Progressive angiomatosis, resembling human skeletal-extraskeletal angiomatosis, arising in multiple digits in two dogs.

Two dogs presented with progressive, expansile and invasive lesions on a hind paw. Case 1, a 10-year-old female Shetland sheepdog had diffusive and aggressive-looking lesions on the middle digits of the left hind paw. Radiographic examination showed invasion into and destruction of the underlying bone. A malignant tumour was suspected initially; however, histological features of atypical vascular proliferations without mitotic activity were consistent with progressive angiomatosis. Case 2, an 11-year-old female English springer spaniel presented with similar lesions in the same toes, also involving bone. Progressive angiomatosis was suspected clinically, as tumour cells were not detected by cytology and screening did not detect metastatic disease. Histopathology confirmed the diagnosis. Progressive angiomatosis is an uncommon non-malignant condition which should be considered as a differential diagnosis for radiographically lytic digital lesions.

A comparison of harmonic and traditional sharp staphylectomy techniques in 15 brachycephalic dogs.

OBJECTIVES: The objective was to compare sharp staphylectomy and staphylectomy using harmonic focus shears, assess surgical time, intraoperative haemorrhage and outcome. Our hypothesis was that harmonic staphylectomy would result in reduced surgical time, decreased intraoperative haemorrhage and greater relative improvement. MATERIALS AND METHODS: Dogs that were presented to Highcroft Veterinary Referrals between July 2020 and September 2021 with brachycephalic obstructive airway syndrome and underwent surgical correction were prospectively enrolled. Surgical technique was randomised, and surgical time, staphylectomy time, intraoperative haemorrhage, hospitalisation and change in patients' Cambridge BOAS Grade at a 14-day recheck were recorded. RESULTS: Fifteen dogs were enrolled: seven dogs underwent sharp and eight underwent harmonic staphylectomy. Nine patients returned for follow-up, four of seven and five of eight, respectively. Harmonic staphylectomy was associated with less haemorrhage (0 versus 9 cotton buds) and a shorter average staphylectomy time (3 minutes 36 seconds versus 14 minutes 50 seconds). No statistically significant differences were observed in total surgery time, number of nights hospitalised, or change in Cambridge BOAS Grade. An average of 0.68 mm of thermal necrosis was seen at the cut edges of soft palates removed by harmonic staphylectomy. CLINICAL SIGNIFICANCE: Harmonic staphylectomy can result in a reduction in staphylectomy time and degree of intraoperative haemorrhage compared to sharp staphylectomy, with no deleterious impact on postoperative recovery or the long-term outcome of patients.

Insulin expression in ß cells is reduced within islets before islet loss in diabetic cats.

OBJECTIVES: Diabetes mellitus is a common condition that requires intensive treatment and markedly impacts the welfare of affected cats. The aim of this study was to identify diabetes mellitus-associated perturbations in the feline pancreatic islet microenvironment. The utility of "clear, unobstructed brain/body imaging cocktails and computational analysis" (CUBIC) for three-dimensional pancreatic analysis was investigated. METHODS: Formalin-fixed paraffin-embedded tissues from cats with diabetes mellitus, or control cats without pancreatic pathology, were retrospectively identified. Immunohistochemistry for synaptophysin and ionised calcium binding adaptor molecule 1, and immunofluorescence for insulin and synaptophysin, were used to assess changes in islets. An image analysis pipeline was developed to analyse images acquired from two-dimensional immunofluorescence. CUBIC was used to optically clear selected pancreas samples before immunofluorescence and deep three-dimensional confocal microscopy. RESULTS: Diabetic cats have a significant reduction in synaptophysin-positive islet area. Whilst islets from diabetic patients have similar numbers of ß cells to islets from control cats, significantly lower intensity of insulin expression can be observed in the former. CUBIC facilitates clear visualisation of pancreatic islets in three dimensions. CLINICAL SIGNIFICANCE: The data presented support the theory that there is a decrease in function of ß cells before their destruction, suggesting a potentially significant step in the pathogenesis of feline diabetes mellitus. In parallel, we demonstrate CUBIC as a valuable new tool to visualise the shape of feline pancreatic islets and to interrogate pathology occurring in the islets of diabetic pets.

Skin masses in dogs under one year of age.

OBJECTIVES: To utilise a large histopathology database to ascertain the incidence and nature of skin masses in young dogs from 0 to 12 months of age. MATERIALS AND METHODS: A total of 2554 submissions received for histopathology from dogs 0 to 12 months of age, clinically diagnosed with a skin mass between 2006 and 2013, were retrieved from the database of a large commercial diagnostic laboratory. The histological diagnosis and site of the lesion, together with age, breed and sex of the dog were recorded. RESULTS: The most common skin mass found in this study was histiocytoma (n=2212, 86.6%). The majority of all submissions were neoplastic (n=2408, 94.3%), and most of those were benign (n=2372, 98.5%). Almost all of the benign neoplastic lesions were of round cell origin (n=2229, 94.0%) whereas most of the non-neoplastic lesions were derived from the epithelium (n=136, 93.8%). The five most commonly diagnosed skin masses in young dogs were histiocytoma, papilloma, dermoid cyst, follicular cyst and mast cell tumour. A male predisposition was shown for histiocytoma (odds ratio 1.72) and mast cell tumour (odds ratio 2.18) with a strong site predilection for the limb region (30.8% and 27.8% respectively). Dermoid cysts and follicular cysts were most commonly found in the skin of the abdomen (64.7% and 52.3% respectively) with boxers being predisposed (25.9% of dermoid cyst and 25.0% of follicular cyst). CLINICAL SIGNIFICANCE: A large proportion of skin mass submissions in young dogs were neoplastic and benign. Also, the most common skin mass in young dogs was found to be histiocytoma. Tumours can occur in this age group and should be considered as a potential differential diagnosis also in young patients presenting with a skin mass.

Prognostic significance of histopathology in canine anal sac gland adenocarcinomas: Preliminary results in a retrospective study of 39 cases.

Metastatic rates and survival times of canine anal sac gland adenocarcinomas (ASGACs) vary among studies, making prognostication difficult. Little is known about the prognostic significance of histopathology of ASGACs. This retrospective study investigated associations between histological features, clinical presentation and outcome for 39 ASGACs. Most tumours were incompletely excised (62%) and had moderate to marked peripheral infiltration (74%). The predominant growth pattern was solid, tubules/rosettes/pseudorosettes and papillary in 49%, 46% and 5% of the cases, respectively. Nuclear pleomorphism was either moderate (77%) or mild (23%). Necrosis and lymphovascular invasion were present in 54% and 10% of the cases, respectively. All histological features except mitotic count and necrosis were associated with nodal metastasis at presentation. A statistically significant poorer outcome was identified for tumours with a solid growth pattern, moderate or marked peripheral infiltration, necrosis and lymphovascular invasion. These results need further validation in a larger cohort of dogs.

Evaluation of Minichromosome Maintenance Protein 7 and c-KIT as Prognostic Markers in Feline Cutaneous Mast Cell Tumours.

Mast cell tumours (MCTs) are a common skin tumour in cats, but there is currently no histological grading system or reliable prognostic marker for this species (unlike the situation for dogs). This study utilized a set of 71 feline cutaneous MCTs with known clinical outcomes to assess the potential of various prognostic markers, including the cellular proliferation marker minichromosome maintenance protein (MCM)-7, mitotic index and various KIT labelling characteristics, including KIT positivity, KIT labelling pattern and KIT immunoreactivity score (IS). Of the factors studied, the mitotic index and the KIT labelling pattern were the only features associated significantly with survival times, while the proliferation marker MCM7 and the KIT IS were not. The study also highlights the variability of KIT labelling characteristics between tumours, which may prevent use of this marker as a diagnostic and prognostic tool.

Assessing portable blood glucose meters for clinical use in cats in the United Kingdom.

The aims of this study were to evaluate six portable blood glucose meters for use in cats in a clinical setting and to identify potential sources of inaccuracy such as the effect of glucose concentration and haematocrit. Excess fluorinated whole-blood samples were obtained and were tested using the six meters and a reference laboratory method. Bland-Altman plots were constructed and an error grid analysis was performed, using a grid adapted in this study for diabetic cats. Error grids are a clinically oriented non-parametric approach to blood glucose data, and are designed to determine whether differences between glucometer and laboratory readings are clinically significant. All the meters studied had the potential to under- or overestimate blood glucose levels to varying degrees throughout the glycaemic range. This variation was not consistent enough to be predictable and correctable. The study failed to demonstrate any link between haematocrit and difference between laboratory and glucometer readings.

The use of magnetic resonance imaging in the management of pharyngeal penetration injuries in dogs.

OBJECTIVES: To investigate the correlation between the magnetic resonance imaging findings and subsequent surgical findings for a series of dogs presenting with suspected pharyngeal stick injuries to the Animal Health Trust, Newmarket, between 1995 and 2004. METHODS: Magnetic resonance imaging findings were reviewed for patients undergoing a scan of the pharyngeal or cervical area for suspected foreign bodies during the years 1995 to 2004. RESULTS: Case signalment, history and clinical signs were similar to those reported in previous studies. Magnetic resonance imaging demonstrated foreign material in six of seven cases where this was present. There was good correlation between diagnosis of a foreign body at magnetic resonance imaging and subsequent surgical identification. CLINICAL SIGNIFICANCE: Compared with other imaging modalities, magnetic resonance imaging is very helpful for this type of injury, especially in chronic cases where radiographic evidence of a foreign body is unlikely. It is a valuable aid in the diagnosis of pharyngeal penetration injury and in surgical planning.

The E5 oncoprotein of BPV-4 does not interfere with the biosynthetic pathway of non-classical MHC class I.

The major histocompatibility complex (MHC) class I region in mammals contains both classical and non-classical MHC class I genes. Classical MHC class I molecules present antigenic peptides to cytotoxic T lymphocytes, whereas non-classical MHC class I molecules have a variety of functions. Both classical and non-classical MHC molecules interact with natural killer cell receptors and may under some circumstances prevent cell death by natural killer cytotoxicity. The E5 oncoprotein of BPV-4 down-regulates the expression of classical MHC class I on the cell surface and retains the complex in the Golgi apparatus. The inhibition of classical MHC class I to the cell surface results from both the impaired acidification of the Golgi, due to the interaction of E5 with subunit c of the H+ V-ATPase, and to the physical binding of E5 to the heavy chain of MHC class I. Despite the profound effect of E5 on classical MHC class I, E5 does not retain a non-classical MHC class I in the Golgi, does not inhibit its transport to the cell surface and does not bind its heavy chain. We conclude that, as is the case for HPV-16 E5, BPV-4 E5 does not down-regulate certain non-classical MHC class I, potentially providing a mechanism for the escape of the infected cell from attack by both cytotoxic T lymphocytes and NK cells.