Seven of 60 Perendale sheep within a flock developed single or multiple exophytic masses on their distal hind limbs. A mass was excised from one sheep and histological evaluation revealed epidermal and mesenchymal proliferation, papillomavirus-induced keratinocyte changes and marked keratohyalin clumping. Ovis aries papillomavirus type 2 DNA sequences were amplified using PCR.
Background: A combination of dermoscopic and histological findings may provide useful information for the diagnosis of hair follicle diseases. However, there are no studies on dermoscopic-histopathological correlations in dogs affected by alopecia X, and comparison of longitudinal versus transversal sectioning of skin biopsy specimens in the assessment of this hair loss disorder has not been thoroughly investigated.
Hypothesis/objectives: The aim of this study was to correlate dermoscopic and histological features using both longitudinal and transversal sectioning of skin biopsy samples to gain additional information for the diagnosis of alopecia X.
Animals: Nineteen Pomeranian dogs affected by alopecia X and five healthy Pomeranians as controls.
Materials and methods: Dermoscopic-histological correlation was performed within the diseased group, whereas histological comparisons against controls. The demographic and clinical characteristics also were related to the histological findings.
Results: The dermoscopic findings revealed scattered, thinned, short hairs mixed with amorphous keratoseborrhoeic-like material (follicular plugging), perifollicular and intrafollicular scaling, and hyperpigmentation varying from pinpoint black spots to a diffuse texture. Dermoscopic findings correlated with histological findings for selected qualitative and quantitative findings. The usefulness of transversal sections was demonstrated in accurately determining the hair follicular density and counts, growth arrest phases and in identifying mineralisation of hair follicle basement membrane when compared to the longitudinal. Conversely, no correlations between histological findings and demographic and clinical characteristics were detected.
Conclusions and clinical relevance: These data provide evidence of the usefulness of dermoscopic evaluation as an accessory diagnostic tool and of transversal sections of skin biopsies as complementary to the diagnosis of alopecia X.
Straelensia cynotis is a trombidioid mite that causes painful, usually nonpruritic nodular dermatitis mainly in the dorsal region of dogs. This case report describes the first observation of feline straelensiosis in Europe with clinicopathological findings. Molecular characterisation of the parasite was performed and compared with mites collected from dogs.
Canine cutaneous lupus erythematosus (CCLE) is a well-described, yet uncommon, autoimmune disease which can present clinically with different variants. This case report describes the clinical and histopathological presentation, and treatment response, of CCLE affecting a novel location, the interdigital skin, in two unrelated greyhounds.
Background: Staphylococcus pseudintermedius and S. aureus are bacterial species of importance in veterinary medicine. The increasing incidence of antibiotic resistance necessitates the implementation of novel treatment modalities. Fluorescent light energy (FLE) is used as an adjunctive and primary treatment for canine pyoderma. However, no in vitro studies exist investigating its bactericidal effects against S. pseudintermedius or S. aureus.
Objectives: To determine the bactericidal effects of FLE on S. pseudintermedius and S. aureus isolates.
Materials and methods: Two meticillin-susceptible S. pseudintermedius (MSSP) isolates, three meticillin-resistant S. pseudintermedius (MRSP) isolates and one meticillin-resistant S. aureus (MRSA) isolate were studied. A commercially available blue light-emitting diode (bLED) lamp and photoconverting hydrogel FLE system was used. All bacteria were exposed to five conditions following inoculation: (i) no treatment (control); (ii) blue light (bLED) once; (iii) bLED twice consecutively; (iv) FLE (bLED and photoconverting hydrogel) once; and (v) FLE (bLED and photoconverting hydrogel) twice consecutively. Each individual exposure was 2 min long.
Results: No statistically significant differences (p < 0.05) were found for any treatment group when each bacterial isolate was evaluated individually, MSSP isolates were grouped, MRSP isolates were grouped, when all S. pseudintermedius isolates were combined, or when all isolates of both Staphylococcus species were combined.
Conclusions and clinical relevance: While clinical success is reported when using FLE to treat Staphylococcus infections in animals, no in vitro antibacterial efficacy was identified for S. pseudintermedius or S. aureus under experimental conditions. The clinical success observed with FLE may be the result of a more complex in vivo response.
Background: Artificial intelligence (AI) has been used successfully in human dermatology. AI utilises convolutional neural networks (CNN) to accomplish tasks such as image classification, object detection and segmentation, facilitating early diagnosis. Computer vision (CV), a field of AI, has shown great results in detecting signs of human skin diseases. Canine paw skin diseases are a common problem in general veterinary practice, and computer vision tools could facilitate the detection and monitoring of disease processes. Currently, no such tool is available in veterinary dermatology.
Animals: Digital images of paws from healthy dogs and paws with pododermatitis or neoplasia were used.
Objectives: We tested the novel object detection model Pawgnosis, a Tiny YOLOv4 image analysis model deployed on a microcomputer with a camera for the rapid detection of canine pododermatitis and neoplasia.
Materials and methods: The prediction performance metrics used to evaluate the models included mean average precision (mAP), precision, recall, average precision (AP) for accuracy and frames per second (FPS) for speed.
Results: A large dataset labelled by a single individual (Dataset A) used to train a Tiny YOLOv4 model provided the best results with a mean mAP of 0.95, precision of 0.86, recall of 0.93 and 20 FPS.
Conclusions and clinical relevance: This novel object detection model has the potential for application in the field of veterinary dermatology.
Background: Topical therapy is essential in assisting with the resolution of pyoderma.
Objectives: (i) Evaluate the in vitro efficacy and residual activity of two different hair segments treated with shampoo and mousse against meticillin-sensitive and meticillin-resistant staphylococci; (ii) compare proximal and distal hair portions treated with the products and (iii) describe a new disc diffusion method for assessing residual efficacy.
Animals: Eleven privately owned, medium-haired dogs.
Materials and methods: In this randomised, blinded and negatively controlled study, dogs were treated once with a 3% chlorhexidine digluconate-0.5% ophytrium shampoo on the lateral thorax, and the corresponding mousse on the opposite side. Hairs were plucked before treatment, two hours post-treatment, and day (D)2, D4, D7, D10 and D14. Hairs were weighed (0.01 g) and cut (1.0 cm) from the proximal portion, moistened with saline and placed on a sterile diffusion disc to absorb the solution. Proximal and distal hair bundles and diffusion discs were placed onto agar inoculated with an isolate of meticillin-sensitive or meticillin-resistant Staphylococcus pseudintermedius or Staphylococcus schleiferi. Inhibition zones were measured following incubation.
Results: Distal hairs had larger (p < 0.001) inhibition zones compared to proximal hairs. Mousse had significant differences (p < 0.05) between time points and locations for both the hair bundles and discs, while shampoo only had a significant difference (p < 0.001) between time points for the hairs.
Conclusions and clinical relevance: Mousse was effective, and shampoo was only minimally effective in inhibiting bacterial growth in vitro, with the greatest effect occurring at the two hours time point. The distal hair shafts had greater inhibition.
Background: Nonexcisional tissue biopsies facilitate pre-operative confirmation of equine sarcoid yet fear of lesion deterioration currently limits its use in the diagnostic workup.
Objectives: To evaluate the effect of a single punch biopsy on tumour growth dynamics [thickness, area, circumference, viral load (VL) and Visual Analog Scale (VAS)].
Animals: Six client-owned horses with 11 sarcoids of various classification.
Materials and methods: Growth dynamics were recorded on a weekly basis, 12 weeks pre- and 24 weeks post-biopsy. The effect of a single punch biopsy on growth dynamics was estimated by linear mixed-effect models. Spearman's rank correlation coefficient (SRCC) was calculated to investigate correlations with the number of weeks before and after the intervention.
Results: While statistically significant post-biopsy changes were recorded for all parameters except VL, no parameter was consistently increased after the biopsy intervention. In two of 11 sarcoids, the VL correlation pattern revealed significant strong correlations: sarcoid 6 (pre: r = -0.66, p < 0.05; post: r = 0.81, p < 0.001), increased VL; and sarcoid 8 (pre: r = 0.85, p < 0.001; post: r = 0.17, p > 0.05), no further increase after biopsy.
Conclusions and clinical importance: Our results indicate that post-biopsy lesion deterioration is not a general concept that applies to all sarcoids, and both deterioration or improvement are possible outcomes over a 24-week period. Further clinical studies with a larger sample size are needed before a definitive conclusion can be made.
Successful treatment of pemphigus foliaceus (PF) often requires a multimodal therapeutic approach. The dog described herein underwent four therapeutic plasma exchange treatments for severe, refractory PF, resulting in a 50% reduction of lesional body surface area. This treatment option should be considered for the management of canine PF.