Molecular Detection of Dermatophytes and Nondermatophytes in Onychomycosis in Antalya, Turkey.

BACKGROUND: Onychomycosis is a chronic nail infection, and dermatophytes, yeasts, and nondermatophytic molds may be the causative agents. This study aimed to determine the etiological agents of onychomycosis by using conventional and molecular methods. METHODS: Between June 2020 and July 2021, 37 patients with a presumptive diagnosis of onychomycosis and mycological evidence (culture and/or EUROArray Dermatomycosis assay) were included in the study. Organisms detected in cultured nail specimens were identified by combined phenotypic characteristics and by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). An EUROarray Dermatomycosis assay was used for molecular detection of fungal pathogens. RESULTS: The EUROArray Dermatomycosis assay was positive for a single fungal target in 23 samples, and 14 samples were positive by culture. The most common pathogen was Trichophyton rubrum in both methods. Coinfection was detected in 14 samples by using molecular methods, and Trichophyton rubrum and Fusarium solani (9 samples) were the most common pathogens detected together. Trichophyton spp., nondermatophyte molds, and Candida spp. were detected in 33 (89.2%), 16 (43.2%), and 6 (16.2%) samples, respectively, when the two methods were evaluated together. CONCLUSIONS: Our results revealed that fungal culture allows the diagnosis of onychomycosis, but it is not as sensitive as the EUROArray Dermatomycosis test, especially in patients receiving antifungal therapy.

Epidemiology of Tinea Capitis Among School-Children in Dschang, Western Cameroon.

Data on the epidemiology of tinea capitis (TC), an infection of the scalp by dermatophytes, are scarce in Cameroon. This study aimed to determine the prevalence of TC among school-children in the Dschang Subdivision, Western Cameroon. A cross-sectional study was carried out in June 2021 in Dschang including pupils aged 5-13. First, a standardized questionnaire was administered to participant for the collection of sociodemographic data. Then, samples were collected and cultured onto Sabouraud-Chloramphenicol-Gentamicin Agar. The etiological agents were identified based on their morphological features and with MALDI-TOF mass spectrometry. A total of 1070 children were clinically examined and 108 (10.1%) children presented with TC lesions. The mean age of the 1070 participants was 8.3 ± 2.6 years (range: 5-13 years); 772 (72.2%) were males. The use of borehole water (OR = 0.01, 95%CI[0.001-0.03]), spring water (OR = 0.2, 95%CI[0.08-0.50]), rainwater (OR = 0.004, 95%CI[0.001-0.016]), and hairdressing salons visits (OR = 0.413, 95%CI[0.196-0.872]) were associated with a decreased TC risk in the multivariate logistic regression analysis. In contrast, sharing bed with siblings (OR = 4.48, 95%CI[2.095-9.60]) was associated with an increased TC risk in children. Among the 32 dermatophytes isolated in culture, Microsporum audouinii was the most frequent (43.8%), followed by Trichophyton rubrum (25.0%) and T. soudanense (25.0%). Microsporum canis and T. violaceum were both rarely isolated. Further studies are warranted to assess the association of TC with domestic water usage that has been highlighted in this study.

Internal Transcribed Spacer Region Typing of Trichophyton interdigitale Isolated from Japanese Patients.

Trichophyton interdigitale, an anthropophilic species, is one of the main causative agents of tinea unguium and tinea pedis. T. interdigitale and the zoophilic species T. mentagrophytes are morphologically and physiologically very similar. Isolates of the T. interdigitale/T. mentagrophytes complex from around the world have been classified into more than 10 internal transcribed spacer (ITS) genotypes. In this study, we isolated T. interdigitale from Japanese patients and investigated which ITS type was more common. The ITS regions of 29 clinical isolates of T. interdigitale and one clinical isolate of T. mentagrophytes were sequenced. The phylogenetic analysis of the ITS region sequences revealed that the 29 isolates of T. interdigitale belong to ITS type II of T. interdigitale. The one clinical isolate of T. mentagrophytes was in the same cluster with ITS type II* of T. mentagrophytes. One terbinafine-resistant strain of T. interdigitale also belonged to ITS type II of T. interdigitale.

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.

Evaluation of DermaGenius® resistance real-time polymerase chain reaction for rapid detection of terbinafine-resistant Trichophyton species.

BACKGROUND: Treatment-resistant dermatophytosis caused by Trichophyton mentagrophytes/interdigitale complex has emerged as a global public health threat, particularly in endemic countries like India and has spread to many other countries. This veritable spread is alarming due to increase in resistance to terbinafine, which targets the ergosterol biosynthetic pathway by inhibiting the enzyme squalene epoxidase (SQLE). About two third of studies worldwide have reported amino acid substitutions Phe397Leu and Leu393Phe in the SQLE protein to be responsible for high terbinafine MICs. OBJECTIVES: We evaluated the efficacy of the newly developed DermaGenius® Resistance real-time PCR assay to rapidly identify Trichophyton isolates harbouring most common SQLE mutant (Phe397Leu and Leu393Phe) conferring high terbinafine resistance from wild-type susceptible isolates. METHODS: A total of 97 Trichophyton isolates confirmed by ITS sequencing as T. mentagrophytes/interdigitale (recently named T. indotineae n = 90), T. rubrum/T. soudanense (n = 3), T mentagrophytes (n = 2) and T tonsurans (n = 2) were analysed to evaluate DermaGenius® Resistance real-time PCR assay. All 40 T. indotineae isolates exhibiting amino acid substitutions Phe397Leu or Leu393Phe identified by SQLE gene sequencing were evaluated for detection of non-wild-type strains by real-time PCR. Antifungal susceptibility testing for terbinafine was done by CLSI microbroth dilution method. RESULTS: All terbinafine-resistant isolates harbouring amino acid substitutions Phe397Leu or Leu393Phe in SQLE gene were correctly recorded as SQLE mutants by the DermaGenius® Resistance real-time PCR assay. CONCLUSIONS: The DermaGenius® Resistance real-time PCR assay effectively identified Trichophyton species and distinguished wild-type from SQLE mutant genotype that harbour Phe397Leu and Leu393Phe amino acid substitutions.

Complementary effect of mechanism of multidrug resistance in Trichophyton mentagrophytes isolated from human dermatophytoses of animal origin.

BACKGROUND: Dermatophytoses have gained interest worldwide due to the increased resistance to terbinafine and azoles and difficulty in management of these refractory diseases. OBJECTIVES: In this study, we identified and analysed Trichophyton mentagrophytes clinical isolates obtained from humans with infections of animal origin. METHODS: We used quantitative real-time PCR (qRT-PCR) to examine the transcriptional modulation of three MDR genes (PDR1, MDR2 and MDR4) and analysed squalene epoxidase (SQLE) gene sequences from multidrug-resistant Trichophyton mentagrophytes isolates. RESULTS: The expression profile revealed a 2- to 12-fold increase in mRNA accumulation in the presence of any of the antifungals, compared to cells incubated without drugs. A statistically significant relationship between the isolates exposed to itraconazole and increased expression of the tested genes was revealed. Substantially lower transcription levels were noted for cells exposed to luliconazole, that is, a third-generation azole. Additionally, in the case of 50% of terbinafine-resistant strains, Leu397Phe substitution in the SQLE gene was detected. Furthermore, the reduced susceptibility to itraconazole and voriconazole was overcome by milbemycin oxime. CONCLUSIONS: In conclusion, our study shed more light on the role of the ABC transporter family in T. mentagrophytes, which, if overexpressed, can confer resistance to single azole drugs and even cross-resistance. Finally, milbemycin oxime could be an interesting compound supporting treatment with azole drugs in the case of refractory dermatomycoses.

A case of Tinea Faciei caused by Trichophyton benhamiae: first report in China.

BACKGROUND: Trichophyton benhamiae is a zoophilic dermatophyte that can cause tinea in humans and animals. Lesions caused by T. benhamiae tend to be highly inflammatory, and patients are often infected by animals or other patients infected with T. benhamiae. In this paper, we report the first case of tinea faciei caused by T. benhamiae in a Chinese girl who might be transmitted from a fox. CASE PRESENTATION: A 4-year-old girl from HaiNing city developed an itchy, erythematous, and annular plaque on her right face for the past 2 months. Before the lesion appeared, she was in close contact with the fur of a fox for almost 1 week. Septate hyaline hyphae were detected by direct mycological examination of the scales. Cultures grew on Sabouraud's dextrose agar (SDA) at 26 °C for 2 weeks revealed the presence of T. mentagrophytes. A molecular sequencing test confirmed that the isolate was consistent with reference strains to T. benhamiae. Then, the diagnosis of tinea faciei due to T. benhamiae was made. Treatment with terbinafine (oral 125 mg/d) and sertaconazole nitrate cream (topical, twice daily) for 4 weeks was initiated and achieved significant improvement of the skin lesions. CONCLUSIONS: This rare dermatophytosis case highlights the importance of ITS sequencing in helping to recognize rare pathogenic fungi that can be easily misdiagnosed with a conventional morphological diagnosis.

Clinical isolates of Trichophyton rubrum are completely inhibited by photochemical treatment with a γ-cyclodextrin formulation of curcuminoids.

INTRODUCTION: It was shown previously that dermatophytes can markedly be inhibited by a photochemical treatment with curcumin. This kind of photo-inactivation needs to be improved, however, because curcumin is poorly water-soluble. Therefore, a new water-soluble γ-cyclodextrin formulation of curcuminoids was tested for its photochemical inactivation of Trichophyton (T.) rubrum. MATERIALS AND METHODS: Conidia were harvested from 6 typical strains of T rubrum and used to inoculate wells of microtiter plates. These wells were also filled with a γ-cyclodextrin curcuminoid formulation with 0.1% DMSO and Sabouraud broth. The assays were then irradiated with visible light (wavelength 420 nm, 45 J/cm2 ). After 24 hours, curcuminoid was added once more, and irradiation was repeated. Fungal growth was monitored photometrically for 8 days and compared with controls. RESULTS: Growth of all 6 T rubrum strains was completely inhibited by the photochemical treatment with the γ-cyclodextrin formulation of curcuminoids. The same curcuminoid formulation applied without irradiation had only a minor inhibitory effect. DISCUSSION: Photo-inactivation of dermatophytes with a γ-cyclodextrin formulation of curcuminoids plus visible light is a very promising procedure with potential for a new treatment of patients with superficial tinea.

Clinico-mycological study of onychomycosis in a tertiary care hospital-A cross-sectional study.

Onychomycosis (OM), has a worldwide prevalence of 5% and 0.5%-5% in India. Trichophyton. rubrum (T rubrum) and T mentagrophytes are the most commonly isolated fungi. As the clinical and mycological characteristics change with time and geographical region; it is important to study the temporal and topographic patterns periodically. The study was conducted to identify the epidemiological and clinico-mycological characteristics of patients with OM attending a tertiary care hospital in Delhi. Hundred patients with clinical diagnosis of OM were recruited. Among these, 88 patients who tested positive for OM on direct microscopy with KOH, culture and/or histopathology with periodic acid-Schiff were included in the study. The clinico-mycological characteristics and risk factors associated with OM were evaluated. OM was more common in males (M:F = 2.5:1). The mean age of patients with OM was 39 ± 15.3 years (SE 1.52) with mean disease duration of 27.6 ± 46.1 months (SE 4.9). Seventeen (19.3%) patients had concomitant diabetes mellitus. The patients displayed mean body mass index (BMI) of 25.67 ± 1.35 kg/sq m. Concurrent dermatophytosis of skin was present in 35 (39.77%) patients. Two feet-one hand syndrome was present in 5 patients. Fingernail involvement without toenail involvement was more common than toenail involvement alone. (43.18% vs 38.63%). Distal and lateral subungual OM (DLSO) was the commonest clinical variant (81.8%). Mycological culture showed growth in 47 (53.40%) patients. Dermatophytes were isolated in majority, that is in 30 (63.82%) patients followed by non-dermatophytic moulds (NDM) in 7 (14.8%) and Candida spp. in the remaining 10 (21.27%) patients.

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.

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.

Dermatomycoses in the Israeli defense forces-Epidemiological and clinical aspects.

Dermatomycoses, involving skin, hair and nail infections, are among the most frequent human infections with global distribution and may have a public health and economic impact. The causative agents include Dermatophytes, Candida, Malassezia and non-Dermatophyte moulds. High morbidity may be associated with certain variables: age, gender, occupation-such as farming or military service, and climate or environmental conditions. The objectives of the present study included: (a). Assessment of epidemiological aspects of dermatomycoses in the Israeli Defense Forces (IDF). (b). Antifungal drug susceptibility of fungi isolated in culture from soldiers. (a) Epidemiological assessment: data based on IDF's medical registry during the period 2009-2013 on 10 831 male and female soldiers (8164 and 2667, respectively), of which 2589 were combat soldiers. (b) Susceptibility tests: to ketoconazole, fluconazole, itraconazole, terbinafine and griseofulvin of ~ 100 Dermatophyte and Candida isolates, using E test and/or disc diffusion assays. (c) Statistical analysis: logistic regression, chi-square and ANOVA. (a) Incidence in male soldiers higher than in female soldiers (35% vs. 28%). (b) Incidence in combat soldiers higher than in non-combat soldiers (39% vs 32%). (c) The major site of involvement-nails. (d) Infections peaked during summer months. (e) Dermatophytes constitute close to 90% of the aetiological agents (87% and 86%). (f) Trichophyton rubrum the dominant species. (g) terbinafine was the most active antifungal drug. The most significant conclusion of relevance of this study is the finding of higher morbidity rate among combat soldiers, as this may affect the activity of this group.

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.

Ciclopirox and Efinaconazole Transungual Permeation, Antifungal Activity, and Proficiency To Induce Resistance in Trichophyton rubrum.

Onychomycosis is a nail fungal infection, mostly caused by dermatophytes. The treatment efficacy is impaired by difficulties of reaching effective drug levels at the site of infection; frequent relapses occur after cessation of antifungal therapy. The aim of the study was to compare two commercial products containing ciclopirox or efinaconazole for antimycotic activity and antifungal drug resistance. A study of permeation and penetration through bovine hoof membranes, as a nail model, was performed to evaluate the antimycotic activity of permeates against clinical isolates of selected fungi, and the frequency of spontaneous in vitroTrichophyton rubrum-resistant strains was assessed by broth microdilution assays. The results suggest that ciclopirox creates a depot in the nail, leading to a gradual release of the drug over time with action on both the nail plate and bed. Conversely, efinaconazole, mildly interacting with nail keratin, mainly exerts its antifungal activity in the nail bed. However, in the case of T. rubrum, the antifungal activities of the drugs in the nail plate seem comparable. Finally, efinaconazole showed a potential for induction of resistance in T. rubrum, which may limit its efficacy over time. Ciclopirox did not show any potential to induce resistance in T. rubrum and appears endowed with a more complete activity than efinaconazole in the management of onychomycosis as the nail keratin is a substrate for the growth of fungal cells, and the availability of drug in large concentration just in the nail bed may not be sufficient to guarantee the complete eradication of pathogens.

Species Distinction in the Trichophyton rubrum Complex.

The Trichophyton rubrum species complex comprises commonly encountered dermatophytic fungi with a worldwide distribution. The members of the complex usually have distinct phenotypes in culture and cause different clinical symptoms, despite high genome similarity. In order to better delimit the species within the complex, molecular, phenotypic, and physiological characteristics were combined to reestablish a natural species concept. Three groups, T. rubrum, T. soudanense, and T. violaceum, could be distinguished based on the sequence of the internal transcribed spacer (ITS) ribosomal DNA barcode gene. On average, strains within each group were similar by colony appearance, microscopy, and physiology, but strains between groups showed significant differences. Trichophyton rubrum strains had higher keratinase activity, whereas T. violaceum strains tended to be more lipophilic; however, none of the phenotypic features were diagnostic. The results of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and amplified fragment length polymorphism (AFLP) were partially consistent with the ITS data but failed to distinguish the species unambiguously. Despite their close similarity, T. violaceum, T. soudanense, and T. rubrum can be regarded as independent species with distinct geographical distributions and clinical predilections. Trichophyton soudanense is pheno- and genotypically intermediate between T. rubrum and T. violaceum For routine diagnostics, ITS sequencing is recommended.

Development and evaluation of a pan-dermatophyte polymerase chain reaction with species-level identification using sloppy molecular beacon probes.

BACKGROUND: Conventional laboratory diagnosis of dermatophyte infection is cumbersome and time-consuming. OBJECTIVES: We aimed to establish a simple, robust and rapid molecular diagnostic assay for the detection of dermatophytes and optionally nondermatophytes in clinical specimens. MATERIALS AND METHODS: We developed a two-tube pan-dermatophyte polymerase chain reaction (PCR) assay using six sloppy molecular beacon (SMB) probes. The first PCR uses dermatophyte-specific primers and enables detection and identification of most dermatophyte species. The second PCR with pan-fungal primers allows further differentiation of Trichophyton interdigitale and T. mentagrophytes/T. quinckeanum, T. violaceum and T. soudanense, and T. tonsurans and T. equinum, and detection of nondermatophytes. The test was evaluated with 306 clinical specimens by comparing it with the results of microscopy and culture. RESULTS: In melting-curve analyses, species-specific melting temperature signatures of the SMBs were defined, and thus, our new PCR enabled detection and species-level identification of at least 19 dermatophyte species. Sensitivity and specificity of PCR for detection of dermatophytes in clinical samples were estimated to be 96·9% and 90·4%, for culture 46·7% and 98·7%, and for microscopy 91·4% and 84·0%, respectively. The detection of nondermatophytes by PCR and culture did not correlate. CONCLUSIONS: The new assay showed excellent performance characteristics for the detection of dermatophytes and is significantly faster than culturing techniques, which makes it very promising for routine diagnostics of dermatophytosis. We noted that the detection of nondermatophytes in our assay currently has no benefit.

A single typical trichoscopic feature is predictive of tinea capitis: a prospective multicentre study.

BACKGROUND: Specific trichoscopic signs of tinea capitis (TC) were first described in 2008. The accuracy of this diagnostic tool has not been evaluated. OBJECTIVES: To assess the diagnostic accuracy of trichoscopy. METHODS: A prospective, multicentre study was done between March 2015 and March 2017 at the dermatology departments of four French university medical centres. Patients with a presumed diagnosis of TC were included. Trichoscopy was considered to be positive if at least one specific trichoscopic sign was observed. Trichoscopy results were compared with the gold standard for diagnosis of TC (mycological culture). RESULTS: One hundred patients were included. Culture was positive for 53 patients and negative for 47. The sensitivity of trichoscopy was 94% [95% confidence interval (CI) 88-100], specificity was 83% (95% CI 72-94), positive predictive value was 92% and negative predictive value was 86%. Comma hairs, corkscrew hairs, zigzag hairs, Morse-code-like hairs and whitish sheath were significantly more frequent in patients with a positive mycological culture (P < 0·001). Comma hairs were more frequent in patients with Trichophyton TC (P = 0·026), and zigzag hairs were more frequent in patients with Microsporum TC (P < 0·001). Morse-code-like hair was not observed in any patients with Trichophyton TC and therefore appears to be highly specific for Microsporum TC. CONCLUSIONS: The presence of a single trichoscopic finding is predictive of TC. Trichoscopy is a useful, rapid, painless, highly sensitive tool for the diagnosis of TC - even for dermoscopists with little experience of trichoscopy. It enhances physicians' ability to make treatment decisions. What's already known about this topic? Tinea capitis (TC) must be confirmed by a mycological culture that may take up to 6 weeks, delaying treatment. Specific trichoscopic signs of TC were first described in 2008, but the accuracy of trichoscopy for diagnosing TC has not previously been evaluated. What does this study add? The present series is the largest yet on the use of trichoscopy in the diagnosis of TC. Our results demonstrated that the presence of a single feature (comma hair, corkscrew hair, zigzag hair, Morse-code-like hair or whitish sheath) is predictive of TC. Trichoscopy is painless and highly sensitive. Morse-code-like hair appears to be highly specific for Microsporum TC.

Infrared spectroscopy as a novel tool to diagnose onychomycosis.

BACKGROUND: The determination of causative organisms of onychomycosis is still not optimal. There remains a need for a cheap, fast and easy-to-perform diagnostic tool with a high capacity to distinguish between organisms. OBJECTIVES: To determine whether attenuated total-reflectance Fourier transform infrared (ATR-FTIR) spectroscopy can detect and differentiate causative agents in culture-based, ex vivo nail and in vivo nail models. METHODS: A methodological study was conducted. Both the ex vivo nail model and in vivo pilot study were carried out in an academic university hospital. RESULTS: Analysis of cultured fungi revealed spectral differences for dermatophytes (1692-1606 and 1044-1004 cm-1 ) and nondermatophytes and yeasts (973-937 cm-1 ), confirmed by dendrograms showing an excellent separation between samples from different genera or species. Exploration of dermatophytes, nondermatophytes and yeasts growing on ex vivo nails exposed prominent differences from 1200 to 900 cm-1 . Prediction models resulted in a 96·9% accurate classification of uninfected nails and nails infected with dermatophytes, nondermatophytes and yeasts. Overall correct classification rates of 91·0%, 97·7% and 98·6% were obtained for discrimination between dermatophyte, nondermatophyte and yeast genera or species, respectively. Spectra of in vivo infected and uninfected nails also revealed distinct spectral differences (3000-2811 cm-1 , 1043-950 cm-1 and 1676-1553 cm-1 ), illustrated by two main clusters (uninfected vs. infected) on a dendrogram. CONCLUSIONS: Our data suggest that ATR-FTIR spectroscopy may be a promising, fast and accurate method to determine onychomycosis, including identification of the causative organism, bypassing the need for lengthy fungal cultures.