The role of pacas of captivity as a potential reservoir of zoonotic fungi in Acre, Western Amazon, Brazil / O papel de pacas de cativeiro como potencial reservatório de fungos zoonóticos no Acre, Amazônia Ocidental, Brasil

Wild animals can be natural reservoirs of different microorganisms, essential for monitoring these pathogens for the generation of knowledge and creation of tools aimed at programs for the prevention and control of infectious diseases, including zoonoses. The objective was to report the fungal diversity in the skin of pacas in captivity in Acre, Western Amazon, Brazil. Twenty-six animals were evaluated, from which skin samples were collected by superficial scraping, hair avulsion, and sterile plastic brush. The samples were seeded on Mycosel agar, and the phenotypic characteristics of the colonies were analyzed. In 80.8% of the samples, different fungi were isolated, from the genera Candida, Microsporum,and Trichophyton, among others. This is the first description of the identification of fungi in the skin of pacas and suggests that these animals can be considered essential reservoirs of saprophytic or pathogenic microorganisms with zoonotic potential in the Western Amazon.(AU)

Animais silvestres podem ser reservatórios naturais de diferentes microrganismos, sendo fundamental o monitoramento destes patógenos para a geração de conhecimento e criação de ferramentas direcionadas a programas de prevenção e controle de enfermidades infecciosas, incluindo as zoonoses. Assim, objetivou-se relatar a diversidade fúngica da pele de pacas criadas em cativeiro no Acre, Amazônia Ocidental, Brasil. Foram avaliados 26 animais, dos quais amostras cutâneas foram colhidas por raspagem superficial, avulsão pilosa e escova plástica estéril. As amostras foram semeadas em ágar Mycosel e as características fenotípicas das colônias foram analisadas. Em 80,8% das amostras houve isolamento de diferentes fungos, dos gêneros Candida, Microsporum e Trichophyton, dentre outros. Esta é a primeira descrição da identificação de fungos na pele de pacas e sugere que estes animais podem ser considerados importantes reservatórios de microrganismos saprófitas ou patogênicos, de potencial zoonótico, na Amazônia Ocidental.(AU)

Clinical and epidemiological characteristics of tinea capitis in northern Taiwan during 2014-2019: An unusual bimodal distribution of patients and comparison of paediatric and adult cases.

Tinea capitis (TC) mainly occurs in children, and related studies in adults are rare. We aimed to investigate the current epidemiological, clinical and mycological characteristics of TC and to compare adult and paediatric patients in northern Taiwan. We conducted a retrospective study at Chang Gung Memorial Hospital, Linkou Branch, from 2014 to 2019. The dataset included age, sex, records of underlying diseases, animal contact history, frequent hair salon visits, clinical patterns, treatment and outcome via chart or phone call reviews. The average ages of 72 children and 104 adults recruited were 6.0 and 74.0 years, respectively. A female predominance was noted in both groups, and the ratio of females was significantly higher in adults (94.2% vs 59.7%, P < .0001). Microsporum canis (76.4%) and Trichophyton mentagrophytes (11.1%) in children, and M. canis (49.0%) and T. violaceum (31.7%) in adults were the most common pathogens. Adults were more likely to be infected with T. violaceum (OR = 10.14, 95% CI = 2.04-50.26) than children. In contrast, adults were less likely to be infected with M. canis than children (OR = 0.31, 95% CI = 0.11-0.90). Furthermore, adults visited hair salons more, had less animal contact and were more immunosuppressed than children. TC is not unusual in the adult population. Dermatologists are advised to realise risk factors such as immunosuppression and regular hair salon visit in adult TC.

Comparative Analysis of Putative Virulence-Associated Factors of Microsporum canis Isolates from Human and Animal Patients.

Microsporum canis is a zoophilic dermatophyte and the most common fungus isolated from dogs and cats worldwide. To invade skin, this pathogen uses different enzymes, which may be associated with virulence, that contribute to the fungal pathogenicity. The aim of this study is to compare the expression of enzymes that may be associated with virulence, and thermotolerance of M. canis strains isolated from dogs, cats, and humans. The in vitro expression of the enzymes keratinase, catalase, urease, hemolysin, and aspartic protease was evaluated in 52 M. canis strains recently isolated from 14 human patients, 12 dogs, 15 symptomatic, and 11 asymptomatic cats. In addition, thermotolerance was assessed by comparative analysis of fungal growth at 25 °C and 35 °C. Keratinase activity was low in 34 and moderate in 18 strains. Aspartic-protease activity was low in 7, moderate in 33, and high in 12 strains. Hemolysin activity was low in 44 and moderate in 8 strains. All strains were classified as low producers of catalase. All but three strains produced urease in vitro, with a broad range of activity. The strains presented in vitro growth at the two studied temperatures were classified as presenting low (36.5%), medium (44.3%), or high (19.2%) thermotolerance. There was no statistically significant difference in the new putative virulence-associated factors studied among the different hosts, which suggests that they may have a similar role on human, cat, and dog infection. Also, no difference was observed between strains isolated from symptomatic and asymptomatic cats. This suggests that these factors have a limited impact on the fate of feline dermatophytosis caused by M. canis.

Usefulness of Wood's Lamp for the Diagnosis and Treatment Follow-up of Onychomycosis.

Wood's lamp was demonstrated to be useful in three cases of dermatophytoma treated during clinical dermatological practice. Clinical signs of onychomycosis are longitudinal yellow and white striae on the nail plate and are diagnosed by KOH direct microscopic examination. For its treatment, surgical debridement is recommended. Usefulness of the Wood's lamp for diagnosis of tinea capitis caused by Microsporum canis is standard. In the first and second cases, we used Wood's lamp (Woody™) to make a clear margin for debridement of onychomycosis. In the third case, onychomycosis was unsuccessfully treated using topical 5% luliconazole nail solution for 1 year and 10 months with yellow nail discoloration. Under Wood's lamp, we were able to distinguish luliconazole crystal staining from onychomycosis. This method is simple and quick, and useful for nail observation in dermatology clinics.

Adult tinea capitis in China: A retrospective analysis from 2000 to 2019.

BACKGROUND: Tinea capitis (TC) is an infection of the scalp hair due to dermatophytes. Most commonly seen in prepubescent children, but data of adults tinea capitis (ATC) in China mainland are limited. OBJECTIVES: We aimed to evaluate epidemiological, clinical and mycological characteristics of ATC in China from 2000 to 2019. METHODS: We retrospectively analysed all ATC reported cases in China mainland, confirmed by mycological examination, by searching PubMed, Wanfang, Weipu and CNKI database. RESULTS: In sum, 40 papers involving 269 clinical cases were included. The average morbidity of ATC was calculated as 9.04% after standardisation. The sex ratio is 1:5.2 (31 male, 163 female); 76 people between 18 and 44 age level and 137 people between 45 and 89 age level were diagnosed as ATC. Culture or ITS sequencing identified Trichophyton violaceum in 70 cases (35.2%), Microsporum canis in 42 cases (21.1%), Trichophyton mentagrophyte in 32 cases (16.1%), Trichophyton rubrum in 23 cases (11.5%), Microsporum gypseum in 18 cases (9.0%), Trichophyton tonsurans in 6 cases (3.0%), Trichophyton schoenleini in 4 cases (2.0%), Epidermophyton floccosum in 2 cases (1.0%), Trichophyton verrucosum and Microsporum ferrugineum in one case (0.5%). ATC was easily to be diagnosed as furfur, seborrhoeic dermatitis (13%) or pustular and dermatocellulitis (11.15%).Six immunocompromised persons were recorded (2.2%). CONCLUSIONS: ATC mainly involves postmenopausal women. Trichophyton violaceum, M canis, T mentagrophyte remain the most common aetiological agent of ATC in China. Trichophyton rubrum own the much higher frequency in ATC than in children. For diversified clinical manifestations, recognising ATC profiles will help clinicians avoid misdiagnosis.

Differential gene expression in HaCaT cells may account for the various clinical presentation caused by anthropophilic and geophilic dermatophytes infections.

BACKGROUND: Despite the worldwide prevalence of dermatophyte infections, only a few genes are reported to be related to dermatophyte infections. In addition, the mechanism by which different ecological dermatophytes infection leads to varying intensity of inflammation remains unclear. OBJECTIVES: To investigate the mechanism of varying intensity of skin inflammation caused by different ecological dermatophytes infection. METHODS: We infected HaCaT cells with anthropophilic and geophilic dermatophytes to mimic various ecological dermatophyte infections. RNA-sequencing (RNA-seq) was employed to identify the change in the gene expression of HaCaT cells. To verify the expression of differentially expressed genes (DEGs), we selected 18 HaCaT cells genes to conduct qPCR experiments. In addition, immunoblotting was conducted to validate key genes from the MAPK signalling pathway. RESULTS: After HaCaT cells were infected with the anthropophilic Trichophyton rubrum (T rubrum) and the geophilic Microsporum gypseum (M gypseum), 118 and 619 differentially expressed genes were identified in HaCaT cells, respectively. These genes may provide a clue as to how keratinocytes respond to anthropophilic and geophilic dermatophytes. We also found that JUN may play a critical role in keratinocytes infected with M gypseum. CONCLUSIONS: Differential gene expression in HaCaT cells may account for the various clinical presentation caused by anthropophilic and geophilic dermatophytes infections. In addition, the intense inflammatory reaction of M gypseum infection may be triggered by activating the JNK-JUN signalling pathway.

FSH1 regulates the phenotype and pathogenicity of the pathogenic dermatophyte Microsporum canis.

Microsporum canis (M. canis) is a common pathogen that causes tinea capitis and is present worldwide. The incidence of M. canis infection, particularly tinea capitis, has been increasing in China. In our previous studies, family of serine hydrolases 1 (FSH1) was identified as a potential virulence factor in tinea capitis infection caused by M. canis. To determine the function of this gene in M. canis, FSH1 was knocked down using double­stranded RNA interference mediated by Agrobacterium tumefaciens. Reverse transcription­quantitative PCR analysis was used to confirm gene knockdown. Loss of FSH1 expression by RNAi resulted in a minor phenotype alteration, but M. canis pathogenicity in guinea pig cutaneous infection was decreased compared with the wild­type strain. To the best of our knowledge, the present study is the first to demonstrate that FSH1 is associated with macroconidia septa formation and is an important contributor to M. canis virulence. These findings may advance the understanding of the function of the FSH1 gene and provide a foundation for future studies on macroconidia septa formation and pathogenicity of M. canis.

Dermatophytosis in dogs and cats - an update. / Dermatophytose bei Hund und Katze ­ ein Update.

Dermatophytosis is a cutaneous infection, caused by several types of keratophilic fungi (dermatophytes). It represents a serious and common contagious skin disease in dogs and cats. The significance of this disease for pet owners is based on the zoonotic potential. The prevalence varies with climate and local dermatophyte infestation. The most common infection in dogs and cats are caused by the genera Microsporum (M.), Nannizzia (N.) or Trichophyton (T.). The aim of this article is to summarise novel taxonomy, diagnosis, and treatment recommendations as well as the recently revised recommendations of the World Association of Veterinary Dermatology.

Endangered Zoonotic Fungal Species from Chicken (Gallus gallus domestics).

Lophophyton gallinae (Microsporum gallinae) is a zoophilic fungus that causes ringworm in chickens and related species, and occasionally in humans. There are 45 human cases worldwide including a Japanese case from Okinawa in 2009. After the finding of the human L. gallinae case, 793 chickens in Japan, including 293 from the mainland and 500 from the Nansei Island areas, were investigated to determine the prevalence of dermatophytes and their related fungal species. The survey was carried out from December 2008 to March 2013. Various dermatophytes and related fungal species were isolated from the studied chickens, with a prevalence of 24.6%. In total, 224 dermatophytes and related species were isolated in the survey. The most commonly isolated species included, in descending order of frequency, Arthroderma multifidum, Aphanoascus terreus, and Chrysosporium spp. Ar. multifidum and Ap. terreus have no record of pathogenicity, and the present isolates of Chrysosporium spp. were not matched to pathogenic Chrysosporium spp. based on the ITS rDNA sequences. Interestingly, an L. gallinae isolate was detected in a male 10-month-old shamo (fighting cock) from the main island. Furthermore, one strain of Arthroderma simii was also isolated as the second record in Japan following that from an imported chimpanzee. Although L. gallinae and Ar. simii are likely to be endemic in our country, the transmission of dermatophytosis from chickens to humans is unlikely to occur because of the reduced chances for citizens to come in contact with chickens due to various factors.

IL-17-Mediated Immunity Controls Skin Infection and T Helper 1 Response during Experimental Microsporum canis Dermatophytosis.

Despite worldwide prevalence of superficial mycoses, the immune response in dermatophytosis has scarcely been investigated. In this study, we developed a model of superficial skin infection in C57BL/6 mice with Microsporum canis, a highly prevalent human pathogen. This model mimics mild inflammatory human dermatophytosis, characterized by neutrophil recruitment and fungal invasion limited to the epidermis and exhibits the establishment of a specific T helper type 17 immune response during infection. By using IL-17RA- or IL-17A/F-deficient mice we showed that, in the absence of a functional IL-17 pathway, M. canis extensively colonizes the epidermis and promotes an exaggerated skin inflammation and a shift to an IFN-γ-mediated (T helper type 1) response. IL-17 signaling was not involved in neutrophil influx to skin or fungal invasion to deeper tissues. Finally, this study shows that skin langerin-expressing cells contribute to the antifungal T helper type 17 response in vivo. In conclusion, these data directly show a dual function of IL-17 cytokines in dermatophytosis by controlling superficial infection and down-modulating a T helper type 1 antifungal response.

Kerion Celsi due to Microsporum canis with a Dermatophytid Reaction.

Microsporum (M.) canis is the most common fungus to cause tinea capitis in Europe, especially in the Mediterranean region and South and Central Europe. Fungal scalp infections caused by M. canis tend to be non-inflammatory. Recently, a growing number of cases of tinea capitis characterized by inflammatory infection caused by M. canis and M. gypseum have been registered. We present a case of highly inflammatory tinea capitis, also known as kerion celsi, caused by M. canis in a 6-year-old-patient. Scalp infections due to M. canis are a growing problem in dermatological practice. Changes in epidemiology, etiology, and clinical patterns of fungal infections due to M. canis are significant. Greater awareness of this problem is needed in order to establish proper diagnosis and successful treatment strategy for these patients.

Remarkable Works and Cases in the History of Medical Mycology in Japan.

Several pathogenic fungi and cases related to Japanese medical mycologists were reviewed. Trichosporon inkin (as Sarcinomyces inkin) was reported as a pathogen of scrotal lesion by Oho in 1921, and Trichosporon asahii was isolated from generalized keratotic lesions in 1922 by Akagi in Japan. They were once included in Trichophyton beigelii, but then based on revision using DNA molecular technology, were returned to their original names.Microsporum ferrugineum was reported by Ota as a causative dermatophyte of tinea capitis in Japan and surrounding areas. It was once classified under the genus Trichophyton, but after the discovery of characteristic rough-walled macroconidia belonging to genus Microsporum, the fungus was again assigned to the original name.

Inibitory effects of linalool on fungal pathogenicity of clinical isolates of Microsporum canis and Microsporum gypseum.

In humans worldwide, Microsporum sp. is a frequent agent of dermatophytsosis. When considering the emergence of resistant fungi and the clinical relevance of dermatophytosis, terpene antifungal activity is of great interest. Linalool is a monoterpene alcohol with pharmacological properties. In this study, antifungal in vitro activity of linalool and ketoconazole (as a positive control) were evaluated against clinical isolates of M. canis and M. gypseum. The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of each drug were determined by broth microdilution. The effects of the drugs (1/2MIC, MIC, 2xMIC) on radial mycelial growth, conidial production and germination were analysed. The effect on the fungal cell membrane (release of intracellular material) was also investigated. Linalool (MIC: 128 µg/mL) and ketoconazole (MIC: 64 µg/mL) were effective in inhibiting all dermatophytes studied. The MFC values of linalool ranged between 128 and 256 µg/mL, whereas ketoconazole showed MFC values of from 64 to 256 µg/mL. Linalool (at MIC and 2xMIC) and ketoconazole (at 1/2MIC, MIC, 2xMIC) inhibited mycelial growth (P < 0.05). The drugs (1/2MIC, MIC, 2xMIC) were also active on conidiogenesis and conidia germination, causing complete inhibition (P < 0.05). Linalool caused leakage of intracellular material. Our study supports the use of linalool as a potential antifungal agent against M. canis and M. gypseum.

Decontamination of carpet exposed to Microsporum canis hairs and spores.

Objectives The objective of this study was to evaluate the efficacy of vacuuming and three carpet cleaning methods for the removal of Microsporum canis spores and hairs from experimentally contaminated carpets. Methods Sterile Berber carpeting was artificially contaminated with naturally infective M canis hairs and spores. Carpet swatches were vacuumed for 10 s, 30 s and 60 s, and then cultured. Three carpet cleaning methods were evaluated on area rugs experimentally contaminated with infective material: a beater brush carpet shampooing, beater brush carpet shampooing post-disinfectant application and hot water extraction. Home cleaning products labeled as having efficacy against Trichophyton species were used in addition to 1% potassium peroxymonosulfate. Carpets were cultured at 24 h, 48 h and 7 days after cleaning. Good efficacy was no detectable spores at post-cleaning culture. Results All pretreatment carpet samples were culture positive for M canis (>300 colony-forming units [cfu]/site). Vacuuming did not decontaminate carpets but did remove intact hairs. Spores were not detected by wipe samples after two washings with an upright beater brush carpet shampooer or pretreatment with a disinfectant prior to carpet shampooing. Carpets cleaned with one hot water extraction technique had a decrease from 300 cfu/site to a mean of 5.5 cfu/site at 24 and 48 h post-cleaning and 2 cfu/site at day 7. The use of disinfectants was associated with odor, even when dry, and permanent discoloration. Hot water extraction cleaning was associated with the fastest drying time and no discoloration. Conclusions and relevance Carpets exposed to M canis can be disinfected via carpet shampooing or hot water extraction cleaning. Vacuuming of carpets is recommended to remove infective hairs. For homes, exposed carpeting can be decontaminated by routine washing with a carpet shampooer (twice) or hot water extraction. Use of pretreatment with a disinfectant is recommended when a high level of overall decontamination is needed in an animal facility with necessary carpeted surfaces (eg, entryway carpet mats).

Pathogenesis of Dermatophytosis: Sensing the Host Tissue.

The genera Trichophyton, Microsporum, and Epidermophyton include filamentous fungi that cause dermatophytosis, a superficial infection of the skin, stratum corneum, nail beds, and hair follicles. The ability of dermatophytes to adhere to these substrates and adapt to the host environment is essential for the establishment of infection. Several fungal enzymes and proteins participate in this adaptive response to the environment and to keratin degradation. Transcription factors such as PacC and Hfs1, as well as heat shock proteins, are involved in sensing and adapting to the acidic pH of the skin in the early stages of fungal-host interaction. During dermatophyte growth, with keratin as the sole carbon source, the extracellular pH shifts from acidic to alkaline. This creates an environment in which most of the known keratinolytic proteases exhibit optimal activity. These events culminate in the establishment and maintenance of the infection, which can be chronic or acute depending on the dermatophyte species. This review focuses on these and other molecular aspects of the dermatophyte-host interaction.

Nódulos fluctuantes en el cuero cabelludo de un niño / Fluctuating nodules on the scalp of a child

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Haemolytic and co-haemolytic (CAMP-like) activity in dermatophytes.

Dermatophytes are some of the most common fungal pathogens in both humans and animals. These fungi release enzymes (e.g., keratinases) that play roles in their pathogenesis. Little is known about their haemolytic and co-haemolytic (CAMP-like) activities; however, in bacteria, these components play significant roles in pathogenesis. This study characterised these two factors in 45 dermatophyte strains (representing the genera Arthroderma, Epidermophyton, Microsporum and Trichophyton) using Columbia agar (CA) supplemented with 5% bovine, ovine and equine erythrocytes. Haemolysis was best observed on CA supplemented with ovine erythrocytes followed by equine and bovine erythrocytes, while CAMP-like reactions occurred using bovine and ovine but not equine erythrocytes. Haemolytic and CAMP-like activities were best observed using ovine and bovine erythrocytes in CA in 44 and 38 strains at 7 and 3 days respectively. Most dermatophytes recovered from both symptomatic and asymptomatic lesions had haemolytic and CAMP-like activities. We suggest that the haemolytic and CAMP-like activities are not correlated with ecological characteristics, isolation sites or clinical manifestations of dermatophytic fungi. We also believe that this study has the potential to contribute to the existing literature on dermatophytes and dermatophyte pathogenesis.

Tinea capitis y dermatoscopia / Tinea capitis and dermatoscopy

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Two cases of dermatophytosis caused by Microsporum gypseum and isolation of Microsporum gypseum from soil in Chigasaki city.

We report two cases of dermatophytosis caused by Microsporum (M.) gypseum. One case was a 59-year-old healthy woman who complained of itchy annular erythema on her right forearm. We isolated M. gypseum from scales on the forearm. The other case was a 73-year-old midwife who had developed infiltrated erythema on her face for 6 months. M. gypseum was isolated from scales of the nose. Both women liked gardening and M. gypseum was isolated from the garden soil of these women by a hair-baiting technique. The first case had a cat, a mouse and an owl, and the second had a dog. Hairbrush culture of these pets, however, was negative. So we concluded both cases were infected with M. gypseum from garden soil. We isolated M. gypseum from soil collected in Chigasaki city. Of the 7 fungal cultures from 10 samples, 2 cultures were identified as M. gypseum.