Pathological findings and differential diagnoses of lymph node diseases in slaughtered cattle in Brazil: A study of 2000 samples.

Slaughterhouse inspections play a crucial role in the sanitary control of zoonoses and foodborne diseases. This study aimed to identify and analyze the frequencies of lymph node diseases in cattle slaughtered for human consumption, using the samples sent to the anatomic pathology service of the Federal Laboratory for Agricultural Defense (Laboratório Federal de Defesa Agropecuária), Minas Gerais, Brazil, from January 2015 to September 2022. In total, 2000 lymph node samples were analyzed, and additional information was individually retrieved. Lesions were most frequently identified in thoracic lymph nodes. Bacterial isolation and quantitative polymerase chain reaction (qPCR) were performed using samples suspected of tuberculosis. Tuberculosis cases accounted for 89.3% of the samples. Histopathology was more sensitive than other ancillary tests for diagnosing tuberculosis. Paraffin-embedded tissues from lymphoma cases were subjected to immunophenotyping using anti-CD3 and anti-CD79a immunohistochemistry. Frozen and/or paraffin-embedded tissues from lymphoma cases were used to identify the enzootic bovine leukosis (EBL) retrovirus through qPCR. Other diagnoses included primary (T- and B-cell lymphoma) and metastatic neoplasms (squamous cell carcinoma, pulmonary adenocarcinoma, undifferentiated carcinoma, undifferentiated adenocarcinoma, undifferentiated sarcoma, undifferentiated round cell tumor, mesothelioma, hepatic carcinoid, meningioma, and seminoma), actinogranulomas (pyogranulomatous lymphadenitis [actinobacillosis and actinomycosis]), idiopathic lymphadenitis (neutrophilic and/or histiocytic, granulomatous, and suppurative), and miscellaneous nonspecific lymphadenopathies (depletion/lymphoid atrophy, lymphangiectasia, erythrocyte drainage, parasitic eosinophilic lymphadenitis, follicular hyperplasia, and toxic granulomatous lymphadenitis). The combination of histopathology with complementary techniques is important for successful diagnosis, especially in complex cases of high epidemiological, economic, and zoosanitary importance, such as tuberculosis and EBL.

Classification of lymphoma in cats and its relationship with the detection of feline leukemia vírus proviral DNA / Classificação do linfoma em gatos e sua relação com a detecção do DNA pró-viral do vírus da leucemia felina

In this retrospective and prospective study, histopathological and immunohistochemical analyses of 62 cases of lymphomas in cats were performed to classify the anatomic forms and subtypes, according to the WHO guidelines, and correlate it to FeLV proviral DNA detected using PCR. The most common anatomical form was gastrointestinal (40.3%, 25/62), followed by multicentric (29%, 18/62), mediastinal (17.7%, 11/62) and extranodal (12,9%, 8/62). Among the lymphoma subtypes, diffuse large B-cell lymphoma (DLBCL) (30.6%, 19/62) was the most commonly diagnosed followed by peripheral T-cell lymphoma (PTCL) (29%, 18/62) and enteropathy associated T-cell lymphoma type 2 (14.5%, 9/62). DNA extraction from paraffin-embedded neoplastic tissue was obtained in 28 cases and FeLV proviral DNA was detected by PCR, in 23 of these. Of the cases presenting with FeLV proviral DNA, nine (32%) were of the multicentric form, five (22%) of the mediastinal and extranodal forms and four (17%) of the gastrointestinal form. The most frequent subtypes with FeLV proviral DNA, independent of the anatomical form, were DLBCL (39.1%, 9/23) and PTCL (34.7%, 8/23). The presence of the FeLV proviral DNA in 23 cats of this study, probably had association with the multicentric form of lymphoma and higher occurrence in the DLBCL and PTCL subtypes.

Neste estudo retrospectivo e prospectivo, análises histopatológicas e imuno-histoquímicas de 62 casos de linfomas em gatos foram realizadas para classificar as formas anatômicas o e subtipos do linfoma, de acordo com as diretrizes da OMS. Além disso, foi realizada a extração de DNA dos tumores incluídos na parafina para obtenção de DNA pró-viral do FeLV por PCR, e relacionada com os exames anteriores. A forma anatômica mais comum foi a gastrointestinal (40.3%, 25/62), seguida pela multicêntrica (29%, 18/62), mediastinal (17,7%, 11/62) e extranodal (12,9%, 8/62). Entre os subtipos de linfoma, o linfoma difuso de grandes células B (DLBCL) (30.6%, 19/62) foi o mais comumente diagnosticado, seguido por linfoma de células T periférico (PTCL) (29%, 18/62) e o linfoma de células T associado a enteropatia tipo 2 (14.5%, 9/62). A extração de DNA de tecido neoplásico emblocado em parafina foi obtida em 28 casos e o DNA pró-viral de FeLV foi detectado por PCR, em 23 deles. Dos casos com DNA pró-viral do FeLV, nove (32%) eram da forma multicêntrica, cinco (22%) das formas mediastinal e extranodal e quatro (17%) da forma gastrointestinal. Os subtipos mais frequentes com DNA pró-viral do FeLV, independente da forma anatômica, foram DLBCL (39.1%, 9/23) e PTCL (34.7%, 8/23). A presença do DNA pró-viral do FeLV em 23 gatos deste estudo, provavelmente teve associação com a forma multicêntrica do linfoma e maior ocorrência nos subtipos DLBCL e PTCL.

Pathology of severe urolithiasis in a flock of egg-laying hens

Fourteen, 31-week-old Lohmann white layers from a flock of 30,000 chickens had a history of apathy, and a drop in egg production. Clinical signs were observed in approximately 40% of the flock, and lasted for three months. Fourteen hens were euthanized for post-mortem examinations. Macroscopic findings included marked atrophy and loss of renal lobes along with compensatory renal hypertrophy of the contralateral lobe. Ureters were markedly dilated and filled with mucus and/or with molded white to yellow-grey uroliths that obliterated the lumen. At histopathology, the uroliths inside ureters and tubules were composed of concentrically arranged mineralized concretions, as well as urates associated with heterophilic infiltrations and epithelial hyperplasia. Renal parenchyma adjacent to obstructed ureters was compressed with tubules replaced by fibrous tissue. Multifocal interstitial lymphocytic nephritis, proteinuria and membranoproliferative glomerulonephritis were also found. Heterophilic and caseous ureteritis associated with numerous Gram-positive coccoid bacteria occurred in three chickens. Immunohistochemistry for avian coronavirus was negative. This negative result along with the case history indicated that water restriction was the most likely cause of mortality. This condition resulted in significant economic loss for this farmer.(AU)

Pathology of severe urolithiasis in a flock of egg-laying hens

Fourteen, 31-week-old Lohmann white layers from a flock of 30,000 chickens had a history of apathy, and a drop in egg production. Clinical signs were observed in approximately 40% of the flock, and lasted for three months. Fourteen hens were euthanized for post-mortem examinations. Macroscopic findings included marked atrophy and loss of renal lobes along with compensatory renal hypertrophy of the contralateral lobe. Ureters were markedly dilated and filled with mucus and/or with molded white to yellow-grey uroliths that obliterated the lumen. At histopathology, the uroliths inside ureters and tubules were composed of concentrically arranged mineralized concretions, as well as urates associated with heterophilic infiltrations and epithelial hyperplasia. Renal parenchyma adjacent to obstructed ureters was compressed with tubules replaced by fibrous tissue. Multifocal interstitial lymphocytic nephritis, proteinuria and membranoproliferative glomerulonephritis were also found. Heterophilic and caseous ureteritis associated with numerous Gram-positive coccoid bacteria occurred in three chickens. Immunohistochemistry for avian coronavirus was negative. This negative result along with the case history indicated that water restriction was the most likely cause of mortality. This condition resulted in significant economic loss for this farmer.