Criptococose sistêmica em um canino da raça Miniatura Schnauzer / Systemic cryptococcosis in a Miniature Schnauzer dog

ABSTRACT

Background: Cryptococcosis is an important zoonotic disease that occurs worldwide. The disease is caused by a soilborne opportunistic fungus of the genus Cryptococcus, which can also be found in the feces of birds, especially pigeons. In Brazil, the geographical distribution of the agent is fairly defined, with the species C. gattii predominantly found in the north-eastern states. Diagnosis is based on the clinical history, physical examination findings, and results of complementary testing, such as cytopathological and histopathological examinations. This report aims to describe the clinical and anatomopathological findings in a case of systemic cryptococcosis in a dog.Case A 4-year-old female Miniature Schnauzer was referred for necropsy. For 3 months prior to death, the dog had displayed generalized alopecia, pruritus, and severe weight loss, Initially, a private veterinarian had suspected leishmaniasis. Gross examination was performed and samples for cytopathology, histopathology, and fungal culture were obtained. The macroscopic examination revealed generalized alopecia, congested mucosa, cachexia, hyperemia of the brain, and multiple white nodules measuring 0.5 cm to 4 cm in the lungs and the kidneys. None of the other organs showed significant lesions. Cytopathological examination of the nodules revealed a highly cellular sample, with a severe chronic inflammatory response, characterized by multinucleated giant cells and round-to-elliptical, yeast-shaped structures (5-10 µm), suggestive of Cryptococcus organisms. Histopathological examination of the lungs, kidneys, and brain revealed a severe diffuse chronic inflammatory process, with lymphocytic infiltration and multinucleated giant cells; countless yeast-shaped, round-to-ovoid structures (similar in appearance to “soap bubbles”) that were negative in hematoxylin-eosin stain were also present.[...]