Exploring treatment and antifungal resistance in an outbreak of tinea caused by Microsporum audouinii.

BACKGROUND: Microsporum audouinii has resurged recently. Infections with the dermatophyte are difficult to treat, which raises the question if we treat M. audouinii infections with the most effective antifungal (AF) agent. OBJECTIVES: The aims of this study was to investigate an outbreak of tinea capitis (TC) in Denmark, address the challenges in outbreak management and to conduct two reviews regarding previous outbreaks and minimal inhibitory concentration (MIC). METHODS: We used Wood's light, culture, direct microscopy, and PCR for screening and antifungal susceptibility testing (AFST) for treatment optimization. We performed two reviews to explore M. audouinii outbreaks and MIC values using broth microdilution method. RESULTS: Of 73 screened individuals, 10 had confirmed M. audouinii infections. Clinical resistance to griseofulvin was observed in 4 (66%) cases. While previous outbreaks showed high griseofulvin efficacy, our study favoured terbinafine, fluconazole and itraconazole in our hard-to-treat cases. AFST guided the choice of AF. Through the literature search, we identified five M. audouinii outbreaks, where differences in management included the use of Wood's light and prophylactic topical AF therapy. Terbinafine MIC values from the literature ranged from 0.002 to 0.125 mg/L. CONCLUSION: Use of Wood's light and preventive measurements were important for limiting infection. The literature lacked MIC data for griseofulvin against M. audouinii, but indicated sensitivity for terbinafine. The clinical efficacy for M. audouinii treatment was contradictory favouring both terbinafine and griseofulvin. AFST could have a key role in the treatment of difficult cases, but lack of standardisation of AFST and MIC breakpoints limits its usefulness.

An international survey of recalcitrant and recurrent tinea of the glabrous skin-A potential indicator of antifungal resistance.

BACKGROUND: There has been a global rise in cases of dermatophytosis and, in particular, recalcitrant and recurrent cases on tinea of the glabrous skin. This phenomenon, particularly prevalent in India, has been linked to the concerning rise of antifungal resistance. The challenge is amplified by a dearth of comprehensive, international data to understand the global scope and characteristics of such cases. OBJECTIVES: This study aims to collate international insights, focusing on areas outside Europe (as this was previously published), to map the extent and characteristics of clinical and, where possible, laboratory confirmed tinea of the glabrous skin through an online survey administered to dermatologists globally. METHODS: An online survey was distributed from February 2022 to July 2023 and captured data on respondents' experience of recalcitrant and recurrent tinea of the glabrous skin over the preceding 3 years. RESULTS: A total of 260 responses were received spreads across 36 countries, excluding Europe. In total, 91.7% reported seeing cases of recalcitrant or recurrent tinea of the glabrous skin over the preceding 3 years. Common anatomical sites affected were the trunk and groin. T. mentagrophytes and T. rubrum were the predominant species implicated, and there were low rates of laboratory confirmed dermatophyte resistance. CONCLUSIONS: The high rates of reported recalcitrant and recurrent tinea of the glabrous skin underscore an urgent need for global collaborative efforts and enhanced diagnostic measures. The findings advocate for the establishment of a standardized global disease registry, regulation of over-the-counter antifungal and steroid combinations, correlation of clinical suspicion with laboratory confirmed drug resistance and exploration of alternative therapeutic strategies to mitigate the burgeoning challenge of dermatophyte resistance.

Tumor necrosis factor-α inhibitor treatment of acne fulminans - a clinical and literature review.

Acne fulminans (AF) is a rare, serious, sudden-onset and long-lasting skin disease that causes scarring of face and body. Standard treatment with combined long-term isotretinoin and prednisolone is not always sufficient and has a well-known propensity for adverse effects leaving an unmet need for improved therapy. Case reports suggest that tumor necrosis factor (TNF)-α inhibitors may play a role in the management of AF. In a 3-year retrospective data collection from two dermatology centers and literature review of clinical cases of acne fulminans treated with anti-TNF-α therapy, three clinical cases and twelve literature cases were identified. A total of five different TNF-α inhibitors have been tested, with adalimumab being the most commonly used. Clinical response was seen after 1 month in 2/3 (67%) clinical cases and 5/12 (42%) literature cases, respectively, and treatment was successful in 2/3 (67%) and 11/12 (92%) after a median 3-7 months. All reported adverse effects were mild and reversible. Anti-TNF-α treatment may provide rapid improvement in patients with AF when initial treatment with isotretinoin and prednisolone fails. However, randomized controlled trials are lacking, and exact dosage and timing need to be explored before clinical implementation.

The Emerging Terbinafine-Resistant Trichophyton Epidemic: What Is the Role of Antifungal Susceptibility Testing?

BACKGROUND: Dermatophytosis is commonly encountered in the dermatological clinics. The main aetiological agents in dermatophytosis of skin and nails in humans are Trichophyton (T.) rubrum, T. mentagrophytes and T. interdigitale (former T. mentagrophytes-complex). Terbinafine therapy is usually effective in eradicating infections due to these species by inhibiting their squalene epoxidase (SQLE) enzyme, but increasing numbers of clinically resistant cases and mutations in the SQLE gene have been documented recently. Resistance to antimycotics is phenotypically determined by antifungal susceptibility testing (AFST). However, AFST is not routinely performed for dermatophytes and no breakpoints classifying isolates as susceptible or resistant are available, making it difficult to interpret the clinical impact of a minimal inhibitory concentration (MIC). SUMMARY: PubMed was systematically searched for terbinafine susceptibility testing of dermatophytes on October 20, 2020, by two individual researchers. The inclusion criteria were in vitro terbinafine susceptibility testing of Trichophyton (T.) rubrum, T. mentagrophytes and T. interdigitale with the broth microdilution technique. The exclusion criteria were non-English written papers. Outcomes were reported as MIC range, geometric mean, modal MIC and MIC50 and MIC90 in which 50 or 90% of isolates were inhibited, respectively. The reported MICs ranged from <0.001 to >64 mg/L. The huge variation in MIC is partly explained by the heterogeneity of the Trichophyton isolates, where some originated from routine specimens (wild types) whereas others came from non-responding patients with a known SQLE gene mutation. Another reason for the great variation in MIC is the use of different AFST methods where MIC values are not directly comparable. High MICs were reported particularly in isolates with SQLE gene mutation. The following SQLE alterations were reported: F397L, L393F, L393S, H440Y, F393I, F393V, F415I, F415S, F415V, S443P, A448T, L335F/A448T, S395P/A448T, L393S/A448T, Q408L/A448T, F397L/A448T, I121M/V237I and H440Y/F484Y in terbinafine-resistant isolates.

Disinfection trials with terbinafine-susceptible and terbinafine-resistant dermatophytes.

BACKGROUND: Treatment of tinea pedis and onychomycosis is complicated by high rates of reinfection and the emergence of terbinafine-resistant strains of Trichophyton spp. Effective disinfection of contaminated socks is an important measure. Appropriate washing reduces the risk of reinfection and is paramount in treating tinea pedis and onychomycosis. OBJECTIVES: The aim of this study was to describe the effect of commonplace disinfection methods using socks pieces inoculated with terbinafine-resistant or terbinafine-susceptible isolates of Trichophyton spp. METHODS: Sock pieces were inoculated with seven terbinafine-resistant isolates of Trichophyton spp. with known mutations in the SQLE-gene (T. rubrum (n = 3), T. interdigitale (n = 1) and T. indotineae (n = 3)) and six terbinafine-susceptible isolates of Trichophyton spp. (T. rubrum (n = 3) and T. interdigitale (n = 3)). Methods of disinfection included soaking in a quaternary ammonium (QAC) detergent (0.5, 2 and 24 h), freezing at -20°C (0.5, 12 and 24 h), domestic and steam washing (both at 40°C with detergent). Sock pieces were cultured for 4 weeks following disinfection. The primary end point was no growth at the end of week 4. RESULTS: Soaking in a QAC-detergent for 24 h procured at disinfectant rate of 100% (13/13), whilst soaking in 0.5 and 2 h had a disinfectant rate of 46.2% (6/13) and 84.6% (11/13), respectively. Domestic washing (40°C with detergent) produced a disinfectant rate of 7.7% (1/13). Freezing at -20°C (0.5, 12 and 24 h) and steam washing (40°C with detergent) had no disinfectant properties. CONCLUSIONS: Soaking in a QAC-detergent for 24 h effectively disinfected sock pieces contaminated with dermatophytes.

Systematic review of the prevalence of onychomycosis in children.

Onychomycosis is one of the most common nail diseases in adults but is described as infrequent in children. Data are, however, scattered and diverse. Studies have nevertheless suggested that the prevalence of onychomycosis is increasing in children lately and the aim of this review was therefore to examine this problem. Two authors individually searched PubMed, Embase, and Cochrane Library for articles on epidemiology and prevalence of onychomycosis in children. The literature search was conducted in accordance per PRISMA guidelines. In total 1042 articles were identified of which 23 were eligible for inclusion. One of the articles presented two studies and a total of 24 studies were therefore included. Seventeen studies presented data of the prevalence of onychomycosis in children in the general population and seven studies among children visiting a dermatological and pediatric department or clinic. The prevalence ranged from 0% to 7.66% with an overall discrete increase of 0.66% during the period 1972 to 2014 in population studies (not statistically significant). This review supports a trend towards an increased prevalence of onychomycosis in children, albeit based on a paucity of studies. The data suggests an increasing prevalence of onychomycosis with age, and co-infection with tinea pedis (reported in 25% of the studies). The most common pathogen reported was Trichophyton rubrum and onychomycosis was more prevalent in toenails compared to fingernails. The general characteristics of onychomycosis in children are thus similar to those described in adults.

Identification of cutaneous fungi and mites in adult atopic dermatitis: analysis by targeted 18S rRNA amplicon sequencing.

BACKGROUND: Atopic dermatitis (AD) patients have an altered skin bacterial community, with an abundance of Staphylococcus aureus associated with flares, highlighting that microbial organisms may be important for disease exacerbation. Despite strong evidence of association between bacterial skin colonisation and AD, very limited knowledge regarding the eukaryotic microbial community, including fungi and ectoparasites, in AD exists. In this study, we compared the skin and nasal eukaryotic microbial community between adult AD patients (n = 55) and non-AD healthy controls (n = 45) using targeted 18S rRNA amplicon sequencing. Analysis was based on the presence or absence of eukaryotic microorganisms. RESULTS: The cutaneous composition of the eukaryotic microbial community and the alpha-diversity differed significantly between AD patients and non-AD individuals, with increased species richness on AD skin. Alpha-diversity and beta-diversity were similar on lesional and non-lesional skin of patients. The ectoparasite Demodex folliculorum and the yeast Geotrichum candidum were significantly more prevalent on the skin of AD patients. The prevalence of D. folliculorum on lesional skin was greater among patients recently treated with topical corticosteroid. Malassezia was one of the most frequently detected genera at all sites, with M. globosa and M. restricta being the most prevalent. M. restricta was under represented in the anterior nares of AD patients as compared to the non-AD control population. CONCLUSION: Significant differences in the eukaryotic microbial communities were found between AD patients and non-AD individuals, with the most striking finding being the significantly overrepresentation of D. folliculorum on AD skin. Whether D. folliculorum can contribute to skin inflammation in AD needs further investigation.

Treatment adherence and psychosocial impact of tinea capitis in families: Qualitative pilot study.

Tinea capitis (TC) is a fungal infection of the hair and scalp. It mainly affects children, and treatment requires an extensive regimen including oral therapy, antifungal creams, and shampoo, as well as disinfection of fomites, bed linen, and clothes. Family members to patients with TC need prophylactic treatment to limit spread of the infection. Adherence to therapy in TC is time consuming, and the disease may cause psychosocial impairment to the caregivers. In this study, we performed interviews with parents to children with TC to identify factors related to treatment adherence and psychosocial implications from the parent's perspective. The interviews were performed and recorded at a dermatology outpatient clinic in Roskilde, Denmark (2018-2019). A total of 11 families agreed to participate in the study. The families had one to four affected children (age range: 1-14 years). We found that the key factors affecting adherence were the level of cooperation between the child and their parent, lack of symptoms in family members, and language barrier. The psychosocial well-being of parents was negatively affected due to fear of stigma and the time spent on treatment. Our study emphasizes the need for proper treatment instructions and psychosocial support of the parents by healthcare professionals.

Systematic Review of Complications and Recurrences After Surgical Interventions in Hidradenitis Suppurativa.

BACKGROUND: The possible connection between hidradenitis suppurativa (HS) patients undergoing surgery and higher complications/recurrences has been implied, but inconsistent results reported. OBJECTIVE: To assess the complication and recurrence rates for HS patients undergoing surgery and to evaluate whether known HS comorbidities and habits (smoking, obesity and diabetes) have an effect on the complication and recurrence rates. MATERIALS AND METHODS: A systematic review was conducted by 2 reviewers. PubMed and Embase were searched using a predefined search string created in collaboration between the authors and a librarian on January 23, 2019. RESULTS: Of the 271 references in the original search, 54 relevant articles were identified. This systematic review indicates an overall mean complication rate of 24% and a mean recurrence rate of 20.1% for HS patients undergoing surgery. CONCLUSION: No significant association between the known surgical risk factors and surgical complications-or recurrence rates in this patient group was found. This review revealed a lack of quality and quantity data in studying the complications/recurrences. The heterogeneity of the studies created limitations, and the presented mean complication/recurrence rates should be interpreted with the consequences thereof. It elucidates the need for better studies and a necessity for a standardized definition of postsurgical HS recurrence.

Would you like to purchase a rodent with dermatophytes?

The zoophilic dermatophyte Trichophyton benhamiae has received attention due to increasing infections in human in recent years. Trichophyton benhamiae has been found on asymptomatic rodents from pet shops in several countries posing a potential risk for transmission to humans. The aim of this study was to determine the prevalence of positive dermatophyte cultures from rodents in Danish pet shops in order to clarify the magnitude of potential sources of zoophilic infections and to prevent further spread. Specimen sampling was performed in 17 Danish pet shops using the brush technique (MacKenzie technique). After incubation, cultures were sent to ITS DNA sequencing for molecular species identification. Pet shop employees were asked to fulfil a five-question survey regarding purchase and procedures of diseased animals. A total of 98 animals were sampled (N = 32 rabbits, N = 32 guinea pigs and N = 34 hamsters). Trichophyton benhamiae was found in 14/98 samples (14%); 12/32 guinea pigs (38%) were positive with T benhamiae, 2/34 (6%) hamsters and 0/32 rabbits (0%). We found that hamsters and particularly guinea pigs from Danish pet shops are common asymptomatic carriers of the dermatophyte T benhamiae. Although a larger study is warranted to test this postulate, and it raises the question if infection control measures should be implemented in pet shops.

Hidradenitis Suppurativa: Advances in Diagnosis and Treatment.

IMPORTANCE: Hidradenitis suppurativa (HS) is relatively common, with the prevalence of 0.05% to 4.10%, yet many patients receive inadequate treatment. OBJECTIVE: To review the diagnosis, epidemiology, and treatment of HS with an emphasis on advances in the last 5 years. EVIDENCE REVIEW: A literature search was conducted using PubMed, MEDLINE (Medical Subject Headings [MeSH]), and EMBASE to include recently published treatment studies (searched from September 1, 2011, to May 1, 2017). Reviews, guidelines, conference abstracts, and studies with less than 10 patients were excluded. Furthermore, internet searches for guidelines on hidradenitis suppurativa using Baidu, Bing, Google, and Qwant browsers were performed. FINDINGS: The diagnosis of HS is made by lesion morphology (nodules, abscesses, tunnels, and scars), location (axillae, inframammary folds, groin, perigenital, or perineal), and lesion progression (2 recurrences within 6 months or chronic or persistent lesions for ≥3 months). HS is more common than was previously thought based on epidemiological analysis (0.05%-4.10%). Disability from HS can be significant. Patients with HS may have significant comorbidities (eg, obesity, metabolic syndrome, diabetes, and arthritis) and increased all-cause mortality (incidence rate ratio, 1.35 [95% CI, 1.15-1.59]). Antibiotic treatment with combinations of clindamycin and rifampicin, or ertapenem followed by combination rifampicin, moxifloxacin, and metronidazole for 6 months is effective. Adalimumab is effective in a significant proportion of patients and treatment with IL-1 and IL-12 receptor subunit beta 1 (Rb1) antibodies may also be useful. Tissue-sparing surgical techniques and carbon dioxide laser treatments also are available, but the evidence on clinical outcomes with these approaches is limited. CONCLUSIONS AND RELEVANCE: Hidradenitis suppurativa is more common than previously thought and may be treated by an array of pharmacological and surgical techniques. Hidradenitis suppurativa should be considered in the differential diagnosis of nodular lesions or sinus tracts present in the axillae, groin, perineal, and mammillary fold regions.

The bacteriology of hidradenitis suppurativa: a systematic review.

Hidradenitis suppurativa (HS) is a chronic inflammatory disabling skin disease consisting of recurrent nodules, sinuses, fistulas and scarring involving the intertriginous regions. HS is often a therapeutic challenge and most treatments are off-label. A better understanding of aetiology and pathogenesis of HS may facilitate the development of effective treatment. Although the clinical presentation is strongly reminiscent of bacterial infection, the role of bacteria remains controversial. Studies have isolated an array of different bacteria specimens. Consistent findings of Gram-positive cocci and Gram-positive rods including Staphylococus aureus, coagulase-negative staphylococci (CoNS) and Corynebacterium species in deep tissue samples have been demonstrated in HS and may constitute a central target for the immune system. Efficacy of antibiotics, that is rifampicin, clindamycin or tetracycline, supports a microbial role in disease pathogenesis. However, these antibiotics also work as immunomodulators of especially T cells, and the underlying mechanisms may therefore be more complex. We performed a systematic review of previous studies investigating the bacterial flora in hidradenitis suppurativa. We searched PubMed, EMBASE, Royal Danish Library and Cochrane library (search date 11 December 2014). A total of 66 papers were identified and nine papers published between 1988 and 2014 matched our inclusion criteria, yielding bacteriological data of a total of 324 patients with HS (mean age 36.8 years and female/male ratio 215/109). This overview of the bacteriology may aid researchers and physicians exploring the potential role of bacteria in HS. Furthermore, to stimulate a broader debate, we also present different viewpoints on the possible role of bacteria in HS.

Evidence-based Danish guidelines for the treatment of Malassezia-related skin diseases.

Internationally approved guidelines for the diagnosis and management of Malassezia-related skin diseases are lacking. Therefore, a panel of experts consisting of dermatologists and a microbiologist under the auspices of the Danish Society of Dermatology undertook a data review and compiled guidelines for the diagnostic procedures and management of pityriasis versicolor, seborrhoeic dermatitis and Malassezia folliculitis. Main recommendations in most cases of pityriasis versicolor and seborrhoeic dermatitis include topical treatment which has been shown to be sufficient. As first choice, treatment should be based on topical antifungal medication. A short course of topical corticosteroid or topical calcineurin inhibitors has an anti-inflammatory effect in seborrhoeic dermatitis. Systemic antifungal therapy may be indicated for widespread lesions or lesions refractory to topical treatment. Maintenance therapy is often necessary to prevent relapses. In the treatment of Malassezia folliculitis systemic antifungal treatment is probably more effective than topical treatment but a combination may be favourable.

PCR test for Microsporum canis identification.

Microsporum canis, for which the natural hosts are cats and dogs, is the most prevalent zoophilic agent causing tinea capitis and tinea corporis in humans. We present here a diagnostic PCR test for M. canis, since its detection and species identification is relevant to the choice of treatment and to the understanding of a probable source of infection. An M. canis-specific PCR was evaluated using 130 clinical isolates of dermatophytes (including M. canis [n = 15] and 13 other species), 10 yeast or mold isolates, 12 hair and skin samples from animals with or without experimental M. canis infection, and 35 patient specimens, including seven specimens positive for M. canis and 15 dermatophyte negative samples. All pure cultures, animal specimens and clinical samples with M. canis were detected by the PCR test, whereas none of the other fungal isolates or samples without M. canis was negative. This study indicates that the PCR test for M. canis identification applied directly to patient specimens or animal hair, as well as to clinical isolates had 100% specificity and sensitivity.

Laser and intense pulsed light in the treatment of hidradenitis suppurativa.

Treatment of hidradenitis suppurativa (HS) requires a combination of medical, surgical, and lifestyle interventions. Intense pulsed light (IPL) and lasers have been reported to be useful. The aim of this review is to find the evidence supporting IPL and laser treatment of HS and to provide guidance for the management of specific HS lesions. We searched PubMed and Web of Science for "laser" and "hidradenitis suppurativa" on April 6, 2022. Inclusion criteria were >10 patients, reported follow-up, English language, and human subjects with a diagnosis of HS. A total of 724 articles were screened, but only 17 studies qualified for inclusion (IPL (n = 4), Nd:YAG (n = 6), CO2 laser (n = 6), and intralesional treatment (n = 2). The majority of the studies had a low (n = 10) or moderate (n = 7) evidence level. Treatment effect was noticed in studies using IPL and Nd:YAG (hair reduction). CO2 laser was used for surgery with a success rate ranging from 70.7% to 96.7%. CO2 laser is useful for surgery of stationary HS lesions, but it is difficult to draw a conclusion on the use of IPL and Nd:YAG (hair reduction) as the studies were too heterogeneous to perform a meta-analysis.

Primary skin abscess microbiota a systematic review.

An abscess is a collection of pus forming a cavity in the tissue, for example, the skin. They are generally perceived as the result of infection but infection is not mandatory for the diagnosis. Skin abscesses may occur independently (primary) or be part of other diseases such as the recurrent inflammatory skin disease hidradenitis suppurativa (HS). HS is noninfectious but nevertheless abscesses are a common differential diagnosis. The purpose of this study is to review the microbiome of bacteria positive primary skin abscesses in order to explore the reported microbiota. EMBASE, MEDLINER, and COCHRANE LIBRABRY were searched on 9th of October 2021 for microbiome, skin, and abscesses. Studies with more than 10 patients reporting the microbiome in human skin-abscesses were included and studies with abscess microbiota sampled from HS patients, microbiota not sampled from skin-abscesses, missing information on microbiome data, sampling bias, studies in other language than English or Danish, reviews and meta-analyses were excluded. In total 11 studies were included for further analysis. S. aureus is likely to dominate the microbiome of bacteria positive primary skin abscesses in contrast to the polymicrobial microbiome of HS.

A survey of students' and junior doctors' confidence in diagnosing in skin of colour.

INTRODUCTION: To combat ethnic inequalities in health, medical students should be prepared to treat all patients. Denmark has become an increasingly diverse society and therefore needs a medical curriculum that reflects the change in population composition. This study aimed to assess if the dermatology curriculum in Denmark prepared medical students to diagnose dermatological diseases in patients with skin of colour (SoC). METHODS: From 20 September to 12 October 2022, a survey was distributed to medical students and junior doctors who had completed the dermatology curriculum at one of the medical schools in Denmark between 2010-2022. The participants were recruited mainly via Facebook. The statistical data were analysed in STATA, and free-text responses were analysed using thematic analysis. RESULTS: A total of 592 medical students (n = 285) and junior doctors (n = 307) completed the survey. In SoC, 43.9% and 32.6% felt confident to a poor or very poor degree in diagnosing dermatological diseases versus 5.9% and 2.5% in white skin. Among others, the respondents suggested to increase visual examples in the curriculum and integrate SoC in exams to increase their confidence level when diagnosing in SoC. CONCLUSION: Danish medical students and junior doctors are significantly less confident when diagnosing dermatological diseases in SoC than in white skin. Revision of the dermatology curriculum is needed to increase the students' confidence level and knowledge of SoC to prepare them to treat all patients, ultimately reducing ethnic inequalities in health. FUNDING: None. TRIAL REGISTRATION: Not relevant.