organs, with 47.37% of the sections positive. This study presents most important lesions in the small intestine and in lymphoid organs and the immunohistochemistry proved good results in the detection of parvovirus.