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Background: Aspergillus spp. are dimorphic fungus widely distributed in the environment, including in soil, dust and decaying vegetation. Clinical signs of aspergillosis in horses including rhinitis, pneumonia, guttural pouch mycosis, keratomycosis, endometritis, abortions and systemic involvement. In addition, horses with a history of enterocolitis may be predisposed to pulmonary or systemic mycotic infection. However, reports about systemic aspergillosis in horses are restricted to infections by A. fumigatus and A. niger. There have been no reports of systemic infection caused by A. flavus in horses or in other domestic species. Thus, the objective of this work was to describe the epidemiological, clinical and pathological aspects of systemic infection by Aspergillus flavus in a mare. Case: A 3-year-old pregnant mare of the Manga Larga, had signs of colic two days prior to admission after grazing in a landfill area to which it had free access. The owner observed remains of plastic bags in the stool. Clinically, there was dehydration, apathy, ocular mucosal congestion, oral cyanosis, reluctance to move, diarrhea, fever, drooling and tachypnea. Due to its clinical condition, the animal was referred to the surgical center for exploratory laparotomy, where compaction in the colon and cecum was verified. Enterotomy and enterolith removal were performed in the small colon region. The mare died after eight days of hospitalization, and necropsy was performed. Macroscopically disseminated lesions were observed in the small colon, stomach, kidneys, lungs, heart and brain. Fragments of tissues from organs in the abdominal and thoracic cavities, as well as from the central nervous system, were collected, fixed in 10% buffered formalin solution, and subsequently routinely processed and stained with hematoxylin and eosin and special histochemical stains to visualize the infectious agent and its morphological characteristics. Samples of lung lesions were submitted to microbiological culture for isolation. Fragments of fungal colonies were conserved in mineral oil for molecular analysis. Histologically, lesions showed acute, necrosuppurative colitis, gastritis, pneumonia, myocarditis, nephritis and meningoencephalitis, associated with vasculitis, thrombosis, infarction and intralesional hyphae that were morphologically compatible with Aspergillus spp. The species A. flavus was identified based on isolation and polymerase chain reaction analysis. Discussion: A diagnosis of systemic aspergillosis caused by Aspergillus flavus was determined by the microscopic examination of lesions associated with characteristic intralesional fungal hyphae and the isolation and identification of the fungal DNA by PCR. A pre-existing disease associated with debilitating factors, including the period of pregnancy, postpartum stress, internment, surgery and the intensive use of antimicrobials and corticosteroids, probably contributed to immunosuppression that favored the proliferation of the infectious agent. Grazing for a long period of time in a place with abundant decomposing organic matter, which is favorable to the proliferation of fungi of the genus Aspergillus, may have been a determining factor leading to the infection in the present case as the animal was likely exposed to an excessive number of spores. It is believed that the fungal microorganisms already present in the gastrointestinal tract invaded the surgery-induced lesions present in the mucosa of the small colon and later disseminated to various organs, including heart, lungs, stomach, kidneys and brain. Aspergillus flavus can cause enteric infection and hematogenous dissemination in horses, triggering lesions in the heart, lungs, stomach, kidneys and brain, which are characteristic of the systemic form of aspergillosis. [ABSTRACT FROM AUTHOR]

Background: Candida spp. are pleomorphic fungi that are commensal inhabitants of the oral, gastrointestinal, upper respiratory and urogenital mucosa of mammals. Candida albicans is described as the most important species. This opportunistic pathogen may produce local or systemic infections in dogs. Local infections have been reported in several tissues and systemic infection is rare in dogs with few reports in the literature describing this presentation. The aim of the present study was to report two cases of cerebral Candida albicans infection in dogs in Brazil. Case: Two cases of cerebral Candida albicans infection in dogs that showed nervous signs are described. In both cases, the brain showed marked asymmetry of the telencephalic hemispheres with multifocal to coalescing yellowish or reddish areas and a partial loss of distinction between gray and white matter. In Case 1, the mediastinal, tracheobronchial and mesenteric lymph nodes, as well as the right kidney and adrenal gland, showed altered architecture due to numerous whitish gray nodules. Histological lesions were characterized by granulomatous (case 1) or pyogranulomatous (case 2) necrotizing meningoencephalitis with intralesional fungal organisms. In case 1, similar granulomatous infiltrate with intralesional fungal organisms was also seen in the lymph nodes, kidney and adrenal gland. In case 2, there was evidence consistent with an underlying infection of canine distemper virus. Were observed lymphoplasmocytic interstitial pneumonia, lymphoid rarefaction in lymph nodes, and viral intracytoplasmic inclusion bodies in the epithelial cells of the stomach and vesical urothelium. In these two cases, the fungal organisms displayed three different morphological patterns. The first pattern was characterized by delicate tubular structures with thin parallel walls that were rarely septate and tended to undulate slightly, and measured approximately 4-20 µm (true hyphae). The second pattern was characterized by chains of elongated yeast, separated by constrictions at septal sites, and measured approximately 4-10 µm (pseudohyphae). The other morphological pattern, which was rarely observed, was characterized by round budding yeast cells that measured 3-4 µm in diameter and were often elongated by the germ tube. Sections were also stained using immunohistochemical antibodies against Candida albicans. The fungi revealed strong immunolabelling of the cytoplasm and wall for Candida albicans. Discussion: The diagnosis was based on the histomorphological and immunohistochemical characteristics of the agent, which were consistent with Candida albicans. In these two cases, immunocompromise appeared to have been an important factor in the progression of the infection. In case 1, the dog was senile and treated with corticosteroids, conditions that could effectively limit innate, humoral and cell-mediated immune response to infection. In case 2, the dog displayed cachexia and was infected by canine distemper virus, evidenced by the presence of viral inclusion bodies. The inflammatory reactions in both cases were characteristic of fungal infections, but were distinct due to differences in the infectious process. In case 1, there was a subacute to chronic progression; while in case 2 neutrophilic infiltrate predominated, suggesting an acute progression. The different morphological patterns of the fungi suggested a pleomorphic fungi and the immunohistochemistry allowed us to identify the infectious agent. In conclusion, opportunistic infections caused by Candida albicans should be considered when diagnosing diseases that affect the central nervous system of dogs, particularly in immunosuppressed animals. [ABSTRACT FROM AUTHOR]

The identification of tumors requires the use of practical diagnostic techniques for early evaluation of these lesions. Cytology is the best option to achieve this goal due to its simplicity, fast results, low invasiveness and costs. This work aimed to evaluate the epidemiologic aspects and determine the prevalence of skin palpable lesions and soft tissue lesions of the dog population treated at Unidade Hospitalar Veterinária (UHV) of Universidade Estadual do Ceará (UECE). There were forms filled with the lesions aspects and epidemiologic information of the animals. In total, 262 samples were collected of 186 animals that presented skin and soft tissue palpable lesions. The prevalence in dogs without breed standard was high in this study, a number about 55.4% of all animals, followed by the breeds Poodle, Pitbull and Cocker Spaniel. Of all concluded diagnoses, 184 were neoplastic lesions, 57 non-neoplastic and 21 were non-representative. Of the neoplasms, 22.3% were classified as epithelial origin, 34.8% were mesenchyme origin diagnosed and 45.1% were round cells tumors. Considering the anatomic regions, was observed that most of the samples were collected from the hind limbs, with a 11.9% rate. With this study, we conclude that neoplastic lesions were more prevalent in comparison with the non-neoplastic ones and the round cells tumors were found to be the most prevalent. Among the round cell tumors, the mast cell tumor was the most prevalent which shows the high incidence of this kind of neoplasm in dogs. [ABSTRACT FROM AUTHOR]