Fatal dermatophytic pseudomycetoma in a patient with non-HIV CD4 lymphocytopenia.

Dermatophytic pseudomycetoma is a rare invasive infection, involving both immunocompetent and immunocompromised individuals. Since the discovery of inherited immune disorders such as the impairment of CARD9 gene, extended dermatophyte infections are mostly ascribed to any of these host factors. This study is to present and explore the potential causes in a fatal dermatophytic pseudomycetoma patient. We present a chronic and deep pseudomycetoma caused by the common dermatophyte Microsporum canis which ultimately led to the death of the patient. Mycological examination, genetic studies and host immune responses against fungi were performed to explore the potential factors. The patient had decreased lymphocyte counts with significantly reduced CD4+ T cells, although all currently known genetic parameters proved to be normal. Through functional studies, we demonstrated that peripheral blood mononuclear cells from the patient showed severe impairment of adaptive cytokine production upon fungus-specific stimulation, whereas innate immune responses were partially defective. This is, to our knowledge, the first report of fatal dermatophytic pseudomycetoma in a patient with non-HIV CD4 lymphocytopenia, which highlights the importance of screening for immune deficiencies in patients with deep dermatophytosis.

Tinea capitis in children: A single-institution retrospective review from 2011 to 2019.

Tinea capitis remains a common public health problem worldwide, especially in developing countries. OBJECTIVES: To investigate the changes of the predominant dermatophytes of tinea capitis in children in Hangzhou in recent 9 years. METHODS: The age, gender and pathogen spectrum of 650 children with tinea capitis at the Department of Dermatology, Affiliated Third People's Hospital of Hangzhou, Anhui Medical University from 2011 to 2019 were analysed, and the distribution of pathogens from 1998 to 2000 was compared. RESULTS: Among the 650 cases, 340 cases (48.2%) were males and 310 cases (51.8%) were females. The main population infected with tinea capitis was children aged 0-10 years (620 cases, 95.4%). From 2011 to 2019, the predominant dermatophyte was changed from Trichophyton violaceum (2011) to Trichophyton mentagrophytes complex (2012-2015) and later to Microsporum canis (2016-2019). In the past 9 years, M. canis (250 cases, 38.5%) was the most common dermatophyte and followed by T mentagrophytes complex (209 cases, 32.2%). The dermatophyte spectrum was statistically different between the years 2011 and 2019 (Chi square: χ2  = 69.75, P < .05), and the differences in anthropophilic and zoophilic pathogens between 1989-2000 and 2011-2019 were statistically significant (χ2  = 24.4, P < .05). CONCLUSIONS: Research showed that children diagnosed with tinea capitis were mainly 0-10 years old. With age, the percentage of anthropophilic dermatophytes gradually increased, while the percentage of zoophilic dermatophytes decreased. M. canis was the predominant dermatophyte of tinea capitis in children, followed by T. mentagrophytes complex. The dermatophytes have shifted from anthropophilic to zoophilic dermatophytes in the past two decades.

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.

Prevalence of dermatophytosis in animals and antifungal susceptibility testing of isolated Trichophyton and Microsporum species.

Dermatophytosis is a frequently encountered dermatological problem in domestic and pet animals which negatively affects animal health and production. This study investigated the prevalence of dermatophytosis in different animals and carried antifungal susceptibility testing in the northern Indian state of Uttarakhand. A total of 157 clinical samples were collected from the animals irrespective of sex and age during a time period of 3 years from December 2016 to December 2019. Direct microscopy, fungal culture, isolation, identification, and antifungal susceptibility testing were carried out. Direct microscopy and in vitro culture were equally efficient in diagnosis of dermatophytosis. The prevalence of dermatophytes ranged between 45 and 53.3% and Trichophyton mentagrophytes was the most abundant species (38%) followed by Microsporum canis (21.5%). All the species observed were isolated from goats and dogs except T. tonsurans and M. nanum, respectively. All the isolated dermatophytes were urease test positive except T. rubrum and T. verrucosum. The hair perforation test was negative for M. audouinii, along with T. rubrum and T. verrucosum, whereas only M. canis was positive for rice grain test. Only T. mentagrophytes, T. rubrum, T. verrucosum, and T. tonsurans were able to show optimum growth at 37 °C. Maximum inhibition of fungal growth was exhibited by clotrimazole and least by fluconazole.

Isolation of dermatophytes from dogs and cats in the South of England between 1991 and 2017.

BACKGROUND: Since the epidemiology of canine and feline dermatophytosis might evolve in response to chronological, sociological and ecological factors, the authors studied the occurrence of dermatophyte pathogens over 27 years subsequent to the last major UK survey. METHODS: Dermatophyte culture submission records from dogs and cats to the Royal Veterinary College Diagnostic Laboratory in England between 1991 and 2017 were reviewed. Samples were routinely cultured aerobically at 26°C for up to four weeks on Sabouraud's dextrose agar containing cycloheximide and chloramphenicol; dermatophytes were identified using conventional phenotypic methods. RESULTS: Proportional isolation from cats (15.9 per cent of 1389) exceeded that of dogs (8.1 per cent of 2193) (P<0.001). Together, Microsporum canis and Trichophyton mentagrophytes accounted for 91.9 per cent (n=203) and 80.2 per cent (n=142) of isolations from cats and dogs, respectively. M canis was more frequently (P<0.001) isolated from cats and dogs under two years of age. Dermatophytes were more frequent (P≤0.001) in samples from first-opinion rather than referral practice, and from Jack Russell and Yorkshire terriers and from Persian and chinchilla cats (P≤0.002). CONCLUSIONS: M canis and T mentagrophytes remain the most common agents of canine and feline dermatophytosis in the South of England; continued clinical vigilance is required.

A new molecular marker for species-specific identification of Microsporum canis.

Species identification of dermatophytes by conventional mycological methods based on macro- and microscopy analysis is time-consuming and has a lot of limitations such as slow fungal growth or low specificity. Thus, there is a need for the development of molecular methods that would provide reliable and prompt identification of this group of medically important fungi. The are many reports in the literature concerning PCR identification of dermatophyte species, but still, there are not many PCR assays for the separate detection of members of the genera Microsporum, especially Microsporum canis (zoophilic species) and Microsporum audouinii (anthropophilic species). The correct distinction of these species is important to determine the source of infection to implement the appropriate action to eliminate the path of infection transmission. In this paper, we present such a PCR-based method targeting velB gene that uses a set of two primers-Mc-VelB-F (5'-CTTCCCCACCCGCAACATC-3') and Mc-VelB-R (5'-TGTGGCTGCACCTGAGAGTGG-3'). The amplified fragment is specific due to the presence of (CAGCAC)8 microsatellite sequence only in the velB gene of M. canis. DNA from 153 fungal samples was used in PCR assay followed by electrophoretic analysis. The specificity of the designed set of primers was also confirmed using the online BLAST-Primer tool. The positive results were observed only in the case of M. canis isolates, and no positive results were obtained neither for other dermatophytes and non-dermatophyte fungi nor for other Eukaryotes, including the human genome sequence, as well as the representatives of bacterial and viral taxa. The developed PCR assay using the proposed Mc-VelB-F and Mc-velB-R primers can be included in the algorithm of M. canis detection in animals and humans.

Pseudomycetoma of the scalp caused by Microsporum canis

Abstract Pseudomycetoma is an extremely rare deep mycosis, caused by dermatophytic fungi that penetrate the tissue from infected follicles of tinea capitis. Both clinically and histopathology are similar to eumycetoma, being distinguished through the isolation of the fungus, which in the case of pseudomycetoma can be Microsporum spp. or Trichophyton spp. genre. We present a 24-year-old man with an exuberant tumor in the occipital region with fistula, whose histopathological examination evidenced grains composed of hyaline hyphae and the culture for fungi isolated the agent Microsporum canis. Combined treatment of surgical excision followed by oral griseofulvin for two years was performed, with resolution of the condition.

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.

[Microsporum ferrugineum-an anthropophilic dermatophyte in Germany : Case report and review of the literature]. / Microsporum ferrugineum ­ ein anthropophiler Dermatophyt in Deutschland : Patientenbeschreibung und Übersicht über die Literatur.

Three boys from the same city, treated by the same dermatologist, developed tinea capitis. Two of them, 4 and 8 years old, underwent mycological diagnostic workup. However, no pathogens familiar in this country, such as Microsporum (M.) canis or Trichophyton (T.) tonsurans, were isolated, but instead that of a dermatophyte that has not been found in Germany for decades. Both dermatophyte isolates showed white-beige-brownish colonies with a flat, radiating edge and a central, verrucous curvature. The sequencing of the internal transcribed spacer (ITS) region of the rDNA confirmed the suspicion of M. ferrugineum already expressed based on the morphological picture. The anthropophilic dermatophyte occurs in the Middle East, Asia, Eastern Europe and Africa and is considered to be the cause of tinea capitis or tinea corporis in children and adolescents. In 2016, M. ferrugineum has again been isolated in Germany, probably as a result of migration movements. The fungus is strikingly isolated to martial arts, especially wrestlers. It mainly affects children and adolescents, some with a Russian-German background. The anthropophilic dermatophyte is transmitted directly from person to person, especially in the case of tinea capitis. An indirect transmission, for example, via mats in martial arts is likely.

Epidemiological survey of 42 403 dermatophytosis cases examined at Nagasaki University Hospital from 1966 to 2015.

The causative species of a total of 42 403 dermatophytosis cases that occurred during 1966-2015 were surveyed. The most prevalent clinical type was tinea pedis, followed by tinea unguium, corporis, cruris, manus, faciei and capitis. The prevalence of tinea faciei and capitis has increased since the late 1990s and the late 2000s, respectively. The most prevalent dermatophyte species was Trichophyton rubrum, followed by Trichophyton mentagrophytes (the majority of the isolates were Trichophyton interdigitale in the latest nomenclature). These dermatophytes were detected in over 80% of the isolates identified in tinea pedis, unguium, cruris and manus cases. Recently, Microsporum canis and Trichophyton tonsurans have been increasingly identified. The frequency of M. canis isolated from tinea corporis, faciei and capitis cases started to rise in the early 1990s. T. tonsurans was first identified in Nagasaki in 2003. T. rubrum was the most commonly isolated pathogen in tinea faciei and corporis cases. However, the proportion of cases attributed to it has decreased since the early 1990s, whereas M. canis and T. tonsurans are being increasingly isolated since the early 2000s. In tinea capitis cases, the proportion of each pathogen isolated has changed dramatically. M. canis was first identified in the late 1970s, with an increasing prevalence up to the early 1990s. In contrast, the prevalence of T. tonsurans has increased since the early 2000s. In the 2010s, the most common fungus causing tinea capitis was T. tonsurans, followed by M. canis and T. rubrum.

Pseudomycetoma of the scalp caused by Microsporum canis.

Pseudomycetoma is an extremely rare deep mycosis, caused by dermatophytic fungi that penetrate the tissue from infected follicles of tinea capitis. Both clinically and histopathology are similar to eumycetoma, being distinguished through the isolation of the fungus, which in the case of pseudomycetoma can be Microsporum spp. or Trichophyton spp. genre. We present a 24-year-old man with an exuberant tumor in the occipital region with fistula, whose histopathological examination evidenced grains composed of hyaline hyphae and the culture for fungi isolated the agent Microsporum canis. Combined treatment of surgical excision followed by oral griseofulvin for two years was performed, with resolution of the condition.

Species distribution of the main aetiologic agents causing skin dermatophytosis in Colombian patients: A 23-year experience at a Mycological Reference Center.

BACKGROUND: Dermatophytosis is one of the most frequent superficial mycoses in the world. MAIN AIM: To describe the cases of skin dermatophytosis and its main aetiologic agents in patients referred to a Mycological Reference Laboratory in Medellín, Colombia. METHODS: A retrospective study was carried out with records of patients referred between 1994 and 2016 to the Corporación para Investigaciones Biológicas (CIB), Medellín-Colombia, because of clinical suspicion of skin dermatophytosis. RESULTS: Of a total of 5628 clinical records of patients with suspicion of skin dermatophytosis analysed, 2780 (49.4%) had a proven or probable dermatophytosis diagnosis, 2774 cultures were performed, and aetiologic agents were isolated in 2576 samples (92.9%). The most frequently isolated aetiologic agents were Trichophyton rubrum (44.3%), followed by Trichophyton mentagrophytes complex (33.3%), Epidermophyton floccosum (12.4%), Nannizzia gypseum complex (5.7%, formerly Microsporum gypseum), Microsporum canis (3.5%) and Trichophyton tonsurans (0.8%). The most frequent clinical forms were tinea pedis (72.7%) and tinea corporis (12.7%). In addition, a group of patients (0.9%) developed mixed infections by two dermatophyte agents and another (4.1%) developed infections in more than one anatomical site. CONCLUSIONS: The results of the present study are coherent with previous reports where T rubrum and T mentagrophytes complex were the main causative agents of dermatophytosis. However, the increased incidence of N gypsea complex over M canis is worth highlighting.

One vs two negative fungal cultures to confirm mycological cure in shelter cats treated for Microsporum canis dermatophytosis: a retrospective study.

OBJECTIVES: The aim of this study was to determine how often one negative fungal culture (FC) was indicative of mycological cure (MC) when compared with two negative consecutive FCs in cats treated for Microsporum canis dermatophytosis. METHODS: In this retrospective study, weekly FC data from shelter cats treated for M canis dermatophytosis were reviewed. RESULTS: Complete records from 371 cats were reviewed. The first negative FC was indicative of MC in 335 (90.3%) cats. In this group, all cats were otherwise healthy and either had obvious lesions (n = 237) or no lesions or evidence of resolving lesions (n = 98). In the 36 cats in which the first negative culture was not indicative of MC, there were two clinical subgroups. The first consisted of healthy but lesional cats (n = 19) that had one negative FC within the first 3 weeks of treatment followed by one or more positive FCs. The most likely explanation was sampling error. These cats went on to cure and the next negative FC was indicative of MC. In the second clinical group, cats were lesional but had concurrent medical problems (n = 17). These cats showed an initial good response to treatment (lesion resolution and an initial negative FC). However, this negative FC was followed by at least one strongly positive FC (>10 colony-forming units/plate) before proceeding to cure. These cats took the longest time to cure (mean 11 weeks; range 8-28 weeks). MC occurred after resolution of the concurrent health issues. There was very good agreement between using one negative FC vs two negative FCs for the determination of MC in healthy cats (kappa = 0.903). CONCLUSIONS AND RELEVANCE: In cats where there has been high compliance with environmental cleaning, as well as topical and systemic treatment recommendations, two consecutive negative FCs may not be necessary to determine MC. The first negative FC in an otherwise healthy cat is likely indicative of MC. Good sampling technique is needed to avoid false-negative FC results.

Comparison of carpet and toothbrush techniques for the detection of Microsporum canis in cats.

OBJECTIVES: The aim of this study was to evaluate the diagnostic concordance between the toothbrush and carpet techniques for the detection of Microsporum canis in cats in a field study. METHODS: Thirty-nine Persian cats from a cattery were used. Fungal culture samples from the haircoat of each cat were collected by stroking the coat with a sterile toothbrush and a 5 × 5 cm-sized sterile carpet square (n = 78 total samples). Specimens were inoculated onto Mycosel Agar and incubated at 25°C for 21 days. Both techniques were compared using the following parameters: number of plates without fungal growth, number of plates with contaminant growth and number of plates positive for dermatophytes. RESULTS: The feline population in the study cattery was 39. Thirty (77%) were symptomatic and nine (23%) asymptomatic. The diagnosis was made via carpet and toothbrush methods and 78 cultures were performed. On day 21, M canis was detected in all culture plates. No contaminant molds were observed. CONCLUSIONS AND RELEVANCE: The concordance rate between the carpet and toothbrush techniques among the 78 evaluable culture plates was 100%. Both methods are equally effective for collecting material for Mcanis culture. Additionally, both techniques are inexpensive and easy to perform in feline clinical practice.

Retrospective two-centre study on prepubertal children with Tinea capitis in Korea.

Tinea capitis is an infectious dermatological disorder caused by dermatophytes that occur primarily in children. It has recently been brought under effective control in Korea since the introduction of oral antifungal medications and the implementation of concerted public health initiatives. Therefore, its incidence rate has decreased considerably. We investigated changes in the epidemiological and mycological characteristics of tinea capitis patients under the age of 10 in Korea. Using medical records from Kyungpook National University Hospital and the Catholic Skin Disease Clinic from 1989 to 2018, we retrospectively investigated the characteristics of 786 patients with tinea capitis. Of the 786 patients, 744 were KOH-positive. The annual incidence of tinea capitis was decreased from 120 to less than 10 between 1989 and 2018. Overall, 446 (56.74%) were male and 340 (43.26%) were female, representing a ratio of 1:0.8. In terms of the seasonality of it, 276 (35.11%) visited hospital in winter, 193 (24.55%) in spring, 177 (22.52%) in fall and 140 (17.81%) in summer. Dermatophytes were cultured from 628 patients. Microsporum canis was the most common dermatophyte (73.16%), followed by Trichophyton verrucosum and Trichophyton rubum. Of the 786 patients, 577 (73.41%) lived in urban areas and 209 (26.59%) in rural areas. Changes in the epidemiological and mycological characteristics of children with tinea capitis were shown in incidence, sex distribution, seasonality and causative dermatophytes. The incidence of tinea capitis has fallen significantly in prepubertal children. Nevertheless, continuous surveillance is needed to prevent tinea capitis in Korea.

Microsporum audouinii: un dermatofito causante de una tiña reemergente / Microsporum audouinii: Re-Emergence of Ringworm Due to the Dermatophyte

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