Molecular identification and prevalence of malassezia species in pityriasis versicolor patients from kashan, iran

MalaSelect: A Selective Culture Medium for Malassezia Species

Malassezia species are fastidious and slow-growing yeasts in which isolation from polymicrobial samples is hampered by fast-growing microorganisms. Malassezia selective culture media are needed. Although cycloheximide is often used, some fungi, including the chief human commensal Candida albicans, are resistant to this compound. This study aimed to test whether the macrolide rapamycin could be used in combination with cycloheximide to develop a Malassezia-selective culture medium. Rapamycin susceptibility testing was performed via microdilution assays in modified Dixon against two M. furfur and five Candida spp. The MIC was the lowest concentration that reduced growth by a minimum of 90%. Rapamycin ± cycloheximide 500 mg/L was also added to FastFung solid, and yeast suspensions were inoculated and incubated for 72 h. Rapamycin MICs for Candida spp. ranged from 0.5 to 2 mg/L, except for C. krusei, for which the MIC was >32 mg/L. M. furfur stains were rapamycin-resistant. Rapamycin and cycloheximide supplementation of the FastFung medium effectively inhibited the growth of non-Malassezia yeast, including cycloheximide-resistant C. albicans and C. tropicalis. Based on our findings, this “MalaSelect” medium should be further evaluated on polymicrobial samples for Malassezia isolation and culture.

Molecular epidemiology, in vitro susceptibility and exoenzyme screening of Malassezia clinical isolates

Introduction. Malassezia folliculitis (MF) and pityriasis versicolor (PV) are common dermatoses caused by Malassezia species. Their molecular epidemiology, drug susceptibility and exoenzymes are rarely reported in China.Aim. To investigate the molecular epidemiology, drug susceptibility and enzymatic profile of Malassezia clinical isolates.Methodology. Malassezia strains were recovered from MF and PV patients and healthy subjects (HS) and identified by sequencing analysis. The minimum inhibitory concentrations (MICs) of nine antifungals (posaconazole, voriconazole, itraconazole, fluconazole, ketoconazole, miconazole, bifonazole, terbinafine and caspofungin) and tacrolimus, the interactions between three antifungals (itraconazole, ketoconazole and terbinafine) and tacrolimus, and the extracellular enzyme profile were evaluated using broth and checkerboard microdilution and the Api-Zym system, respectively.Results. Among 392 Malassezia isolates from 729 subjects (289 MF, 218 PV and 222 HS), Malassezia furfur and Malassezia globosa accounted for 67.86 and 18.88 %, respectively. M. furfur was the major species in MF and PV patients and HS. Among 60M. furfur and 50M. globosa strains, the MICs for itraconazole, posaconazole, voriconazole and ketoconazole were <1 μg ml^-1. M. furfur was more susceptible to itraconazole, terbinafine and bifonazole but tolerant to miconazole compared with M. globosa (P<0.05). Synergistic effects between terbinafine and itraconazole or between tacrolimus and itraconazole, ketoconazole or terbinafine occurred in 6, 7, 6 and 9 out of 37 strains, respectively. Phosphatases, lipases and proteases were mainly secreted in 51 isolates.Conclusions. Itraconazole, posaconazole, voriconazole and ketoconazole are theagents against which there is greatest susceptibility. Synergistic effects between terbinafine and itraconazole or tacrolimas and antifungals may be irrelevant to clinical application. Overproduction of lipases could enhance the skin inhabitation of M. furfur.

Phenotypic Identification and Molecular Characterization of Malassezia Spp. Isolated from Pityriasis Versicolor Patients with Special Emphasis to Risk Factors in Diyala Province, Iraq

AIM

The main objective is isolation and molecular characterisation of Malassezia spp. from pityriasis versicolor (PV) patients with special emphasis to risk factors in Diyala province, Iraq.

METHODS

Fifty patients (32 males and 18 females) presented with PV, the age ranged (15-45) years were included. Direct wet mount using KOH 10%, culture of skin scraping and PCR were used for confirmatory diagnosis.

RESULTS

Malassezia spp. was isolated from (54%) of skin scraping; M. furfur (32%); M. pachydermatis (8%) and M. globosa (14%). The age group (15-22) years were frequently exposed to Malassezia infection. A significant inverse correlation was reported between age and exposure to Malassezia spp. Infection. Males were frequently exposed to Malassezia infection, (40%). A significant correlation was reported between gender and exposure to Malassezia spp. Infection. Females were at risk of getting Malassezia infection (2.619) time than males. Patient resident in the urban area frequently exposed to Malassezia infection, (34%). Patients resident in the rural area appears to be at risk of getting Malassezia infection (1.093) time than those in an urban area. Patient with good economic status was frequently exposed to Malassezia infection, (36%). Patients with middle economic status appear to be at risk of getting Malassezia infection (0.42) time than those with good economic status. Patients with primary education were frequently exposed to Malassezia infection, (22%). A significant correlation was reported between education level and exposure to Malassezia spp. Infection. No significant correlation was reported between economic status; type of job; source of water; contact with dogs and birds and Malassezia spp. Infection.

CONCLUSION

M. furfur, M. pachydermatis and M. globosa represent the most common Malassezia spp. causing PV. Using of PCR is very critical to confirm the diagnosis of Malassezia spp. Malassezia infection inversely correlated with age and positively correlated with females gender and education. The residency in a rural area and middle economic status increase the possibility of infection. Infection was not affected by the source of water; job and contact with dogs and birds.

Distribution of Malassezia Species from Scales of Patient with Pityriasis Versicolor by Culture in Vietnam

BACKGROUND

The detection of pathogenic fungus is an important step and key to assessing the sensitivity of the antifungal drugs, and therefore choosing an effective treatment method.

AIM

To identify Malassezia species from scales of a patient with pityriasis versicolor.

METHODS

Three hundred patients with pityriasis versicolor who were positive with direct examination, were isolated by culture.

RESULTS

Identification of Malassezia species by culture: the growth rate was 90.3%; the detection rate was 97.0%, including 11 species: M. globosa (42.4%), M. dermatitis (17.3%), M. furfur (14.4%). M. globosa was the most prevalent species in the 20-29 group 36.5%, in hyphae and yeast cells (42.2%).

CONCLUSION

M. globosa is the main cause of pityriasis versicolor in Vietnam.

MALDI-TOF MS identification of Malassezia species isolated from patients with pityriasis versicolor at the seafarers' medical service in Dakar, Senegal

Pityriasis versicolor (PV) is a superficial mycosis caused by yeast of the genus Malassezia. The most common isolated Malassezia species in PV lesions differ among M. furfur, M. globosa and M. sympodialis. We purpose to determine the distribution of Malassezia species in PV patients at the seafarers' medical service in Dakar, Senegal and to examine whether any association between identified Malassezia species and patients' profile. From May 2017 to August 2017, first a questionnaire was filled to get informative data before collection of skin scrapings taken from most scaly site using sterile scalpel blade and application of scotch^® for direct examination (DE). At the laboratory, DE, culture and identification by MALDI-TOF MS were done. One hundred patients with PV - all men - were included with a mean age of 34 years. Among seafarers, 81% were sailors. Clinical prevalence of PV was highest in aged adults patients with ages of 31 to 60 years (56%). Seafarers with high level of education were less representative with only 2%. The mean duration of the PV was 26.83 months. 20% of subjects suffered lesions in more than one location. The chest was the most affected anatomical site. Furthermore, possible predisposing factors associated with PV were also detected. DE was positive in 95% but culture growth only in 46%. MALDI-TOF MS analysis of the positive cultures could be performed in 84.8% (39/46). Only M. furfur was identified in 100% (39/39). In definitive, M. furfur is the only causative agent of PV in Dakar.

Epidemiology of dermatomycoses in Kerman province, southeast of Iran: A 10-years retrospective study (2004-2014)

OBJECTIVES

Superficial and cutaneous fungal infections (SCFIs) are an important public health problem and are common in tropical and subtropical countries. Pityriasis versicolor, dermatophytosis, erythrasma, onychomycosis, and otomycosis are the major diseases associated with SCFIs. The aim of this study was to evaluate the prevalence and causative agents of dermatomycoses over a period of 10 years in Kerman province, southeast of Iran.

METHODS

A number of 1782 subjects, including 1096 females and 686 males, with cutaneous disorders in their skin, nail, and hair suspected to have SCFIs participated in this study. The collected specimens were examined using direct microscopy examination, staining, culture on specific media and PCR-RFLP technique.

RESULTS

In total, 617 (34.62%) subjects had SCFIs, of whom 290 (47%) were female and 327 (53%) were male. Identified SCFIs included yeast infections, dermatophytosis, saprophyte onychomycosis, erythrasma, and otomycosis due to non-dermatophytic molds (NDMs). The highest prevalence of dermatomycoses was found among the 41-50-year and 31-40-year age groups. Tinea unguium was the most common clinical pattern of dermatomycoses, and T. mentagrophytes was the predominant agent. Also, Aspergillus spp. were the most common NDMs agents of onychomycosis and otomycosis.

CONCLUSIONS

This study summarized the epidemiological trends and etiologic agents of SCFIs in a 10-year period in Kerman, southeast of Iran. Consideration of the current epidemiologic trends in the prevalence and knowledge of the exact causative agents of SCFIs may play an important key role towards further investigations, diagnosis, and modification of current treatments.