Diagnosis and treatment of dermatophytosis in dogs and cats.: Clinical Consensus Guidelines of the World Association for Veterinary Dermatology

Feline dermatoses at Ferdowsi University of Mashhad (Iran): 154 cases (2009-2020)

BACKGROUND

Studies indicate that 6% to 20% of feline patients have at least one dermatopathy.

HYPOTHESIS/OBJECTIVE

This retrospective study aimed to provide comprehensive information about the types of skin diseases, diagnosis methods, treatments and follow-up data in a hospital population of domestic cats in Iran.

ANIMALS/MATERIALS AND METHODS

The present survey of clinical observations was conducted on the medical records of 1825 individual cats brought to the Faculty of Veterinary Medicine, Ferdowsi University of Mashhad (Iran) over a 12-year period (2009-2020).

RESULTS

Feline dermatoses accounted for 154 (8.43%) of the 1,825 cats examined during the study period. The most prevalent dermatological manifestations in the studied population of 154 were erythema, macules, papules and/or pustules (36; 23.37%), alopecia (18; 11.68%) and erosive/ulcerative lesions (17; 11.03%). Specific dermatological diagnoses made were the following (in descending order, of 154): dermatophytosis (34; 22.07%), subcutaneous abscesses (16; 10.38%), atopic skin syndrome/environmental allergies (20; 10.38%), external parasites (15; 9.74%), otitis (10; 6.49%), flea infestation (6; 3.89%), food allergy (4; 2.59%) and primary pyoderma (2; 1.29%). Most lesions were observed in the head/face of cats (41 of 154; 26.62%) and their ears (39; 25.32%). Following treatment, 86 of 154 cats (69.35%) had complete remissions, 17 cats faced recurrent dermatoses and the owners of 21 cats were not satisfied.

CONCLUSIONS AND CLINICAL RELEVANCE

The prevalence of dermatoses among this cohort of Iranian cats is similar to that in other parts of the world. However, a noticeable difference was detected in the most prevalent dermatoses. To the best of our knowledge, this is the first study to assess the characteristics and outcomes of feline dermatological conditions in Iran.

Zoonoses and pet owners: A survey on risk perception in Northern Italy

Veterinary and human medicine are focused on the issue of emerging and re-emerging diseases, which are especially represented by zoonosis that could be a threat for public health. Zoonotic risk may come from pets: some canine and/or feline viral, bacterial, parasitic, protozoal or mycotic diseases can be transmitted directly to humans. There are several strategies to prevent the transmission of such zoonosis, and among them vaccination plays an important role. Through a survey carried out in Northern Italy aimed to collect information regarding owners' knowledge and perception of the zoonotic risks associated with three zoonoses (rabies, leptospirosis, and dermatophytosis), it was demonstrated that dog owners tend to adhere more consistently to their pets' vaccination schedules and are more receptive to changes in vaccination scheduling compared to cat owners. This study also suggests that cat owners predominantly visit veterinarians for vaccination purposes, whereas dog owners seek veterinary services for a variety of reasons. The survey highlighted the ongoing need to enhance owners' understanding of zoonoses affecting their pets and also the protective role of vaccines. Veterinarians should undertake the responsibility of educating, reassuring, and informing pet owners about the significance of vaccines for their pets and for public health.

Dermatophytosis in domestic cats: Identification, and treatment in an Indian context

The surge in domestic cat adoption across India, particularly the rising preference for high-pedigree cats, coupled with environmental factors, has resulted in increased incidence of dermatophytosis among feline companions. Despite this growing concern, there is a noticeable scarcity of studies in India delving into the etiological factors contributing to dermatophytosis in cats. This disease is a threat to animal health and carries public health significance, given that cats are recognized reservoir hosts for Microsporum canis, a common dermatophyte affecting humans and animals. This study endeavours to identify the dermatophytes affecting cats and establish a standardized therapeutic regimen while accounting for the local stigma surrounding the regular bathing of cats. The study involved the examination of 82 cats presenting dermatological lesions, when subjected to cultural examination in dermatophyte test medium revealed 36 afflicted with dermatophytes. Isolates were presumptively identified by staining using lactophenol cotton blue, Chicago sky blue 6B, and Calcofluor white stains. Molecular-level identification of the isolates was confirmed through PCR-RFLP, amplifying the Internal Transcribed Spacer Sequence of 16 s rDNA, followed by restriction digestion using the Mva1 enzyme. Among the thirty-six isolates, 29 were identified as M. canis, while the remaining 7 were M. gypseum. The cases were categorized into five groups and treated with Lime Sulphur dip, 4 % chlorhexidine shampoo, a shampoo containing 2 % miconazole and 4 % chlorhexidine, oral itraconazole alone, and a combination of oral itraconazole with lime-Sulphur dip. Statistical analysis revealed that the response was notably swifter with lime Sulphur dip when considering only topical therapy. Moreover, the mycological cure was most expeditious when combining Lime Sulphur dip with oral itraconazole. These findings underscore the pivotal role of topical biocides in feline dermatophytosis treatment, potentially reducing the reliance on specific antifungals and thereby contributing to the mitigation of antimicrobial resistance emergence.

The Fungal Secretory Peptide Micasin Induces Itch by Activating MRGPRX1/C11/A1 on Peripheral Neurons

Pruritus is the leading symptom of dermatophytosis. Microsporium canis is one of the predominant dermatophytes causing dermatophytosis. However, the pruritogenic agents and the related molecular mechanisms of the dermatophyte M canis remain poorly understood. In this study, the secretion of the dermatophyte M canis was found to dose-dependently evoke itch in mice. The fungal peptide micasin secreted from M canis was then identified to elicit mouse significant scratching and itching responses. The peptide micasin was further revealed to directly activate mouse dorsal root ganglia neurons to mediate the nonhistaminergic itch. Knockout and antagonistic experiments demonstrated that MRGPRX1/C11/A1 rather than MRGPRX2/b2 activated by micasin contributed to pruritus. The chimeras and single-amino acid variants of MRGPRX1 showed that 3 domains (extracellular loop 3, transmembrane helical domain 3, and transmembrane helical domain 6) and 4 hydrophobic residues (Y99, F237, L240, and W241) of MRGPRX1 played the key role in micasin-triggered MRGPRX1 activation. Our study sheds light on the dermatophytosis-associated pruritus and may provide potential therapeutic targets and strategies against pruritus caused by dermatophytes.

Asymptomatic colonization of stray dogs and domestic cats with Trichophyton mentagrophytes II* in Northern Iran

BACKGROUND

Despite changes in the epidemiology of dermatophyte infections, the incidence of fungal infections associated with Trichophyton species still remains high among dogs and cats. The objective of the present study was to isolate and characterize dermatophytes from dogs and cats in Iran.

METHOD

From December 2022 to May 2023, skin and hair samples were collected from symptomatic and asymptomatic cats and dogs in Mazandaran, a northern province of Iran. The samples were then inoculated into Mycosel™ Agar. Dermatophyte isolates were identified by sequencing the internal transcribed spacer region. Antifungal susceptibility tests were conducted using the Clinical and Laboratory Standards Institute (CLSI-M38-A3).

RESULT

Of the 250 samples collected (from 200 dogs and 50 cats), 20 (from 19 dogs and one cat) (8.0 %) were positive for dermatophyte growth. Based on sequence and phylogenetic analysis, all isolates belonged to T. mentagrophytes II*. Of these positive samples, 14 (70.0 %), 3 (15.0 %), 2 (10.0 %), and 1 (2.0 %) were isolated from asymptomatic stray dogs, symptomatic stray dogs, symptomatic domestic dogs, and symptomatic cats, respectively. Luliconazole and terbinafine displayed potent activity against all T. mentagrophytes isolates, with Minimum inhibitory concentration (MIC) values of 0.016 µg/ml. Miconazole and griseofulvin demonstrated higher MIC (1 and 8 µg/ml).

CONCLUSION

The present study indicated that T. mentagrophytes II* asymptomatic carriage is frequent in stray dogs in Iran. The potential risk to public health needs to be evaluated However, T. mentagrophytes genotype VIII, considered as an endemic and emerging human pathogenic clone in several countries, was not detected during the present survey.

Enhancing community health: Veterinary services for underserved areas in Costa Rica with a One Health Approach

In underserved areas of Costa Rica, community veterinary services aim to provide comprehensive care for companion animals, covering preventive, therapeutic, and surgical medicine. Emphasizing a One Health approach, our model focuses on animal welfare, health, and public well-being in vulnerable regions. The project's goal is to ensure the overall well-being of animals, people, and the environment by collaboratively addressing animal health issues and recognizing their interconnected impact on optimal health. Limited resources in underprivileged areas, including restricted access to veterinary care for pets, pose challenges to overall health. Despite its global health benefits, the absence of companion animal veterinary care in these regions has been largely overlooked. Our One Health approach not only addresses animal health but also has a significant impact on human and environmental health, economies, and social factors. This innovative strategy is a pioneering effort to tackle complex health issues in Costa Rica.

Itraconazole in human medicine and veterinary practice

Diagnosis and management of fungal infections are challenging in both animals and humans, especially in immunologically weakened hosts. Due to its broad spectrum and safety profile when compared to other antifungals, itraconazole (ITZ) has been widely used in the treatment and prophylaxis of fungal infections, both in human and veterinary medicine. The dose and duration of management depend on factors such as the type of fungal pathogen, the site of infection, sensitivity to ITZ, chronic stages of the disease, the health status of the hosts, pharmacological interactions with other medications and the therapeutic protocol used. In veterinary practice, ITZ doses generally vary between 3 mg/kg and 50 mg/kg, once or twice a day. In humans, doses usually vary between 100 and 400 mg/day. As human and veterinary fungal infections are increasingly associated, and ITZ is one of the main medications used, this review addresses relevant aspects related to the use of this drug in both clinics, including case reports and different clinical aspects available in the literature.

PDE4D and miR-203 are promising biomarkers for canine atopic dermatitis

BACKGROUND

Canine atopic dermatitis (CAD) is a common genetically predisposed, inflammatory, and pruritic skin disorder that affects dogs globally. To date, there are no specific biomarkers available to diagnose CAD, and the current diagnosis is based on a combination of criteria including patient history, clinical signs, and exclusion of other relevant differential diagnoses.

METHODS AND RESULTS

We examined the gene expression of phosphodiesterase 4D (PDE4D) in peripheral blood mononuclear cells (PBMCs), as well as miR-203 and miR-483 in plasma, in three groups: healthy dogs, CAD dogs, and other inflammatory pruritic skin diseases (OIPSD) such as pemphigus foliaceus, scabies, cutaneous lymphoma, and dermatophytosis. Our results showed that PDE4D gene expression in the CAD group is statistically higher compared to those in the healthy and OIPSD groups, suggesting PDE4D may be a specific marker for CAD. Nevertheless, no correlation was found between PDE4D gene expression levels and the lesion severity gauged by CAD severity index-4 (CADESI-4). We also showed that miR-203 is a generic marker for clinical dermatitis and differentiates both CAD and OIPSD inflammatory conditions from healthy controls.

CONCLUSIONS

We show that PDE4D is a potential marker to differentiate CAD from non-atopic healthy and OIPSD while miR-203 may be a potential marker for general dermatologic inflammation. Future study of PDE4D and miR-203 on a larger scale is warranted.

Pharmaceutical Compounding in Veterinary Medicine: Suspension of Itraconazole

Itraconazole is a drug used in veterinary medicine for the treatment of different varieties of dermatophytosis at doses between 3-5 mg/kg/day in cats. Nevertheless, in Spain, it is only available in the market as a 52 mL suspension at 10 mg/mL. The lack of alternative formulations, which provide sufficient formulation to cover the treatment of large animals or allow the treatment of a group of them, can be overcome with compounding. For this purpose, it has to be considered that itraconazole is a weak base, class II compound, according to the Biopharmaceutics Classification System, that can precipitate when reaching the duodenum. The aim of this work is to develop alternative oral formulations of itraconazole for the treatment of dermatophytosis. Several oral compounds of itraconazole were prepared and compared, in terms of dissolution rate, permeability, and stability, in order to provide alternatives to the medicine commercialized. The most promising formulation contained hydroxypropyl methylcellulose and β-cyclodextrin. This combination of excipients was capable of dissolving the same concentration as the reference product and delaying the precipitation of itraconazole upon leaving the stomach. Moreover, the intestinal permeability of itraconazole was increased more than two-fold.

Superficial Zoonotic Mycoses in Humans Associated with Cats

Dermatophytosis is a superficial fungal skin infection common in humans around the world and is one of the many zoonotic skin diseases that cat owners are at risk of contracting. This retrospective study was conducted based on a detailed analysis of the results of mycological examination and medical documentation of 56 patients diagnosed with cat-to-human dermatophytoses from January 2017 to July 2022. Zoonotic mycoses were diagnosed more frequently in young people and women. In children, lesions most often occurred in the scalp area, and in adults, in the glabrous skin area. Skin infections caused by Microsporum canis (M. canis) prevailed and were confirmed in 47 patients (83.9%). Trichophyton mentagrophytes (T. mentagrophytes) was found in nine (16.1%) patients. M. canis predominantly caused infections of the scalp, followed by lower limb infections. Hairy scalps were almost exclusively involved in children. The odds of diagnosing M. canis infection compared to T. mentagrophytes infection was significantly higher in the head than in other regions, especially among children. The positive predictive value of a direct macroscopic examination was relatively low.

Unravelling Childhood Tinea Capitis: A Multi-Dimensional Investigation Using Dermoscopy, Scanning Electron Microscopy and Mass Spectrometry

Tinea capitis, a common cutaneous fungal infection, shows an increasing prevalence with the increasing number of pets. We present tinea capitis in a 4-year-old girl presenting without typical symptoms such as alopecia or hair breakage. After a comprehensive evaluation including dermoscopy, Wood's light, direct KOH fluorescent staining, scanning electron microscopy, fungal culture and mass spectrometry analysis, a diagnosis of tinea capitis infected Microsporum canis carried by domestic cats was made. We preliminarily explored the two modes of hair erosion by tinea capitis fungi and analyzed the possibility of the feature in this case. This case highlights the importance of accurate diagnosis and appropriate therapeutic intervention in cases of paediatric tinea capitis, particularly in households with resident pets.

Methicillin-resistant coagulase-positive staphylococci in new, middle-aged, and old veterinary hospitals in southern Thailand: A preliminary study

Background and Aim

Methicillin-resistant coagulase-positive staphylococci (MRCoPS) cause pyoderma, dermatitis, and nosocomial infection. Numerous factors, including indiscriminate antimicrobial use (AMU) in veterinary medicine, cleaning practices, and AMU in hospitals, contribute to MRCoPS. However, the relationship between hospital age and MRCoPS has not yet been investigated. This study aimed to estimate the prevalence of MRCoPS in the treatment and operation rooms of new, middle-aged, and old veterinary hospitals.

Materials and Methods

Samples were collected from small animal hospitals in Surat Thani, Nakhon Si Thammarat, and Songkhla in Thailand. Hospitals were defined as those that had been in operation for 5 years (new, n = 5), 5-15 years (middle-aged, n = 6), or >15 years (old, n = 3). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to identify 280 samples, and duplex polymerase chain reaction was used to identify resistance genes (mecA and blaZ). The VITEK2® automated system was then used to determine the minimum inhibitory concentration.

Results

A total of 57 Staphylococcus species were identified and classified as coagulase-positive staphylococci (CoPS) (22/57, 38.60%) or coagulase-negative staphylococci (35/57, 61.40%), respectively. Nine of the 22 CoPS (40.90%) harbored the mecA gene, and 21 isolates (95.45%) harbored the blaZ gene. Interestingly, more MRCoPS was found in new hospitals (six isolates) than in middle-aged (one isolate) and old hospitals (two isolates), although there was no statistically significant difference in the presence of MRCoPS across new, middle-aged, and old veterinary hospitals (p = 0.095), Kruskal-Wallis test. There is a need for further detailed studies, including an increase in the number of hospitals in various locations.

Conclusion

MRCoPS is a nosocomial pathogen that causes zoonotic and recurrent infections in veterinary hospitals. The prevalence of MRCoPS tended to be higher in new hospitals. Areas with heavy animal contact, such as hospital floors, are areas of particular concern, and cleaning/disinfection of these areas must be highlighted in hygiene regimens.

Microbes on Clipper Blades after Use and Disinfection in Small Animal- and Equine Practice

Clipping hair on animals can produce microtraumas of the skin and the dislodgement of microorganisms to the clipper blade. This study evaluates if clipper blades in animal hospitals in Sweden are contaminated with bacteria and/or dermatophytes after disinfection. Eleven clipper blades from three veterinary referral hospitals, including one with a small animal department and an equine department, were sampled for bacteria and dermatophytes. All the hospitals had disinfection routines in accordance with the national recommendations for hygiene in veterinary medicine. The sampled clipper blades were supposed to be disinfected and they were considered to be ready for use by staff. Five sterilized clipper blades were used as controls. The results showed that 64-100% of the disinfected clipper blades, from all three hospitals, were contaminated with bacteria, whereas all the sterilized clipper blades were negative for bacterial growth (p < 0.05). One clipper blade from the equine department was contaminated with dermatophytes. The results indicate that the disinfection routines were not sufficient for removing bacteria from used clipper blades, and that sterilization would be a more reliable way to minimize the risk of contamination.

Subtilisin 3 production from Microsporum canis is independent of keratin substrate availability

Dermatophytes are highly infectious fungi that cause superficial infections in keratinized tissues in humans and animals. This group of fungi is defined by their ability to digest keratin and encompasses a wide range of species. We investigated a critical adhesion protein, subtilisin 3, utilized by Microsporum canis during initial stages of infection, analyzing its production and expression under varying growth conditions. Additionally, as this protein must be expressed and produced for dermatophyte infections to occur, we developed and optimized a diagnostic antibody assay targeting this protein. Subtilisin 3 levels were increased in culture when grown in baffled flasks and supplemented with either l-cysteine or cat hair. As subtilisin 3 was also produced in cultures not supplemented with keratin or cysteine, this study demonstrated that subtilisin 3 production is not reliant on the presence of keratin or its derivatives. These findings could help direct future metabolic studies of dermatophytes, particularly during the adherence phase of infections.

The inhibitory effects of zinc oxide nanoparticles on clinical isolates of Microsporum canis in dogs and cats

INTRODUCTION

Microsporum canis is the most common dermatophyte infecting pets and their owners, and its long duration of treatment and increasing rate of drug resistance have caused the attention of researchers to be directed towards the use of nanoparticles and new alternatives for treatment. This study investigated the antifungal effects of zinc oxide (ZnO) nanoparticles on clinical isolates of M. canis in dogs and cats and subtilisin 1 (SUB1) gene expression.

MATERIALS AND METHODS

Zinc oxide nanoparticles were prepared using the wet chemical method at a concentration of 4000 ppm. Its antifungal potential was evaluated at concentrations of 62.5-4000 ppm by disk diffusion and microdilution methods against 10 isolates of M. canis. The effect of this product on SUB1 gene expression was investigated by quantitative real-time PCR method.

RESULTS

The results of the disk diffusion test showed that the highest inhibitory diameter was at the highest concentration of ZnO nanoparticles (34 mm), and the inhibitory zone was observed in dilutions up to 250 ppm. The minimum inhibitory concentration (MIC) of ZnO nanoparticles was between 250 and 500 ppm, and the minimum fungicidal concentration was between 500 and 1000 ppm. There was a significant reduction in SUB1 gene expression in sub-MIC concentration (125-250 ppm) (p < 0.05).

CONCLUSION

This study showed that ZnO nanoparticles have a concentration-dependent inhibitory effect on M. canis. Moreover, ZnO nanoparticles could decrease the expression of SUB1, an enzyme involved in fungi adhesion to the epidermis. Nevertheless, more studies must be done in the future to determine the possible side effects and safety of ZnO nanoparticles along with their efficacy in vivo.

Fungal diversity and drug susceptibility of the oral mycobiome of domestic dogs

The purpose of this study was to characterize the variety and diversity of the oral mycobiome of domestic dogs and to identify the commensal and potentially pathogenic fungi present. Two hundred fifty-one buccal swabs from domestic dogs were obtained and struck onto a chromogenic fungal growth medium that distinguishes between fungal species based on colony color and morphology. After isolating and harvesting single colonies, genomic DNA was extracted from pure cultures. PCR was used to amplify a fungal-specific variable rDNA region of the genome, which was then sent for sequencing. Sequencing results were input into the NCBI BLAST database to identify individual components of the oral mycobiome of tested dogs. Of the 251 dogs swabbed, 73 had cultivable fungi present and 10 dogs had multiple fungal species isolated. Although the dogs did not show signs of oral infections at the time, we did find fungal species that cause pathogenicity in animals and humans. Among fungal isolates, Malassezia pachydermatis and species from the genus Candida were predominant. Following fungal isolate identification, antifungal drug susceptibility tests were performed on each isolate toward the medically important antifungal drugs including fluconazole, ketoconazole, and terbinafine. Drug susceptibility test results indicated that a large number of isolates had high MIC values for all three drugs. Exploring the oral mycobiome of dogs, as well as the corresponding drug susceptibility profiles, can have important implications for canine dental hygiene, health, and medical treatment. Identifying the microorganisms within the canine mouth can illustrate a common pathway for fungal pathogens of One Health concern to spread from our canine companions to humans.

Wild bee and pollen microbiomes across an urban-rural divide

Wild pollinators and their microbiota are sensitive to land use changes from anthropogenic activities that disrupt landscape and environmental features. As urbanization and agriculture affect bee habitats, human-led disturbances are driving changes in bee microbiomes, potentially leading to dysbiosis detrimental to bee fitness. This study examines the bacterial, fungal, and plant compositions of the small carpenter bee, Ceratina calcarata, and its pollen provisions across an urban-rural divide. We performed metabarcoding of C. calcarata and provisions in Toronto by targeting the 16S rRNA, ITS, and rbcL regions. Despite similar plant composition and diversity across bees and their provisions, there was a greater microbial diversity in pollen provisions than in bees. By characterizing the differences in land use, climate, and pesticide residues that differentiate urban and rural landscapes, we find that urban areas support elevated levels of microbial diversity and more complex networks between microbes and plants than rural areas. However, urban areas may lead to lower relative abundances of known beneficial symbionts and increased levels of pathogens, such as Ascosphaera and Alternaria fungi. Further, rural pollen provisions indicate elevated pesticide residues that may dysregulate symbiosis. As anthropogenic activities continue to alter land use, ever changing environments threaten microbiota crucial in maintaining bee health.

Survey of Sensitization to Common Fungi in an Allergic Dog Population: The Need for Further Focus on Sensitization and Allergy to Fungi in Veterinary Medicine

Most fungal species are commensals and non-pathogenic to plants, humans, or animals. However, several species of the Alternaria, Aspergillus, Trichophyton, and Microsporum genera are common causes of disease, even for immunocompetent individuals. Besides mucosal damage, fungi may contribute to a skin barrier impairment, favoring sensitization and allergy development. A total of 68 allergic dogs were selected from a veterinary dermatology and allergy outpatient consultation for conditions related to both Malassezia overgrowth and other fungal complications. The allergy diagnosis was made through anamnesis and current clinical criteria, with the involved allergenic species being identified by intradermal tests (IDTs) and allergen-specific immunoglobulin E (sIgE) determination in serum. Dermatophagoides farinae, Dactylis glomerata, and Malassezia pachydermatis showed as the higher sensitization species from house dust mites, grass pollen, and fungi, respectively. Significant correlations at p < 0.05 were found between sensitization to Dactylis glomerata and Phleum pratense grass pollens, Dermatophagoides farinae and Dermatophagoides pteronyssinus, Acarus siro, Tyrophagus putrescentiae, and Lepidoglyphus destructor dust/storage mites, and between fungi like Aspergillus mix and Penicillium or Alternaria alternata. A significant correlation was also found between sensitization to the Aspergillus mix and D. farinae, D. pteronyssinus, or A. siro. Rather severe dermatitis was observed when a positive IDT to Malassezia pachydermatis was found, regardless of the detection of circulating sIgE, allowing us to consider the usefulness of both the IDT and the sIgE for a systematic diagnosis of allergy to fungi.

Hyphae, pseudohyphae, yeasts, spherules, spores, and more: A review on the morphology and pathology of fungal and oomycete infections in the skin of domestic animals

Fungi are among the most common infectious agents affecting the skin of animals. The skin can serve as a port of entry for fungal infections, which can eventually become disseminated. In some regions of the world, oomycetes, such as Pythium and Lagenidium, are also responsible for a significant number of severe cutaneous infections. Histologic evaluation of fungal morphology, including size, shape, septation, branching, and budding characteristics, combined with the distribution of inflammatory infiltrates within different skin layers can potentially identify etiologic agents, guiding selection of antifungals and additional diagnostics. Fungal infections of the skin surface are typically caused by Malassezia and rarely Candida, with opportunistic fungi also capable of colonizing the skin surface, especially when the barrier is broken. Folliculocentric infections, caused by dermatophytes, result in mild to severe inflammation and can occasionally penetrate deep into the skin. A wide range of fungi, including agents of hyalohyphomycosis, phaeohyphomycosis, and dimorphic fungal infections, as well as oomycetes, result in nodular cutaneous and subcutaneous lesions. With the occasional exception of dimorphic fungi, fungal speciation often requires cultures performed on fresh tissues. However, molecular techniques such as pan-fungal polymerase chain reaction on paraffin blocks is becoming an increasingly useful tool to distinguish between cutaneous fungal pathogens. This review focuses on describing the clinical and histologic features of the most common fungal and oomycete infections affecting the skin of animals, divided according to distribution patterns of lesions and fungal or oomycete morphology.

2023 AAHA Management of Allergic Skin Diseases in Dogs and Cats Guidelines

These guidelines present a systematic approach to diagnosis, treatment, and management of allergic skin diseases in dogs and cats. The guidelines describe detailed diagnosis and treatment plans for flea allergy, food allergy, and atopy in dogs and for flea allergy, food allergy, and feline atopic skin syndrome in cats. Management of the allergic patient entails a multimodal approach with frequent and ongoing communication with the client. Obtaining a comprehensive history is crucial for diagnosis and treatment of allergic skin diseases, and the guidelines describe key questions to ask when presented with allergic canine and feline patients. Once a detailed history is obtained, a physical examination should be performed, a minimum dermatologic database collected, and treatment for secondary infection, ectoparasites, and pruritus (where indicated) initiated. The process of diagnosing and managing allergic skin disease can be prolonged and frustrating for clients. The guidelines offer recommendations and tips for client communication and when referral to a dermatologist should be considered, to improve client satisfaction and optimize patient outcomes.

Nannizzia species causing dermatophytosis in cats and dogs: First report of Nannizzia incurvata as an etiological agent in Brazil

Dermatophytosis is a superficial cutaneous infection, most commonly caused by fungal species such as Microsporum canis, Nannizzia gypsea (Microsporum gypseum), and Trichophyton mentagrophytes in dogs and cats. The zoonotic potential of these species is concerning, as companion animals are increasingly close to their owners. Therefore, the objectives of the study were to evaluate the current prevalence of Nannizzia-causing canine and feline dermatophytosis in Curitiba and Metropolitan Region, as well as perform phenotypic and phylogenetic characterizations of these isolates. Thus, 241 skin and fur samples from 163 dogs and 78 cats were analyzed from 2020 to 2021. The samples were obtained from animals of three sources: Veterinary Hospital of the Federal University of Paraná, animal shelters, and private clinics. The diagnosis was performed through phenotypic characterization and sequencing ITS rDNA region. Among 97 positive samples for dermatophytes, Nannizzia was identified in 14 (14.4%) samples, while other dermatophyte genera were found in the remaining 83 (85.6%) samples. Among the canine samples, nine (90%) were N. gypsea, and one (10%) was N. incurvata. Whereas in feline samples, three (75%) were N. gypsea, and one (25%) was N. incurvata. It was concluded that among 97 animals infected with dermatophytes, dogs (24.4%; 10/41) were significantly more affected by Nannizzia than cats (7.1%; 4/56) (P < .05). According to molecular analyses, the ITS rDNA region provided satisfactory results for species-level identification of Nannizzia, confirming the first report of N. incurvata as an etiological agent of canine and feline dermatophytosis in Brazil.

Tinea Capitis in Children Younger than Two Years Old: A Retrospective Study and Treatment Recommendations

BACKGROUND

Tinea capitis (TC) is a dermatophytosis of the scalp and hair, which occurs less common in children younger than two years of age, and the data of TC in this age group are still unknown.

OBJECTIVES

We aimed to reveal the epidemiological, clinical and mycological characteristics of TC in children under two years old.

METHODS

We retrospectively analyzed all reported cases of TC in children in their first two years of life from 1991 to 2022, by searching PubMed, Embase, Web of Science, CNKI, Wanfang and Weipu databases.

RESULTS

A total of 47 articles involving 126 cases of pediatric TC were enrolled in this study. The sex ratio (M/F) was 1.28:1. The age of the children ranged from ten days old to two years old with a median age of three months. The main clinical manifestations were alopecic patches (40 cases, 31.7%) and scaling (39 cases, 31.0%) on the scalp, and 29 infants (23.0%) appeared kerion. The most common sources of contagion were animals (35 cases, 27.78%) and humans (31 cases, 24.60%). The leading pathogens were Microsporidium canis (64 cases, 50.79%), followed by Trichophyton violaceum (13 cases, 10.32%), T. mentagrophytes complex (12 cases, 9.52%) and T. tonsurans (10 cases, 7.94%). Ninety-five children (75.40%) were treated with systemic antifungal drugs and 22 patients (17.46%) were only treated with topical therapy. Except for 10 patients with unknown final prognosis, all the other cases were cured after treatment. There was one child (0.79%) relapsed after treatment with griseofulvin and one case (0.79%) presented with gastrointestinal symptoms from griseofulvin.

CONCLUSION

The principal clinical symptoms of TC in children less than two years old were alopecic patches and scaling. The top four pathogens were M. canis, T. violaceum, T. mentagrophytes complex and T. tonsurans. Oral treatment for pediatric TC had achieved good therapeutic effects, and topical therapy can be an alternative choice.

Are polar extracts and essential oil from Origanum vulgare Linn. (oregano) an alternative against itraconazole-resistant dermatophytes from veterinary cases?

Although the conventional therapy against dermatophytosis is based on antifungal drugs and environmental disinfection, the emergence of itraconazole(ITZ)-resistant dermatophytes has encouraged the search for active compounds, such as Origanum vulgare L. (oregano) essential oil (EO). However, little is known about its effect in polar extracts or the mechanism of action of these extracts and EO. We investigated the antifungal activity of four polar extracts and one EO from oregano against ITZ-susceptible and ITZ-resistant dermatophytes and their action mechanism. Polar extracts were prepared as infusions at 10 (INF10) and 60 (INF60) minutes, decoction (DEC) and hydroalcoholic extract (HAE); EO was purchased. All extracts and itraconazole were tested against Microsporum gypseum, M. canis, M. nanum, Trichophyton mentagrophytes and T. verrucosum isolated from cats, dogs and cattle (n = 28), and humans (n = 2) (M38-A2, CLSI). Among polar extract, DEC stood out as antifungal, followed by INF10 and INF60; HAE was little active. For EO, all isolates were susceptible, including ITZ-resistant dermatophytes. EO was selected for action mechanism assays, and acted in cell wall and plasmatic membrane by complexing with fungal ergosterol. By chromatographic analysis, 4-hydroxibenzoic acid was the most prevalent compound in all polar extracts, followed by syringic acid and caffeic acid; luteolin was present only in HAE. For EO, carvacrol was the major compound (73.9%); followed by γ-terpinene (3.6%) and thymol (3.0%). These findings showed that the extract type of oregano has influenced the antifungal action on dermatophytes, highlight EO and DEC, that are promising as antifungal agent, including against ITZ-resistant dermatophytes.

The feline skin microbiome: interrelationship between health and disease

PRACTICAL RELEVANCE

As with other species, the skin microbiome of cats has been assessed over the past few years utilizing modern technologies. This has resulted in the identification of many more bacterial and fungal organisms compared with what had been recorded historically on the skin in various states of health and disease using culture-based studies. This information is expanding the knowledge of how microbial communities are impacted by various changes in the skin health of cats. More specifically, how these microbial communities change in the face of health and disease, and how various therapeutic interventions affect the cutaneous microbiome, lends a greater understanding of disease pathogenesis and provides a growing area of research for correcting dysbiosis and improving feline skin health.

EVIDENCE BASE

Most studies on the feline skin microbiome thus far have been descriptive in nature. These provide a framework for the next level of investigations on how various states of health and disease impact the products produced by the cutaneous microbiome (ie, the cutaneous metabolome), as well as how targeted interventions may promote the restoration of balance.

AIMS

This review aims to summarize what is currently known about the feline cutaneous microbiome and its clinical implications. The role of the skin microbiome in health and disease, the current state of research in this area and the potential for future studies to produce targeted interventions for cats are a particular focus.

Reliability of using Wood's lamp by shelter personnel to diagnose Microsporum canis in cats

Optimising diagnostic methods in shelters so that they are as economical as possible for the shelter is especially important because shelters often have a significant lack of funds and so usually do not carry out preventive screening of cats. Dermatophyte fungi spread quickly and can infect shelter staff. The aim of our work was to identify the occurrence of Microsporum canis in shelter cats. It aimed to determine the prevalence of M. canis in cats at the selected shelter and compare the efficiency of detection using a Wood's lamp and culturing on Sabouraud's agar. All cats present in the shelter at the time of the study (n = 70) were examined with Wood's lamp and hair sampling followed by subsequent culturing on Sabouraud's agar. Identification of fungi was based on microscopic proof of macroconidia and microconidia. The prevalence of M. canis by diagnosis on Sabouraud's agar was 64.29% of cats, with the help of Wood's lamp 48.57% of cats showed positive fluorescence. The sensitivity of the Wood lamp examination was 71% and the specificity was 92%. Our study suggests that Wood's lamp could be used by trained shelter personnel for the first examination of cats at reception and could significantly reduce the risk of spreading M. canis in shelters.

Zoonotic Dermatoses of Exotic Companion Mammals

Integumentary disorders caused by zoonotic agents are very common in exotic companion mammals. This article provides an understanding of the main zoonotic dermatoses including parasitic, fungal, bacterial, and viral diseases to provide the most updated information on their epidemiology, diagnosis, reported clinical signs, and therapies.

Dermatologic Diseases of Four-Toed Hedgehogs

Dermatologic diseases are frequently diagnosed in the four-toed hedgehog. Common clinical signs include spine loss, scales and crusts, pruritus, alopecia, and masses. Caparinia tripilis, family Psoroptidae, is the most common mite affecting hedgehogs, and is diagnosed via light microscopy. Dermatophytosis from Trichophyton erinacei infection is a common zoonotic dermatologic disease in pet hedgehogs. Diagnosis is through fungal culture. Neoplasia is another major cause of dermatologic diseases in four-toed hedgehogs. The diagnostic approach typically begins with a fine-needle aspirate but often requires a biopsy for a definitive diagnosis.

Ferret Dermatology

Skin diseases commonly affect pet ferrets, with neoplastic, endocrine, and parasitic diseases being the most common. This review includes clinical presentation, diagnostic workup, and treatment of diseases with a dermatologic presentation in ferrets.

Rabbit Dermatology

The majority of rabbit skin disease presentations can be divided into pruritus, alopecia, scaling, and nodules. Some disease will have more than one of these clinical signs. Ectoparasites, bacterial and fungal infections, and neoplasia account for most of the causes seen. Diagnostic tests include skin scraping and cytology, microbial culture, and biopsy. Therapy is dependent on cause. In addition to discussing the various causes and their treatments, important clinical care points are noted.

Blepharitis and Neoplasms of the Canine Eyelid Margin and Skin

Canine eyelid masses (tumors) should include the differential clinical diagnoses of neoplasia and blepharitis. They have many common clinical signs including tumor, alopecia, and hyperemia. Biopsy and histologic examination remains the most effective diagnostic test to establish a confirmed diagnosis and appropriate treatment. Neoplasms are typically benign (tarsal gland adenomas, melanocytomas, and so forth) with the exception of lymphosarcoma. Blepharitis is noted in 2 age groups including dogs aged less than 1.5 years and middle aged to older dogs. Most blepharitis cases will respond to specific therapy once an accurate diagnosis is established.

Diseases associated with feline leukemia virus and feline immunodeficiency virus infection: A retrospective study of 1470 necropsied cats (2010-2020)

Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) are retroviruses affecting cats worldwide, and the prevalence of infection varies considerably according to the geographic area. We retrospectively described FIV- and FeLV-associated diseases in a population of 1470 necropsied cats, of which 396 (26.9%) were infected with FeLV, 199 (13.5%) with FIV, and 134 (9.1%) with FeLV and FIV concomitantly. Cats infected with FeLV (OR 3.4) and co-infected with FeLV and FIV (OR 1.9) were more likely to have neoplasms. The diagnosis of lymphoma and leukemia was higher in cats infected with FeLV (OR 3.9 and 19.4, respectively) and coinfected with FeLV and FIV (OR 1.9 and 19.3, respectively). The odds of diagnosing bacterial diseases were higher in cats coinfected with FeLV and FIV (OR: 2.8), whereas the odds of viral diseases were higher in those infected with FeLV (OR: 2.8), with 2.2 times more diagnoses of feline infectious peritonitis. Neoplastic and infectious diseases in FIV-infected cats did not differ significantly from those in uninfected cats. According to our results, a high prevalence of retroviral infections was observed in southern Brazil, mainly in relation to FeLV. Infected cats were significantly younger than uninfected cats. The main causes of death associated with FeLV infection and FeLV and FIV coinfection were neoplastic and infectious diseases. In contrast, FIV infection was not associated with any specific condition.

Bovine ringworm - Detection of Trichophyton verrucosum by SYBR-Green real-time PCR

Trichophyton verrucosum is the most commonly dermatophyte involved in cattle ringworm. This work reported a case of bovine dermatophytosis due to Trichophyton verrucosum detected from the clinical sample by SYBR-Green real-time PCR. The strategy was based on the DNA extraction directly from the infected hair followed by real-time PCR and melting-point analysis. A faster and differential diagnosis was observed when compared to the conventional mycological methodology for detection and identification of Trichophyton verrucosum.

Effects of Coleus amboinicus L. Essential Oil and Ethanolic Extracts on Planktonic Cells and Biofilm Formation of Microsporum canis Isolated from Feline Dermatophytosis

Microsporum canis is an important zoonotic fungus that causes dermatophytosis in domestic animals and their owners. Domestic cats are the primary reservoir for M. canis. Antifungal drugs frequently produce adverse effects on the host animal, increasing the demand for novel alternative treatments derived from nature. We evaluated the antifungal activity of Coleus amboinicus essential oil (CEO) and ethanolic extracts (CEE) against M. canis in planktonic and biofilm growth. Twelve clinical isolates of M. canis were identified in feline dermatophyte samples. Using GC-MS, 18 compounds were identified in CEO, with carvacrol being the major constituent. HPLC analysis of CEE revealed that it contained rosmarinic acid, apigenin, and caffeic acid. The planktonic growth of all M. canis isolates was inhibited by C. amboinicus extracts. The minimum inhibitory concentration at which ≥50% of the isolates were inhibited (MIC₅₀) was 128 µg/mL (32-256 µg/mL) for both CEO and CEE. The MIC₉₀ values of CEO and CEE were 128 and 256 µg/mL, respectively. CEO at MIC (128 µg/mL) and 2× MIC (256 µg/mL) significantly inhibited the biofilm formation of weak, moderate, and strong biofilm-producing M. canis. CEE at 2× MIC (256 µg/mL) significantly inhibited the biofilm formation of all isolates. Overall, C. amboinicus extracts inhibited planktonic growth and exhibited a significant antibiofilm effect against M. canis. Thus, C. amboinicus is a potential source of natural antifungal compounds.

Reproductive Management in Catteries: Optimising health and wellbeing through veterinarian-breeder collaboration

PRACTICAL RELEVANCE

Many veterinarians - even those engaged in small animal reproduction - are uncomfortable with taking care of cat breeders or being in charge of catteries. Likely reasons for this are that feline reproduction is largely under-represented in undergraduate and graduate reproduction teaching, as well as in postgraduate education and science, whereas cat breeders themselves are often well informed and actively share knowledge with other cat breeders via the internet and social media.

CLINICAL CHALLENGES

A variety of problems can exist within a cattery, and collaboration between veterinarian and breeder to solve these is ultimately beneficial for the breeder, for the veterinarian, and for the health and wellbeing of the individual cats and of the cattery as a whole.

AIM

This review presents a comprehensive overview of aspects of cattery management that might negatively impact reproduction, including sanitation, hygiene and infectious disease control. It also discusses monitoring of reproductive performance, breeding recommendations, and the diagnostic and therapeutic approach to some common and specific problems.

EQUIPMENT AND TECHNICAL SKILLS

Reproductive management in the cattery requires no specialised equipment, as such. What it does need is an open mind, in terms of seeing how things are done, an open ear, for listening to the breeder, and the veterinarian's clinical skills in palpation, auscultation and, where required, further examination of the animals. Keeping abreast of the latest information on infectious diseases, disinfection and genetics ensures proper advice is provided.

EVIDENCE BASE

Current knowledge of reproductive management in catteries is summarised in order to apply an evidence-based approach, whenever possible. Notwithstanding, much of the information remains empirical.

Current Topics in Dermatophyte Classification and Clinical Diagnosis

Dermatophytes are highly infectious fungi that cause superficial infections in keratinized tissues in humans and animals. This group of fungi is defined by their ability to digest keratin and encompasses a wide range of species. Classification of many of these species has recently changed due to genetic analysis, potentially affecting clinical diagnosis and disease management. In this review, we discuss dermatophyte classification including name changes for medically important species, current and potential diagnostic techniques for detecting dermatophytes, and an in-depth review of Microsporum canis, a prevalent zoonotic dermatophyte. Fungal culture is still considered the “gold standard” for diagnosing dermatophytosis; however, modern molecular assays have overcome the main disadvantages of culture, allowing for tandem use with cultures. Further investigation into novel molecular assays for dermatophytosis is critical, especially for high-density populations where rapid diagnosis is essential for outbreak prevention. A frequently encountered dermatophyte in clinical settings is M. canis, which causes dermatophytosis in humans and cats. M. canis is adapting to its primary host (cats) as one of its mating types (MAT1-2) appears to be going extinct, leading to a loss of sexual reproduction. Investigating M. canis strains around the world can help elucidate the evolutionary trajectory of this fungi.

Rapid and Visual RPA-Cas12a Fluorescence Assay for Accurate Detection of Dermatophytes in Cats and Dogs

Dermatophytosis, an infectious disease caused by several fungi, can affect the hair, nails, and/or superficial layers of the skin and is of global significance. The most common dermatophytes in cats and dogs are Microsporum canis and Trichophyton mentagrophytes. Wood’s lamp examination, microscopic identification, and fungal culture are the conventional clinical diagnostic methods, while PCR (Polymerase Chain Reaction) and qPCR (Quantitative PCR) are playing an increasingly important role in the identification of dermatophytes. However, none of these methods could be applied to point-of-care testing (POCT). The recent development of the CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) based diagnostic platform promises a rapid, accurate, and portable diagnostic tool. In this paper, we present a Cas12a-fluorescence assay to detect and differentiate the main dermatophytes in clinical samples with high specificity and sensitivity. The Cas12a-based assay was performed with a combination of recombinase polymerase amplification (RPA). The results could be directly visualized by naked eyes under blue light, and all tested samples were consistent with fungal culture and sequencing results. Compared with traditional methods, the RPA-Cas12a-fluorescence assay requires less time (about 30 min) and less complicated equipment, and the visual changes can be clearly observed with naked eyes, which is suitable for on-site clinical diagnosis.

Important Mycosis of Wildlife: Emphasis on Etiology, Epidemiology, Diagnosis, and Pathology—A Review: PART 2

Wild animals are an important component of the ecosystem, and play a major role in it. However, in recent years, there has been an astronomical increase in the incidence of wildlife mycotic diseases leading to wildlife extermination. It is important to note that most of these mycotic diseases are zoonotic, and since there is a lot of attention given to zoonosis of a bacterial or viral origin in recent times, it is important to look into the mycotic diseases which may have zoonotic potential. Previously, the authors expatiated on some major wildlife mycotic diseases. In this review, we shed light on the etiology, epidemiology, diagnosis, pathogenesis, pathogenicity, macroscopic and microscopic pathology, and hematological and serum biochemical findings of dermatophytosis, coccidioidomycosis, blastomycosis, and sporotrichosis, which are very important mycoses of wildlife.

Genetic Characterization of Microsporum canis Clinical Isolates in the United States

Microsporum canis is the primary agent causing dermatophytosis in cats, and also infects humans, dogs, and other species. Assessment of genetic variation among M. canis isolates in the United States has not been conducted. Further, M. canis mating type and assessment of disease severity associated with genotypic characteristics have not been rigorously evaluated. We therefore isolated M. canis from 191 domestic cats across the US and characterized genotypes by evaluation of ITS sequence, MAT locus, and microsatellite loci analysis. The genes SSU1 and SUB3, which are associated with keratin adhesion and digestion, were sequenced from a subset of isolates to evaluate potential genetic associations with virulence. Analysis of microsatellite makers revealed three M. canis genetic clusters. Both clinic location and disease severity were significant predictors of microsatellite variants. 100% of the M. canis isolates were MAT1-1 mating gene type, indicating that MAT1-2 is very rare or extinct in the US and that asexual reproduction is the dominant form of replication. No genetic variation at SSU1 and SUB3 was observed. These findings pave the way for novel testing modalities for M. canis and provide insights about transmission and ecology of this ubiquitous and relatively uncharacterized agent.

Prevalence and Risk Factors of Zoonotic Dermatophyte Infection in Pet Rabbits in Northern Taiwan

Dermatophytes are the group of keratinophilic fungi that cause superficial cutaneous infection, which traditionally belong to the genera Trichophyton, Microsporum, and Epidermophyton. Dermatophyte infection is not only a threat to the health of small animals, but also an important zoonotic and public health issue because of the potential transmission from animals to humans. Rabbit dermatophytosis is often clinically identified; however, limited information was found in Asia. The aims of this study are to investigate the prevalence and to evaluate the risk factors of dermatophytosis in pet rabbits in Northern Taiwan. Between March 2016 and October 2018, dander samples of pet rabbits were collected for fungal infection examination by Wood’s lamp, microscopic examination (KOH preparation), fungal culture, and PCR assay (molecular identification). Z test and Fisher’s exact test were performed to evaluate the potential risk factors, and logistic regression analysis was then performed to build the model of risk factors related to dermatophyte infection. Of the collected 250 dander samples of pet rabbits, 29 (11.6%) samples were positive for dermatophytes by molecular identification. In those samples, 28 samples were identified as the T. mentagrophytes complex and 1 sample was identified as M. canis. Based on the results of the Firth’s bias reduction logistic analyses, animal source (rabbits purchased from pet shops) and number of rearing rabbits (three rabbits or more) were shown as the main risks for dermatophyte infection in the pet rabbits in Taiwan. The results of the present study elucidate the prevalence of rabbit dermatophyte infection, pathogens, and risk factors in Taiwan, and provide an important reference for the prevention and control of rabbit dermatophytosis.

A retrospective analysis of the concordance of in-house fungal culture and a commercial quantitative PCR from 16 dermatology referral practices across the USA (2018-2019)

BACKGROUND

Commercial quantitative (q)PCR and fungal culture can be used concurrently or individually to test for dermatophytosis with a reported high sensitivity and specificity.

HYPOTHESIS/OBJECTIVES

The aims of this retrospective study were: (i) to evaluate the concordance of a commercial qPCR with in-house fungal culture for the initial diagnosis of dermatophytosis and for monitoring for mycological cure during treatment in dermatology private practice; and (ii) determine the sensitivity and specificity of qPCR overall, (iii) for initial diagnosis and (iv) for treatment monitoring in dogs and cats.

ANIMALS

Four-hundred and twenty-seven client-owned dogs and 188 client-owned cats.

MATERIALS AND METHODS

Retrospective evaluation of electronic medical records from 615 client-owned dogs and cats presented to 16 dermatology referral practices across the USA from 2018 to 2019. Concordance of qPCR with in-house fungal culture and sensitivity and specificity were determined from 667 paired samples.

RESULTS

qPCR agreed with in-house fungal culture in 63 of 85 positive tests and 571 of 582 negative tests, with an overall sensitivity and specificity of 74.1% [95% confidence interval (CI) 63.5-83.0] and 98.1% (95%CI 96.6-99.0), respectively. qPCR sensitivity and specificity for the initial diagnosis of dermatophytosis and for treatment monitoring were 72.4% (95%CI 59.1-83.3) and 98.7% (95%CI 97.3-99.5), and 77.8% (95%CI 57.7-91.4) and 92.0% (95%CI 80.1-97.8), respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

Compared to in-house fungal culture, qPCR was less sensitive and more specific than reported previously. These findings suggest that a diagnosis of dermatophytosis and determining mycological cure should continue to be based on a combination of complementary diagnostic tests.

Laboratory Diagnosis and In Vitro Antifungal Susceptibility of Trichophyton quinckeanum from Human Zoonoses and Cats

The “One Health” concept increasingly demonstrates the global spread of pathogenic (also eukaryotic) microorganisms and their zoonotic potential. Dermatophytes can cause superficial mycoses in humans and animals. Furthermore, the number of transmissions from asymptomatic carriers to humans has been on the rise over the last few years. This study was focused on the detailed characterisation of clinical isolates of Trichophyton quinckeanum with epidemiological analyses and characterisation of their in vitro antifungal susceptibility patterns. The isolated dermatophytes were identified with a combination of conventional and molecular methods. In turn, their susceptibility in vitro was tested according to the Clinical and Laboratory Standards Institute (CLSI) M38 ed.3 protocol. A total of 36 strains were isolated, with 21 cases of T. quinckeanum zoonoses resulting from direct contact with symptomatic cats (58.3%). The other 15 strains (41.7%) were isolated simultaneously from healthy cats and their owners. All strains showed high susceptibility to allylamine, pyridinone, and phenyl morpholine derivatives but were resistant to fluconazole and ketoconazole. In conclusion, our study shows the frequency of zoonoses contracted from asymptomatic cats. Moreover, the antifungal susceptibility profiles indicate the serious risk posed to animal owners by resistant strains of T. quinckeanum, which are often responsible for recalcitrant-to-treatment cases.

Tinea capitis with multiple isolates: The interaction of nature, animal and child

Tinea capitis is an infection of the scalp and hair commonly seen in the pediatric population. Detection of multiple dermatophytes is unusual, and true mixed infections have been rarely reported. Herein, we describe an 8-year-old girl with tinea capitis revealing three different dermatophyte isolates that highlight the clinical challenge posed by this phenomenon.

Allergy to Fungi in Veterinary Medicine: Alternaria, Dermatophytes and Malassezia Pay the Bill!

The fungal kingdom comprises ubiquitous forms of life with 1.5 billion years, mostly phytopathogenic and commensals for humans and animals. However, in the presence of immune disorders, fungi may cause disease by intoxicating, infecting or sensitizing with allergy. Species from the genera Alternaria, Aspergillus and Malassezia, as well as dermatophytes from the genera Microsporum, Trichophyton and Epidermophyton, are the most commonly implicated in veterinary medicine. Alternaria and Malassezia stand as the most commonly associated with either allergy or infection in animals, immediately followed by Aspergillus, while dermatophytes are usually associated with the ringworm skin infection. By aiming at the relevance of fungi in veterinary allergy it was concluded that further research is still needed, especially in the veterinary field.

An ancient haplotype containing antimicrobial peptide gene variants is associated with severe fungal skin disease in Persian cats

Dermatophytosis, also known as ringworm, is a contagious fungal skin disease affecting humans and animals worldwide. Persian cats exhibit severe forms of the disease more commonly than other breeds of cat, including other long-haired breeds. Certain types of severe dermatophytosis in humans are reportedly caused by monogenic inborn errors of immunity. The goal of this study was to identify genetic variants in Persian cats contributing to the phenotype of severe dermatophytosis. Whole-genome sequencing of case and control Persian cats followed by a genome-wide association study identified a highly divergent, disease-associated haplotype on chromosome F1 containing the S100 family of genes. S100 calcium binding protein A9 (S100A9), which encodes a subunit of the antimicrobial heterodimer known as calprotectin, contained 13 nonsynonymous variants between cases and controls. Evolutionary analysis of S100A9 haplotypes comparing cases, controls, and wild felids suggested the divergent disease-associated haplotype was likely introgressed into the domestic cat lineage and maintained via balancing selection. We demonstrated marked upregulation of calprotectin expression in the feline epidermis during dermatophytosis, suggesting involvement in disease pathogenesis. Given this divergent allele has been maintained in domestic cat and wildcat populations, this haplotype may have beneficial effects against other pathogens. The pathogen specificity of this altered protein should be investigated before attempting to reduce the allele frequency in the Persian cat breed. Further work is needed to clarify if severe Persian dermatophytosis is a monogenic disease or if hidden disease-susceptibility loci remain to be discovered. Consideration should be given to engineering antimicrobial peptides such as calprotectin for topical treatment of dermatophytosis in humans and animals.

Fungal skin infections known as ringworm or dermatophytosis affect billions of humans and animals worldwide. Normally the disease is self-limiting in affected individuals. The Persian cat breed is a popular breed known for its long hair coat and short nose as well as its propensity to develop severe, chronic dermatophytosis. By examining the genomes of Persian cats, we discovered that a specific region of DNA is highly altered between cats with and without severe dermatophytosis. The DNA sequence in this region is particularly divergent within a cluster of genes involved in immune defense against pathogens. Notably, alterations to the DNA sequence cause several changes in the antimicrobial protein known as calprotectin, which defends against pathogens in the skin of cats. Persian cats with severe dermatophytosis have a version of calprotectin similar to a version maintained by certain desert-dwelling wild felids such as sand cats and Asiatic wildcats. Therefore, we think this version of the protein is beneficial in some environments or against certain pathogens but not against the fungus that causes ringworm in cats. Our findings suggest changes to calprotectin may affect pathogen specificity and engineered calprotectin could be considered as a novel therapy for dermatophytosis in humans and animals.