Following treatment for pneumonia, a 1-y-old female Nubian goat was presented because of a persistent fever for 3 mo and peripheral lymphadenopathy for 1 mo. Cytology and histology of the superficial cervical and prefemoral lymph nodes demonstrated a moderate-to-marked “left-shifted” lymphoid population, suggestive of lymphoma, and extremely rare extracellular, 2–4 µm, oval, basophilic yeast, consistent with Histoplasma capsulatum. On immunohistochemistry, >95% of the lymphocytes demonstrated positive cytoplasmic and membranous immunoreactivity for CD3. Histoplasma spp. urine antigen and serum antibody testing were positive and negative, respectively. Panfungal PCR and sequencing of DNA extracted from scrolls of formalin-fixed, paraffin-embedded tissue yielded matches to H. capsulatum with 99–100% identity. Given the poor prognosis and persistent pyrexia, the animal was euthanized. Postmortem examination confirmed concurrent multicentric, intermediate-size, T-cell, lymphoblastic lymphoma and histoplasmosis; lesions consistent with intestinal coccidiosis and suspected pulmonary Rhodococcus equi were also noted. Although dimorphic fungi have been described previously in goats, lesions of Histoplasma spp. had not been documented in this species, to our knowledge. Given the low disease burden, it is suspected that the lymphoma was primary, leading to an immunocompromised state and development of secondary, opportunistic infections.

In this study, we describe a multimodal approach to diagnose a unique case of myeloma‐related disease, extranodal secretory B‐cell lymphoma with urinary bladder involvement, an IgG4 monoclonal gammopathy, and Bence‐Jones proteinuria in a dog with a 6‐year history of hyperglobulinemia that had not been further evaluated. A 12‐year‐old dog was presented for evaluation of a 1‐week history of tenesmus. Urine sediment cytologic evaluation revealed low to moderate numbers of intermediate to large‐sized lymphocytes. We describe a technique that yielded adequate numbers of viable neoplastic cells in shipped urine sediment for PARR and flow cytometry. Those studies demonstrated a clonal immunoglobulin gene rearrangement and an expansion of CD21‐positive and MHC Class II‐negative B cells, respectively. Protein electrophoresis with immunofixation and proteomic evaluation revealed a serum and urine IgG4 monoclonal gammopathy with Bence‐Jones proteinuria. MUM1 immunocytochemistry performed on the urine sediment slides failed to label the neoplastic cells; thus, a plasma cell tumor was considered unlikely. Lack of response to a cyclophosphamide, vincristine, and prednisone chemotherapy regimen led to euthanasia without necropsy 21 days after diagnosis. Lymphoma is the most common hematopoietic malignancy and accounts for up to a quarter of all neoplasms in dogs, but lymphoid neoplasms arising primarily from extranodal sites are infrequently reported. Urinary tract neoplasia can be diagnosed by urine evaluation in about one‐third of canine cases, but the diagnosis of lymphoid neoplasia via urine evaluation is rarely reported. This case highlights the utility of ancillary diagnostics on urine for detection of lymphoid malignancies.

A 2-year-old female spayed Boxer dog was presented to the Texas A&M University Veterinary Medical Teaching Hospital for further investigation of chronic hemorrhagic diarrhea of 6 weeks duration and significant weight loss despite previous administration of antibiotics (oxytetracycline, sulfadimethoxine/ormetoprim and metronidazole), a single dose of steroids (dexamethasone), a vitamin B12 injection, maropitant, fluid therapy, and prescription diet trials. Complete blood counts and fecal flotations performed by the referring veterinarian were unremarkable. The dog resided in a multi-dog household and was primarily indoors with access to large areas of agricultural land with livestock and stagnant water bodies. All other dogs in the household were apparently healthy. Physical examination revealed a 3/9 body condition score and a thickened colonic wall on digital rectal examination. A sinus Abstract A 2-year-old female spayed Boxer dog was presented for a 1-month history of progressive hemorrhagic diarrhea with tenesmus and weight loss despite trial courses of antibiotics and diet change. Abdominal ultrasound revealed severe, focal thickening, and loss of normal architecture of the colonic wall with abdominal lymphadenomegaly. Dry-mount fecal cytology, performed on several consecutive days, consistently revealed numerous, round, 16-20 μm structures with basophilic, granular content, and a thin cell wall. Transmission electron microscopy identified these structures as fungi. Culture, polymerase chain reaction (PCR), and sequencing of the internal transcribed spacer, D1/D2 regions, and DNA-directed RNA polymerase II core subunit (RPB2) confirmed the presence of Basidiobolus microsporus in the feces. Biopsies collected via ileocolonoscopy revealed marked, multifocal, chronic, neutrophilic, and eosinophilic ileitis and colitis with ulceration, granulation tissue, and intralesional hyphae (identified with Gomori methenamine silver stain). A Pythium enzyme-linked immunosorbent assay and Pythium-specific PCR performed on the formalin-fixed paraffin-embedded biopsy specimens were positive while Basidiobolus-specific PCR was negative, thus confirming a diagnosis of pythiosis. This report describes a fatal case of colonic and intestinal pythiosis infection with the presence of fecal Basidiobolus sp. spores, suggestive of concurrent gastrointestinal basidiobolomycosis infection. K E Y W O R D S canine, diarrhea, oomycosis, zygomycosis

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