Management of canine perianal fistula with fluorescence light energy: preliminary findings

In vitro evaluation of bactericidal effects of fluorescent light energy on Staphylococcus pseudintermedius and S. aureus

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.

Successful treatment of perianal fistulas in two dogs with oclacitinib

Perianal fistula (PAF) formation in dogs is a frustrating and painful disease, occurring primarily in German shepherd dogs. Ciclosporin has become the recommended treatment of choice yet may be associated with numerous adverse effects. This case report describes the successful treatment of two cases of PAF with oclacitinib.

Exploring fluorescent light energy as management option for canine superficial bacterial folliculitis

Superficial bacterial folliculitis (SBF) represents a common dermatological diagnosis in dogs that can be successfully managed with either topical and/or systemic treatments. In the present study we evaluated the efficacy of a fluorescent light energy (FLE) device as sole management for SBF. The same FLE device has been shown, as adjunct therapy to systemic antibiotic or alone, to effectively control clinical manifestation of interdigital furunculosis. Twenty dogs were randomized to receive FLE once (six dogs) or twice (six dogs) weekly in comparison with oral anti-biotic (eight dogs) until complete healing. FLE regimen was able to significantly reduce the time needed to clinical resolution for oral antibiotic, supporting owners' compliance and welfare of dogs.

Fluorescent Light Energy in the Management of Multi Drug Resistant Canine Pyoderma: A Prospective Exploratory Study

The increase in prevalence of staphylococcal antimicrobial resistance has been also associated with pyoderma in dogs, and prolonged antibiotic treatment, as often needed in severe cases of pyoderma, has been related to influencing possible development of multidrug resistance (MDR). Fluorescent light energy (FLE) has been indicated to improve pyoderma lesions as adjunct therapy to systemic antibiotics. In the present study, we evaluated the effect of FLE on clinical signs of MDR canine deep pyoderma (CDP) and interdigital furunculosis (CIF) when administered as solely management. Sixteen client-owned dogs affected by CIF (five dogs) and CDP (eleven dogs) were scored using a dedicated scoring system and received a single FLE applications twice weekly, until clinical resolution was achieved. Mean time to achieve complete resolution was 5.20 ± 3.56 weeks (median 3 weeks) for CIF cases and 4.18 ± 1.47 weeks (median 4 weeks) for CDP ones. FLE shows promise as an aid to managing clinical signs while reducing reliance on antibiotics for MDR CDP and CIF. In this study, FLE was responsible for the decrease in lesion scores and resolution of MDR pyoderma infection without any adjunct therapy, having a potential useful role to play in antibiotic stewardship programs, efficiently promoting complete clinical resolution of MDR lesions while optimizing the use of antibiotics.

Critically Appraised Topic on Low-Level Laser Therapy (LLLT) in Dogs: An Advisable Treatment for Skin Diseases?

Simple Summary

Low-level laser therapy (LLLT) is a therapeutic technique with reported regenerative, anti-inflammatory, antibacterial, and analgesic effects. In the last few years, LLLT has been used in dogs for the management of different skin lesions and diseases. This study reports a literature review using the critically appraised topic (CAT) method to determine the canine skin diseases for which LLLT is an advisable treatment. Only primary clinical prospective studies were considered. A meticulous literature search revealed 19 significant clinical trials, and these were critically analyzed. The evaluation of the best accessible evidence in July 2022 suggests that LLLT can be a promising and effective adjunctive treatment in combination with systemic antibiotic therapy for canine interdigital pyoderma and canine deep pyoderma. Furthermore, the use of LLLT is not recommended as a therapy for pedal pruritus secondary to canine atopic dermatitis. In other canine skin diseases, there is a possible helpful effect of LLLT; however, the evidence for its use is not currently convincing.

Abstract

Low-level laser therapy (LLLT) is a therapeutic option that stimulates cellular function through intracellular photobiological and photochemical reactions, promoting better tissue repair and an anti-inflammatory, antibacterial, and analgesic effect. Previous studies in human and veterinary medicine have shown the clinical efficacy of LLLT in many fields. In this study, the literature was reviewed using the critically appraised topic (CAT) method to determine the canine skin diseases for which LLLT is an advisable treatment. A meticulous literature search revealed 19 significant clinical trials, which were critically analyzed. The evaluation of the best accessible evidence in July 2022 suggests that fluorescence biomodulation (FBM), a type of LLLT, can, in combination with systemic antibiotic therapy, be a promising and effective adjunctive treatment for canine interdigital pyoderma and canine deep pyoderma. Furthermore, the evidence suggests that the use of LLLT is not recommended as a therapy for pedal pruritus secondary to canine atopic dermatitis. For other canine skin diseases included in the CAT, although LLLT appears to be a promising treatment, there is not yet good scientific evidence to recommend its use.

Fluorescence Biomodulation for Canine Interdigital Furunculosis: Updates for Once-Weekly Schedule

Interdigital furunculosis is a common multifactorial, inflammatory disease of the canine interdigital skin in which lesions commonly become secondarily infected. Fluorescence biomodulation (FBM) administered twice weekly has shown to effectively control clinical manifestation as adjunct therapy to systemic antibiotic. Since twice weekly regimen could be unaffordable for some pet owners, the aim of this study was to evaluate the effect of once weekly application of FBM in combination with systemic antibiotic on clinical manifestations of canine interdigital pyoderma, comparing the results to those present in literature. Twelve dogs diagnosed with interdigital pyoderma received antibiotic plus once weekly FBM application. Dogs were scored until complete healing based on global lesion score and neutrophil engulfing bacterial score. The results obtained demonstrated that once weekly application of FBM exerts the same beneficial effect on interdigital furunculosis healing as per twice weekly, indicating that once weekly regimen is well tolerated and is yielding similar results to twice weekly applications.

Current Applications and Future Perspectives of Fluorescence Light Energy Biomodulation in Veterinary Medicine

The purpose of this review is to determine the state of the art of the mode of action and potential applications of fluorescence photobiomodulation in veterinary medicine. After a summary of the assets that have led the translation of such light-based therapies from bench side into clinical use, recent advances in canine dermatology using this brand-new approach are presented, and future scenarios where this type of care may provide benefits over the current standard care are highlighted.

The Effectiveness of Fluorescent Light Energy as Adjunct Therapy in Canine Deep Pyoderma: A Randomized Clinical Trial

A single centre, single-blinded, prospective, randomized, controlled clinical study was conducted to evaluate the effectiveness of twice weekly fluorescent light energy therapy (Phovia™) as adjunct to systemic antibiotics in the management of deep pyoderma in dogs. Dogs with clinical lesions consistent with deep pyoderma, positive bacterial culture, and showing neutrophil engulfing bacteria at cytology were included in the study. Assessments were undertaken weekly for 8 weeks and every 2 weeks thereafter until 12 weeks after enrolment. At each visit, lesions were scored and cytology was conducted to determine a neutrophil engulfing bacteria score. All dogs (Groups A and B) were treated with systemic antibiotic twice daily, and Group B received additionally Phovia twice weekly. Median treatment duration was 11.7 weeks for Group A and 5.7 weeks for Group B. After 8 weeks of treatment, the percentage of dogs that achieved clinical resolution was 35.0% and 88.0% for Groups A and B, respectively. Lesion scores showed highly statistically significant difference in favour of Group B from week 3 to 8, and neutrophil engulfing bacteria scores showed statistical difference from week 2 onwards in favour of Group B. These results indicate that Phovia, when used as an adjunct to systemic antibiotics, can accelerate time to clinical resolution in cases of canine deep pyoderma.