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.

Strongyloidiasis in a Puppy in Northeastern Brazil

Background: Strongyloides stercoralis is a nematode that causes intestinal infection in vertebrate hosts, especially in humans and dogs. The species S. stercoralis is responsible for chronic and asymptomatic infections in adult dogs or serious infections in puppies and immunosuppressed animals. In Brazil, natural infection in dogs was demonstrated by coproparasitological and serological methods, however, there are no reports that address the clinicopathological characteristics of the infection in the canine species. Thus, this paper aims to describe the epidemiological, clinical and pathological aspects of S. stercoralis infection in a puppy in Northeastern Brazil.Case: A puppy female Chihuahua was referred to the Animal Pathology Laboratory of the Veterinary Hospital of the Federal University of Campina Grande for necropsy with a historic of severe respiratory symptoms and gastrointestinal changes that included sanguineous diarrhea and vomiting that evolved to death in 5 days. Grossly, there was a moderate amount of slightly reddish fluid in the thoracic cavity. The lungs remained expanded with a smooth, shiny, and diffusely reddish pleural surface interspersed with multifocal and blackened coalescent areas. Upon cutting, a moderate amount of slightly yellow foamy liquid flowed from the airways and trachea. In the duodenum, the mucosa was diffusely reddened. Histologically, there were multifocal to coalescent areas of moderate interalveolar accumulation of fibrin, edema and hemorrhage in the lung surrounded by an inflammatory infiltrate composed of foamy macrophages associated with numerous parasitic structures in longitudinal and transverse sections in the alveolar lumen and pleural surface. In the duodenum, we observed flattening with diffuse and moderate fusion of the villi and multifocal areas of mucosal erosion. The crypts were moderately dilated, covered by attenuated epithelium, with numerous longitudinal and transversal sections of adult nematode parasites, larvae and eggs associated with inflammatory lymphplasmocytic infiltrate in the lamina propria. The morphological characteristics were compatible with the nematode S. stercoralis.Discussion: The diagnosis of strongyloidiasis was performed by means of microscopic lesions associated with parasitic structures morphologically compatible with the nematode S. stercoralis. This species is responsible for parasitism especially in humans, dogs, and cats. Parasites are the only ones that have a life cycle that involve free living form and parasitic. In this case, it was not possible to determine the primary portal of entry for the infection, but most infections commonly occur through the penetration of the larvae into the skin or mucous membranes, where they migrate via the haematogenous to the lung, then they are swallowed up to the intestine. Occasionally, there is autoinfection by larvae that enter the intestinal mucosa or perianal region and the contamination of neonates and puppies through the ingestion of milk. The clinical signs evidenced in this case, revealed the committed respiratory and gastrointestinal, possibly may be related to the migration of the larvae in the lungs and the destruction of the intestinal epithelium caused by the high number of parasites, respectively. It is concluded that strongyloidiasis is an uncommon infectious disease in puppies in Brazil, capable of causing severe respiratory and gastrointestinal changes that result in the death of animals with a high parasitic load and should be included in the differential diagnosis of diseases that affect the respiratory system and gastrointestinal tract of dogs.Keywords: dog disease, parasitic infection, nematode, Strongyloides stercoralis

Systemic Phaeohyphomycosis in a Dog Caused by Cladophialophora bantiana

Background: Cladophialophora bantiana is a dematiaceous fungus that causes phaeohyphomycosis, a generic term used to describe a variety of unusual mycoses caused by fungi that have melanin in their cell wall. C. bantiana targets the central nervous system, commonly causing localized brain infections that may result in disseminated infections. In Brazil, minimal phaeohyphomycosis data are available, and information about C. bantiana infections in animals, especially canines, is scarce. Thus, the aim of this study was to describe the clinical and pathological aspects of systemic phaeohyphomycosis caused by C. bantiana in a dog.Case: A 1-year-old female Pit Bull presented with weight loss, reduced appetite, and a history of cutaneous lesions on the right thoracic limb; however, clinical evolution was not reported. The dog had reportedly given birth recently. Physical examination revealed thinness, pale ocular and oral mucosa, submandibular lymph nodes, and enlarged popliteal lymph nodes. The animal died after convulsive crises during hospitalization. At necropsy, white-yellowish multifocal nodules were observed in the liver and right kidney. The brain featured left cerebral hemisphere asymmetry with blood vessel congestion in the leptomeninges and an irregular brownish focal area on the surface of the right occipital cortex. Cross-sections of the formalin-fixed brain exhibited compression of the left lateral ventricle and the presence of grayish and friable multifocal areas in the gray matter of the left parietal and right occipital cortices. Fragments of the lesions were collected for histopathological and microbiological examination. Histologically, the lesions were similar, characterized by hepatitis, nephritis, and granulomatous and necrotizing meningoencephalitis, multifocal to coalescing, accentuated, chronic, and associated with numerous pigmented fungi. Fontana-Masson–stained fungi exhibited a strong black color. In cleared and unstained histological slides, brownish pigmentation was observed in the cytoplasm and walls of the fungi. C. bantiana was identified via microbiological cultivation.Discussion: A diagnosis of phaeohyphomycosis caused by C. bantiana was made based on the characteristic morphology of the microscopic lesions and confirmed via isolation in microbiological culture. As numerous species cause phaeohyphomycosis, specific confirmation of the etiologic agent using several diagnostic techniques is necessary. In histopathological examinations, pigmented fungal organisms are easily seen among lesions. However, in some cases, the pigment is not apparent in the tissues. FM staining is necessary to demonstrate the presence of the melanin in fungi. As in most phaeohyphomycosis cases, it was not possible to determine the primary portal of entry. However, the lesion on the right thoracic limb probably favored the penetration of the agent. In addition to cerebral lesions, severe lesions in the hepatic and renal parenchyma were observed, which are characteristic of systemic mycosis. Infection and clinical diseases are usually associated with immunocompromised; here, the gestation period may have had an immunosuppressive effect, favoring the proliferation and dissemination of the agent. It was concluded that phaeohyphomycosis caused by C. bantiana produced severe systemic lesions in the brain and organs of the abdominal cavity. Although uncommon, phaeohyphomycosis caused by Cladophialophora bantiana should be included as a differential diagnosis for other canine diseases that present with similar clinical symptoms.Keywords: canine, fungal diseases, dematiaceous fungi, Cladosporium trichoides, Xylohypha bantiana, melanin, Fontana-Masso

RINOTRAQUEÍTE COM ENVOLVIMENTO DE PULMÃO E FÍGADO EM UM FELINO

O Herpes Vírus Felino tipo 1 é o principal agente causador do Complexo Respiratório Felino e causa infecção do trato respiratório superior. O objetivo desse trabalho foi relatar um caso de rinotraqueíte felina com envolvimento pulmonar e hepático. Um felino, sem raça definida, cinco meses, macho apresentou histórico de anorexia, secreção ocular e nasal seromucosa e espirros e morreu após o atendimento. Na necropsia observou-se cavidade nasal difusamente avermelhada, pulmões não colapsados e discretamente avermelhados. Microscopicamente, havia necrose do epitélio da cavidade nasal, dos pulmões e dos hepatócitos associada a inclusões anfofílicas intranucleares. O acometimento pulmonar e hepático por esse vírus é incomum e a histopatologia foi essencial para elucidação diagnóstica

COLANGIOCARCINOMA METASTÁTICO EM UM CÃO

Colangiocarcinoma é um neoplasma maligno oriundo do epitélio de ductos biliares comum em animais de companhia. Descreve-se um caso de colangiocarcinoma em um cão diagnosticado no Hospital Veterinário Universitário da Universidade Federal de Campina Grande, Patos, Paraíba. A cadela de seis anos de idade apresentou discreta icterícia e foi positiva no teste rápido para leishmaniose. O animal foi entanasiado e na necropsia observou-se fígado aumentado de volume com múltiplos nódulos branco-amarelados que se aprofundavam ao parênquima. Baço e linfonodos aumentados de tamanho com nódulos semelhantes aos descritos no fígado. Pulmões não colapsados com múltiplos nódulos brancacentos. Microscopicamente os nódulos observados no fígado, baço, linfonodos e pulmões eram compostos por células neoplásicas com origem de ductos biliares, caracterizando um quadro de colangiocarcinoma com metástase para órgãos da cavidade abdominal e torácica. O colangiocarcinoma metastático deve ser considerado em cães com insuficiência hepática associada à massas no parênquima hepático e em outros órgãos

POLIARTRITE, HEPATITE E BRONCOPNEUMONIA ABSCEDATIVA SECUNDÁRIAS A ONFALOFLEBITE EM UMA BEZERRA

Descreve-se um caso de onfaloflebite em uma bezerra de cinquenta dias de idade atendida na Clínica Médica e Cirúrgica de Grandes Animais. O animal apresentava sinais clínicos de diarreia e onfalite. Foi instituída terapia antimicrobiana e anti-inflamatória, além de correção da desidratação, porém o animal não apresentou melhora e foi a óbito, sendo posteriormente encaminhado ao Laboratório de Patologia Animal para realização de necropsia. Na necropsia foram observadas lesões absedativas no parênquima pulmonar, hepático e artrite séptica. O exame histopatológico revelou múltiplos abscessos no pulmão e fígado, com centro necrótico e miríades de agregados bacterianos circunscritos por acentuado infiltrado inflamatório neutrofílico e confirmando o quadro de septicemia, em consequência da onfaloflebite.  O diagnóstico foi realizado através de coleta de dados epidemiológicos, clínicos e patológicos

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.

CARCINOMA CRIBRIFORME METASTÁTICO EM UMA GATA

As neoplasias mamárias em gatas representam até 40% dos tumores encontrados nessa espécie, sendo o terceiro tipo mais incidente, seguido das neoplasias hematopoiéticas e cutâneas. Existem vários estudos sobre neoplasias de mama em cadelas, entretanto há poucos estudos relacionados a neoplasmas de mama em gatas, apesar da incidência do tumor mamário na espécie felina ser inferior a metade da incidência na espécie canina, a percentagem de neoplasias malignas é muito superior. O objetivo desse trabalho é descrever um caso de carcinoma cribriforme metastático em uma gata sem raça definida, com 10 anos de idade, que foi encaminhada para atendimento apresentando nódulos ulcerados na região das mamas inguinais há mais de seis meses. O diagnóstico de carcinoma cribiforme foi estabelecido com base nos achados anatomopatológicos

ESPOROTRICOSE LINFOCUTÂNEA EM GATO ERRANTE

A esporotricose é uma micose causada pelo fungo dimórfico Sporothrix schenckii, que possui capacidade de infectar o ser humano e os animais. Os gatos não castrados e com livre acesso à rua possuem um importante papel epidemiológico na transmissão e propagação da doença. A transmissão do agente ocorre principalmente pelo contato com o solo ou mordeduras e arranhaduras causadas pelos gatos. Os animais comumente apresentam nódulos ulcerados nos membros, região cervical, cefálica, face, pinas e cauda. Portanto, objetiva-se com este trabalho descrever um caso de esporotricose linfocutânea em um gato errante no Sertão da Paraíba. Foi encaminhado a uma clínica veterinária particular em Patos, Paraíba, um gato macho, adulto, sem raça definida, errante, apresentando lesões cutâneas ulceradas e multifocais por todo o corpo. Realizou-se citologia das lesões e identificaram-se miríades de leveduras fúngicas, morfologicamente compatíveis com Sporotrix sp. Devido ao mau prognóstico e dificuldade de realizar o tratamento, foi conduzida a eutanásia do animal. Na necropsia observavam-se lesões cutâneas ulceradas, avermelhadas, bem circunscritas e com bordos elevados e acinzentados, localizadas na face, pálpebra, orelha e membros, principalmente nas falanges e dígitos. No exame histopatológico da pele, observava-se a derme piogranulomatosa associada a estruturas fúngicas leveduriformes, variando de redondos a ovalados, com núcleo centralizado levemente basofilico, circundado por halo claro, e medindo 4-9µm de diâmetro compatíveis com Sporotrix sp. O diagnóstico foi estabelecido com base nos achados epidemiológicos, clínicos, citológicos e anatomopatológicos. É uma doença de alto potencial zoonótico e que requer medidas profiláticas efetivas para seu controle. A esporotricose é uma doença infecciosa relativamente frequente em gatos, que pode cursar com quadros clínico-patológicos graves, e usualmente demanda um prolongado e dispendioso tratamento antifúngico

Systemic Phaeohyphomycosis in a Dog Caused by Cladophialophora bantiana

Background: Cladophialophora bantiana is a dematiaceous fungus that causes phaeohyphomycosis, a generic term used to describe a variety of unusual mycoses caused by fungi that have melanin in their cell wall. C. bantiana targets the central nervous system, commonly causing localized brain infections that may result in disseminated infections. In Brazil, minimal phaeohyphomycosis data are available, and information about C. bantiana infections in animals, especially canines, is scarce. Thus, the aim of this study was to describe the clinical and pathological aspects of systemic phaeohyphomycosis caused by C. bantiana in a dog.Case: A 1-year-old female Pit Bull presented with weight loss, reduced appetite, and a history of cutaneous lesions on the right thoracic limb; however, clinical evolution was not reported. The dog had reportedly given birth recently. Physical examination revealed thinness, pale ocular and oral mucosa, submandibular lymph nodes, and enlarged popliteal lymph nodes. The animal died after convulsive crises during hospitalization. At necropsy, white-yellowish multifocal nodules were observed in the liver and right kidney. The brain featured left cerebral hemisphere asymmetry with blood vessel congestion in the leptomeninges and an irregular brownish focal area on the surface of the right occipital cortex. Cross-sections of the formalin-fixed brain exhibited compression of the left lateral ventricle and the presence of grayish and friable multifocal areas in the gray matter of the left parietal and right occipital cortices. Fragments of the lesions were collected for histopathological and microbiological examination. Histologically, the lesions were similar, characterized by hepatitis, nephritis, and granulomatous and necrotizing meningoencephalitis, multifocal to coalescing, accentuated, chronic, and associated with numerous pigmented fungi. Fontana-Masson–stained fungi exhibited a strong black color. In cleared and unstained histological slides, brownish pigmentation was observed in the cytoplasm and walls of the fungi. C. bantiana was identified via microbiological cultivation.Discussion: A diagnosis of phaeohyphomycosis caused by C. bantiana was made based on the characteristic morphology of the microscopic lesions and confirmed via isolation in microbiological culture. As numerous species cause phaeohyphomycosis, specific confirmation of the etiologic agent using several diagnostic techniques is necessary. In histopathological examinations, pigmented fungal organisms are easily seen among lesions. However, in some cases, the pigment is not apparent in the tissues. FM staining is necessary to demonstrate the presence of the melanin in fungi. As in most phaeohyphomycosis cases, it was not possible to determine the primary portal of entry. However, the lesion on the right thoracic limb probably favored the penetration of the agent. In addition to cerebral lesions, severe lesions in the hepatic and renal parenchyma were observed, which are characteristic of systemic mycosis. Infection and clinical diseases are usually associated with immunocompromised; here, the gestation period may have had an immunosuppressive effect, favoring the proliferation and dissemination of the agent. It was concluded that phaeohyphomycosis caused by C. bantiana produced severe systemic lesions in the brain and organs of the abdominal cavity. Although uncommon, phaeohyphomycosis caused by Cladophialophora bantiana should be included as a differential diagnosis for other canine diseases that present with similar clinical symptoms.Keywords: canine, fungal diseases, dematiaceous fungi, Cladosporium trichoides, Xylohypha bantiana, melanin, Fontana-Masso