ResumoA área da hemoterapia necessita de testes de compatibilidade sanguínea confiáveis, como a tipagem sanguínea, para se evitarem possíveis reações transfusionais, mas em felinos é também importante para se evitar a isoeritrólise neonatal. Transfusões sanguíneas realizadas entre felinos doadores e receptores que não possuem compatibilidade sanguínea podem refletir em reação transfusional aguda, particularmente severa quando o sangue tipo A é transfundido em um gato tipo B, pois geralmente este último possui altos níveis de aloanticorpos de ocorrência natural. Portanto, o conhecimento da frequência dos tipos sanguíneos da população de gatos de uma região pode auxiliar na determinação dos riscos de reações transfusionais e de ocorrência de isoeritrólise neonatal. Tais riscos podem ser prevenidos com a tipagem sanguínea em casos de transfusão. Foram coletadas 100 amostras sanguíneas de felinos para a realização da tipagem sanguínea com plasmas reagentes anti-A e anti-B conhecidas e titulações de aloanticorpos anti-A e anti-B dos plasmas armazenados. A distribuição das frequências dos grupos sanguíneos foi 96% de felinos com tipo sanguíneo A e 4% de felinos com tipo sanguíneo B, não sendo encontrado na amostra populacional de felino tipo AB. Há um grande risco de reação adversa através da transfusão sanguínea randomizada entre felinos não tipados previamente. Palavras-chave: gatos; imunohematologia; medicina transfusional; tipagem sanguínea. AbstractHemotherapy requires reliable blood compatibility tests, such as blood typing, to avoid possible transfusion reactions in cats. However, it is also important to avoid neonatal isoerythrolysis. When blood transfusions are performed between incompatible feline donors and recipients, they may develop acute transfusion reactions, especially severe when type A blood is transfused into a type B cat because it has high levels of anti-A alloantibodies. Therefore, knowing on the blood type frequency in feline population of some region can help to determine the transfusion reaction risks and the occurrence of neonatal isoerythrolysis. Addicionally, such risks may be prevented through blood typing, in cases of transfusion. One hundred feline blood samples were collected and anti-A and anti-B blood reagent typing tests were performed, plus titration of alloantibodies of stored plasma. These tests showed a 96% frequency of type A blood and only 4% of type B blood among tested cats. We did not find any AB type blood cat. There is a great risk of adverse reactions after random blood transfusions between non-typed cats.

Background: Primary tracheal tumors are considered uncommon in veterinary medicine and among them extranodal tracheal lymphoma, which is a neoplastic type, has rarely been described, especially with the use of immunophenotyping. Consequently, there is a lack of knowledge inherent to the characteristics of this tumor type in felines and as a result little information on how to deal with animals affected by this disease. Therefore, there is a need for more studies focusing on this matter. The objective of this work is to report a case of extranodal B cell lymphoma in the trachea of a domestic cat and point out the clinical and pathological characteristics of this neoplastic type.Case: A 5-year-old domestic cat, of an oriental breed, was taken to a veterinary clinic exclusively for cats in Rio de Janeiro, Brazil. The main complaint was difficulty in breathing and loss of appetite and historical data included intolerance to exercise. A clinical examination confirmed inspiratory dyspnea and upper respiratory sounds. Hematological and serum biochemical exams did not evidence any noteworthy changes and the cat was considered negative for feline viral leukemia and feline immunodeficiency viruses through serological and molecular testing. However, in the radiographic examination of the thoracic cervical region, an opacity was observed that occluded part of the tracheal lumen and this was suggestive of a mass in the initial third of the trachea, measuring 0.5 cm in diameter. The animal was stabilized and then 24 h after admission underwent inspection of the oral cavity and a biopsy of the tracheal mass was performed. Cytology of the specimen was suggestive of lymphoma. The treatment of choice was: lomustine with a single, oral dose of 10 mg; vincristine sulfate with a single intravenous dose of 0.75 mg/m²; and methylprednisolone acetate with a single intramuscular dose of 20 mg. A second radiograph taken 24 h after the chemotherapy showed that the tracheal mass had shrunk to 0.3 cm in diameter. Seven days after the treatment adopted for lymphoma, the mass was no longer visible. Histopathological analysis and immunohistochemistry supported the diagnosis of B cell lymphoma. A 36-month follow-up after the initial admission showed that the cat was in good health, without any respiratory signs and/or alterations in imaging tests that could suggest neoplastic recurrence.Discussion: The majority of animals with tracheal lymphoma are more than seven years old; thus, this report is one of the few that describes this tumor type in a young cat, and therefore highlights the importance of considering tracheal lymphoma as a differential diagnosis in young cats with clinical findings compatible with this condition. The successful treatment carried out here was attributed to the immunophenotyping of the neoplasia, because when B cell trachea lymphoma is diagnosed early and correctly there is usually a good prognosis. Type T lymphomas exhibit a poorer clinical response through therapy than B cell lymphomas. As far as the authors know, this is only the fifth report in which immunophenotyping of a tracheal lymphoma in a cat has been performed. The relevance of studies involving the immunohistochemistry of this tumor type in cats is asserted, so that the differentiation between B or T cell lymphomas can provide greater accuracy in dealing with animals affected with this disease.

Background: Histoplasmosis is a systemic mycosis whose etiologic agent is the fungus Histoplasma capsulatum. This fungal infection, which is the second most frequent systemic mycotic fungal disease in felines in the United States, has rarely been found in cats in Brazil. This paper reports on a case of acute pulmonary histoplasmosis in a domestic cat treated with oral itraconazole associated with amphotericin B administered subcutaneously. This treatment resulted in clinical remission of the patient’s symptoms, as evidenced by radiographic follow-ups.Case: A domestic cat suffering from acute dyspnea was taken to a veterinary clinic. The animal was subjected to emergency oxygen therapy, and kept at rest through sedation with midazolam. A physical examination revealed normally colored mucosa, 8% dehydration, bristly fur, body condition score 2/9, tachypnea with respiratory rate of 100 breaths per minute and expiratory dyspnea. The radiographic examination showed marked opacification of all the pulmonary fields, with a mixed pattern (interstitial and alveolar) of heterogeneous appearance and diffuse distribution, which are changes consistent with an inflammatory infectious process (pneumonia). A cytological analysis of the pleural fluid revealed round to oval-shaped intracytoplasmic structures, varying in size from 2 to 4 μm, inside foamy macrophages, consistent with Histoplasma capsulatum. Based on the diagnosis of pulmonary histoplasmosis, and in view of the patient’s acute respiratory distress, it was decided to treat the cat using itraconazole associated with amphotericin B. Itraconazole was administered orally at a dose of 100 mg/cat every 24 h, while amphotericin B was administered subcutaneously at a dose of 0.5 mg/kg, combined with 100 mL of sodium chloride 0.9% and 100 mL of 5% glycated serum, with monitoring of serum concentrations of symmetric dimethylarginine (SDMA). Amphotericin B was administered every 48 h up to the 7th dose, followed by three times a week up to the 11th dose, and then twice a week up to the 16th dose. The animal was released from the veterinary hospital 10 days after its admission, showing a considerably improved respiratory condition and a respiratory rate of 40 breaths per minute. Continuation of the antifungal treatment with itraconazole was prescribed, maintaining the same dose and frequency of administration until a new recommendation would be made, as well as frequent return visits for the administration of amphotericin B and reassessment of the animal. The administration of amphotericin B was discontinued when the animal’s respiratory condition stabilized; hence, the feline received a total of 16 doses of the drug. The animal showed remission of clinical respiratory symptoms, confirmed by follow-up chest X-rays, which revealed significantly less radiodense pulmonary parenchyma in response to treatment with itraconazole and amphotericin B. Five months after beginning its treatment, the cat is being treated orally with itraconazole (100 mg/cat, every 24 h), without recrudescence of the clinical symptoms.Discussion: To date, six cases of feline histoplasmosis have been reported in Brazil, only one of which had pulmonary involvement and was treated successfully. The use of oral itraconazole associated with subcutaneous amphotericin B has proved to be effective for the treatment of acute pulmonary histoplasmosis in domestic cats. Note that a rapid diagnosis of pulmonary disease is essential in order to immediately implement a combined drug therapy linked with monitoring to ensure the protocol is safe for the patient

Background: Cholangiocellular carcinoma is a malignant tumor that occurs mainly in elderly dogs and cats. Primary hepatobiliary neoplasms are considered rare in felines, although cholangiocarcinoma is the most common tumor type among malignant liver tumors in the species. The objective of this work is to report two cases of cholangiocarcinoma in young domestic cats, with three years old, and to approach clinical and pathological aspects to promote awareness of this type of injury in young animals, with a focus on prevention of predisposing factors. Cases: A 3-year-old male domestic cat (cat 1) had a history of progressive weight loss, persistent vomiting, diarrhea, and episodes of seizure. At the clinical examination was noted moderate degree of jaundice. In the biochemical exams it was verified as alteration hypoproteinemia, increase of urea and hyponatremia. Abdominal ultrasonography revealed a formation in the left epigastric region measuring 8.0 x 5.0 cm, with a diffusely heterogeneous parenchyma, suggestive of hepatic neoplasia, in addition to the presence of free abdominal fluid. Cavity fluid analysis was suggestive of carcinoma. A 3-year-old male domestic cat (cat 2), with history of hyporexia, emaciation and vomiting was taken to care. Physical examination showed moderate dehydration, hypocorous mucosa and presence of abdominal mass on palpation. The animal's serum biochemical assessment were verified as changes, increasing AST. Ultrasonographic examination showed an abdominal mass, located caudally to the spleen, with irregular shape, measuring approximately 4.7 cm suggestive of hepatic neoplasia, in addition to the presence of abdominal fluid. The hepatic cytology performed by fine needle aspiration was suggestive of carcinoma. After the clinical worsening of two cats and due unfavorable prognosis, euthanasia and necropsy were performed. In the macroscopic analysis of cat 1, numerous nodules of whitish and sometimes "umbilicate" coloration were observed in the liver, measuring up to three cm in diameter, distributed randomly by the hepatic parenchyma and with a soft consistency at cut. An ovoid-wicking mass, measuring 6.0 x 7.0 x 5.0 cm and coloring ranging from white to light brown was checked in omentum. In the macroscopic evaluation of cat 2, numerous coalescing masses of whitish coloring measuring up to 6.0 cm in diameter were observed covering almost every hepatic parenchyma and also affecting the pancreas, with a soft consistency at cut. The microscopic findings of both cats were compatible with the diagnosis of cholangiocarcinoma. Considering the immunohistochemical profile, in both cases there was positivity for the CK Pan antibody and CEA and negativity for the CK20, TTF-1, Hepatocyte specific antigen, CD10 and CD56 antibodies. Discussion: Cholangiocarcinomas usually occur in elderly animals, with a mean age of 9 years, so it may be suggested that the cause of the disease in cat 1 and 2 was possibly related to the early and continuous presence of carcinogens. The biliary duct trematod Platynoso...