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1.
Cancers (Basel) ; 16(3)2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38339329

ABSTRACT

BACKGROUND: Teledermatology is employed in the diagnosis and follow-up of skin cancer and its use was intensified during and after the COVID-19 pandemic. At the same time, demographic changes result in an overall increase in non-melanoma skin cancer and skin precancerous lesions. The aim of this study was to elucidate the role of teledermatology in comparison to conventional face-to-face dermatology for such lesions and determine the advantages and limitations of this workflow for patients and physicians. METHODS: Research was performed using relevant keywords in MEDLINE and CENTRAL. Relevant articles were chosen following a predetermined standardized extraction form. RESULTS: Diagnostic accuracy and interrater/intrarater agreement can be considered comparable-although lower-than in-person consultation. Improvement of particular features such as image quality, medical history availability, and teledermoscopy can further increase accuracy. Further aspects of limitations and advantages (mean time-to-assessment, time-to-treatment, cost-effectiveness) are discussed. CONCLUSIONS: Teledermatology has comparable diagnostic accuracy with face-to-face dermatology and can be utilized both for the effective triage of non-melanocytic epithelial tumors and precancerous lesions, as well as the follow-up. Easy access to dermatologic consultation with shorter mean times to diagnostic biopsy and/or treatment coupled with cost-effectiveness could compensate for the lower sensitivity of teledermatology and offer easier access to medical care to the affected populations.

2.
Acta Derm Venereol ; 103: adv00868, 2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36789756

ABSTRACT

Dandruff is a common scalp disorder with multiple microbial and host-related factors contributing to its aetiology, including alterations in scalp sebum. Despite existing evidence that the yeast Malassezia restricta plays a key role in the onset of dandruff, the interplay of these factors is poorly understood. Recently, squalene monohydroperoxide and malondialdehyde were established as biomarkers of dandruff-afflicted scalp, highlighting the role of sebum lipoperoxidation in the triggering and maintenance of dandruff, although its mechanism of action is unknown. The current study provides evidence that M. restricta mediates sebum peroxidation, leading to production of squalene monohydroperoxide and malondialdehyde. Furthermore, in vitro data show that these lipoperoxidation products act on epidermal cells and alter the skin barrier. These results support the role of Malassezia restricta-induced lipoperoxides as triggers of dandruff, which suggests that blocking their production could be a novel anti-dandruff treatment approach.


Subject(s)
Dandruff , Malassezia , Humans , Dandruff/drug therapy , Dandruff/etiology , Malondialdehyde
3.
Dermatol Reports ; 15(4): 9761, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38348421

ABSTRACT

Bleomycin, an antineoplastic antibiotic that inhibits DNA synthesis, is used to treat various malignant tumors such as Hodgkin's lymphoma, squamous cell carcinoma, and germ cell tumors. Flagellate erythema is a rare rash with a linear pattern that has been observed in association with bleomycin treatment. Herein, we present a 43-year-old patient with metastatic testicular cell neoplasms who developed a whiplash rash during treatment with a chemotherapy regimen that included bleomycin. A typical case of bleomycin-related flagellate dermatitis has been diagnosed and the main features of this characteristic adverse drug event are briefly discussed.

4.
Cancers (Basel) ; 13(24)2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34944920

ABSTRACT

Malignant melanomas resembling seborrheic keratosis (SK-like MMs) are atypical, challenging to diagnose melanoma cases that carry the risk of delayed diagnosis and inadequate treatment. On the other hand, SK may mimic melanoma, producing a 'false positive' with unnecessary lesion excisions. The present study proposes a computer-based approach using dermoscopy images for the characterization of SΚ-like MMs. Dermoscopic images were retrieved from the International Skin Imaging Collaboration archive. Exploiting image embeddings from pretrained convolutional network VGG16, we trained a support vector machine (SVM) classification model on a data set of 667 images. SVM optimal hyperparameter selection was carried out using the Bayesian optimization method. The classifier was tested on an independent data set of 311 images with atypical appearance: MMs had an absence of pigmented network and had an existence of milia-like cysts. SK lacked milia-like cysts and had a pigmented network. Atypical MMs were characterized with a sensitivity and specificity of 78.6% and 84.5%, respectively. The advent of deep learning in image recognition has attracted the interest of computer science towards improved skin lesion diagnosis. Open-source, public access archives of skin images empower further the implementation and validation of computer-based systems that might contribute significantly to complex clinical diagnostic problems such as the characterization of SK-like MMs.

5.
Article in English | MEDLINE | ID: mdl-32266163

ABSTRACT

Yeasts of the genus, Malassezia, formerly known as Pityrosporum, are lipophilic yeasts, which are a part of the normal skin flora (microbiome). Malassezia colonize the human skin after birth and must therefore, as commensals, be normally tolerated by the human immune system. The Malassezia yeasts also have a pathogenic potential where they can, under appropriate conditions, invade the stratum corneum and interact with the host immune system, both directly but also through chemical mediators. The species distribution on the skin and the pathogenetic potential of the yeast varies between different Malassezia related diseases such as head and neck dermatitis, seborrheic dermatitis, pityriasis versicolor, and Malassezia folliculitis. The diagnostic methods used to confirm the presence of Malassezia yeasts include direct microcopy, culture based methods (often a combination of morphological features of the isolate combined with biochemical test), molecular based methods such as Polymerase Chain Reaction techniques, and Matrix Assisted Laser Desorption/Ionization-Time Of Flight mass spectrometry and the chemical imprint method Raman spectroscopy. Skin diseases caused by Malassezia are usually treated with antifungal therapy and if there are associated inflammatory skin mechanisms this is often supplemented by anti-inflammatory therapy. The aim of this paper is to provide an overview of Malassezia related skin disease, diagnostic methods and treatment options.


Subject(s)
Dermatitis, Seborrheic , Folliculitis , Malassezia , Tinea Versicolor , Dermatitis, Seborrheic/diagnosis , Dermatitis, Seborrheic/drug therapy , Folliculitis/diagnosis , Folliculitis/drug therapy , Humans , Skin , Tinea Versicolor/diagnosis , Tinea Versicolor/drug therapy
6.
J Invest Dermatol ; 133(8): 2023-30, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23448877

ABSTRACT

Malassezia yeasts are commensal microorganisms, which under insufficiently understood conditions can become pathogenic. We have previously shown that specific strains isolated from diseased human skin can preferentially produce agonists of the aryl hydrocarbon receptor (AhR), whose activation has been linked to certain skin diseases. Investigation of skin scale extracts from patients with Malassezia-associated diseases demonstrated 10- to 1,000-fold higher AhR-activating capacity than control skin extracts. Liquid chromatography-tandem mass spectrometry analysis of the patients' extracts revealed the presence of indirubin, 6-formylindolo[3,2-b]carbazole (FICZ), indolo[3,2-b]carbazole (ICZ), malassezin, and pityriacitrin. The same compounds were also identified in 9 out of 12 Malassezia species culture extracts tested, connecting their presence in skin scales with this yeast. Studying the activity of the Malassezia culture extracts and pure metabolites in HaCaT cells by reverse transcriptase real-time PCR revealed significant alterations in mRNA levels of the endogenous AhR-responsive genes Cyp1A1, Cyp1B1, and AhRR. Indirubin- and FICZ-activated AhR in HaCaT and human HepG2 cells with significantly higher, yet transient, potency as compared with the prototypical AhR ligand, dioxin. In loco synthesis of these highly potent AhR inducers by Malassezia yeasts could have a significant impact on skin homeostatic mechanisms and disease development.


Subject(s)
Dermatomycoses/microbiology , Malassezia/growth & development , Malassezia/metabolism , Receptors, Aryl Hydrocarbon/metabolism , Skin/microbiology , Carcinoma, Hepatocellular , Cell Extracts , Cell Line, Transformed , Cell Line, Tumor , Cytochrome P-450 CYP1A1/genetics , Cytochrome P-450 CYP1A1/metabolism , Dermatomycoses/metabolism , Dermatomycoses/pathology , Homeostasis/physiology , Humans , Indoles/metabolism , Keratinocytes/cytology , Keratinocytes/microbiology , Liver Neoplasms , Malassezia/isolation & purification , RNA, Messenger/metabolism , Skin/metabolism
8.
J Invest Dermatol ; 132(3 Pt 1): 575-82, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22089833

ABSTRACT

Netherton syndrome (NS) is a severe skin disease caused by loss-of-function mutations in SPINK5 (serine protease inhibitor Kazal-type 5) encoding the serine protease inhibitor LEKTI (lympho-epithelial Kazal type-related inhibitor). Here, we disclose new SPINK5 defects in 12 patients, who presented a clinical triad suggestive of NS with variations in inter- and intra-familial disease expression. We identified a new and frequent synonymous mutation c.891C>T (p.Cys297Cys) in exon 11 of the 12 NS patients. This mutation disrupts an exonic splicing enhancer sequence and causes out-of-frame skipping of exon 11. Haplotype analysis indicates that this mutation is a founder mutation in Greece. Two other new deep intronic mutations, c.283-12T>A in intron 4 and c.1820+53G>A in intron 19, induced partial intronic sequence retention. A new nonsense c.2557C>T (p.Arg853X) mutation was also identified. All mutations led to a premature termination codon resulting in no detectable LEKTI on skin sections. Two patients with deep intronic mutations showed residual LEKTI fragments in cultured keratinocytes. These fragments retained some functional activity, and could therefore, together with other determinants, contribute to modulate the disease phenotype. This new founder mutation, the most frequent mutation described in European populations so far, and these unusual intronic mutations, widen the clinical and molecular spectrum of NS and offer new diagnostic perspectives for NS patients.


Subject(s)
Founder Effect , Introns/genetics , Mutation , Netherton Syndrome/diagnosis , Netherton Syndrome/genetics , Proteinase Inhibitory Proteins, Secretory/genetics , RNA Splicing/genetics , Adolescent , Adult , Base Sequence , Child , Child, Preschool , Codon, Nonsense/genetics , Exons/genetics , Female , Humans , Infant , Male , Molecular Sequence Data , Serine Peptidase Inhibitor Kazal-Type 5
9.
Curr Opin Infect Dis ; 22(2): 119-25, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19283910

ABSTRACT

PURPOSE OF REVIEW: The recent sequencing of the whole genome of Malassezia globosa and M. restricta forms the basis for molecular epidemiology studies and instigates investigations into their respective virulence factors. Thus, reviewing current knowledge on Malassezia molecular typing methods would reveal the pros and cons of each method and would highlight potential scarcity of epidemiological data regarding this ubiquitous fungal commensal and pathogen. RECENT FINDINGS: Methods employed for Malassezia molecular typing can be categorized into those detecting sequence variations of strains and those that selectively amplify polymorphic DNA markers for discriminating Malassezia species subtypes. The former exploit rRNA gene sequence variations in order to trace M. globosa, M. restricta and M.pachydermatis subtypes associated with specific skin diseases, or detect M. furfur geographical variations. Polymorphic DNA amplification methods, such as amplified fragment length polymorphism analysis, demonstrated association of M. furfur subtypes with the origin of the strain (skin or systemic isolate), whereas PCR-fingerprinting of the mini-satellite DNA clustered M. furfur strains according to their geographic origin and disease origin. Moreover, much typing work has already been performed regarding the zoophilic species M. pachydermatis and the relevant methods can be adapted for studying the anthropophilic Malassezia species. SUMMARY: In the near future, molecular typing will be a powerful tool in epidemiological studies that could be employed for the elucidation of the pathobiology of Malassezia species in associated skin diseases


Subject(s)
Dermatomycoses/epidemiology , Dermatomycoses/microbiology , Malassezia/classification , Malassezia/genetics , Mycological Typing Techniques , Polymorphism, Genetic , DNA Fingerprinting , DNA, Fungal/genetics , Genotype , Humans , Malassezia/isolation & purification
10.
ISME J ; 3(4): 498-502, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19020555

ABSTRACT

Malassezia furfur was the first species described within the cosmopolitan yeast genus Malassezia, which now comprises 13 species. Reported isolation rates of these species from healthy and diseased human skin show geographic variations. PCR-fingerprinting with the wild-type phage M13 primer (5'-GAGGGTGGCGGTTCT-3') was applied to investigate phylogeographic associations of M. furfur strains isolated from Scandinavians residing permanently in Greece, in comparison to clinical isolates from Greek, Bulgarian and Chinese native residents. Seven M. furfur strains from Scandinavians were compared with the Neotype strain (CBS1878), CBS global collection strains (n=10) and clinical isolates from Greece (n=4), Bulgaria (n=15) and China (n=6). Scandinavian, Greek and Bulgarian M. furfur strains mostly formed distinct group clusters, providing initial evidence for an association with the host's geographical origin and with the underlying skin condition. These initial data address the hypothesis that M. furfur could be a eukaryotic candidate eligible for phylogeographic studies.


Subject(s)
DNA Fingerprinting/methods , Dermatomycoses/epidemiology , Dermatomycoses/microbiology , Malassezia/classification , Malassezia/genetics , Mycological Typing Techniques/methods , Random Amplified Polymorphic DNA Technique/methods , Adolescent , Adult , Bacteriophage M13/genetics , Bulgaria , Child , Child, Preschool , China , Cluster Analysis , DNA Primers , DNA, Fungal/genetics , Female , Genotype , Geography , Greece , Humans , Infant , Male , Middle Aged , Young Adult
12.
J Invest Dermatol ; 128(7): 1620-5, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18219281

ABSTRACT

Malassezia yeasts are connected with seborrheic dermatitis (SD) whereas M. furfur pathogenicity is associated with the production of bioactive indoles. In this study, the production of indoles by M. furfur isolates from healthy and diseased skin was compared, the respective HPLC patterns were analyzed, and substances that are preferentially synthesized by strains isolated from SD lesions were isolated and characterized. Malassezin, pityriacitrin, indole-3-carbaldehyde, and indolo[3,2-b]carbazole (ICZ) were isolated by HPLC from extracts of M. furfur grown in L-tryptophan agar, and identified by nuclear magnetic resonance and mass spectroscopy. Of these, ICZ, a potent ligand of the aryl hydrocarbon receptor (AhR), is described for the first time to our knowledge as a M. furfur metabolite. HPLC-photodiode array detection analysis of strain extracts from 7 healthy subjects and 10 SD patients showed that M. furfur isolates from only SD patients consistently produce malassezin and ICZ. This discriminatory production of AhR agonists provides initial evidence for a previously unreported mechanism triggering development of SD and indicates that the variable pathogenicity patterns recorded for M. furfur-associated SD conditions may be attributed to selective production (P<0.001) of measurable bioactive indoles.


Subject(s)
Carbazoles/metabolism , Dermatitis, Seborrheic/microbiology , Indoles/metabolism , Malassezia/metabolism , Receptors, Aryl Hydrocarbon/metabolism , Skin/microbiology , Carbazoles/chemistry , Chromatography, High Pressure Liquid , Humans , Indoles/chemistry , Ligands
14.
J Clin Microbiol ; 43(8): 4147-51, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16081962

ABSTRACT

Melanin-like pigment produced in vitro and in vivo by Malassezia yeasts has not been described before. Masson-Fontana staining confirmed accumulation of black pigment on the cell walls of L-dihydroxyphenylalaline (L-DOPA)-cultured Malassezia species. Black pigment was also observed in cells and hyphae from hyperpigmented patient lesions with culture-confirmed pityriasis versicolor and seborrheic dermatitis.


Subject(s)
Malassezia/metabolism , Melanins/biosynthesis , Silver Nitrate , Humans , Levodopa/metabolism , Melanins/analysis , Oxidation-Reduction
16.
J Clin Microbiol ; 42(8): 3589-93, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15297502

ABSTRACT

A novel formulation of RPMI 1640 medium for susceptibility testing of Malassezia yeasts by broth microdilution (BMD) and Etest is proposed. A modification of the NCCLS M27-A2 BMD method was used to test 53 isolates of Malassezia furfur (12 isolates), M. sympodialis (8 isolates), M. slooffiae (4 isolates), M. globosa (22 isolates), M. obtusa (2 isolates), M. restricta (2 isolates), M. pachydermatis (1 isolates), and M. dermatis (2 isolates) against amphotericin B, ketoconazole, itraconazole, fluconazole, voriconazole, terbinafine, and posaconazole by BMD and Etest. RPMI and antibiotic medium 3 (AM3) were supplemented with glucose, bile salts, a mixture of fatty acids, and n-octadecanoate fatty acids and Tween 20. M. furfur ATCC 14521 and M. globosa ATCC 96807 were used as quality control strains. Depending on the species, MICs were read after 48 or 72 h of incubation at 32 degrees C. Low azole and terbinafine MICs were recorded for all Malassezia species, whereas amphotericin B displayed higher MICs (>/=16 microg/ml) against M. furfur, M. restricta, M. globosa, and M. slooffiae strains, which were AM3 confirmed. Agreement of the two methods was 84 to 97%, and intraclass correlation coefficients were statistically significant (P < 0.001). Because of higher amphotericin B MICs provided by Etest for strains also displaying high BMD MICs (>/=1 microg/ml), agreement was poorer. The proposed media are used for the first time and can support optimum growth of eight Malassezia species for recording concordant BMD and Etest MICs.


Subject(s)
Antifungal Agents/pharmacology , Malassezia/drug effects , Triazoles/pharmacology , Culture Media , Fatty Acids , Humans , Microbial Sensitivity Tests , Mycoses/epidemiology , Mycoses/microbiology
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