Case report: Multidrug-resistant Streptococcus pseudoporcinus isolated from an infected surgical wound of a 9-year-old spayed female Great Dane dog.

Streptococcus pseudoporcinus (S. pseudoporcinus) is a ß-hemolytic, Gram-positive novel bacterium first identified in 2006. It is a catalase-negative, non-motile coccus arranged in short chains. Furthermore, it has a broad beta-hemolytic reaction on sheep blood agar and cross-reacts with Lancefield group B antigen agglutination reagent. In this study, we report a case of S. pseudoporcinus infection of a surgical wound on the left metatarsus of a dog. The patient is a 9-year-old spayed female Great Dane dog with a brief history of multiple cutaneous masses being removed. Post-surgery, the post-surgical site on the left metatarsus became infected and discharged purulent material with a fetid odor. Upon preliminary diagnostic testing, we detected catalase-negative Gram-positive cocci exhibiting beta-hemolytic growth on sheep blood agar. A VITEK® 2 Compact machine from bioMérieux identified the bacterium as S. pseudoporcinus. Furthermore, antibiotic testing revealed multidrug resistance. Therefore, we document a multidrug-resistant S. pseudoporcinus isolate as a cause of canine post-surgical wound infection. Furthermore, it was the only isolate detected from the sample; hence, it is the cause of the infection. To our knowledge, this case is the first report of S. pseudoporcinus in a dog.

Osteosarcoma diagnosed in a dog using a formalin-fixed fine-needle aspirate biopsy.

BACKGROUND: Fine-needle aspirate (FNA) biopsy is considered a quick technique to access and identify the cell types present in a pathologic lesion or make a diagnosis. Often, clinicians want to know if they are dealing with an inflammatory lesion with or without infectious agents or a neoplastic lesion. At times, neoplastic lesions may be confounded by the presence of inflammatory cells. OBJECTIVES: We aimed to evaluate the application of a formalin-fixed FNA, designated the cytologic/histopathologic (CytoHisto) technique, to determine the diagnostic quality and ability to arrive at a definitive diagnosis without the use of concentrated cell block or invasive full tissue biopsy procedures during sample collection. METHODS: A 10-cc syringe with a 22-gauge 1-inch needle attached was used to obtain a sizable FNA biopsy sample from a thigh mass in a dog. The needle was removed from the syringe, and the material was expulsed from the syringe directly into 10% buffered formalin. After 24-48-h fixation, a strainer was used to facilitate placement of the fixed granular material into a micromesh biopsy processing/embedding cassette, and the sample was processed as a routine histopathology sample. A microtome was used to make thin sections stained with H&E initially. Then, subsequent sections were stained with immunohistochemical (IHC) stains vimentin, MUM1, and CD18. Alkaline phosphatase staining was performed on a previously Wright's-stained cytology following IHC results. All sections were coverslipped and viewed under a light microscope. RESULTS: When unable to perform incisional or excisional biopsies, this CytoHisto, FNA in formalin technique was useful for collection and subsequent processing as a histopathology sample, with sectioning and then staining with H&E and IHC stains. Neoplastic cells were strongly immunoreactive for vimentin but negative for MUM1 and CD18. Scattered leukocytes within the background stained positively with CD18. CONCLUSIONS: The CytoHisto technique is minimally invasive and allows for sectioning similar to a full-thickness excisional or incisional biopsy with subsequent H&E and IHC staining, and special stains allow for a definitive diagnosis of osteosarcoma. The CytoHisto technique is a practical diagnostic technique to pursue in clinical practice that minimizes patient invasiveness and maximizes sample collection time, similar to the routine FNA technique.

T-cell lymphoma-associated hemophagocytic syndrome in an American Pit Bull Terrier.

A 3-y-old, intact female, American Pit Bull Terrier was presented because of acute onset of anorexia and a large subcutaneous submandibular mass that had been present for 3 wk. The submandibular mass, 2 engorged black-legged ticks on the dorsum of the neck, pyrexia, and icterus were seen on physical examination. Abnormal laboratory test results included a positive Anaplasma antibody test, severe thrombocytopenia, mild nonregenerative anemia, hyperbilirubinemia, and elevated liver enzyme activities. Cytology of the mass was interpreted as marked septic purulent inflammation with acute hemorrhage. Treatment with doxycycline for anaplasmosis was unsuccessful, and the patient died at an emergency follow-up visit 2 d after the initial presentation. Autopsy and histopathology revealed widespread metastasis of a presumptive histiocytic neoplasm with associated hemophagocytosis seen in lymph nodes (LNs), liver, and spleen. Immunohistochemistry yielded a definitive diagnosis of a CD3+/CD18+ T-cell lymphoma. In this case of canine lymphoma-associated hemophagocytic syndrome, hemophagocytes were observed as >2% of neoplastic cells in the liver, spleen, and LN histologically, a scarce or unreported finding, to our knowledge. The prognosis was grave, with a short survival time after the onset of clinical signs.

An uncommon occurrence of bicavitary effusion due to mast cell neoplasia in a 12-year-old mixed breed dog.

A case of bicavitary effusion affecting a 12-year-old female spayed mixed breed dog that was presented to Tuskegee University College of Veterinary Medicine's Emergency Service for abdominal distension and vomiting. Upon physical exam, the patient exhibited signs of pain and sensitivity to touch and pain on abdominal palpation with a positive fluid wave. The patient also had dull mentation and increased respiratory effort with an abdominal component. On labwork, there was a leukocytosis characterized by a mature neutrophilia, monocytosis, and basophilia. A mild thrombocytopenia with low numbers of poorly granulated mast cells were also noted on peripheral blood smear review. Serum biochemistry revealed a mild azotemia and abnormal SNAP cPL test. The patient received a full abdominal ultrasound, which detected bicavitary effusion, hepatomegaly, and splenomegaly. Cytology of the cavitary effusions was moderately cellular with significant numbers of mast cells. The patient was euthanized following a tentative diagnosis of systemic mastocytosis. The clinical signs, in this case, are consistent with published data for systemic mastocytosis, which include organomegaly, abdominal pain, gastrointestinal signs, and hematologic abnormalities. However, this is the first report of bicavitary effusion due to presumed systemic mastocytosis.

The cytologic and histologic diagnosis of ureteral fibroepithelial polyp in a dog.

A 6-year-old, intact male, brindled, 30-Lb English Bulldog presented to the Purdue University Veterinary Teaching Hospital with a recurrent history of hematuria, periuria, and lethargy that responded temporarily to antibiotic therapy. The work-up included a complete blood count, serum biochemical profile, complete urinalysis, diagnostic imaging (abdominal radiographs and ultrasound with contrast urography), and exploratory laparotomy. The diagnostic imaging findings and subsequent exploratory revealed a unilateral, intraluminal, right-sided, 3-cm ureteral mass extending from the proximal ureter into the renal pelvis. Subsequently, a unilateral right-sided ureteronephrectomy followed by biopsy with cytopathology/cytology (impression smears) and histopathology of the ureteral mass was performed. The cytopathologic interpretation was benign mesenchymal proliferation with mildly atypical urothelial cells. The association of this mass with vascular tissue and a benign nuclear appearance on cytology is similar to reports of fibroepithelial polyps (FEPs) and myxomatous tumors. Histopathology diagnosed the mass as an FEP. Cytopathology proved useful in the presumptive diagnosis of this benign urothelial polyp. To the authors' knowledge, this is the first report using cytopathology to depict and characterize FEPs in veterinary and human medical literature.

Synovial fluid from an African spur-thighed tortoise (Geochelone sulcata).

A 4.5-year old, male African spur-thighed tortoise (Geochelone sulcata) was presented to the University of Florida Veterinary Teaching Hospital with a 2-week history of lethargy, anorexia, constipation, dyspnea, and coughing up fluid or vomiting. Laboratory results included an inflammatory leukogram and a marked increase in plasma uric acid concentration. Synovial fluid from multiple joints was thick, chalky white, and opaque, with a grainy consistency. Microscopically, the fluid contained numerous brown, needle-like crystals consistent with urates (gout). Gross necropsy findings and histopathology confirmed a diagnosis of systemic gout, with urate deposition, gout tophi, and underlying necrosis in multiple organs, including kidneys, lung, and liver. Dehydration with concurrent renal insufficiency may have impaired urate excretion and led to a build-up of urates in the blood and tissues of this tortoise. A high protein diet also may have contributed to the development of gout. Cytologic evaluation of synovial fluid can be used as a quick and definitive tool to diagnose gout in tortoises.