A 9-year-old female mixed breed dog presented for an acute onset of anorexia, vomiting, and cough. Initial examination and diagnostics revealed a large multilobular cranial mediastinal mass with unidentified fungal organisms on cytology. The disease progressed in spite of therapy until the dog was euthanized 8 months later. Gross necropsy findings were a large multilobular intrathoracic mass, mild pleuritis, and generalized lymphadenopathy. Histologic evaluation showed granulomatous inflammation and necrosis with numerous 20- to 70-micron, periodic acid-Schiff- and Gomori methenamine silver-positive spherules effacing lymph node parenchyma, as well as severe inflammation within the midbrain. Endosporulation was a common finding, and large numbers of fungal hyphae were also present in affected areas. Ribosomal RNA gene sequencing found 100% identity to published sequences of Phanerochaete chrysosporium, the teleomorph form of Sporotrichum pruinosum. This is the first published report of disease caused by natural infection with this basidiomycete organism in animals.

A nine-year-old spayed female labrador retriever presented with marked paraparesis. Radiographic imaging revealed regions of osteolysis within the spinous process of the L1 vertebra and the lamina and pedicles of the T13 vertebra. Cytological examination of the bone marrow exhibited a marked increase in plasma cells; histopathology of a core needle biopsy from the L1 spinous process revealed normal bone marrow findings with only scattered plasma cells. The serum biochemical profile demonstrated multiple abnormalities, some of which are frequently observed in cases of multiple myeloma such as hypercalcaemia and hyperglobulinemia. Initial serum protein electrophoresis (SPE) exhibited a tall, narrow peak of the β-1 region superimposed onto a broad total β globulin base. The SPE also demonstrated a second α-2 spike and low γ fraction. Although a urinalysis revealed a significant proteinuria, the patient lacked a Bence Jones proteinuria. The combined diagnostic workup was consistent with multiple myeloma.

No abstract