Tuberculose no sistema nervoso central de bovinos na Paraíba

This paper describes six cases of tuberculosis in the central nervous system (CNS) of cattle in the state of Paraíba in northeastern Brazil. We reviewed the autopsy reports of 851 bovine necropsies performed from 2003 to 2016. Seventy-three (8.6%) cattle were diagnosed with tuberculosis and six showed lesions in the CNS. Three cases affected cattle up to two-year-old and other three affected adults. Three cattle presented exclusively nervous signs, two had respiratory signs and weight loss and one did not present any clinical signs. At necropsy, five cattle had thickening of the leptomeninges of the cerebellum, pons, obex, spinal cord and cortex, mainly, in the region near the brain basilar Willis´ circle. Another animal, presented a single focal lesion in the cerebellum. Microscopically we observed moderate to severe granulomatous meningitis and encephalitis. Five cattle presented lesions in the lungs and mediastinal lymph nodes and three of them had disseminated lesions in other organs. In all cattle acid-fast bacilli were observed in the lesions and marked positive for immunohistochemistry with polyclonal antibody anti-Mycobacterium tuberculosis. It is concluded that bovine tuberculosis of central nervous system occurs sporadically in Paraíba, in cattle of different ages, most of them with disseminate lesions in other organs. The location of the lesions suggests that the agent invaded the brain by hematogenous route through the circle of Willis.Descrevem-se seis casos de tuberculose no sistema nervoso central (SNC) em bovinos, no semiárido da Paraíba. Foram revisados os laudos de um total de 851 necropsias de bovinos realizadas no período de 2003 a 2016. Destes, 73 (8,6%) foram diagnosticados com tuberculose e seis apresentavam lesões no SNC. Três casos ocorreram em bovinos de até dois anos de idade e três em bovinos adultos. Três bovinos apresentaram exclusivamente sinais nervosos, dois tinham sinais respiratórios e perda de peso e um não apresentava nenhum sinal clínico. Macroscopicamente, em cinco bovinos, havia espessamento das leptomeninges do cerebelo, medula espinhal, ponte, obex, colículos e córtex, principalmente, na região basilar encefálica próxima ao polígono de Willis. Em apenas um bovino houve a presença de tubérculo único no cerebelo. Microscopicamente observou-se moderada a acentuada meningite e encefalite granulomatosa. Cinco bovinos apresentaram lesões pulmonares e nos gânglios mediastínicos e três deles tinham lesões disseminadas em outros órgãos. Em todos os bovinos foram encontrados bacilos ácido-álcool resistentes intralesionais e todos tiveram marcação positiva na técnica de imuno-histoquímica com anticorpo policlonal anti-Mycobacterium tuberculosis. Conclui‑se que a tuberculose do sistema nervoso central de bovinos ocorre de forma esporádica na Paraíba, principalmente em bovinos com lesões disseminadas em outros órgãos. Sugere-se que a disseminação do agente ocorre pela via hematógena, possivelmente através do polígono de Willis

Amebiasis in a Backyard Red-Foot Tortoise (Chelonoidis carbonaria)

Background: Amebiasis is a parasitic infection caused by obligate or facultative amoeboid protozoans, as well as free-living forms. The genus Entamoeba includes both pathogenic and commensal species that can affect humans and animals. Entamoeba histolytica is the most important species associated with intestinal and extraintestinal infections in humans, while Entamoeba invadens is considered the most common and serious pathogen to many reptile species, including lizards, snakes and crocodilians. The aim of this manuscript is to report a case of amebiasis in a backyard red-foot tortoise in northeastern Brazil.Case: A 10-month-old male red-foot tortoise (Chelonoidis carbonaria) was presented at the Animal Pathology Laboratory of the Veterinary Hospital of Federal University of Campina Grande for necropsy with a 1-week history of anorexia, apathy, and reluctance to move. According to the owner, the animal suffered from heat stress in the backyard, where it was housed with another male red-foot tortoise. At post-mortem examination, there were approximately 1 mL of yellowish viscous transudate in the coelomic cavity. The liver was large, with rounded edges and multifocal to coalescing yellowish areas in the subcapsular surface. When cut, the parenchyma was more friable and yellowish. At the opening of the small intestine, the mucosa was thickened, reddened, and contained many variably sized, dark red ulcers with depressed and hemorrhagic centers. Histopathology of the liver reveals diffuse macro and microvacuolar degeneration of the hepatocyte cytoplasm, often displacing the nucleus peripherally (fatty degeneration). There were extensive and multifocal areas of necrosis characterized by shrunken, hypereosinophilic and pyknotic hepatocytes. Amebic trophozoites were seen through the areas of necrosis and degeneration and the morphological features were suggestive of the genus Entamoeba. In the portal triads and slightly extending to the sinusoidal spaces, there is a moderate inflammatory infiltrate of macrophages, lymphocytes, plasma cells and rare heterophils. There were amebic trophozoites and thrombi in hepatic vessels, and mild intracanalicular cholestasis. The small intestine contained areas of transmural necrosis and ulceration associated with inflammatory infiltrate of macrophages, lymphocytes and plasma cells. The ulcers were covered by a thick fibrinonecrotic exudate mixed with a varying number of heterophils and macrophages. The submucosa contained hemorrhage and edema. Similar amebic trophozoites were found within the mucosa and submucosa, and also detected in the lumens of blood vessels at the submucosa. The amebic trophozoites, seen in the liver and intestine, were intensely Periodic acid–Schiff positive.Discussion: The diagnosis of amebiasis was based on the epidemiological, clinical and anatomopathological findings. Amebiasis is a well-recognized disease that usually is diagnosed post-mortem in numerous species of reptiles. Unfortunately, there are no scientific articles describing these cases in Brazil. In reptiles, the major pathogenic specie is Entamoeba invadens, while several other species are considered non-pathogenic, such as E. barreti, E. insolita, E. terrapinae, E. ctenosaurae, and E. knowlesi, among others. Although cultivation of E. invadens was not undertaken, the anatomopathological findings and the morphological appearance of the agent is highly suggestive of infection with this organism. In conclusion, amebiasis is a severe infectious disease that can affect young red-footed tortoises under adverse environmental conditions. Clinical signs are nonspecific and may be difficult to identify. The diagnosis is usually made post-mortem by anatomopathological findings and the morphological appearance of the agent

Nocardiosis in Cats - Clinical, Anatomopathological and Morphotintorial Characteristics

Background: Nocardiosis is an infectious bacterial disease that can cause cutaneous/ subcutaneous, pulmonary and systemic lesions in different species of domestic animals. The type of transmission occurs through mechanical lesions on the skin or contamination of wounds, in cases of skin involvement, inhalation of aerosols and ingestion of contaminated materials are involved in the pathogenesis of the respiratory and digestive form of the disease. This paper described 4 cases of nocardiosis in cats, addressing the clinical, anatomopathological and morphotintorial characteristics of Nocardia sp.Cases: Four cases of nocardiosis in cats were reviewed, in which data related to breed, sex, age, origin, clinical signs, macroscopic and histological lesions described in necropsy protocols were evaluated. The histological tissue sections stained with Hematoxylin and Eosin (HE) were evaluated in order to characterize the inflammatory response in each case. In addition, paraffin blocks of fragments from affected organ were selected to perform special histochemical staining techniques of Grocott Methenamine Silver (GMS), modified Ziehl-Neelsen, Gram Brown-Brenn and Giemsa stain which are the most characterized techniques used for histopathological diagnoses and it was also used an immunohistochemical test with polyclonal antibody anti-Nocardia sp. (non-commercial). The animals were adults of both sexes, mixed breed, not castrated and semi-domesticated. Neither immunosuppressive factors nor concomitant diseases were identified in the cases studied. The main clinical signs were apathy, anorexia, dehydration, phlegmon and draining tracts. Macroscopically, skin / subcutaneous tissue (3/4), skeletal muscle (2/4), lymph nodes (2/4), liver (2/4), omentum (1/4), spleen (1/4) were affected. In addition, it could be noted that mandibular bone (1/4), pleural tissue (1/4), left testicle (1/4) and Central Nervous System (CNS) (1/4) were also affected by this disease. Microscopically, regarding all cases, there was a pyogranulomatous inflammation in the affected organs. With respect to cases 1, 3 and 4, filamentous, branched, slightly basophilic structures in loose or individual aggregates in the interior of the pseudo-rosettes and in the necrotic areas were observed in the HE-stained tissue sections. In all cases submitted to special histochemical techniques, filamentous, branched, individual or loose aggregate structures were observed, the samples were impregnated with silver, and bacteria appear as blue using the Brown-Brenn Gram technique, and stained red in the modified Ziehl-Neelsen, and stained faintly pink in Giemsa stain. The bacteria were observed mainly in the border of the pyogranulomas, in the center of the pseudo-rosettes and in the necrotic areas, being compatible with the infection by Nocardia sp. All cases were positive for immunohistochemistry (IHC).Discussion: Nocardiosis was diagnosed in all cats in this study based on the anatomopathological findings associated with the visualization of the agent and its morphotintorial characteristics by using special histochemical stains and being confirmed by IHC. It occurs mainly in the cutaneous and/or subcutaneous tissues, with systemic involvement and death of the affected animals, in addition to affecting bone tissue considered an uncommon site for the disease. The diagnosis can be established based on the anatomopathological findings associated with the morphotintorial characteristics by using special histochemical stains, which are important for evidencing and morphologically characterizing the agent, as well as being confirmed by IHC.Keywords: disease in cat, pyogranulomatous inflammation, Nocardia sp.Título: Nocardiose em gatos - achados clínicos, anatomopatológicos e morfotintoriais Descritores: doença de gato, inflamação piogranulomatosa, Nocardia sp. 

T-cell Lymphoma in the Nasal Cavity in Goat

Background: Lymphomas are considered uncommon in goats, being the multicentric form with the highest number of cases for the species. Primary intranasal lymphomas are often diagnosed in dogs, cats, and humans. In the literature, there is only a description of a multicentric case involving the frontal sinuses and mucosa of the nasal cavity in a goat; therefore, it is important to describe unusual cases of this disease for the inclusion of new clinical and pathological characteristics in the ruminant clinic medicine. The objective of this work is to describe a case of T-cell lymphoma in the nasal cavity of a young goat.Case: The animal had dyspnea and respiratory noise for 15 days. Clinical examination showed nodulation in the right nasal cavity associated with serosanguinous secretion. Tracheostomy was performed; however, after 30 days the animal was euthanized. A sagittal plane of the head showed a pinkish-gray mass in the right and left nasal cavity, with a smooth, multilobulated surface, smooth adhering to the rostral portion of the dorsal concha and occluding the dorsal nasal meatus. Submandibular lymph nodes were slightly enlarged. Histopathological examination of the nasal cavity revealed a non-encapsulated, poorly delimited and ulcerated tumor composed of round cells arranged in a mantle supported by a discrete fibrovascular stroma extending the mucosa and lamina propria. Cells were round with sparse, eosinophilic and poorly delimited cytoplasm. Nuclei varied from round to elongated with condensed chromatin and evident nucleoli. Occasionally, aberrant nuclei, reniform shape and multinucleated cells were seen. Pleomorphism was moderate characterized by anisocytosis and anisocariosis. Typical and atypical mitosis were frequent (0-4 per field of highest magnification [400x]). Amidst the neoplasm, there were multifocal areas of necrosis and hemorrhage associated with a mild lymphocytic inflammatory infiltrate. Immunohistochemistry showed positive immunostaining for Vimentin antibodies and CD3, and negative for pan CK and CD20.Discussion: The lymphomas immunophenotyping is little used when it comes to farm animals, and there are few studies that use this technique for the definitive diagnosis of these neoplasms for small ruminants. The use of this technique must be considered in each case, in order to determine the pathogenesis, the accurate diagnosis and the origin of the neoplastic lymphocytes. In goats, T-cell lymphomas are the most diagnosed, although cases of multicentric B-cell lymphomas with ocular involvement have been diagnosed. In view of the clinical picture of the case described, infectious rhinitis already described in goats, such as aspergillosis and protothecosis, should be included as differential diagnoses. However, the anatomopathological findings facilitate the direction of the diagnosis, since infectious rhinitis presents as nodules / ulcerated masses or focal areas of necrosis associated with purulent secretion and in the histopathological examination it is possible to observe the intralesional etiological agents. In addition, the enzootic ethmoidal tumor must be included, as it has similar clinical signs and affects young animals, but they are adenomas/adenocarcinomas that affect the ethmoidal nasal shells induced by a retrovirus. Lymphomas in the caprine species are rare in the Northeastern semi-arid, but that in the present diagnostic routine occasionally occurs, being important the first description of its nasal shape for its inclusion in the differential diagnoses of diseases that present with clinical obstruction and dyspnea for the species. Keywords: hematopoietic neoplasia, immunophenotyping, lymphocytes, dyspnea.Descritores: neoplasia hematopoietica, imunofenotipagem, linfócitos, dispneia.Título: Linfoma de células T na cavidade nasal de caprino.

Thalamic Melanosis in Goats

Background: Melanosis is a blackened pigmentation resulting from the accumulation of melanocytes in tissues that are not normally pigmented. This change in the color of the organs occurs due to the agglomeration of melanocytes originating from abnormal migration during embryogenesis and does not cause dysfunction to the affected organ. Although melanosis frequently occurs in several species and affects several organs such as the brain and spinal cord leptomeninges, involvement in the thalamus region is unusual. The objective of this work was to report two cases of thalamic melanosis in goats, determining the pathological and histochemical aspects that assist in the diagnosis of this condition.Cases: Two cases of thalamic melanosis in goats were diagnosed. In both cases, the animals had no nervous history disease and clinical signs. The cause of death in cases 1 and 2 was established based on anatomopathological findings and clinical signs being diagnosed with mycoplasmosis and asphyxia, respectively. After fixing and making cross-sections of the brain, a focal lengthy blackened area was observed on the thalamus surface in both cases. Microscopically, lesions in the brain were similar in both cases and exclusively affected the thalamus. These cells had abundant cytoplasm, well delimited with brownish granular pigment. The nuclei were difficult to visualize and in some cells, it was rounded, well-defined, morphologically compatible with melanocytes. Melanocytes were mainly distributed around neurons and often distended the perivascular space of multiple blood vessels. In Fontana Masson staining, the granules in the cytoplasm of these cells stained strongly black. The Prussian Blue, Periodic Acid- Schiff's, Von Kossa, and Giemsa stains were negative, and the pigment remained brown. In the unstained slides, assembled after the deparaffinization and clarification process, it was observed the permanence of cells with blackish-brown pigment in the cytoplasm. In immunohistochemistry, strong immunostaining of pigmented cells with the Anti-MelanA antibodies was observed in both cases.Discussion: The diagnosis of thalamic melanosis in goats was carried out based on the characteristic pathological findings, in which melanin pigments were demonstrated and identified through HE, Fontana-Masson staining, and unstained slides and confirmed by the IHC. The use of complementary histochemical techniques was fundamental for the classification of the pigment as melanin, demonstrating to be an accessible and reliable tool for the diagnosis of pathological processes that lead to the accumulation of pigments and or material in the tissues. The occurrence of melanin in the thalamus may be associated with a failure in the migration of melanoblasts, which would go to the optical pathways or to the thalamus. This erratic migration of melanoblasts can be explained by the fact that the forebrain is the embryogenic origin of the optic and diencephalon pathways. Macroscopically, thalamic melanosis must be differentiated mainly from neoplastic processes such as melanoma and hemangiosarcoma, pigmented fungus infections, Phalaris angusta poisoning, listeriosis, neurocutaneous melanosis, and neuromelanin. It was concluded that thalamic melanosis is an uncommon alteration in goats and although it has been diagnosed as an incidental necropsy finding, should be included in the differential diagnosis of diseases that affect the central nervous system, especially those that have a color change associated with the deposition of pigments in the tissues. Keywords: melanin, necropsy findings, pigment, thalamus.Descritores: melanina, achados de necropsia, pigmento, tálamo.Título: Melanose talâmica em caprinos.

Systemic Toxoplasmosis in Kittens

Background: Toxoplasmosis is a worldwide disease that affects virtually all species of warm-blooded animals. The felids, domestic and wild, are considered the definitive hosts of the protozoan. In Brazil, Toxoplasma gondii infection has been diagnosed in horses, goats, primates, dogs and cats. In the backlands of Paraíba, the disease has been sporadically reported affecting dogs with canine distemper and swine, but cases of systemic toxoplasmosis in cats have not yet been described. The aim of the present study was to describe the main epidemiological, clinical and anatomopathological aspects of two cases of systemic toxoplasmosis in kittens.Cases: Two kittens were affected with three (cat 1) and six (cat 2) months old, females, and crossbreed. The kittens had not been vaccinated or dewormed, and were raised with other cats in a peridomiciliary regime in a rural area in the backlands of Paraíba. Cat 1 was thin, apathetic, dehydrated, tachypneic and with pale mucous membranes. Cat 2, showed inappetence, apathy, jaundice, fever, dehydration, dyspnea and abdominal breathing pattern. At necropsy, non-collapsed, shiny, reddish lungs with multifocal whitish areas, punctuated or nodular, measuring from 0.1 to 0.3 cm in diameter, were found on the pleural surface and parenchyma. The livers were pale, with lobular pattern accentuation, and reddish depressed multifocal areas randomly distributed on the capsular surface. Histologically, multifocal to coalescent areas of necrosis, moderate (cat 1) or marked (cat 2), associated with intralesional bradyzoites and tachyzoites and variable lymphoplasmacytic infiltrate were observed. In cat 2, numerous bradyzoites were visualized in the gray matter of the left cerebral hemisphere (temporal and parietal lobes), sometimes associated with a moderate lymphoplasmacytic inflammatory infiltrate. In the perivascular spaces of the cerebral cortex, discrete inflammatory lymphoplasmacytic infiltrate (perivascular cuffs) were observed. Immunohistochemistry for T. gondii revealed strong immunolabelling of the parasitic organisms.Discussion: The diagnosis of systemic toxoplasmosis was established based on anatomopathological findings and histomorphological characteristics of the agent, being confirmed by immunohistochemistry. The systemic disease occurs most often in young animals, especially immunocompromised or immunologically immature neonates. In these kittens, it was not possible to determine the presence of an intercurrent immunosuppressive condition; however, both animals were kept in the peridomiciliary regime and were in contact with other cats, which may have acted as a source of infection. Besides, both kittens were raised in rural environments, condition that associated with the usual predatory behavior of this species may have favored the ingestion of infected intermediate hosts. The clinical signs of the disease vary considerably depending on the location and severity of the lesions. Infection in cats usually is asymptomatic or promotes self-limiting diarrhea as a result of protozoal enteroepithelial replication; but in some cases the protozoan can spread to other tissues, determining the occurrence of necrotic processes, dysfunction and clinical manifestations. Systemic toxoplasmosis occurs sporadically in kittens in the backlands of Paraíba, with pulmonary and hepatic clinical manifestations. The histopathological findings are characterized by tissue necrosis and lymphoplasmacytic inflammation associated with intralesional protozoa. The diagnosis can be established based on the histomorphologic characteristics of the agent and confirmed by immunohistochemistry