Lumbosacral plexus block using a combination of ultrasound-guided lateral pre-iliac and parasacral approaches in cats.

OBJECTIVE: To describe an ultrasound-guided lateral pre-iliac (LPI) and parasacral (PS) approach in feline cadavers (phase I) and compare the perioperative analgesic use and complications in cats administered LPI and PS blocks (group PNB) or epidural anesthesia (group EPI) for pelvic limb surgery (phase II). STUDY DESIGN: Experimental uncontrolled, anatomic and retrospective cohort study. ANIMALS: A group of eight feline cadavers and 52 medical records. METHODS: Bilateral LPI and PS approaches with 0.1 mL kg-1 of dye to stain the femoral and obturator nerves and the lumbosacral trunk, respectively, were performed on each cadaver. Nerve staining effect was evaluated upon dissections (phase I). Perioperative analgesics use, and complication rates were retrospectively compared between groups PNB and EPI (phase II). Continuous data were compared using the Mann-Whitney U test and the prevalence of events with Fisher's exact test. Differences were considered significant when p < 0.05. RESULTS: Dissections revealed that the LPI approach stained 94% and 75% of the femoral and obturator nerves, respectively. The PS approach stained 100% of the lumbosacral trunks. Cats enrolled in group PNB (n = 23) were administered lower doses of intraoperative opioids than those in group EPI (n = 25) (p = 0.006). Intraoperative rescue analgesia was required in 60% and 17.4% of cats enrolled in groups EPI and PNB, respectively (p = 0.003). Group PNB required more intraoperative anticholinergics than group EPI (p = 0.02). There were no differences in postoperative pain scores, analgesic use and complication rates. CONCLUSIONS AND CLINICAL RELEVANCE: The ultrasound-guided LPI and PS approach stained the femoral/obturator nerves and the lumbosacral trunk, respectively, in feline cadavers. Furthermore, PNB was associated with lower intraoperative opioid use and similar postoperative pain and analgesic use compared with epidural anesthesia in a cohort of cats undergoing surgery of the pelvic limb.

MORTALITY INVESTIGATION OF MONITORED EASTERN BOX TURTLES (TERRAPENE CAROLINA CAROLINA) IN CENTRAL ILLINOIS, USA, FROM 2016-18.

Mortality events in eastern box turtles (Terrapene carolina carolina) threaten conservation efforts across the species range. These events are often under-diagnosed and, when observed, predictive health factors are unavailable prior to death. At Kickapoo State Park in central Illinois, USA, ranaviruses caused observed mortality events in amphibians and chelonians in 2014 and 2015. Following these outbreaks, eastern box turtles (n=36) were affixed with radio transmitters and temperature data loggers to obtain repeated location and temperature data from spring 2016-spring 2018. Bimonthly, samples of blood and oral and cloacal swabs were collected to investigate health parameters (hematology and cytokine transcription) and presence of multiple pathogens. Deaths of instrumented turtles occurred in 2016 (n=5), 2017 (n=15), and 2018 (n=2). The largest single die-off occurred in February 2017 (n=7). Seventeen turtles were necropsied and multiple pathologic processes were identified, most frequently decreased adipose stores (n=6). Two turtles had pathologic findings consistent with multisystemic inflammation. In addition, infectious pathogens were identified in turtles prior to death, but no single agent was associated with each mortality event. Ranavirus was not detected in any turtle. Hot spot analysis revealed spatial clustering at the center and edges of the study area for body temperature as well as for relative cytokine transcription of interleukin-1 beta, tumor necrosis factor alpha, and interleukin-10 associated with turtle death. Though no single causal factor could be identified, the information from this mortality event can direct future chelonian mortality investigations by providing baseline longitudinal data prior to death and in surviving turtles.

Understanding the Efficiency of Splenic Hemangiosarcoma Diagnosis Using Monte Carlo Simulations.

Hemangiosarcoma is a common neoplasm of the spleen in older dogs. However, diagnosis is complicated by necrosis and hemorrhage, which can mimic a number of benign processes. Currently, there is no consensus about the number of sections pathologists should examine to rule out hemangiosarcoma. To answer this question, we examined 413 histopathologic sections from 50 cases of canine hemangiosarcoma (mean: 8.1 sections per case; range, 5-14). Each section had the presence or absence of hemangiosarcoma determined by 2 board-certified anatomic pathologists. Then, 100 Monte Carlo simulations were performed, randomly selecting sections from each case 10 000 times and the results averaged. These simulations suggest that examination of 5 sections from a spleen with hemangiosarcoma yields a 95.02% chance of diagnosing hemangiosarcoma, while examination of 10 sections yields a 98.59% chance of diagnosis when hemangiosarcoma is in fact present. The data emphasize the need to submit the entire spleen for histopathologic examination in suspected cases of hemangiosarcoma and suggest that 5 sections obtained by a trained individual are likely sufficient for diagnosis.

Prevalence of CD20+ cutaneous epitheliotropic T-cell lymphoma in dogs: a retrospective analysis of 24 cases (2011-2018) in the USA.

BACKGROUND: Limited information is known about the baseline frequency of canine CD20 positive (+ ) cutaneous epitheliotropic T-cell lymphoma. A single canine case report has been published. OBJECTIVES: To characterize the baseline frequency of CD20+ staining in cases of canine cutaneous epitheliotropic T-cell lymphoma; to assess its values as a prognostic indicator. ANIMALS: Skin biopsies from 24 client-owned animals diagnosed with cutaneous epitheliotropic lymphoma were assessed. METHODS AND MATERIALS: A retrospective review of medical records from 2011 to 2018. Clinical histories and previous histological and immunohistochemical slides were collected from 24 dogs and additional immunohistochemical staining was performed as needed to assess cases of cutaneous epitheliotropic T-cell lymphoma for CD3, CD20, CD79a and PAX5 staining characteristics. Staining characteristics were assessed for their statistical relationship to median survival time. RESULTS: Overall median survival time was 189 days following the onset of clinical signs and 99 days following definitive diagnosis; 54% of cases had CD20+ staining. There was no statistically significant correlation between staining characteristics and median survival time from onset of signs (P = 0.54) or from diagnosis (P = 0.61). CONCLUSIONS AND CLINICAL SIGNIFICANCE: Canine cutaneous epitheliotropic lymphoma has a higher instance of CD20 positivity than documented previously. This indicates that CD20 staining may be unsuitable to differentiate T-cell and B-cell cutaneous epitheliotropic lymphoma. This also may have therapeutic implications with the advent of canine CD20 monoclonal antibody therapies.

FOXA2 depletion leads to mucus hypersecretion in canine airways with respiratory diseases.

Because of exposure to environmental pollutants, infectious agents, and genetic predisposition, companion animals develop respiratory illnesses similar to those in humans. Older dogs of smaller breeds develop canine infectious respiratory disease, chronic bronchitis, and chronic obstructive pulmonary disease, with chronic lung infection, airway goblet cell hyperplasia and metaplasia, and mucus hypersecretion. Excessive mucus clogs airways, reduces gas exchanges, disables the mucociliary clearance, and reduces drug penetration. The Forkhead box protein A2 (FOXA2) is a key transcriptional regulator that maintains airway mucus homeostasis. Prior studies have shown that FOXA2 expression is frequently depleted in diseased human airways. Unfortunately, FOXA2 depletion has not been examined in dogs. Our current study indicated that both single bacterial infection by Pseudomonas aeruginosa and Bordetella bronchiseptica and polymicrobial infection by viral/bacterial pathogens depleted FOXA2 in canine airways, resulting in goblet cell hyperplasia and metaplasia and excessive mucus production. Furthermore, P. aeruginosa virulence factor pyocyanin activated the antagonistic STAT6 and epidermal growth factor receptor signalling pathways to inhibit FOXA2. Unravelling the mechanism of FOXA2 inactivation will hasten the development of non-antibiotic therapeutics to improve mucociliary clearance of pathogens in canine airway.

Comparing dermoscopy and histological examination of normal equine skin.

BACKGROUND: Dermoscopy is a noninvasive diagnostic technique that allows visualization of structures of the superficial dermis not visible with the naked eye. HYPOTHESIS/OBJECTIVES: To assess the usefulness and applicability of dermoscopy for evaluation of healthy equine skin. ANIMALS: Twelve healthy horses from a research herd. METHODS: Five regions (cheek, lateral neck, dorsum, flank and abdomen) were examined with contact dermoscopy using both nonpolarized and polarized light at both 17-fold and 24-fold magnification. These findings were compared to histological features of skin biopsies cut both longitudinally and transversely. RESULTS: Using a hand-held dermatoscope with nonpolarized light, epidermal ridges were observed. Using polarized light, follicular openings and distinctly separate epidermal openings of sweat gland ducts were observed in some but not all individuals. Similarities were noted between histological and dermoscopic results. CONCLUSIONS: Although not ideal for visualizing many structures in the superficial dermis of healthy equine skin, dermoscopy allowed visualization of epidermal ridges, hair shafts in the infundibular portion of the hair follicles and sweat gland duct openings. Dermoscopy could potentially be useful in the evaluation of diseases affecting the sweat glands, epidermis and hair shaft.

Pagetoid reticulosis (epitheliotropic cutaneous T-cell lymphoma) in an adult alpaca (Vicugna pacos).

A 9-year-old, intact female alpaca (Vicugna pacos) was presented for a second opinion with a 1-year history of nonpruritic, multifocal scaling and crusted cutaneous lesions, mainly involving skin on the face, axillae, and ventral abdomen. Clinical abnormalities were limited to the skin, and the alpaca was otherwise healthy. The initial veterinarian had examined the alpaca, found no evidence of ectoparasites with laboratory testing, and had tried several trial therapies including oral antibiotics, ivermectin, and topical use of betadine solution. At the time of presentation, the lesions had neither improved nor worsened with any attempted therapy, and multiple skin biopsies were collected. Histopathology and immunohistochemical staining findings were consistent with the pagetoid reticulosis type of cutaneous epitheliotropic T-cell lymphoma. Our report describes the clinical, histopathologic, and immunophenotypic features of pagetoid reticulosis epitheliotropic cutaneous T-cell lymphoma in an alpaca.

Coordinate expression of cytokeratins 7 and 14, vimentin, and Bcl-2 in canine cutaneous epithelial tumors and cysts.

Forty-seven canine cutaneous epithelial tumors and cysts were examined to determine coordinate expression of cytokeratins 7 (CK7) and 14 (CK14), vimentin, and Bcl-2 using commercially available antibodies. Within non-affected normal skin adjacent to tumors or cysts, CK7 expression was observed in luminal cells in apocrine glands; CK14 expression was observed in the stratum basale, stratum spinosum, stratum granulosum, basal layer of outer root sheath, sebaceous glands, and myoepithelial cells of apocrine glands; vimentin expression was observed in dermal papilla and scattered non-epithelial cells within the epidermis; and Bcl-2 expression was observed in scattered non-epithelial cells in the epidermis and some apocrine glands. The pattern of expression of CK7 and CK14 in cases of adenocarcinoma of the apocrine gland of the anal sac (CK7+/CK14-) and hepatoid gland tumors (CK7-/CK14+) may prove useful for diagnostic purposes. Loss of expression of CK14 and vimentin, identifying myoepithelial cells, was observed in apocrine and ceruminous adenocarcinomas. Differences in patterns of expression of Bcl-2 were observed between infundibular keratinizing acanthomas compared to trichoepitheliomas.

Pancreatic carcinoma in an African clawed frog (Xenopus laevis).

This report describes the histologic features of a pancreatic carcinoma in an adult female African clawed frog (Xenopus laevis). The animal was found to be in poor body condition and subsequently euthanized for a complete necropsy. Histologically, the pancreas was effaced by packets of polyhedral cells consistent with a pancreatic islet cell carcinoma. Metastatic disease was not identified. Pancreatic tumors are uncommon in amphibians, and this report is the first to describe a pancreatic carcinoma in an African clawed frog.

Evaluating the clinical and physiological effects of long term ultraviolet B radiation on guinea pigs (Cavia porcellus).

Vitamin D is an important hormone in vertebrates. Most animals acquire this hormone through their diet, secondary to exposure to ultraviolet B (UVB) radiation, or a combination thereof. The objectives for this research were to evaluate the clinical and physiologic effects of artificial UVB light supplementation on guinea pigs (Cavia porcellus) and to evaluate the long-term safety of artificial UVB light supplementation over the course of six months. Twelve juvenile acromelanic Hartley guinea pigs were randomly assigned to one of two treatment groups: Group A was exposed to 12 hours of artificial UVB radiation daily and Group B received only ambient fluorescent light for 12 hours daily. Animals in both groups were offered the same diet and housed under the same conditions. Blood samples were collected every three weeks to measure blood chemistry values, parathyroid hormone, ionized calcium, and serum 25-hydroxyvitamin D3 (25-OHD3) levels. Serial ophthalmologic examinations, computed tomography scans, and dual energy x-ray absorptiometry scans were performed during the course of the study. At the end of the study the animals were euthanized and necropsied. Mean ± SD serum 25-OHD3 concentrations differed significantly in the guinea pigs (p<0.0001) between the UVB supplementation group (101.49±21.81 nmol/L) and the control group (36.33±24.42 nmol/L). An increased corneal thickness in both eyes was also found in the UVB supplementation compared to the control group (right eye [OD]: p<0.0001; left eye [OS]: p<0.0001). There were no apparent negative clinical or pathologic side effects noted between the groups. This study found that exposing guinea pigs to UVB radiation long term significantly increased their circulating serum 25-OHD3 levels, and that this increase was sustainable over time. Providing guinea pigs exposure to UVB may be an important husbandry consideration that is not currently recommended.

Use of surgery and mitoxantrone chemotherapy in a dog with disseminated lymphangiosarcoma.

CASE DESCRIPTION: A 5-year-old sexually intact male Giant Schnauzer was evaluated because of difficulty breathing and left pelvic limb swelling. Eighteen months previously, the patient had had intermittent left pelvic limb swelling, but the owner declined further testing at that time. CLINICAL FINDINGS: Physical examination revealed severe pitting edema of the left pelvic limb and prepuce and muffled heart sounds on thoracic auscultation. Results of thoracic radiography and thoracocentesis were consistent with chylothorax, and CT imaging of the thorax and abdomen revealed a mass involving the whole left sublumbar area. TREATMENT AND OUTCOME: In an attempt to treat the chylothorax, pleural omentalization and pericardectomy were performed. Histologic evaluation of several biopsy specimens harvested in the abdominal and thoracic cavities revealed disseminated lymphangiosarcoma. The patient recovered well from surgery, and mitoxantrone chemotherapy was administered. As of 10 months after surgery, the dog was clinically normal except for mild pelvic limb edema. CLINICAL RELEVANCE: The combination of clinical signs, multiple imaging features, surgical findings, and histologic examination findings enabled the final diagnosis of lymphangiosarcoma. Clinical management that included medical and surgical treatments and chemotherapy resulted in improved quality of life and extended survival time in a dog with metastatic lymphangiosarcoma.

Canine intravascular lymphoma with overt leukemia.

A 6-year-old spayed Labrador Retriever Mix dog was evaluated for a 2-week history of progressive generalized weakness and reluctance to stand. Physical examination revealed severe weakness with obtunded mentation, head tilt, bilateral nystagmus, and decreased vision. CBC findings included mild nonregenerative anemia, marked thrombocytopenia, and a few atypical mononuclear cells on the blood film. The cells were 15-30 µm in diameter and had round to oval to reniform centrally placed nuclei with stippled chromatin, prominent nucleoli, and abundant basophilic cytoplasm with numerous discrete vacuoles and, occasionally, small azurophilic granules. Similar cells were found in bone marrow. On histologic examination of tissues collected at necropsy, neoplastic cells were detected in bone marrow, hepatic sinusoids, cerebral and meningeal vessels, and in capillaries of the heart, renal interstitium, small intestinal submucosa, and muscularis, and alveolar septa. A small discrete mass in the right atrium consisted of similar neoplastic cells, and the spleen was diffusely infiltrated. Tissue distribution was suggestive of intravascular lymphoma. Neoplastic cells in tissue sections were immunoreactive for vimentin, CD18, CD45, and granzyme B and lacked immunoreactivity for cytokeratin. Neoplastic cells on bone marrow aspirate smears and blood films lacked immunoreactivity for CD3, CD79a, CD1c, CD11b, CD11c, CD11d, and E-cadherin. In the absence of immunophenotypic evidence for the neoplastic cells being derived from B-cell, T-cell, or histocytic/dendritic lineages and the lack of clonal antigen receptor gene rearrangement(s), along with positive immunoreactivity for granzyme B, a tumor of NK cells was considered likely. Based on current knowledge, this is the first report of canine intravascular lymphoma, of probable NK cell origin, with peripheral blood involvement.

Metastatic ductal adenocarcinoma in a Western Hognose snake (Heterodon nasicus).

A 17-yr-old Western Hognose snake (Heterodon nasicus) presented with a prominent midcoelomic swelling. Surgical exploration revealed a large, multicystic, irregular, tan, and firm mass grossly effacing the splenopancreas. The mass was subsequently removed. Histologically, the mass was composed of tubules of columnar to flattened neoplastic cells with an abundant stroma and moderate cellular atypia consistent with a scirrhous adenocarcinoma, likely ductal in origin, given the location of the neoplastic mass. Bloodwork revealed anemia, monocytosis, marked hypercalcemia, and, postoperatively, persistent hyperglycemia. After postoperative recovery, the snake was diagnosed with iatrogenically induced diabetes mellitus and exocrine pancreatic insufficiency. Due to the inability to clinically control the diabetes mellitus and exocrine pancreatic insufficiency and when additional palpable masses were noted, the snake was euthanatized. Necropsy and histopathologic examination confirmed metastasis of the previously removed adenocarcinoma to the liver, right kidney, and large intestine.

A retrospective study of disease in captive kangaroos from Oklahoma State University, 1995-2009.

The antemortem biopsy records (5 cases) and necropsy records (34 cases) were reviewed from 39 kangaroo case submissions during a 14-year period to the Oklahoma State University and the Oklahoma Animal Disease Diagnostic Laboratory. The most common types of diseases in the kangaroos, based on necropsy examination, was disease of the alimentary tract (12 cases), pneumonia (6 cases), and disseminated toxoplasmosis (5 cases). The cause of disease was not determined in 6 case submissions. Based on histopathologic findings, clostridial enteritis/colitis was suspected in 2 kangaroos. Coccidian parasites were identified within histologic sections of the small intestine in 1 kangaroo. Pasteurella sp. (1 case) and Bacteroides sp. (1 case) were isolated from the lung in 2 cases of pneumonia. Most (77.3%) of disease in this study in the kangaroos with known ages occurred in animals older than 1 year. Two neoplasms were detected in the antemortem biopsy samples from 1 case.

Disseminated cutaneous mast cell tumors with epitheliotropism and systemic mastocytosis in a domestic cat.

A 15-year-old female domestic, medium-haired cat presented to the referring veterinarian with a 2-month history of multiple, raised, disseminated, nodular skin lesions. A biopsy of 1 of the lesions was submitted to the Oklahoma Animal Disease Diagnostic Laboratory for evaluation. Histologically, there were multiple dermal nodules composed of sheets of neoplastic round cells. Multifocally, the neoplastic cells formed multiple small clusters of 3 to 5 cells within the epidermis. Distinct cytoplasmic granules were evident within the neoplastic cells with toluidine blue and Giemsa stains. The neoplastic cells were immunoreactive for c-KIT and lacked immunoreactivity for cluster of differentiation 3 with immunohistochemistry. Based on these findings, multiple epitheliotropic cutaneous mast cell tumors were diagnosed. The cat's health declined rapidly despite aggressive treatment, and the animal was humanely euthanatized. A complete necropsy revealed sheets of similar neoplastic mast cells within the spleen, liver, and individual cells scattered within the bone marrow. Exon 11 of the c-KIT messenger RNA from 1 of the cutaneous masses and the spleen was amplified with reverse transcription polymerase chain reaction, sequenced, and compared with the published c-KIT messenger RNA sequence from fetal cat tissues. The maximum identity was 100% for both tissue samples. To the authors' knowledge, the present report is the first to describe disseminated cutaneous mast cell tumors with epitheliotropism and systemic mastocytosis in a domestic cat.

Malignant melanoma of the subcutaneous tissues in an umbrella cockatoo (Cacatua alba).

A 24-year-old female umbrella cockatoo (Cacatua alba) was examined because of a subcutaneous swelling of the left shoulder. Radiographs of the left wing revealed boney proliferation of the left proximal humerus. At surgery, an unencapsulated infiltrative nonpigmented mass within the subcutaneous tissue and skeletal muscle was identified overlying the left humerus. The mass was surgically excised and submitted for histologic examination; however, the cockatoo died after excision. Histologically, the mass was composed of nests and sheets of pleomorphic neoplastic cells with a high mitotic index and extensive necrosis. Rare neoplastic cells contained fine brown cytoplasmic granules that stained black with Fontana-Masson, confirming the presence of melanin pigment. The histomorphologic diagnosis was consistent with an anaplastic malignant melanoma of subcutaneous tissues.