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1.
J Med Case Rep ; 18(1): 431, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39285486

ABSTRACT

BACKGROUND: Tinea versicolor is a very common condition. We reported a specific follicular manifestation and proposed that this particular presentation might be related to the patient's history of previous keratosis pilaris. CASE PRESENTATION: A 46-year-old Asian woman of Han ethnicity presented to the clinic with trunk lesions for over a year. On physical examination: multiple light brown patches of varying size centered on hair follicles in the axillae and trunk, with the patches on the back fusing together and scales visible on the surface of the patches. Finally, through fungal microscopy and pathological examination, the patient was diagnosed with folliculocentric tinea versicolor. CONCLUSIONS: Follicular tinea versicolor is a rare type of tinea versicolor. It is still not clear what causes tinea versicolor to become folliculocentric. This case may suggest that patients with a history of keratosis pilaris may have a tendency to develop follicular centration in the course of other diseases.


Subject(s)
Tinea Versicolor , Humans , Female , Middle Aged , Tinea Versicolor/diagnosis , Tinea Versicolor/drug therapy , Antifungal Agents/therapeutic use , Hair Follicle/pathology , Darier Disease/diagnosis , Darier Disease/pathology , Abnormalities, Multiple , Eyebrows/abnormalities
2.
Arch Dermatol Res ; 316(8): 501, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39093484

ABSTRACT

The goal of this study is to investigate the impact of the rs35829419 SNP on the serum level of NLRP3, and to assess the relationship between NLRP3 and its SNP and vulnerability to Pityriasis versicolor. Pityriasis versicolor (PV) is one of the most frequent skin conditions linked to skin pigmentation changes. Malassezia plays a key role in the pathogenesis of PV. A case-control study, 50 patients with pityriasis versicolor and 44 healthy controls. Real-time PCR was used to genotype NLRP3 (rs35829419) and ELISA assay of NLRP3 levels in tissue samples. There was a significantly higher median NLPR3 levels in PV patients than controls. A significant predominance of A allele of Q 705 K was in patients than controls. The risk of having the disease in the presence of A allele is nearly 10 times than having C allele. In PV patients, there was a significant relationship between NLPR3 levels and Q 705 K genotypes with higher NLPR3 levels in AA genotype. A potential correlation between PV and the Q705K polymorphism, pointing to evidence of NLRP3 alteration in PV patients. The NLRP3 inflammasome may be an appropriate therapeutic target for Malassezia-associated skin disorders.


Subject(s)
Genotype , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Polymorphism, Single Nucleotide , Skin , Tinea Versicolor , Humans , Tinea Versicolor/diagnosis , Tinea Versicolor/genetics , Tinea Versicolor/microbiology , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Female , Male , Case-Control Studies , Adult , Inflammasomes/genetics , Inflammasomes/metabolism , Inflammasomes/immunology , Skin/pathology , Skin/microbiology , Malassezia/isolation & purification , Malassezia/immunology , Malassezia/genetics , Young Adult , Genetic Predisposition to Disease , Middle Aged , Alleles , Adolescent
3.
Mycoses ; 67(8): e13775, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39079943

ABSTRACT

BACKGROUND: Pityriasis versicolor (PV), a cutaneous fungal infection, most commonly affects adolescents and young adults and is associated with hyperhidrosis and humid weather. Understanding other factors associated with PV might help improve diagnostic and treatment practices. OBJECTIVES: PV's associations with patient demographics, comorbidities and medication exposures were assessed using the All of Us Database, a large, diverse, national database from the United States. METHODS: A case-control study with multivariable analysis was performed. RESULTS: We identified 456 PV case-patients and 1368 control-patients. PV case-patients (vs. control-patients) were younger (median age [years] (standard deviation): 48.7 (15.4) vs. 61.9 (15.5); OR: 0.95, CI: 0.94-0.96) and more likely to be men versus women (42.8% vs. 33.9%, OR: 1.45, CI: 1.16-1.79) and Black (19.5% vs. 15.8%, OR: 1.35, 95% CI: 1.02-1.80) or Asian (4.6% vs. 2.7%, OR: 1.86, CI: 1.07-3.24) versus White. PV case-patients more frequently had acne (5.3% vs. ≤1.5%, OR: 5.37, CI: 2.76-10.48) and less frequently had type 2 diabetes mellitus (T2DM) (14.7% vs. 24.7%, OR: 0.52, CI: 0.39-0.70) and hypothyroidism (OR: 10.3% vs. 16.4%, OR: 0.59, CI: 0.42-0.82). In multivariable analysis, PV odds were significantly higher in those with acne and lower in those with T2DM, older age and female sex. CONCLUSIONS: Our results may be used as a basis for future studies evaluating whether acne treatment may decrease PV risk. Physicians could educate patients with acne about PV, including strategies to control modifiable PV risk factors, such as avoidance of hot and humid environments and avoidance of use of topical skin oils.


Subject(s)
Databases, Factual , Tinea Versicolor , Humans , Male , Female , Tinea Versicolor/epidemiology , Tinea Versicolor/drug therapy , Case-Control Studies , Middle Aged , Adult , United States/epidemiology , Risk Factors , Aged , Young Adult , Adolescent , Comorbidity
4.
Phytomedicine ; 130: 155542, 2024 Jul 25.
Article in English | MEDLINE | ID: mdl-38823343

ABSTRACT

BACKGROUND: Malassezia globosa is a commensal basidiomycetous yeast occurring on the skin that causes pityriasis versicolor (PV) and seborrheic dermatitis, but that has also been implicated in other dermatoses. Cinnamaldehyde (CM) has antibacterial, antioxidant, and anti-inflammatory activities, but the effect of CM on M. globosa-infected PV has not been clarified. PURPOSE: The study aimed to investigate the possible antifungal and antibiofilm activities of CM against M. globosa-infected PV in vivo and in vitro. METHODS: The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of CM against M. globosa. The crystal violet staining assay and XTT assay were used to investigate the inhibition of CM on biofilm formation and the eradication of mature biofilms. The visualizations of the biofilm and cell distribution in the biofilm matrix were performed with a scanning electron microscope and confocal laser scanning microscope. The kits of antioxidant kinase were used to determine the activities of oxidative stress markers in M. globosa-stimulated HaCaT cells. Western blot assays were used to evaluate the role of TLR2/NF-κB in vitro. Furthermore, the protective effect of CM was assessed in M. globosa-associated PV mice. The expressions of inflammatory cytokines and apoptosis were screened using ELISA assays. The expressions of interleukin-6 and tumor necrosis factor-α were measured by an immunohistochemistry method in vivo. RESULTS: Our results showed that the MIC of CM against planktonic cells of M. globosa was 4 µg/ml and treatment with 20 × MIC CM eradicated mature biofilms of M. globosa. In vitro, after CM treatment the levels of oxidative stress indicators (i.e., superoxide dismutase, catalase, glutathione) significantly increased, while the levels of malondialdehyde decreased. In addition, the expression of TLR2/NF-κB in HaCaT cells was significantly reduced after CM treatment. On the other hand, an in vivo therapeutic effect of CM was assessed against M. globosa-infected mice. The fungal load on the skin decreased after treatment with CM compared to the M. globosa-infected group. In addition, the uninfected animals showed a normal skin structure, whereas, the M. globosa-infected mice showed extensive infiltration of neutrophils in skin tissues that improved after treatment with CM. Meanwhile, the levels of inflammatory and apoptotic factors improved after CM treatment. CONCLUSION: Our results showed that CM inhibits the biofilm formation of M. globosa and eradicates mature biofilms of M. globosa. Treatment with CM significantly decreased oxidative stress, apoptosis, and inflammatory markers in the skin tissue and HaCaT cells. Hence, this study suggests that CM is a good candidate therapeutic agent against M. globosa-induced PV infections because of its antifungal, antibiofilm, and anti-inflammatory properties.


Subject(s)
Acrolein , Antifungal Agents , Biofilms , Malassezia , Microbial Sensitivity Tests , Tinea Versicolor , Toll-Like Receptor 2 , Biofilms/drug effects , Acrolein/analogs & derivatives , Acrolein/pharmacology , Animals , Malassezia/drug effects , Humans , Toll-Like Receptor 2/metabolism , Tinea Versicolor/drug therapy , Antifungal Agents/pharmacology , Mice , Oxidative Stress/drug effects , HaCaT Cells , NF-kappa B/metabolism , Interleukin-6/metabolism , Antioxidants/pharmacology , Tumor Necrosis Factor-alpha/metabolism , Skin/drug effects , Skin/microbiology
8.
Acta Medica Philippina ; : 64-78, 2024.
Article in English | WPRIM (Western Pacific) | ID: wpr-1006405

ABSTRACT

Background@#Pityriasis versicolor is a common fungal infection of the superficial skin layer caused by Malassezia furfur, a normal commensal in the skin. Keratolytic agents are popular, cheap, and readily available over-the-counter treatments for pityriasis versicolor. Conventional antifungal agents are more expensive, requiring prescription, and may induce resistant strains. However, evidence of their comparative safety and efficacy is still lacking. @*Objectives@#To assess the efficacy and safety of synthetic antifungals compared to keratolytic agents in the topical treatment of pityriasis versicolor through a systematic review.@*Methods@#We searched the following databases: MEDLINE (from 1966) through PubMed, CENTRAL (Issue 9 of 12, September 2021), EMBASE (from 1974), LILACS (from 1987); Herdin (from 1970), www.clinicaltrials.gov, www. isrctn.com, www.trialregister.nl. We contacted researchers in the field, hand searched relevant conference abstracts, and the Journal of the Philippine Dermatological Society 1992-2019. We included all randomized controlled trials involving patients with diagnosed active pityriasis versicolor where topical antifungal was compared with a topical keratolytic for treatment. Two review authors independently applied eligibility criteria, assessed risk of bias using the Cochrane collaboration tool, and extracted data from included studies. We used RevMan 5.3 to pool dichotomous outcomes using risk ratios (RR) and continuous outcomes using the mean difference (MD), using random-effects meta-analysis. We tested for statistical heterogeneity using both the Chi² test and the I² test. We presented results using forest plots with 95% confidence intervals. We planned to create a funnel plot to determine publication bias but were unable to due to few studies. A Summary of Findings table was created using GRADE profile software for the primary outcomes. @*Results@#We included 8 RCTs with a total of 617 participants that compared azole preparations (ketoconazole, bifonazole and econazole) versus keratolytic agents (selenium sulfide, adapalene, salicylic-benzoic acid). Pooled data showed that azoles did not significantly differ from keratolytic agents for clinical cure (RR 0.99, 0.88, 1.12; 4 RCTs, N=274, I2=55%; very low-quality evidence), and adverse events (0.59 [0.17, 2.06]; very low-quality evidence) based on 6 RCTs (N=536). There were two patients given a keratolytic agent (selenium sulfide shampoo) who had acute dermatitis and discontinued treatment. @*Conclusion@#It is uncertain whether topical azoles are as effective as keratolytic agents in clinical clearance and occurrence of adverse events in patients with pityriasis versicolor. A wider search of grey literature and local studies are warranted. Larger RCTs with low risk of bias are recommended.


Subject(s)
Azoles , Tinea Versicolor
9.
Article in English | MEDLINE | ID: mdl-38155006

ABSTRACT

Malassezia is a lipid-dependent cutaneous symbiotic fungal genus associated with tinea versicolor. Here, we first present a rare case of a young tinea versicolor patient with oral manifestations presenting as white strips, patches, and pigmentation. The patient had a family history of tinea versicolor and a habit of frequent intake of cream. Histopathologic features and periodic acid-schiff staining of oral lesion indicated oral infection with round budding yeasts with short hyphae. Saliva metagenomic sequencing identified Malassezia and demonstrated the upregulated amount, diversity and activity of inflammatory bacteria. The clinical manifestations of oral Malassezia infection and changes in bacterial communities shed light on the pathogenic role of Malassezia in oral mucosa. In conclusion, we report the first oral Malassezia infection, which broadens the pathogenic cognitive scope of Malassezia and highlights the value of molecular techniques in the diagnostic process.


Subject(s)
Malassezia , Tinea Versicolor , Humans , Malassezia/genetics , Tinea Versicolor/diagnosis , Saliva , Mouth Mucosa
10.
Expert Rev Anti Infect Ther ; 21(12): 1327-1338, 2023.
Article in English | MEDLINE | ID: mdl-37883074

ABSTRACT

INTRODUCTION: Malassezia spp. are a group of lipid-dependent basidiomycetes yeasts acting as commensal organisms of the human and animal skin. However, under some not well-defined circumstances, these yeasts may switch to opportunistic pathogens triggering a number of skin disorders with different clinical presentations. The genus comprises of 18 lipid-dependent species with a variable distribution in the hosts and pathologies thus suggesting a host- and microbe-specific interactions. AREA COVERED: This review highlighted and discussed the most recent literature regarding the genus Malassezia as a commensal or pathogenic organisms highlighting Malassezia-associated skin disorders in humans and animals and their antifungal susceptibility profile. A literature search of Malassezia associated skin disorders was performed via PubMed and Google scholar (up to May 2023), using the different keywords mainly associated with Malassezia skin disorders and Malassezia antifungal resistance. EXPERT OPINION: Malassezia yeasts are part of the skin mycobiota and their life cycle is strictly associated with the environment in which they live. The biochemical, physiological, or immunological condition of the host skin selects Malassezia spp. or genotypes able to survive in a specific environment by changing their metabolisms, thus producing virulence factors or metabolites which can cause skin disorders with different clinical presentations.


Subject(s)
Dermatitis, Seborrheic , Dermatomycoses , Malassezia , Tinea Versicolor , Humans , Animals , Tinea Versicolor/drug therapy , Tinea Versicolor/microbiology , Tinea Versicolor/pathology , Dermatomycoses/drug therapy , Dermatomycoses/microbiology , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Dermatitis, Seborrheic/drug therapy , Dermatitis, Seborrheic/microbiology , Skin/microbiology , Skin/pathology , Lipids
11.
Mycoses ; 66(6): 540-549, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36840378

ABSTRACT

BACKGROUND: Malassezia furfur is a member of the human skin microbiomes that can cause various skin diseases. Dimorphism plays a role as the yeast phase predominates during skin colonisation whereas mycelial forms are observed in the scales of patients with pityriasis versicolor (PV). However, due to their condition-dependence for growth, it is difficult to culture M. furfur and this is an additional challenge for studying the pathogenicity of this fungus. OBJECTIVE: To describe different media suitable for culturing Malassezia from the yeast phase into mycelial forms, with a particular focus on nutritional supplements and pH conditions. METHODS: Clinical M. furfur isolates from patients with PV and healthy individuals were used to investigate Malassezia dimorphism as well as the activity and expression of lipase enzymes. RESULTS: Our experimental media were significantly more likely to promote mycelial growth in strains from healthy individuals compared to those from patients with PV. Lipase activity was increased in the mycelial phase cells compared to yeast forms for all strains tested. Assessment of the relative transcriptional expression of lipase within M. furfur revealed that LIP-coding genes were upregulated in mycelium relative to yeast forms for the strains tested. However, the increases in LIP3, LIP5 and LIP6 gene expressions were significantly greater in strains from healthy individuals compared to those from patients with PV. CONCLUSION: Overall, this study validated effective growth conditions to study M. furfur virulence factors and demonstrated that lipase is associated with M. furfur dimorphism.


Subject(s)
Malassezia , Tinea Versicolor , Humans , Tinea Versicolor/microbiology , Lipase/genetics , Lipase/metabolism , Virulence , Saccharomyces cerevisiae , Sex Characteristics
12.
Pediatr Dermatol ; 40(3): 578-579, 2023.
Article in English | MEDLINE | ID: mdl-36655624

ABSTRACT

Tinea versicolor (TV) is a fungal skin infection that classically affects adolescents and young adults. Occasionally, it may be seen on the face of infants. We report an unusual case of widespread cutaneous TV in a premature infant.


Subject(s)
Dermatomycoses , Tinea Versicolor , Infant , Adolescent , Young Adult , Humans , Infant, Newborn , Tinea Versicolor/diagnosis , Tinea Versicolor/drug therapy , Skin , Administration, Cutaneous , Infant, Premature
14.
Arch Dermatol Res ; 315(5): 1367-1374, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36449073

ABSTRACT

Recurrent and disseminated pityriasis versicolor (RDPV) is a common clinical entity, characterized by its recurrent and disfiguring nature. Studies demonstrated host genetic variations in the immune response, especially the role of IL-17 in antifungal immunity. This study aimed to detect whether IL-17A and F gene polymorphisms are found in cases of RDPV. It included 100 cases of RDPV and 100 age and sex matched controls, from which EDTA blood samples were taken for single-nucleotide polymorphism analysis. IL-17A (rs2275913) and F (rs763780) were associated with a significantly increased incidence of developing RDPV. IL-17A and F gene polymorphism could be implicated as a risk factor for the development of RDPV.


Subject(s)
Interleukin-17 , Tinea Versicolor , Humans , Polymorphism, Single Nucleotide , Case-Control Studies , Genetic Predisposition to Disease
15.
Pol J Microbiol ; 71(4): 529-538, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36473111

ABSTRACT

Seventy-seven strains of Malassezia were included in this study. Biofilm and hydrolytic enzyme production were studied by using specific solid media. The Real-Time reverse transcriptase qPCR method was applied to determine the overexpression of genes encoding the extracellular enzymes. All included Malassezia species produced biofilms. No statistically significant difference was observed between Malassezia species in biofilm formation (p = 0.567). All Malassezia species produced lipase, and 95% of Malassezia globosa showed a strong enzymatic activity (Pz = 0.55 ± 0.02). A statistically significant difference was observed between the mean keratinase indices of Malassezia slooffiae and the other Malassezia species (p = 0.005). The overexpression of one or more genes was observed in 100% of strains isolated from patients with folliculitis, 87.5% - with pityriasis versicolor, and 57.14% of the control group isolates. A statistically significant difference in the lipase gene expression (p = 0.042) was between the strains from patients with folliculitis and the control group. This investigation provides more information about the frequency of the production of the major enzymes considered virulence factors of Malassezia species. Interestingly, the overexpression of one or more genes was observed in strains isolated from patients with Malassezia disorders.


Subject(s)
Folliculitis , Malassezia , Tinea Versicolor , Humans , Malassezia/genetics , Virulence Factors , Lipase/metabolism
16.
Med Mycol J ; 63(3): 81-84, 2022.
Article in Japanese | MEDLINE | ID: mdl-36047187

ABSTRACT

Malassezia are lipophilic yeasts in the skin microbiome that abundantly colonize all parts of human skin except for the soles of the feet. Fungal microbiome analysis of keratotic plugs from the noses of 10 healthy individuals identified Malassezia restricta as the predominant species, followed by Malassezia globosa. Malassezia hyphae were observed in 5 of the 10 individuals. The hyphae were curved and thick-walled with spherical thick-walled and grouped blastoconidia, described as a "spaghetti-and-meatballs" configuration. In this study, we observed Malassezia hyphae in keratotic plugs of healthy subjects, although abundant Malassezia hyphae have previously only been observed in lesional sites of patients with pityriasis versicolor.


Subject(s)
Malassezia , Tinea Versicolor , Foot , Humans , Hyphae , Skin/microbiology , Tinea Versicolor/microbiology
17.
J Ethnopharmacol ; 298: 115603, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-35940465

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Pityriasis Versicolor (PV) is a commonly encountered infection of the skin caused by Malassezia species. Despite effective conventional antifungal drugs, the prevention and treatment of PV remain a challenge. The Unani pharmacopoeial preparations Itrifal Hakim Ali (IHA) and Habb-e-Kalaf (HK) have been used in the treatment of PV for a long time. The Unani practitioners recommend these formulations for the successful treatment of PV in clinical practice. AIM OF THE STUDY: This study aimed to evaluate the efficacy and safety of Unani formulations IHA (oral) and HK (topical) in the treatment of PV. MATERIALS AND METHODS: A single centre, randomized, active-controlled, parallel-group and open-label clinical study was carried out in the outpatient departments of the National Research Institute of Unani Medicine for Skin Disorders, Hyderabad, India. The participants diagnosed with PV of any gender aged between 18 and 60 years were randomized into the test group (n = 37) to receive oral IHA (10g/day) and topical HK and the active control group (n = 35) to receive oral Itraconazole (100 mg/day) and local Terbinafine (1%) for the period of 6 weeks. Of them, 30 participants in each group completed the duration of the protocol therapy. The outcome of this study was based on a per-protocol analysis of the data. The efficacy of the interventions was measured by post-treatment change in subjective clinical symptoms/signs, mean TSSS, IGA score, direct microscopy of fungal elements and DLQI. The dermal safety was assessed by Berger/Bowman Scoring Scale and systemic safety was evaluated by Urinalysis, haematological and biochemical parameters. RESULTS: This study observed statistically and clinically significant post-treatment reduction in itching (test group vs. active control group; 73.4% vs. 89.1%), hypopigmentation (63.2% vs. 57.1%), hyperpigmentation (60% vs. 65.5%), and scaling (91.6% vs. 92.7%) (p < 0.001). The differences in mean TSSS (5.4 ± 0.63 vs. 5.60 ± 0.32), IGA score (2.07 ± 0.15 vs. 1.74 ± 0.08) and DLQI (9.6 ± 2.06 vs. 9.04 ± 2.7) were also found clinically and statistically significant (p < 0.001) in each group when compared baseline data to post-treatment. On inter-group comparison, the changes in mean TSSS and DLQI were not found statistically significant at p < 0.05. But, the change in the mean IGA score was significant (p = 0.03). Further, the mycological cure was observed in 100% and 76.7% of participants in the test group and the control group respectively. On comparing inter-group the effects of the interventions on direct microscopy were found statistically significant (p = 0.034). In addition, no significant change in urinalysis, biochemical and haematological parameters from baseline to post-treatment in each group was observed. CONCLUSION: This study concluded that the test drugs (IHA and HK) were safe and effective in the treatment of PV. The oral (IHA) and local (HK) Unani formulations were tolerated well by all the participants The efficacy and safety of the IHA and HK were comparable to the standard drugs (Itraconazole and Terbinafine).


Subject(s)
Tinea Versicolor , Antifungal Agents/adverse effects , Child, Preschool , Humans , Immunoglobulin A , Infant , Itraconazole , Terbinafine/therapeutic use , Tinea Versicolor/drug therapy , Treatment Outcome
18.
Med Mycol ; 60(8)2022 Aug 30.
Article in English | MEDLINE | ID: mdl-35913746

ABSTRACT

Over the last decade, Malassezia species have emerged as increasingly important pathogens associated with a wide range of dermatological disorders and bloodstream infections. The pathogenesis of Malassezia yeasts is not completely clear, but it seems to be strictly related to Malassezia strains and hosts and needs to be better investigated. This study aimed to assess the enzymatic activities, biofilm formation and in vitro antifungal profiles of Malassezia spp. from pityriasis versicolor (PV) and healthy patients. The potential relationship between virulence attributes, the antifungal profiles and the origin of strains was also assessed. A total of 44 Malassezia strains isolated from patients with (n = 31) and without (n = 13) PV were employed to evaluate phospholipase (Pz), lipase (Lz), and hemolytic (Hz) activities and biofilm formation. In addition, in vitro antifungal susceptibility testing was conducted using the CLSI broth microdilution with some modifications. A high percentage of strains produced Pz, Lz, Hz and biofilm regardless of their clinical origin. The highest number of strains producing high enzymatic activities came from PV patients. A correlation between the intensity of hydrolytic activities (Lz and Pz activities) and the Hz activity was detected. Positive associations between Lz and the low fluconazole susceptibility and Hz and biofilm formation were observed. These results suggest that enzyme patterns and biofilm formation along with antifungal profiles inter-play a role in the pathogenicity of Malassezia spp. and might explain the implication of some Malassezia spp. in invasive fungal infections and in the development of inflammation. LAY SUMMARY: There is still little information on the virulence factors of Malassezia spp., despite their implication in severe diseases. Phospholipase, lipase, and hemolytic activities, biofilm formation and decreased antifungal susceptibility seem to contribute to their virulence in susceptible hosts.


Subject(s)
Malassezia , Tinea Versicolor , Virulence Factors , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Hemolysis , Humans , Lipase , Phospholipases , Tinea Versicolor/drug therapy , Tinea Versicolor/microbiology
19.
J Mycol Med ; 32(4): 101301, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35700659

ABSTRACT

BACKGROUND: The genus Malassezia represents the dominant eukaryotic component of the skin microbial flora. There are complex interactions between this commensal and the skin, leading to various Malassezia-caused or Malassezia exacerbated skin conditions. OBJECTIVES: To identify Malassezia species in lesions of patients with pityriasis versicolor (PV), atopic dermatitis (AD), and seborrheic dermatitis (SD), as well as corresponding sites in healthy subjects according to the culture methods used for Malassezia species isolation. METHODS: Scrapings were collected from 80 patients (40 PV, 20 AD, and 20 SD) and 30 healthy subjects. For 10-14 days, specimens were cultured on Dixon's medium and Malt extract agar. Direct microscopic examination with Gram's stain, subculture on Hi chrome agar, Dixon's medium at various temperatures, Tweens assimilation, and hydrolysis of tryptophan were used for the identification of yeast isolates. RESULTS: The isolation frequency of Malassezia species in healthy subjects was 13.3% for M. furfur, 10.0% for M. globosa, and 3.3% for M.sympodialis. In patients with SD, M. furfur was isolated more frequently from scalp lesions (25.0%) and then M. sympodialis (15%) and M. globosa (10%). Malassezia sympodialis was the most prevalent isolated species in AD lesions (20%), followed by M. furfur (10%). Malassezia species isolation was found to be most prevalent in PV lesions, with M. furfur being the most prevalent identified species (52.5 %), followed by unidentified species (20%). CONCLUSIONS: Malassezia species composition was similar in PV, SD, and healthy subjects, with M. furfur being the commonest isolate, while Malassezia sympodialis was the prevalent species isolated in AD lesions. Chrome agar media can be promising for the identification of Malassezia species phenotypically. However, species differentiation has to be complemented by molecular methods.


Subject(s)
Dermatitis, Atopic , Malassezia , Tinea Versicolor , Humans , Agar , Tinea Versicolor/epidemiology , Tinea Versicolor/diagnosis , Skin
20.
Article in English | MEDLINE | ID: mdl-35751534

ABSTRACT

Malassezia is a commensal fungus that constitutes normal skin microbiota. However, in certain conditions and individuals, it may transform into a pathogenic yeast with multiple associated dermatological disorders and various clinical manifestations. This phenomenon is influenced by a unique host-agent interaction that triggers the production of several virulence factors, such as indoles, reactive oxygen species, azelaic acid, hyphae formation, and biofilm formation. This review article discusses Malassezia virulence factors that contribute to the transformation of Malassezia from commensal to pathogenic as well as their role in dermatological disorders, including pityriasis versicolor, seborrheic dermatitis, Malassezia folliculitis, atopic dermatitis, and psoriasis.


Subject(s)
Dermatitis, Seborrheic , Dermatomycoses , Malassezia , Tinea Versicolor , Dermatitis, Seborrheic/microbiology , Dermatomycoses/microbiology , Humans , Skin , Tinea Versicolor/microbiology , Virulence Factors
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