Concomitant occurrence of multicentric hemangiosarcoma and histiocytic sarcoma in a dog

Histiocytic sarcoma (HS) is uncommon malignant neoplasia of round cells with marked predilection in Rottweiler and Bernese Mountain. The disseminated form, which mainly affects the spleen, lungs, lymph nodes, bone marrow, skin, and subcutis, presents a quick and aggressive clinical behavior. Hemangiosarcoma (HAS) is a malignant neoplasm of endothelial vessel cells commonly reported to affect the right atrium of dogs' hearts. A male Rottweiler, five years old, presented flaccid paraplegia and progressive muscular atrophy in the temporal, masseter, and limbs muscles; Due to the clinical stage of the animal, euthanasia was conducted. During the necroscopic examination, it was noticed that several masses presented different sizes; some were whitish, and others were reddish and spread in multiple organs (lungs, heart, spleen, stomach, kidneys, brain, medulla, skeletal muscle, and pre-scapular lymph node). Microscopically, in some organs such as the stomach, right ventricle, lungs, and medulla, it was noticed a proliferation of myeloid cells, highly cellular, with poor demarcation, no encapsulation, and with the infiltrative growth pattern of cells with high pleomorphism. Numerous tumoral emboli were observed in the spleen, brain, skeletal muscle, and lymph node. These cells were submitted for immunohistochemistry and were positive for CD18 (HS antibody). In the right atrium, liver, and kidney it was observed malignant and infiltrative endothelial proliferation (HSA) and emboli in the medulla. Therefore, we conclude that both neoplasms (HS and HSA) cause the animal's paraplegia due to their embolism and metastasis to the spinal cord and skeletal muscle.(AU)

Outbreak of leishmaniasis caused by Leishmania enriettii in guinea pigs (Cavia porcellus) / Surto de leishmaniose causada por Leishmania enriettii em cobaias (Cavia porcellus)

We describe an outbreak of leishmaniasis in seven guinea pigs (Cavia porcellus) in which nodular ulcerated skin lesions of varying sizes were observed in the nasal cavity, upper lip, pinnae, vulva, and periarticular region of the limbs. Cytologic exam of collected samples of the lesions in the auricle of one of the animals revealed macrophages containing parasitophorous vacuoles of approximately 4.0μm in diameter in their cytoplasm with morphology suggestive of Leishmania sp. Although skin lesions spontaneously regressed in two of the Guinea pigs, only one survived. All six animals that died were necropsied. Grossly, all animals showed bloody nodular cutaneous lesions with crusts. One of the guinea pigs had distended dark red and firm lungs. Histopathology of the skin lesions revealed histiocytic interstitial acanthotic dermatitis associated with a myriad of Leishmania organisms within macrophages cytoplasm. In the lung, the lesions were characteristic of broncho-interstitial pneumonia with focal infiltrates of neutrophils, epithelioid macrophages, and multinucleated giant cells containing 2µm basophilic amastigotes with morphology compatible with Leishmania spp. A focal granulomatous lesion ,associated with the causal agent in the lung is a novel description of leishmaniasis in guinea pigs caused by L. enriettii. The polymerase chain reaction (PCR) technique with mini-exon primer performed in samples of lesions from two affected guinea pigs was positive and equal to the reference strain, identifying Leishmania enriettii. The cytological, macroscopic, and histological lesions associated with the PCR technique allowed the diagnosis of leishmaniasis and the identification of the specie L. enriettii.

Descrevemos um surto de leishmaniose em sete cobaias (Cavia porcellus), com lesões cutâneas nodulares ulceradas de tamanhos variados observadas na cavidade nasal, lábio superior, pavilhões auriculares, vulva e região periarticular dos membros. No exame citológico foram encontrados macrófagos contendo vacúolos parasitóforos no citoplasma de aproximadamente 4.0μm em diâmetro com morfologia sugestiva de Leishmania sp. Apesar de regressão espontânea das lesões cutâneas terem ocorrido em duas das sete cobaias, apenas um sobreviveu. Seis dos sete animais afetados morreram e foram necropsiados. Macroscopicamente, todos os animais apresentaram lesões cutâneas nodulares, crostosas e sanguinolentas. Uma das cobaias tinha pulmões vermelho-escuros, distendidos e firmes. A histopatologia das lesões cutâneas revelou dermatite acantótica intersticial histiocítica associada a miríades de organismos de Leishmania no citoplasma de macrófagos. Nos pulmões as lesões eram características de pneumonia bronco-intersticial com infiltrado focal de neutrófilos, eosinófilos, macrófagos epitelioides e células gigantes multinucleadas contendo amastigotas basofílicos de 2µm com morfologia compatível com Leishmania spp. Lesões granulomatosas focais associadas ao agente no pulmão são um achado inédito na leishmaniose causada por L. enriettii em cobaias. A técnica de reação em cadeia da polimerase (PCR) com primer mini-exon realizada em amostras de lesões de duas cobaias afetadas foi positiva, identificando Leishmania enriettii. Os aspectos macroscópicos, citológicos, e histológicos associados à técnica da (PCR), permitiram o diagnóstico da leishmaniose e a identificação da espécie L. enriettii.

Linfoma extranodal de células B em vesícula urinária de um cão / Extranodal B-cell lymphoma in the urinary bladder in a dog

O linfoma é uma neoplasia de alta recorrência na rotina oncológica de medicina veterinária. Pode ser classificado em linfoma Hodgking-liked, com raros casos descritos somente em felinos,e não Hodgking, sendo este segundo o mais comum, subdividido em linfomas B ou T. O objetivo deste trabalho foi relatar a conduta clínica, diagnóstica e terapêutica do caso de uma cadela, de 12 anos, sem raça definida, que manifestava disúria, prostração, dor abdominal e ao exame físico a presença de uma massa na região hipogástrica. Esta foi diagnosticada com linfoma de grandes células por meio de exames de citologia e biópsia, com solicitação do exame de imunoistoquímica que confirmou linfoma difuso de grandes células de imunofenótipo B. Sem o envolvimento de nenhum outro sistema, classificou-se como linfoma primário de bexiga extranodal. O animal passou pelo tratamento quimioterápico realizando nove sessões de quimioterapia pelo protocolo de CHOP, contudo devido ao agravamento do caso a paciente veio a óbito cerca de sete meses após o diagnóstico da doença. O caso estudado foi de extrema importância para a compreensão de linfomas primários de bexiga em razão da escassez de informações relacionadas na literatura. Ainda, o cão é um excelente modelo experimental de linfomas não Hodgking em humanos, consequentemente compreender essa doença em cães promove a evolução conjunta da medicina humana.

Lymphoma is a highly recurrent rate neoplasm in the oncology routine of veterinary medicine. It can be classified into Hodgking-like, rarely described just in felines, and non-Hodgking lymphoma, the latter being the most commun, subdivided into B-cell lymphoma and T-cell lymphoma. The objective of this study was to report the clinical and therapeutic conduct within the diagnosis procedures of a 12-years-old female dog, mixed breed, who manifested dysuria, prostation, abdominal pain and on the physical examination a mass in the hypogastric region was noticed. This was diagnosed as a large cell lymphoma by means cytology and biopsy, also immunohistochemistry was required which confirmed the diffuse large cell lymphoma of immunophenotyping B. Without any other sistem envolved, the neoplasm was classified as primary urinary bladder lymphoma extranodal. The animal underwent chemotherapy, performing nine sessions according to the Madison protocol, however, due to the worsening of the case, the patient died about seven months after the diagnosis of the disease. This case was extremely importante for the understanding of primary urinary bladder lymphomas due to the scarcity of informations in the literature. Also, dog is an excellent experi,emtal model of non Hodgking lymphomas in humans, thus understandig this disease in dogs promotes the joint evolution of human medicine.

Linfoma difuso de grandes células em um buldogue inglês de dois anos: relato de caso / Diffuse large-cell lymphoma in a two-year-old english bulldog: case report

O linfoma é a neoplasia hematopoiética mais frequentemente diagnosticada na clínica de pequenos animais, sendo caracterizado por uma proliferação descontrolada de linfócitos, acometendo principalmente animais idosos. Dentre os achados clínicos mais comuns da doença, a linfadenopatia periférica recebe destaque. Manifestações clínicas como perda de peso, anorexia, edema subcutâneo, êmese, massas cutâneas, disfagia, ascite e dispnéia são também frequentemente encontradas. O diagnóstico dos linfomas é de extrema importância, sendo primordial para estabelecimento do prognóstico do animal, podendo ser feito através da análise citomorfológica de amostras obtidas por punção aspirativa e avaliação histopatológica. A poliquimioterapia é realizada como protocolo terapêutico de eleição para animais com linfoma. Foi atendido no Serviço de Clínica e Cirurgia Oncológica do Hospital Veterinário da Universidade Federal de Uberlândia (HV-UFU), um Buldogue Inglês, de dois anos de idade, apresentando linfonodonomegalia generalizada e diagnosticado com linfoma difuso de grandes células. O diagnóstico foi obtido por exame histopatológico e o imunohistoquímico revelou imunofenotipagem B. O paciente foi submetido a quimioterapia, sendo escolhido o protocolo Winscosin (CHOP) de 19 semanas com remissão completa ao término do protocolo. O objetivo deste trabalho é relatar um caso de linfoma difuso de grandes células em um Buldogue Inglês de dois anos de idade com remissão completa após a realização de quimioterapia.

Lymphoma is the hematopoietic neoplasm most frequently diagnosed in the clinic of small animals, being characterized by an uncontrolled proliferation of lymphocytes, affecting mainly elderly animals. Among the most common clinical findings of the disease, peripheral lymphadenopathy is highlighted. Clinical manifestations such as weight loss, anorexia, subcutaneous edema, emesis, skin masses, dysphagia, ascites and dyspnea are also frequently encountered. The diagnosis of lymphomas is extremely important, being essential for establishing the animal's prognosis and can be done through cytomorphological analysis of samples obtained by aspiration puncture and histopathological evaluation. Polychemotherapy is performed as the therapeutic protocol of choice for animals with lymphoma. It was treated at Serviço de Clínica e Cirurgia Oncológica do Hospital Veterinário da Universidade Federal de Uberlândia (HV-UFU), a two-year-old English Bulldog, with generalized lymph node enlargement and diagnosed with diffuse large cell lymphoma. The diagnosis was obtained by histopathological and immunohistochemical examination and revealed immunophenotyping B. The patient underwent chemotherapy, and the 19- week Winscosin (CHOP) protocol was chosen with complete remission at the end of the protocol. The aim of this work is to report a case of diffuse large cell lymphoma in a two-year-old English Bulldog with complete remission after chemotherapy.

Linfoma difuso de grandes células em um buldogue inglês de dois anos: relato de caso / Diffuse large-cell lymphoma in a two-year-old english bulldog: case report

O linfoma é a neoplasia hematopoiética mais frequentemente diagnosticada na clínica de pequenos animais, sendo caracterizado por uma proliferação descontrolada de linfócitos, acometendo principalmente animais idosos. Dentre os achados clínicos mais comuns da doença, a linfadenopatia periférica recebe destaque. Manifestações clínicas como perda de peso, anorexia, edema subcutâneo, êmese, massas cutâneas, disfagia, ascite e dispnéia são também frequentemente encontradas. O diagnóstico dos linfomas é de extrema importância, sendo primordial para estabelecimento do prognóstico do animal, podendo ser feito através da análise citomorfológica de amostras obtidas por punção aspirativa e avaliação histopatológica. A poliquimioterapia é realizada como protocolo terapêutico de eleição para animais com linfoma. Foi atendido no Serviço de Clínica e Cirurgia Oncológica do Hospital Veterinário da Universidade Federal de Uberlândia (HV-UFU), um Buldogue Inglês, de dois anos de idade, apresentando linfonodonomegalia generalizada e diagnosticado com linfoma difuso de grandes células. O diagnóstico foi obtido por exame histopatológico e o imunohistoquímico revelou imunofenotipagem B. O paciente foi submetido a quimioterapia, sendo escolhido o protocolo Winscosin (CHOP) de 19 semanas com remissão completa ao término do protocolo. O objetivo deste trabalho é relatar um caso de linfoma difuso de grandes células em um Buldogue Inglês de dois anos de idade com remissão completa após a realização de quimioterapia.(AU)

Lymphoma is the hematopoietic neoplasm most frequently diagnosed in the clinic of small animals, being characterized by an uncontrolled proliferation of lymphocytes, affecting mainly elderly animals. Among the most common clinical findings of the disease, peripheral lymphadenopathy is highlighted. Clinical manifestations such as weight loss, anorexia, subcutaneous edema, emesis, skin masses, dysphagia, ascites and dyspnea are also frequently encountered. The diagnosis of lymphomas is extremely important, being essential for establishing the animal's prognosis and can be done through cytomorphological analysis of samples obtained by aspiration puncture and histopathological evaluation. Polychemotherapy is performed as the therapeutic protocol of choice for animals with lymphoma. It was treated at Serviço de Clínica e Cirurgia Oncológica do Hospital Veterinário da Universidade Federal de Uberlândia (HV-UFU), a two-year-old English Bulldog, with generalized lymph node enlargement and diagnosed with diffuse large cell lymphoma. The diagnosis was obtained by histopathological and immunohistochemical examination and revealed immunophenotyping B. The patient underwent chemotherapy, and the 19- week Winscosin (CHOP) protocol was chosen with complete remission at the end of the protocol. The aim of this work is to report a case of diffuse large cell lymphoma in a two-year-old English Bulldog with complete remission after chemotherapy.(AU)

Atypical spleen hemophagocytic histiocytic sarcoma in a dog

Background: The histiocytic sarcoma (HS) complex is a set of malignant neoplasms originating from interstitial dendritic cells or macrophages. When it involves macrophages of the splenic red pulp and bone marrow, it is referred to as hemophagocytic histiocytic sarcoma (HHS). HHS behaves more aggressively than HS and is usually fatal. HHS can be diagnosed by cytological and histopathological examination of neoplastic tissue. HHS is confirmed by immunohistochemistry using an anti-CD11d antibody. This neoplasm is often confused with immune-mediated hemolytic anemia or Evans syndrome due to erythrophagocytosis and platelet consumption. The clinical presentation of the animals progresses with evident anemia and thrombocytopenia, leading to signs such as prostration, inappetence, and pale mucosa, making diagnosis challenging and often late. This study aimed to report the clinic-pathological aspects of a canine with atypical hemophagocytic splenic HS. Case: A 4-year-old male Shih-Tzu canine was referred to the Veterinary Hospital with a history of prostration and anorexia. Pale mucous membranes were observed on physical examination. Blood tests revealed non-regenerative anemia, leukopenia, and thrombocytopenia. Serum protein levels were below the reference values for the species in biochemical examinations. Hemoparasitosis was suspected; however, the result of the polymerase chain reaction was negative. Abdominal ultrasound revealed a splenomegaly with heterogeneous parenchyma and a slightly irregular surface, but no visible mass in the spleen. Due to the difficulty of stabilizing the patient, even after successive transfusions, the animal underwent exploratory laparotomy with medial access and posterior splenectomy. Subsequently, the spleen was surgically removed, fixed in 10% buffered formalin, and processed routinely. Macroscopically, it had an irregular reddish-brown capsular surface. Histopathological examination of the spleen revealed a densely cellular neoplasm composed of round to spindle cells (histiocytes) arranged haphazardly in variably sized sheets separating the pre-existing spleen stroma. These histopathological findings were consistent with a histiocytic malignant neoplasm. Immunohistochemical analysis was performed to better define the origin of the histiocytic neoplasm. Neoplastic cells showed positive immunostaining of more than 80% of tumor cells for the CD11d antibody and weak immunostaining for CD11c and lysozyme. The patient survived for less than 30 days after the first hospital visit. Discussion: The diagnosis of HHS was based on the histological characteristics and positive immunostaining of more than 80% of the tumor cells for the CD11d antibody. HHS is an extremely aggressive and rare tumor that affects elderly dogs of any breed. In this study, HHS had atypical histologic characteristics, in which erythrophagocytosis and hemosiderin were not observed within macrophages. HHSs arise from macrophages of the red pulp of the spleen or bone marrow and express the b2 integrin, CD11d, and have low expression of CD1 and CD11c, which are predominantly expressed by non-hemophagocytic HS. The hematological and biochemical changes observed in this case were similar to those described in other dogs with HHS. Treatment of HHS is only palliative. Erlichia ewingii, E. canis, Anaplasma phagocytophilum, A. platys, Borrelia burgdorferi, Dirofilaria immitis, Leishmania infantum and immune-mediated hemolytic anemia are the main differential diagnoses because they cause anemia and thrombocytopenia accompanied by splenomegaly.

Eletrocardiografia computadorizada em cadelas com tumores mamários / Electrocardiography in bitches with mammary tumors

The incidence of cancer has increased due to greater longevity of the animals as a consequence of better control of other diseases, improvement of nutrition and good practices in preventive medicine. Malignant tumors can cause paraneoplastic syndrome such as hypercalcemia, anemia, cachexia, among others and consequent cardiovascular disorders. The electrocardiography (ECG) is a complementary exam that can reveal with its traces these rhythmic disorders. Based on that, the objective of this study was to evaluate the ECG in bitches with mammary tumors in order to detect in which type of tumor would be found significant changes as in cardiac rhythm, ECG waves, segments or cardiac axis. Twenty-nine female dogs were used in this study, being 19 bitches with mammary tumor, and they were allocated in three groups: G1: control group (n = 10), G2: benign neoplasia group (n = 6) and G3: malignant neoplasia group (n = 13). The most prevalent type of neoplasia in G2 was the benign mixed tumor (83%), followed by adenoma (17%) whereas in G3: carcinoma in mixed tumor (61%); papillary carcinoma (23%). Regarding cardiac rhythm, it was found sinus arrhythmia (SA) and normal sinus rhythm (NS): G1: 50% SA and 50% NS; G2: 67% SA and 33% NS; G3: 54% SA and 46% NS. No ventricular or atrial arrhythmias were detected. For other parameters in G1, G2 and G3, respectively (mean ± Std error): FC (bpm): 110±9.2, 120 ± 8.5, 124±7,5; P (ms): 48 ± 1.6, 51 ± 1.8, 50 ± 1.2; P (mV) 0.19 ± 0.02, 0.2 ± 0.02, 0.19 ± 0.02; PR (ms): 94 ± 4.3, 93 ± 5.5, 89 ± 3.9; QRS (ms): 56 ± 1.54, 60 ± 4, 62 ± 1.2; R (mV): 1.1 ± 0.06, 1.2 ± 0.24, 0.9 ± 0.13; QT (ms): 203 ± 9.4; 204 ± 7.9; 182 ± 15.6; and cardiac axis (°): 66 ± 6.2, 61 ± 7.9, 70 ± 7.5. There were no significant differences for all cardiac parameters and also for ST interval and T wave morphology. All electrocardiographic parameters found are in accordance with other studies carried out in the canine species. The results regarding tumor types differ from what was found in another study, in which in 18 bitches with mammary tumors, 55% were benign, with prevalence of adenomas (38%) followed by benign mixed tumors, and 45% malignant, with adenocarcinoma prevailing (22%). In another study, it was verified in 63 bitches the predominance of tubular carcinoma (26.56%) and carcinoma in mixed tumors (23.44%). Diverging from the electrocardiographic parameters of this study, a significant difference was found in the R wave amplitude value in the research by Barros et al., (2015) who performed computerized electrocardiography in 50 dogs, not only with mammary neoplasms (55% mammary carcinomas), but also in mastocytomas, lymphomas, benign tumors and other sarcomas. This author found out that the R wave amplitude values of the neoplasia group were lower when compared to the control group. In addition, we suspect that other types of tumors could result in more paraneoplastic syndrome than the mammary neoplasms found in this research. Neoplasms as lymphomas (T cells), apocrine gland anal sac adenocarcinomas, multiple myelomas and thymomas are known as a cause of hypercalcemia of malignancy and histiocytic sarcomas, myelomas, leukemia and lymphomas causing anemia. In conclusion, ECG has no changes in benign or malignant mammary tumors in dogs. However, this fact does not exclude the importance of its performance in pre-anesthetic evaluations. Further studies with a larger sample including the clinical staging of these bitches with a balanced number of animals with low and high staging are suggested.(AU)

Encefalitozoonose em coelho (Oryctolagus cuniculus) / Encephalitozoonosis in rabbit (Oryctolagus cuniculus)

Background: Encephalitozoonosis is caused by the protozoan Encephalitozoon cuniculi, in rabbits, and can affect humans. The disease can be fatal and difficult to diagnose. It can be asymptomatic or cause vestibular neurological disease, paralysis, uveitis in addition to chronic kidney disease in rabbits. The transmission of the microorganism's spores occurs by ingestion, inhalation, or by the transplacental route. The aim of this work is to report a case of encephalitozoonosis in a pet rabbit (Oryctolagus cuniculus). Case: An Oryctolagus cuniculus with a history of paraparesis of the thoracic and pelvic limbs was referred for necropsy, the evolution of the clinical picture happened in one day. After death, a necropsy was performed. Organ fragments were collected, fixed, and processed routinely for histology. Macroscopically, there was evidence of hepatic lobes, without injury to the other organs. Microscopically it was observed in the white and gray substance of the telencephalon multiple circumscribed granulomas composed of a necrotic center surrounded by macrophages, giant multinucleated cells in addition to lymphocytes and plasmocytes in the periphery, delimited by fibrous connective tissue. Around the vessels, perivascular cuffs with 2 to 4 layers of lymphocytic infiltrate were observed. Besides, special staining of Schiff's Periodic Acid (PAS) and Ziehl-Neelsen was performed, in which numerous cylindrical, eosinophilic structures of approximately 2.5 x 1.0 µm were observed, compatible with E. cuniculi spores. Besides, histiocytic lymphoblasts pericoronitis was noted in the liver. There were no relevant changes in the kidney. Discussion: The diagnosis of encephalitozoonosis in rabbits was based on clinical and anatomopathological findings. Tetraparesis was the predominant sign in the present case and was justified by telencephalic lesions. This clinical sign is included in the literature but is less common than the syndrome such as head tilt and paralysis. The diagnosis of the disease is usually made by post mortem examination when it is possible to identify the spores in the lesions. Multifocal granulomatous encephalitis was the most significant finding in this case, which is also consistent with other studies. The pathogenesis of granulomatous lesions is still controversial. It is known that spores allow phagocytosis by macrophages, which induce the production of interleukins and other cytokines by TCD4 + lymphocytes, thereby activating the action of TCD8 + (cytotoxic) lymphocytes. Natural killer cells, granulocytes, other macrophages, and B lymphocytes are also recruited. Although there is such an inflammatory response, the antibodies produced are not efficient to eliminate the agent from the host organism, however, they contribute to the process of opsonization and consequent phagocytosis, facilitating the destruction of the microsporidium by macrophages. The neurological form was predominant in this case, with no chronic or ocular renal forms, possibly due to the rapid clinical evolution. Special stains were useful for visualizing intralesional spores. Although PAS staining is considered to be of little use, it was relevant in this case. The visualization of the agent made it possible to distinguish differential diagnoses, among them vestibular syndrome secondary to otitis due to pasteurellosis, toxoplasmosis, neoplasms, traumas, or diseases of the spine. Thus, a diagnosis of encephalitozoonosis was made in a rabbit through clinical and anatomopathological correlation using Ziehl-Neelsen and PAS stains.

Hemophagocytic histiocytic sarcoma in dog

Background: Histiocytic sarcoma can present in a localized or disseminated form, being a malignant neoplasm derived from interstitial dendritic cells. Another form of the disease is called hemophagocytic histiocystic sarcoma (HHS), which originates from macrophages located in the splenic red pulp and bone marrow. HHS is a rare neoplasm with unknown etiology and rapid development. It mainly affects middle-aged to elderly animals. It primarily affects the spleen and bone marrow, with occurence of metastases in other organs. Some canine breeds are considered more predisposed to this neoplasia, among them the Rottweiler. The aim of this study was to report a case of HHS in a Rottweiler dog. Case: An 8-year-old Rottweiler suffering from hyporexia and progressive weight loss for a month was attended at the Veterinary Hospital of State University of Maringá. On physical examination, he only presented mild discomfort on abdominal palpation. Blood count was performed, which revealed mild thrombocytopenia (145,000/µL, reference value for the species 150,000-500,000/µL). The Polymerase Chain Reaction (PCR) exam was requested for babesiosis and ehrlichiosis, due to a history of ectoparasites. The animal was released with the prescription of Doxycycline at a dose of 10 mg/kg orally for 28 days. After 5 days, the condition worsened and the animal returned with emesis, apathy and hyporexia, being hospitalized. Abdominal ultrasound, blood count, urinalysis, serum urea and creatinine tests were requested. Among the hematological changes, thrombocytopenia (116,000/µL) and the appearing of regenerative anemia and atypical round cells with ample and slightly basophilic cytoplasm in the smear, similar to histiocytes, stood out. On ultrasound examination, splenomegaly was observed with hypoechogenic areas. Ultrasound-guided fine-needle aspiration cytology (FNAC) of the spleen was performed, which...

Hemophagocytic histiocytic sarcoma in dog

Background: Histiocytic sarcoma can present in a localized or disseminated form, being a malignant neoplasm derived from interstitial dendritic cells. Another form of the disease is called hemophagocytic histiocystic sarcoma (HHS), which originates from macrophages located in the splenic red pulp and bone marrow. HHS is a rare neoplasm with unknown etiology and rapid development. It mainly affects middle-aged to elderly animals. It primarily affects the spleen and bone marrow, with occurence of metastases in other organs. Some canine breeds are considered more predisposed to this neoplasia, among them the Rottweiler. The aim of this study was to report a case of HHS in a Rottweiler dog. Case: An 8-year-old Rottweiler suffering from hyporexia and progressive weight loss for a month was attended at the Veterinary Hospital of State University of Maringá. On physical examination, he only presented mild discomfort on abdominal palpation. Blood count was performed, which revealed mild thrombocytopenia (145,000/µL, reference value for the species 150,000-500,000/µL). The Polymerase Chain Reaction (PCR) exam was requested for babesiosis and ehrlichiosis, due to a history of ectoparasites. The animal was released with the prescription of Doxycycline at a dose of 10 mg/kg orally for 28 days. After 5 days, the condition worsened and the animal returned with emesis, apathy and hyporexia, being hospitalized. Abdominal ultrasound, blood count, urinalysis, serum urea and creatinine tests were requested. Among the hematological changes, thrombocytopenia (116,000/µL) and the appearing of regenerative anemia and atypical round cells with ample and slightly basophilic cytoplasm in the smear, similar to histiocytes, stood out. On ultrasound examination, splenomegaly was observed with hypoechogenic areas. Ultrasound-guided fine-needle aspiration cytology (FNAC) of the spleen was performed, which...(AU)

Histopathological and immunophenotypical characterization of canine multicentric lymphoma in Brazil: a study of 203 cases / Caracterização histopatológica e imunofenotípica do linfoma multicêntrico canino no Brasil: um estudo de 203 casos

The immunophenotype is regarded as an independent prognostic factor in high-grade lymphomas, seeing that lymphomas of T-cell origin are associated with shorter survival time. Although a number of studies have evaluated the immunophenotypical profile of lymphoma in the USA and Europe, Brazilian research on the matter remains scarce. Exact characterization of the histopathological type is crucial to establish proper treatment and prognosis. This study evaluated the database of immunohistochemistry laboratories that perform immunophenotyping of canine lymphoma in Brazil. A total of 203 cases of multicentric lymphoma were classified according to the WHO classification. Immunophenotyping was able to identify 71.4% lymphomas of B-cell line, 27.1% of T-cell line and 1.5% of non-B cells and non-T cell lines. Diffuse large B-cell lymphoma was the most common with 59.1% of the cases. Among T-cell lymphomas, lymphoblastic was the most common (11.33% of the cases). Even though canine lymphomas tend to be high-grade, indolent lymphomas comprised 11.82% of the cases and T-zone lymphoma was the most prevalent (8.86%). The immunophenotype of multicentric lymphoma in Brazil is similar to those in other parts of the world, which suggests similar etiologic factors to the development of this disease.(AU)

O imunofenótipo é considerado um fator prognóstico independente em linfomas de alto grau, visto que os linfomas de origem de células T estão associados a menor tempo de sobrevida. Apesar de vários estudos terem avaliado o perfil imunofenotípico do linfoma nos EUA e na Europa, a pesquisa brasileira sobre o assunto ainda é escassa. A caracterização exata do tipo histopatológico é crucial para estabelecer o tratamento e o prognóstico adequados. Este estudo avaliou a base de dados de laboratórios de imuno-histoquímica que realizam imunofenotipagem do linfoma canino no Brasil. Um total de 203 casos de linfoma multicêntrico foi classificado de acordo com a classificação da OMS. A imunofenotipagem foi capaz de identificar 71,4% dos linfomas da linhagem de células B, 27,1% da linhagem de células T e 1,5% das linhagens de células não B e não T. O linfoma difuso de grandes células B foi o mais comum em 59,1% dos casos. Entre os linfomas de células T, o linfoblástico foi o mais comum (11, 33% dos casos). Embora os linfomas caninos tendam a ser de alto grau, os linfomas indolentes representaram 11,82% dos casos e o linfoma da zona T foi o mais prevalente (8,86%). O imunofenótipo do linfoma multicêntrico no Brasil é semelhante ao de outras partes do mundo, o que sugere fatores etiológicos semelhantes ao desenvolvimento dessa doença.(AU)

Histopathological and immunophenotypical characterization of canine multicentric lymphoma in Brazil: a study of 203 cases / Caracterização histopatológica e imunofenotípica do linfoma multicêntrico canino no Brasil: um estudo de 203 casos

The immunophenotype is regarded as an independent prognostic factor in high-grade lymphomas, seeing that lymphomas of T-cell origin are associated with shorter survival time. Although a number of studies have evaluated the immunophenotypical profile of lymphoma in the USA and Europe, Brazilian research on the matter remains scarce. Exact characterization of the histopathological type is crucial to establish proper treatment and prognosis. This study evaluated the database of immunohistochemistry laboratories that perform immunophenotyping of canine lymphoma in Brazil. A total of 203 cases of multicentric lymphoma were classified according to the WHO classification. Immunophenotyping was able to identify 71.4% lymphomas of B-cell line, 27.1% of T-cell line and 1.5% of non-B cells and non-T cell lines. Diffuse large B-cell lymphoma was the most common with 59.1% of the cases. Among T-cell lymphomas, lymphoblastic was the most common (11.33% of the cases). Even though canine lymphomas tend to be high-grade, indolent lymphomas comprised 11.82% of the cases and T-zone lymphoma was the most prevalent (8.86%). The immunophenotype of multicentric lymphoma in Brazil is similar to those in other parts of the world, which suggests similar etiologic factors to the development of this disease.(AU)

O imunofenótipo é considerado um fator prognóstico independente em linfomas de alto grau, visto que os linfomas de origem de células T estão associados a menor tempo de sobrevida. Apesar de vários estudos terem avaliado o perfil imunofenotípico do linfoma nos EUA e na Europa, a pesquisa brasileira sobre o assunto ainda é escassa. A caracterização exata do tipo histopatológico é crucial para estabelecer o tratamento e o prognóstico adequados. Este estudo avaliou a base de dados de laboratórios de imuno-histoquímica que realizam imunofenotipagem do linfoma canino no Brasil. Um total de 203 casos de linfoma multicêntrico foi classificado de acordo com a classificação da OMS. A imunofenotipagem foi capaz de identificar 71,4% dos linfomas da linhagem de células B, 27,1% da linhagem de células T e 1,5% das linhagens de células não B e não T. O linfoma difuso de grandes células B foi o mais comum em 59,1% dos casos. Entre os linfomas de células T, o linfoblástico foi o mais comum (11, 33% dos casos). Embora os linfomas caninos tendam a ser de alto grau, os linfomas indolentes representaram 11,82% dos casos e o linfoma da zona T foi o mais prevalente (8,86%). O imunofenótipo do linfoma multicêntrico no Brasil é semelhante ao de outras partes do mundo, o que sugere fatores etiológicos semelhantes ao desenvolvimento dessa doença.(AU)

Progressive histiocytosis of non-epitheliotropic dendritic cells in a feline

Background: Histiocytic tumors in felines are nodules that commonly develop on limbs and head extremities. They can be divided into many subtypes including cutaneous histiocytoma, histiocytic sarcoma, reactive fibrohistiocytic nodule, Langerhans cell histiocytosis, and progressive feline dendritic cell. Despite the same origin, they have behaviors that differ from each other, thus it is important to confirm diagnosis with histopathological and immunohistochemical tests, because early identification can facilitate prognosis and treatment. In this study, we describe the pathological and immunohistochemical characteristics, enabling differentiation feline neoplasms derived from histiocytes. Case: A 5-year-old, crossbreed, male, feline presented with a nodulation at the base of the left ear. The mass was slow growing, partially alopecic, with no other changes associated with tumor development. The nodule was round and circumscribed, movable, with an elevated surface. He was referred for surgery and an elliptical sample around the tumor was carefully dissected. Routine histopathological evaluation was performed with hematoxylin and eosin (HE), as well as immunohistochemistry. Histopathology showed circumscribed proliferation of histiocytic cells, with abundant and eosinophilic cytoplasm. The proliferative cells were large and rounded, extending from the superficial dermis and basement membrane to the deep dermis. At the extremities, some cells had visible vacuoles. Mitotic activity ranged from 3 to 4 mitoses per field in 40x magnification. Immunohistochemistry showed positive staining for histocompatibility complex MCII and lysozyme antibodies, marking histiocytic cells. Labeling was positive for CD20 in cells of lymphoid lineage B and negative for E-cadherin. Histiocytic cells did not invade the epidermis; hence, proliferation was classified as nonepitheliotropic. These methods contribute to the literature regarding the...

Progressive histiocytosis of non-epitheliotropic dendritic cells in a feline

Background: Histiocytic tumors in felines are nodules that commonly develop on limbs and head extremities. They can be divided into many subtypes including cutaneous histiocytoma, histiocytic sarcoma, reactive fibrohistiocytic nodule, Langerhans cell histiocytosis, and progressive feline dendritic cell. Despite the same origin, they have behaviors that differ from each other, thus it is important to confirm diagnosis with histopathological and immunohistochemical tests, because early identification can facilitate prognosis and treatment. In this study, we describe the pathological and immunohistochemical characteristics, enabling differentiation feline neoplasms derived from histiocytes. Case: A 5-year-old, crossbreed, male, feline presented with a nodulation at the base of the left ear. The mass was slow growing, partially alopecic, with no other changes associated with tumor development. The nodule was round and circumscribed, movable, with an elevated surface. He was referred for surgery and an elliptical sample around the tumor was carefully dissected. Routine histopathological evaluation was performed with hematoxylin and eosin (HE), as well as immunohistochemistry. Histopathology showed circumscribed proliferation of histiocytic cells, with abundant and eosinophilic cytoplasm. The proliferative cells were large and rounded, extending from the superficial dermis and basement membrane to the deep dermis. At the extremities, some cells had visible vacuoles. Mitotic activity ranged from 3 to 4 mitoses per field in 40x magnification. Immunohistochemistry showed positive staining for histocompatibility complex MCII and lysozyme antibodies, marking histiocytic cells. Labeling was positive for CD20 in cells of lymphoid lineage B and negative for E-cadherin. Histiocytic cells did not invade the epidermis; hence, proliferation was classified as nonepitheliotropic. These methods contribute to the literature regarding the...(AU)

Disseminated histiocytic sarcoma in a Labrador retriever in Brazil

Histiocytic sarcoma (HS) refers to a rare neoplasm of round cells frequently presented in a disseminated form, affecting bones, joints, skin, and subcutaneous tissue. The objective of this study was to report a case of disseminated HS in a canine attended at HOVET-UFRPE, Recife, Brazil. Physical examination and complementary tests were performed; complete blood count and serum biochemistry were normal, but at thoracic radiography exam a neoformation was detected in the right lung. Cytopathological evaluation was suggestive of malignant epithelial neoplasia. At necropsy, there were disseminated nodules in the lungs, liver, spleen, kidneys, meninges and eye. The histopathological examination revealed proliferation of pleomorphic round cells, suggesting HS, which was confirmed by immunohistochemistry. From the obtained results, it becomes evident the importance of complementary exams to properly diagnose histiocytic diseases. This is one of the few reports of canine disseminated HS in Brazil.

Disseminated histiocytic sarcoma in a Labrador retriever in Brazil

Histiocytic sarcoma (HS) refers to a rare neoplasm of round cells frequently presented in a disseminated form, affecting bones, joints, skin, and subcutaneous tissue. The objective of this study was to report a case of disseminated HS in a canine attended at HOVET-UFRPE, Recife, Brazil. Physical examination and complementary tests were performed; complete blood count and serum biochemistry were normal, but at thoracic radiography exam a neoformation was detected in the right lung. Cytopathological evaluation was suggestive of malignant epithelial neoplasia. At necropsy, there were disseminated nodules in the lungs, liver, spleen, kidneys, meninges and eye. The histopathological examination revealed proliferation of pleomorphic round cells, suggesting HS, which was confirmed by immunohistochemistry. From the obtained results, it becomes evident the importance of complementary exams to properly diagnose histiocytic diseases. This is one of the few reports of canine disseminated HS in Brazil.(AU)

Aspectos epidemiológicos, clínicos e anatomopatológicos do linfoma folicular em cães / Epidemiological, clinical and pathological aspects of follicular lymphoma in dogs

Linfomas foliculares são uma rara forma de distúrbio linfoproliferativo descrita em medicina veterinária. Juntamente com a não reconhecida ocorrência dos linfomas de Hodgkin em cães, essa é a maior diferença acerca de linfoma entre humanos e cães. O objetivo deste artigo é descrever os achados epidemiológicos, clínicos e anatomopatológicos vistos em cinco cães com linfoma folicular. Destes, dois eram machos (40%) e três eram fêmeas (60%). A idade dos cães afetados variou de 11 a 13 anos. Quatro dos cinco (80%) cães eram de raça pura e um (20%) não tinha raça definida. Todos os cães apresentaram linfadenomegalia generalizada e esplenomegalia, o que incluiu os casos como linfoma multicêntrico. Na necropsia, os linfonodos e o baço demonstraram um padrão nodular à superfície de corte, caracterizado por dezenas a centenas de nódulos brancos, multifocais ou coalescentes e de tamanhos variáveis. Na superfície natural do baço, frequentemente (4/5, 80%), havia miríades de pontos brancos, multifocais ou coalescentes, de tamanhos variáveis. Na histopatologia, os tumores foram confirmados como linfomas foliculares. Todos os casos eram Grau III, sendo dois (40%) incluídos como IIIa e outros três (60%) como IIIb. Em um caso (1/5, 20%), o linfoma folicular foi considerado como IIIb variante de pequenos centroblastos semelhantes aos linfócitos neoplásicos vistos no linfoma de Burkitt. Os linfomas foram validados como tendo origem em células B através da imuno-histoquímica, utilizando anticorpos anti-CD20. Os casos de linfomas foliculares descritos comportaram-se de forma agressiva e levaram os pacientes à morte.(AU)

Follicular lymphomas are a rare form of lymphoproliferative disorder described in veterinary medicine. Together with the probable non-existence of Hodgkin's lymphomas in dogs, this is the biggest difference about lymphoma between humans and dogs. The aim of this article is to describe the epidemiological, clinical and anatomopathological findings observed in five dogs with follicular lymphoma. Of the five dogs with follicular lymphoma, two were male (40%) and three were female (60%). The age of affected dogs ranged from 11 to 13 years. Four of the five (80%) dogs were purebred and one (20%) had no defined breed. All dogs presented generalized lymphadenomegaly and splenomegaly, which included cases as multicentric lymphoma. At necropsy, the lymph nodes and the spleen demonstrated a nodular pattern at the cut surface, characterized by tens to hundreds of white nodules of variable size, multifocal or coalescing. On the natural surface of the spleen, often (4/5, 80%), there were myriads of white, multifocal or coalescing dots of varying sizes. In histopathology, the tumors were confirmed as follicular lymphomas. All cases were Grade III, two (40%) included as IIIa and three (60%) as IIIb. In one case (1/5, 20%), follicular lymphoma was considered as a IIIb variant of small centroblasts similar to the neoplastic lymphocytes seen in Burkitt's lymphoma. Lymphomas were validated as having origin in B cells through immunohistochemistry, using anti-CD20 antibody. The cases of follicular lymphomas described behaved aggressively and led the patients to death.(AU)

Aspectos epidemiológicos, clínicos e anatomopatológicos do linfoma folicular em cães / Epidemiological, clinical and pathological aspects of follicular lymphoma in dogs

Linfomas foliculares são uma rara forma de distúrbio linfoproliferativo descrita em medicina veterinária. Juntamente com a não reconhecida ocorrência dos linfomas de Hodgkin em cães, essa é a maior diferença acerca de linfoma entre humanos e cães. O objetivo deste artigo é descrever os achados epidemiológicos, clínicos e anatomopatológicos vistos em cinco cães com linfoma folicular. Destes, dois eram machos (40%) e três eram fêmeas (60%). A idade dos cães afetados variou de 11 a 13 anos. Quatro dos cinco (80%) cães eram de raça pura e um (20%) não tinha raça definida. Todos os cães apresentaram linfadenomegalia generalizada e esplenomegalia, o que incluiu os casos como linfoma multicêntrico. Na necropsia, os linfonodos e o baço demonstraram um padrão nodular à superfície de corte, caracterizado por dezenas a centenas de nódulos brancos, multifocais ou coalescentes e de tamanhos variáveis. Na superfície natural do baço, frequentemente (4/5, 80%), havia miríades de pontos brancos, multifocais ou coalescentes, de tamanhos variáveis. Na histopatologia, os tumores foram confirmados como linfomas foliculares. Todos os casos eram Grau III, sendo dois (40%) incluídos como IIIa e outros três (60%) como IIIb. Em um caso (1/5, 20%), o linfoma folicular foi considerado como IIIb variante de pequenos centroblastos semelhantes aos linfócitos neoplásicos vistos no linfoma de Burkitt. Os linfomas foram validados como tendo origem em células B através da imuno-histoquímica, utilizando anticorpos anti-CD20. Os casos de linfomas foliculares descritos comportaram-se de forma agressiva e levaram os pacientes à morte.(AU)

Follicular lymphomas are a rare form of lymphoproliferative disorder described in veterinary medicine. Together with the probable non-existence of Hodgkin's lymphomas in dogs, this is the biggest difference about lymphoma between humans and dogs. The aim of this article is to describe the epidemiological, clinical and anatomopathological findings observed in five dogs with follicular lymphoma. Of the five dogs with follicular lymphoma, two were male (40%) and three were female (60%). The age of affected dogs ranged from 11 to 13 years. Four of the five (80%) dogs were purebred and one (20%) had no defined breed. All dogs presented generalized lymphadenomegaly and splenomegaly, which included cases as multicentric lymphoma. At necropsy, the lymph nodes and the spleen demonstrated a nodular pattern at the cut surface, characterized by tens to hundreds of white nodules of variable size, multifocal or coalescing. On the natural surface of the spleen, often (4/5, 80%), there were myriads of white, multifocal or coalescing dots of varying sizes. In histopathology, the tumors were confirmed as follicular lymphomas. All cases were Grade III, two (40%) included as IIIa and three (60%) as IIIb. In one case (1/5, 20%), follicular lymphoma was considered as a IIIb variant of small centroblasts similar to the neoplastic lymphocytes seen in Burkitt's lymphoma. Lymphomas were validated as having origin in B cells through immunohistochemistry, using anti-CD20 antibody. The cases of follicular lymphomas described behaved aggressively and led the patients to death.(AU)

Infecção natural por Histomonas meleagridis em pavões-indianos (Pavo cristatus) / Histomonas meleagridis natural infection in peacocks (Pavo cristatus)

Background: Histomonas, also known as blackhead, is a protozoan disease caused by Histomonas meleagridis (phylum Parabasalia, class Tritrichomonadea, order Tritrichomonadida, family Dientamoebidae/Protrichomonadinae) and, characterized by enteric and hepatic lesions in several species of domestic and wild gallinaceous. Among the most affected species, turkeys are those with greater morbidity and mortality. Blackhead is the second most important disease caused by protozoa in domestic poultry, affecting especially young birds and causing severe economic losses, with decrease in production, lack of uniformity of lots and costs with treatment and control. Its occurrence must be monitored, especially in large poultry exporting countries, such as Brazil. The aim of this study is to report an outbreak of histomoniasis in Indian peacocks.Case: A peacocks group created together with chickens showed clinical signs characterized by apathy, head down and bruised head, eyes closed, anorexia, yellow or pale stools and death. At necropsy, the cecum showed intense thickening of the wall with irregularity in the serous layer and abundant deposit of friable material, amorphous, yellowish color with areas reddish in the lumen with large number of filiform white parasites from 1 to 1.5 cm in length, morphologically compatible with Heterakis gallinarum. The liver showed large and circular, multifocal, whitish areas that extended towards the parenchyma. Histologically, was observed marked transmural typhlitis, severe proliferation of fibroblasts with multifocal neovascularization, histiocytic infiltrate, giant cell enlargement, bacterial myriads, presence of eosinophilic circulars trophozoites, with 6-20 μm in diameter, morphologically compatible with Histomonas meleagridis. These structures were positive in PAS staining.[...]

Infecção natural por Histomonas meleagridis em pavões-indianos (Pavo cristatus) / Histomonas meleagridis natural infection in peacocks (Pavo cristatus)

Background: Histomonas, also known as blackhead, is a protozoan disease caused by Histomonas meleagridis (phylum Parabasalia, class Tritrichomonadea, order Tritrichomonadida, family Dientamoebidae/Protrichomonadinae) and, characterized by enteric and hepatic lesions in several species of domestic and wild gallinaceous. Among the most affected species, turkeys are those with greater morbidity and mortality. Blackhead is the second most important disease caused by protozoa in domestic poultry, affecting especially young birds and causing severe economic losses, with decrease in production, lack of uniformity of lots and costs with treatment and control. Its occurrence must be monitored, especially in large poultry exporting countries, such as Brazil. The aim of this study is to report an outbreak of histomoniasis in Indian peacocks.Case: A peacocks group created together with chickens showed clinical signs characterized by apathy, head down and bruised head, eyes closed, anorexia, yellow or pale stools and death. At necropsy, the cecum showed intense thickening of the wall with irregularity in the serous layer and abundant deposit of friable material, amorphous, yellowish color with areas reddish in the lumen with large number of filiform white parasites from 1 to 1.5 cm in length, morphologically compatible with Heterakis gallinarum. The liver showed large and circular, multifocal, whitish areas that extended towards the parenchyma. Histologically, was observed marked transmural typhlitis, severe proliferation of fibroblasts with multifocal neovascularization, histiocytic infiltrate, giant cell enlargement, bacterial myriads, presence of eosinophilic circulars trophozoites, with 6-20 μm in diameter, morphologically compatible with Histomonas meleagridis. These structures were positive in PAS staining.[...](AU)