Malassezia Research Articles

Leaves of Vallisneria Finds Source to Anti Dermatitis: Enriching Wetland Ecosystem

The renaissances of phyto-medicines lead to a resolute search of potential medicinal plants worldwide. In this perspective, predominantly, terrestrial allelochemistry has been an imperative tool to evaluate the drug potentiality of a plant. However, in aquatic ecosphere, the pharmaceutical evaluation of the aquatic macrophytes is an emerging aspect. Our study seeks to explore the curative traits of the exotic macrophyte, Vallisneria spiralis L. (Hydrocharitaceae), a perennial stoloniferous species and a key ecological community in freshwater wetland ecosystem. It is commonly used as aquarium plant and inhabits both in lentic and lotic environment of tropical and sub-tropical regions worldwide. Being rapid colonizers of aquatic ecosystem, literature study states the leaves of the macrophyte can excrete special function groups that can absorb, filter and precipitate chemical compound of water and through the auxiliary function of the microorganism. Considering these significances, we have extracted the leaf leachates of Vallisneria in 80% ethanol which had been purified by solid-liquid extraction process and further crystallized and subjected to biochemical analysis viz; phenols, flavonoids and tannins followed by antioxidant scavenging and microbial screening. Further the isolated compound was subjected to Mass and Fourier Infra-red Spectrometry. Comprehensively, all the experimental assays infer that Vallisneria leaves contain bioactive compound with mol wt. m/z 359 structured with microbial growth inhibiting functional groups which were found fungicidal against Malassezia globosa - the dandruff causing dermatitis fungus.

English

Malassezia species are yeasts that can be present on healthy human skin but also associated with external otitis and other skin diseases. The aim of this work was the identification of Malassezia -lipophilic- species recovered from infants with otitis media. Microbiological culture, polymerase chain reaction (PCR) and sequencing were performed for Malassezia detection in samples obtained from two cases of infants with otitis media. We identified two strains of lipid-dependent Malassezia species: M. furfur and M. restricta. This is the first report regarding the presence of Malassezia species in infants with otitis media in Monterrey, Mexico. Key words: Malassezia, Malassezia furfur, Malassezia restricta, otitis media, infants, LSU rDNA D1/D2, yeasts.

English

BACKGROUND: Tinea versicolor is a chronic, mild, usually asymptomatic infection of the stratum corneum. The lesions are discrete or confluent and appear as discolored or hypo pigmented areas of the skin. The affected areas are located principally on the chest, abdomen, upper extremities and back. The etiologic agent is the lipophilic yeast Pityrosporum orbiculare, part of the normal flora of the human skin. This study is undertaken to know “clinical, patterns of the disease with respect to morphology and distribution, associated conditions and epidemiological factors like age, sex distribution and seasonal variation of the disease”. METHODS: Two hundred patients of tinea versicolor were selected. Patients belonging to the age group of above 10 years and below 60 years belonging to both sexes were selected and included in the study group after taking consent. A detailed history was taken with particular reference to onset, duration, symptoms and treatment taken and were recorded. Factors like – seasonal variation, family history and presence of any associated illnesses was also noted. A thorough clinical examination was done with reference to the location, the color, the extent of the lesions, the margins, the type of lesions and the details were recorded. Potassium hydroxide (KOH) examination and Wood’s lamp examination were done in all the patients before therapy. RESULTS: Out of 200 patients, majority of them belong to 2nd and 3rd decade of life (72%). The Male: Female ratio was 1.5:1. There was a family history of 16%. The trunk was the most common site involved. Majority of the patients had exacerbation in summer. The most common associated dermatoses were acne vulgaris, immunosuppression and infections. INTERPRETATION AND CONCLUSION: Tinea versicolor is a disease of worldwide distribution, although it is significantly more common in humid and tropical climates. The true incidence cannot be estimated precisely because the disease is not troublesome and often passes unnoticed and the patients are therefore less frequently seen by a dermatologist. The lesions are discrete or confluent and appear as discolored or hypopigmented areas of the skin Although Tinea versicolor is a chronic, mild, usually asymptomatic infection of the skin it poses considerable therapeutic challenge to dermatologists in tropical countries because of its varied clinical manifestations and frequent relapses after treatment.

Eukaryote culturomics of the gut reveals new species.

The repertoire of microeukaryotes in the human gut has been poorly explored, mainly in individuals living in northern hemisphere countries. We further explored this repertoire using PCR-sequencing and culture in seven individuals living in four tropical countries. A total of 41 microeukaryotes including 38 different fungal species and three protists were detected. Four fungal species, Davidiella tassiana, Davidiella sp., Corticiaceae sp., and Penicillium sp., were uniquely detected by culture; 27 fungal species were uniquely detected using PCR-sequencing and Candida albicans, Candida glabrata, Trichosporon asahii, Clavispora lusitaniae, Debaryomyces hansenii, Malassezia restricta, and Malassezia sp. were detected using both molecular and culture methods. Fourteen microeukaryotes were shared by the seven individuals, whereas 27 species were found in only one individual, including 11 species in Amazonia, nine species in Polynesia, five species in India, and two species in Senegal. These data support a worldwide distribution of Malassezia sp., Trichosporon sp., and Candida sp. in the gut mycobiome. Here, 13 fungal species and two protists, Stentor roeseli and Vorticella campanula, were observed for first time in the human gut. This study revealed a previously unsuspected diversity in the repertoire of human gut microeukaryotes, suggesting spots for further exploring this repertoire.

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

Background:Malassezia species are lipophilic yeasts found on the skin surface of humans and other warm-blooded vertebrates. It is associated with various human diseases, especially pityriasis versicolor, which is a chronic superficial skin disorder.Objectives:The aim of the present study was to identify Malassezia species isolated from patients’ samples affected by pityriasis versicolor, using molecular methods in Kashan, Iran.Patients and Methods:A total of 140 subjects, suspected of having pityriasis versicolor from Kashan, were clinically diagnosed and then confirmed by direct microscopic examination. The scraped skin specimens were inoculated in modified Dixon’s medium. DNA was extracted from the colonies and PCR amplification was carried out for the 26s rDNA region. PCR products were used to further restriction fragment length polymorphism by CfoI enzyme.Results:Direct examination was positive in 93.3% of suspected pityriasis versicolor lesions. No statistically significant difference was observed in the frequency of Malassezia species between women and men. The highest prevalence of tinea versicolor was seen in patients 21–30 years-of-age. No difference could be seen in the frequency of Malassezia species depending on the age of the patients. In total, 65% of patients with pityriasis versicolor had hyperhidrosis. The most commonly isolated Malassezia species in the pityriasis versicolor lesions were; Malassezia globosa (66%), M. furfur (26%), M. restricta (3%), M. sympodialis (3%), and M. slooffiae (2%). Malassezia species were mainly isolated from the neck and chest.Conclusions:This study showed M. globosa to be the most common Malassezia species isolated from Malassezia skin disorders in Kashan, Iran. The PCR-RFLP method was useful in the rapid identification of the Malassezia species. By using these methods, the detection and identification of individual Malassezia species from clinical samples was substantially easier.

Biochemical properties of a new cold-active mono- and diacylglycerol lipase from marine member Janibacter sp. strain HTCC2649.

Mono- and di-acylglycerol lipase has been applied to industrial usage in oil modification for its special substrate selectivity. Until now, the reported mono- and di-acylglycerol lipases from microorganism are limited, and there is no report on the mono- and di-acylglycerol lipase from bacteria. A predicted lipase (named MAJ1) from marine Janibacter sp. strain HTCC2649 was purified and biochemical characterized. MAJ1 was clustered in the family I.7 of esterase/lipase. The optimum activity of the purified MAJ1 occurred at pH 7.0 and 30 °C. The enzyme retained 50% of the optimum activity at 5 °C, indicating that MAJ1 is a cold-active lipase. The enzyme activity was stable in the presence of various metal ions, and inhibited in EDTA. MAJ1 was resistant to detergents. MAJ1 preferentially hydrolyzed mono- and di-acylglycerols, but did not show activity to triacylglycerols of camellia oil substrates. Further, MAJ1 is low homologous to that of the reported fungal diacylglycerol lipases, including Malassezia globosa lipase 1 (SMG1), Penicillium camembertii lipase U-150 (PCL), and Aspergillus oryzae lipase (AOL). Thus, we identified a novel cold-active bacterial lipase with a sn-1/3 preference towards mono- and di-acylglycerides for the first time. Moreover, it has the potential, in oil modification, for special substrate selectivity.

Antimicrobial Activity of Ethanol Extract ofSenna Alata Leaves against Some Selected Microorganism in Bayelsa State, Nigeria

Senna alata is an underutilized shrub growing in many parts of the world and is known for its traditional use in the treatment of dermotophytes and other related ailment. The ethanol extract of Senna alata leaves was evaluated against some dermotophytes ( Malassezia pachydermatis, Malassezia furfure, and Malassezia restricta, Malassezia globosa) and gastrointestinal bacterial pathogens ( Salmonella Typhi, Escherichia coli , Proteus mirabilis , Pseudomonas auriginosa , Klebsiella spp). The extract was tested using well diffusion technique against pathogens and found effective against the selected pathogens. The highest zone of inhibition was observed against Klebsiella spp (27.4mm), followed by S. Typhi (26mm) and P. auriginosa (26mm), P. mirabilis (21.7mm) and E. coli (19.5mm). In case of fungi, it was most effective against M. globosa (19.7mm) and M. pachydermatis (17mm). It was not effective against M. furfure and M. restricta . Thus, S. alata is a good antimicrobial agent against bacterial and fungal pathogens of humans.

Genotype analyses of human commensal scalp fungi, Malassezia globosa, and Malassezia restricta on the scalps of patients with dandruff and healthy subjects.

Dandruff and seborrheic dermatitis are common afflictions of the human scalp caused by commensal scalp fungi belonging to the genus Malassezia. Malassezia globosa and Malassezia restricta are the predominant species found on the scalp. The intergenic spacer regions of these species' rRNA genes contain short sequence repeats (SSR): (GT)n and (CT)n in M. globosa and (CT)n and (AT)n in M. restricta. In the present study, we compared the genotypes (SSR) of M. globosa and M. restricta colonizing the scalps of patients with dandruff and healthy individuals. For M. globosa, the genotype (GT)10:(CT)8 (40.3%, 25/62) was predominant followed by (GT)9:(CT)8 (14.5%, 9/62) and (GT)11:(CT)8 (14.5%, 9/62) in patients with dandruff, whereas the genotypes in healthy subjects were diverse. For M. restricta, the genotype (CT)6:(AT)6 (59.7%, 37/62) was predominant followed by (CT)6:(AT)8 (24.2%, 15/62) in patients with dandruff, while four genotypes, (CT)6:(AT)6 (10.5%, 6/57), (CT)6:(AT)7 (22.8%, 13/57), (CT)6:(AT)8 (17.5%, 10/57), and (CT)6:(AT)10 (21.1%, 12/57), accounted for 71.9% of all combinations in healthy subjects. The results of this study suggest that the M. globosa genotype (GT)10:(CT)8 and the M. restricta genotype (CT)6:(AT)6 may be involved in the development of dandruff.

Chemical Organization of the Cell Wall Polysaccharide Core of Malassezia restricta

Malassezia species are ubiquitous residents of human skin and are associated with several diseases such as seborrheic dermatitis, tinea versicolor, folliculitis, atopic dermatitis, and scalp conditions such as dandruff. Host-Malassezia interactions and mechanisms to evade local immune responses remain largely unknown. Malassezia restricta is one of the most predominant yeasts of the healthy human skin, its cell wall has been investigated in this paper. Polysaccharides in the M. restricta cell wall are almost exclusively alkali-insoluble, showing that they play an essential role in the organization and rigidity of the M. restricta cell wall. Fractionation of cell wall polymers and carbohydrate analyses showed that the polysaccharide core of the cell wall of M. restricta contained an average of 5% chitin, 20% chitosan, 5% β-(1,3)-glucan, and 70% β-(1,6)-glucan. In contrast to other yeasts, chitin and chitosan are relatively abundant, and β-(1,3)-glucans constitute a minor cell wall component. The most abundant polymer is β-(1,6)-glucans, which are large molecules composed of a linear β-(1,6)-glucan chains with β-(1,3)-glucosyl side chain with an average of 1 branch point every 3.8 glucose unit. Both β-glucans are cross-linked, forming a huge alkali-insoluble complex with chitin and chitosan polymers. Data presented here show that M. restricta has a polysaccharide organization very different of all fungal species analyzed to date.

Distribution of Malassezia species in patients with pityriasis versicolor in Turkey

Pityriasis versicolor is a common superficial mycotic disease of the skin which is caused by different species of Malassezia genus. The aim of this study was to contribute to the knowledge of the aetiology of pityriasis versicolor (PV) with a mycological study made according to the new species and additionally, the success of the different sampling techniques, duration and recurrence history of the disease, distribution of infecting strains according to the affected body sites were also investigated. In total, 146patients with pityriasis versicolor were included in this study. Fungal elements could only be visualized by potassium hydroxide examination in 36.4% of the samples. Specimens obtained by scraping skin surface by a sterile scalpel and/or sterile sticky plaster (OpSite) were inoculated in plates containing modified Dixon's medium. Out of 146samples, 109 (74.7%) yielded a growth which was considered to be Malassezia spp. in culture. Species level identification of suspicious Malassezia yeasts was made according to their macroscopic and microscopic features, and their physiological characteristics. Among the identified species, Malassezia globosa (65.1%) was the most commonly isolated species, followed by Malassezia obtusa (17.4%). However, four Malassezia isolates could not be identified at species level with conventional methods. While most of the patients suffered their first episode of pityriasis versicolor (76%), back of the trunk was the mostly affected body site (39%). In conclusion, Malassezia globosa was found to be the predominant species in pityriasis versicolor patients in our region, and culture of the specimen is necessary for the epidemiologic purposes.

ESCMID and ECMM joint clinical guidelines for the diagnosis and management of rare invasive yeast infections

The mortality associated with invasive fungal infections remains high with that involving rare yeast pathogens other than Candida being no exception. This is in part due to the severe underlying conditions typically predisposing patients to these healthcare-related infections (most often severe neutropenia in patients with haematological malignancies), and in part due to the often challenging intrinsic susceptibility pattern of the pathogens that potentially leads to delayed appropriate antifungal treatment. A panel of experts of the European Society of Clinical Microbiology and Infectious Diseases (ESCMID) Fungal Infection Study Group (EFISG) and the European Confederation of Medical Mycology (ECMM) undertook a data review and compiled guidelines for the diagnostic tests and procedures for detection and management of rare invasive yeast infections. The rare yeast pathogens were defined and limited to the following genera/species: Cryptococcus adeliensis, Cryptococcus albidus, Cryptococcus curvatus, Cryptococcus flavescens, Cryptococcus laurentii and Cryptococcus uniguttulatus (often published under the name Filobasidium uniguttulatum), Malassezia furfur, Malassezia globosa, Malassezia pachydermatis and Malassezia restricta, Pseudozyma spp., Rhodotorula glutinis, Rhodotorula minuta and Rhodotorula mucilaginosa, Sporobolomyces spp., Trichosporon asahii, Trichosporon asteroides, Trichosporon dermatis, Trichosporon inkin, Trichosporon jirovecii, Trichosporon loubieri, Trichosporon mucoides and Trichosporon mycotoxinivorans and ascomycetous ones: Geotrichum candidum, Kodamaea ohmeri, Saccharomyces cerevisiae (incl. S. boulardii) and Saprochaete capitatae (Magnusiomyces (Blastoschizomyces) capitatus formerly named Trichosporon capitatum or Geotrichum (Dipodascus) capitatum) and Saprochaete clavata. Recommendations about the microbiological investigation and detection of invasive infection were made and current knowledge on the most appropriate antifungal and supportive treatment was reviewed. In addition, remarks about antifungal susceptibility testing were made.

Site-directed mutagenesis studies of the aromatic residues at the active site of a lipase from Malassezia globosa

The lipase from Malassezia globosa (SMG1) has specific activity on mono- and diacylglycerol but not on triacylglycerol. The structural analysis of SMG1 structure shows that two bulky aromatic residues, W116 and W229, lie at the entrance of the active site. To study the functions of these two residues in the substrate recognition and the catalytic reaction, they were mutated to a series of amino acids. Subsequently, biochemical properties of these mutants were investigated. Although the activities decrease, W229L and W116A show a significant shift in substrate preference. W229L has an increased preference for short-chain substrates whereas W116A has preference for long-chain substrates. Besides, the half-lives of W116A and W116H at 45 °C are 346.6 min and 115.5 min respectively, which improve significantly compared to that of native enzyme. Moreover, the optimum substrate of W116A, W116F and W229F mutants shifted from p-nitrophenyl caprylate to p-nitrophenyl myristate. These findings not only shed light onto the lipase structure/function relationship but also lay the framework for the potential industrial applications.

Mycology – an update. Part 1: Dermatomycoses: Causative agents, epidemiology and pathogenesis

Dermatomycoses are caused most commonly by dermatophytes. The anthropophilic dermatophyte Trichophyton rubrum is still the most frequent causative agent worldwide. Keratinolytic enzymes, e.g. hydrolases and keratinases, are important virulence factors of T.rubrum. Recently, the cysteine dioxygenase was found as new virulence factor. Predisposing host factors play a similarly important role for the development of dermatophytosis of the skin and nails. Chronic venous insufficiency, diabetes mellitus, disorders of cellular immunity, and genetic predisposition should be considered as risk factors for onychomycosis. A new alarming trend is the increasing number of cases of onychomycosis - mostly due to T.rubrum - in infancy. In Germany, tinea capitis is mostly caused by zoophilic dermatophytes, in particular Microsporum canis. New zoophilic fungi, primarily Trichophyton species of Arthroderma benhamiae, should be taken into differential diagnostic considerations of tinea capitis, tinea faciei, and tinea corporis. Source of infection are small household pets, particularly rodents, like guinea pigs. Anthropophilic dermatophytes may be introduced by families which immigrate from Africa or Asia to Europe. The anthropophilic dermatophytes T.violaceum, T.tonsurans (infections occurring in fighting sports clubs as "tinea gladiatorum capitis et corporis") and M.audouinii are causing outbreaks of small epidemics of tinea corporis and tinea capitis in kindergartens and schools. Superficial infections of the skin and mucous membranes due to yeasts are caused by Candida species. Also common are infections due to the lipophilic yeast fungus Malassezia. Today, within the genus Malassezia more than 10 different species are known. Malassezia globosa seems to play the crucial role in pityriasis versicolor. Molds (also designated non-dermatophyte molds, NDM) are increasingly found as causative agents in onychomycosis. Besides Scopulariopsis brevicaulis, several species of Fusarium and Aspergillus are found.

A new approach to the diagnosis and study of M alassezia infections

A new approach to the diagnosis and study of <i> <scp>M</scp> alassezia </i> infections

Antimycotics suppress the Malassezia extract‐induced production of CXC chemokine ligand 10 in human keratinocytes

Malassezia, a lipophilic yeast, exacerbates atopic dermatitis. Malassezia products can penetrate the disintegrated stratum corneum and encounter subcorneal keratinocytes in the skin of atopic dermatitis patients. Type 1 helper T (Th1) cells infiltrate chronic lesions with atopic dermatitis, and antimycotic agents improve its symptoms. We aimed to identify Malassezia-induced chemokines in keratinocytes and examine whether antimycotics suppressed this induction. Normal human keratinocytes were incubated with a Malassezia restricta extract and antimycotics. Chemokine expression was analyzed by enzyme-linked immunosorbent assays and real-time polymerase chain reaction. Signal transducer and activator of transcription (STAT)1 activity was examined by luciferase assays. The tyrosine-phosphorylation of STAT1 was analyzed by western blotting. The M.restricta extract increased the mRNA and protein expression of Th1-attracting CXC chemokine ligand (CXCL)10 and STAT1 activity and phosphorylation in keratinocytes, which was suppressed by a Janus kinase inhibitor. The antimycotics itraconazole, ketoconazole, luliconazole, terbinafine, butenafine and amorolfine suppressed M.restricta extract-induced CXCL10 mRNA and protein expression and STAT1 activity and phosphorylation. These effects were similarly induced by 15-deoxy-Δ-(12,14) -prostaglandin J2 (15d-PGJ2 ), a prostaglandin D2 metabolite. Antimycotics increased the release of 15d-PGJ2 from keratinocytes. The antimycotic-induced suppression of CXCL10 production and STAT1 activity was counteracted by a lipocalin-type prostaglandin D synthase inhibitor. The antimycotics itraconazole, ketoconazole, luliconazole, terbinafine, butenafine and amorolfine may suppress the M.restricta-induced production of CXCL10 by inhibiting STAT1 through an increase in 15d-PGJ2 production in keratinocytes. These antimycotics may block the Th1-mediated inflammation triggered by Malassezia in the chronic phase of atopic dermatitis.

Do Malassezia species play a role in exacerbation of scalp psoriasis?

Clinical expression of psoriasis is in part dependent on external factors, such as drugs, microorganisms or stress. However convincing evidence of the role of Malassezia species in the pathogenesis of the psoriasis is still lacking. Samples taken from scalp skin of 40 psoriatic patients and the same number of healthy individuals were observed under direct microsocopic examination and cultured on modified Dixon agar. Direct microscopy examination of psoriatic scalp scales was positive in 30 (75%) patients; while it was positive in only 12 (30%) healthy subjects (P=0.003). Half of the cultures from healthy subjects showed no growth of colonies, but only 8 (15%) of psoriatic patients were negative. When an exacerbation has occurred in the previous weeks, pseudohyphaes were observed in 12 (40%) patients, Malassezia globosa was isolated in 18 (45%) patients and Malassezia restricta was isolated in 12 (30%) patients. In the group of patients having stable lesion, without any exacerbation in the previous weeks, no pseudohypahes were observed, M.globosa was not isolated, M.restricta was isolated in 4 (10%), and cultures were negative in 6 of them (15%). Malassezia species form an integral part of normal cutaneous microflora in humans, however we found that during the episodes of exacerbation of the disease the presence of these yeasts, and particularly M.globosa, was increased.

Utilization of matrix‐assisted laser desorption and ionization time‐of‐flight mass spectrometry for identification of infantile seborrheic dermatitis‐causing Malassezia and incidence of culture‐based cutaneous Malassezia microbiota of 1‐month‐old infants

Matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF-MS) has been utilized for identification of various microorganisms. Malassezia species, including Malassezia restricta, which is associated with seborrheic dermatitis, has been difficult to identify by traditional means. This study was performed to develop a system for identification of Malassezia species with MALDI-TOF-MS and to investigate the incidence and variety of cutaneous Malassezia microbiota of 1-month-old infants using this technique. A Malassezia species-specific MALDI-TOF-MS database was developed from eight standard strains, and the availability of this system was assessed using 54 clinical strains isolated from the skin of 1-month-old infants. Clinical isolates were cultured initially on CHROMagar Malassezia growth medium, and the 28S ribosomal DNA (D1/D2) sequence was analyzed for confirmatory identification. Using this database, we detected and analyzed Malassezia species in 68% and 44% of infants with and without infantile seborrheic dermatitis, respectively. The results of MALDI-TOF-MS analysis were consistent with those of rDNA sequencing identification (100% accuracy rate). To our knowledge, this is the first report of a MALDI-TOF-MS database for major skin pathogenic Malassezia species. This system is an easy, rapid and reliable method for identification of Malassezia.

Elevated Serum IgE against MGL_1304 in Patients with Atopic Dermatitis and Cholinergic Urticaria

MGL_1304 secreted by Malassezia globosa is contained in human sweat and induces histamine release from basophils in patients with atopic dermatitis (AD) at a high positive rate. The aims of this study were to establish the enzyme-linked immunosorbent assay (ELISA) measuring specific immunoglobulins against MGL_1304 and to investigate the levels of these immunoglobulins in sera of patients with various allergic diseases. Purified MGL_1304 from human sweat (QRX) and recombinant MGL_1304 (rMGL_1304) were prepared for ELISA. To quantify the amount of MGL_1304-specific immunoglobulins, the standard serum was created by pooling sera of 20 patients with AD whose basophils released histamine in response to QRX. A monoclonal antibody which exhibited the highest neutralizing ability against QRX was established as Smith-2, and used as a capture antibody for the assay of QRX-specific IgE. A total of 156 subjects [normal controls (n = 23), AD (n = 63), cholinergic urticaria (CU) (n = 24), bronchial asthma (n = 32), and allergic rhinitis (n = 14)] were enrolled in this study. ELISA methods to quantify the specific IgE, IgG and IgG4 against MGL_1304 in sera were successfully established. Levels of QRX-specific IgE in sera of patients with AD and CU were significantly higher than those of normal controls. Moreover, the levels of QRX-specific IgE and rMGL_1304-specific IgE in patients with AD were significantly correlated with their disease severities. These ELISA methods to quantify the specific immunoglobulins against MGL_1304 are easy and useful means to assess allergy to MGL_1304. MGL_1304 contained in sweat is an important antigen for patients with AD and CU.

Relationships among the Genotypes of Malassezia Globosa Colonizing Patients with Atopic Dermatitis, the Clinical Severity of the Disease, and the Level of Specific IgE Antibodies

Background: Various types of microorganisms colonize the skin surface, and some such as the bacterium Staphylococcus aureus and fungus Malassezia, exacerbate the symptoms of atopic dermatitis. Malassezia-specific IgE antibodies are present in the sera of patients with atopic dermatitis and the level thereof correlates with the severity of the condition. Malassezia has many genotypes. In the present study, we explored the relationships among the genotypes of Malassezia species colonizing patients with atopic dermatitis, the clinical severity of the disease, and the level of specific IgE antibody. Methods: Scale samples were obtained from head or neck lesions of 74 patients with atopic dermatitis and 40 healthy subjects. The intergenic spacer (IGS) 1 region of the rRNA genes of M. globosa (the major flora of patients with atopic dermatitis) were amplified by PCR and directly sequenced. M. globosa-specific IgE antibody levels were determined using the AlaSTAT™ microplate system. Results: Eighteen M. globosa IGS1 genotypes were detected in scale samples from patients with atopic dermatitis and healthy individuals. Of these, the proportion of the (GT)10:(CT)8 genotype increased with the clinical severity of disease and increasing levels of M. globosa-specific IgE antibodies, whereas this genotype was not found on the skin of healthy subjects. Conclusion: A specific genotype of Malassezia selectively colonized the skin of patients with atopic dermatitis, contributing to the clinical severity of disease. Thus, a “bad Malassezia” may be present on the skin of patients with atopic dermatitis.

Tacrolimus ointment for children's atopic dermatitis and its influence on malassezia's colonization

Objectives To evaluate the influence of tacrolimus ointment on malassezia's colonization in the lesional areas of the children with atopic dermatitis (AD).Methods The children with AD were randomly divided into a treatment group and a control group.Both groups orally administered loratadine tablets.In addition,the treatment group were treated with 0.03％ tacrolimus ointment and the control group was given Vitamin E cream twice a day for 3 weeks.The SCORAD integral drop index was used to evaluate the efficacy.Values of SCORAD and malassezia colonization density were compared before,day 7,14,and 21 of,and 14 and 28 days after the treatment.Pearson correlation analysis was used to assess the dependability between malassezia colonization density and the severity of disease.Results The SCORAD value of the treatment group markedly decreased after the treatment.The efficacy rate was 95.65 ％ in treatment group and 66.67 ％ in the control group (P ＜ 0.05).28 days after the treatment,one case recurred and the efficacy rate was 91.30％ in the treatment group and 3 cases recurred and the efficacy rate was 50.00％ in the control group,with significant differences (P ＜ 0.05).There was no significant correlation between malassezia colonization density and SCORAD integral before and after the treatment.Day 7,14,and 21 of the treatment,Malassezia colonization densities were lower in the treatment group than in the control group(P ＜ 0.05).Conclusions 0.03％ tacrolimus ointment for children with AD is effective and safe,has a low recurrence rate,and can reduce the malassezia colonization density on the surface of lesional area. Key words: Atopic dermatitis; Tacrolimus; Malassezia; Colonization