Yeasts of the genus Malassezia are part of the normal flora of human skin. However, they are also associated with various skin diseases. Since the introduction of Malassezia to the Korean Dermatologic Society two decades ago, remarkable progress has been made in our knowledge of this genus. In this paper, we review recent developments in Malassezia research, including taxonomy and methods for species identification, recent genome analyses, Malassezia species distribution in healthy conditions and in specific skin diseases, trials investigating the mechanisms underlying Malassezia-related diseases, as well as therapeutic options. This review will enhance our understanding of Malassezia yeasts and related skin diseases in Korea.
Classification ; Dermatitis, Atopic ; Dermatitis, Seborrheic ; Genome ; Humans ; Korea* ; Malassezia* ; Skin ; Skin Diseases ; Tinea Versicolor ; Yeasts

Atopic dermatitis (AD), with the prevalence rate of around 10 to 15%, is characterized by an intensely pruritic skin lesions with typical distribution and morphology. Recently, AD is divided into extrinsic type (ADe) and intrinsic type (ADi) according to the laboratory findings and associated diseases. ADe is well-known for high IgE level, positive response to food- or aero-allergens, whereas ADi has clinically similar skin lesions and distribution patterns of AD with normal serum IgE levels, negative in vitro test for environmental or food allergens and without associated atopic diseases. To instrumentally evaluate the differences of skin involvement and functions between ADi and ADe, we checked the transepidermal water loss (TEWL), capacitance and pH in both types of childhood AD and age-matched control. The proportion of ADi was around 20% in all AD patients (10/51). Our experiment suggested possible differences between ADi and ADe. Antecubital fossa is a famous involvement site of childhood type of AD, where both types of AD patients showed higher TEWL and decreased capacitance. ADe patients showed increased TEWL in all sites and lower hydration in 4 sites, whereas ADi patients showed no significant differences of TEWL and hydration in forehead, cheek, and back of leg.
Adolescent ; Case-Control Studies ; Child ; Comparative Study ; Dermatitis, Allergic Contact/immunology ; Dermatitis, Allergic Contact/physiopathology ; Dermatitis, Atopic/classification ; Dermatitis, Atopic/immunology ; Dermatitis, Atopic/physiopathology* ; Electric Capacitance* ; Female ; Human ; Hydrogen-Ion Concentration* ; Immunoglobulin E/immunology ; Male ; Skin/physiopathology* ; Water Loss, Insensible*

Allergic diseases, including allergic rhinitis, asthma, and atopic dermatitis, are common heterogeneous diseases that encompass diverse phenotypes and different pathogeneses. Phenotype studies of allergic diseases can facilitate the identification of risk factors and their underlying pathophysiology, resulting in the application of more effective treatment, selection of better treatment responses, and prediction of prognosis for each phenotype. In the early phase of phenotype studies in allergic diseases, artificial classifications were usually performed based on clinical features, such as triggering factors or the presence of atopy, which can result in the biased classification of phenotypes and limit the characterization of heterogeneous allergic diseases. Subsequent phenotype studies have suggested more diverse phenotypes for each allergic disease using relatively unbiased statistical methods, such as cluster analysis or latent class analysis. The classifications of phenotypes in allergic diseases may overlap or be unstable over time due to their complex interactions with genetic and encountered environmental factors during the illness, which may affect the disease course and pathophysiology. In this review, diverse phenotype classifications of allergic diseases, including atopic dermatitis, asthma, and wheezing in children, allergic rhinitis, and atopy, are described. The review also discusses the applications of the results obtained from phenotype studies performed in other countries to Korean children. Consideration of changes in the characteristics of each phenotype over time in an individual’s lifespan is needed in future studies.
Asthma ; Bias (Epidemiology) ; Child ; Classification ; Dermatitis, Atopic ; Humans ; Phenotype ; Prognosis ; Respiratory Sounds ; Rhinitis, Allergic ; Risk Factors

Atopic dermatitis (AD) is the most common chronic inflammatory skin disorder in children, with a worldwide cumulative prevalence in children of 8-20%. The number of AD patients is beyond the level that can be dealt with at clinics and it is time to make an effort to reduce the number of AD patients in the community. Thus, caregivers and all persons involved with AD management, including health care providers, educators, technologists and medical policy makers, should understand the development and the management of AD. Although a number of guidelines such as Practical Allergy (PRACTALL) report have been developed and used, community understanding of these is low. This is probably because there are still remarkable differences in management practices between specialists and between countries and most of the reported guidelines have been prepared for physicians. From the viewpoint of providing a basis for a multidisciplinary team approach, easily comprehensible guidelines for organizing treatment of AD, i.e. an Atopic Dermatitis Organizer (ADO), are required. guidelines should be simple and well organized. We suggest an easy approach with a new classification of AD symptoms into early and/or progressive lesions in acute and/or chronic symptoms. The contents of this ADO guideline basically consist of 3 steps approaches: conservative management, topical anti-inflammatory therapy, and systemic anti-inflammatory therapy.
Administrative Personnel ; Caregivers ; Child ; Classification ; Dermatitis, Atopic ; Health Personnel ; Humans ; Hypersensitivity ; Prevalence ; Skin ; Specialization

BACKGROUND: Systemic immunomodulatory treatment is actively recommended in the treatment for moderate to severe atopic dermatitis (AD) patients. However, consensus criteria for the classification of AD severity or treatment refractoriness have not been established yet. OBJECTIVE: To establish consensus criteria on the definition of severity classification and treatment refractoriness of AD to provide a basis for proper treatment strategy. METHODS: The Korean Atopic Dermatitis Association (KADA) comprised a task force team to establish a definition of moderate to severe AD. A draft of definition of moderate to severe AD was made on the basis of evidence. The recommendation was confirmed by KADA members through a web-based survey. RESULTS: KADA approved that AD with 16≤eczema area and severity index (EASI)<23 should be basically defined as moderate AD whereas AD with EASI score ≥23 should be considered as severe AD. They agreed that it would be reasonable to raise the severity level if patient's daytime or nighttime pruritus numerical rating scale is equal to or higher than 7 (≥7) or dermatology life quality index score exceeds 10. AD patients who do not reach EASI 50 after appropriate treatment for three months should be considered as a non-responder. Patients with recurrence (EASI ≥16) within three months after cessation of treatment should be considered as a recurrent AD. CONCLUSION: KADA built a consensus of definition of moderate and severe AD and treatment-refractoriness. These guidelines are expected to help physicians determine proper treatment options in need.
Advisory Committees ; Classification ; Consensus ; Dermatitis, Atopic ; Dermatology ; Diagnosis ; Humans ; Pruritus ; Quality of Life ; Recurrence ; Treatment Failure ; Withholding Treatment

PURPOSE: Atopic Dermatitis (AD) is a chronically relapsing inflammatory skin disease. Generally, aeroallergens and food allergens can exacerbate symptoms in AD. Currently they are divided into two groups: one is an IgE mediated form and the other is a non-IgE mediated form. This study focused upon clinical manifestations of two distinct forms of AD. METHODS: We evaluated 110 patients (male: 58, female: 52) with AD. All patients had visited Masan Samsung Hospital from June 2002 to February 2005. The patients were divided into 2 sub-groups according to their serum total IgE and specific IgE levels. The serum total IgE and specific IgE to Dermatophagoides pteronyssinus, Dermatophagoides farinae, Egg white, Cow's milk and Soybean were measured by the Pharmacia CAP-FEIA system. Metacholine provocation tests were conducted to reveal bronchial hyper-responsiveness and ARIA guidelines for diagnosis of AR were applied. RESULTS: Our study showed more female predominance in non IgE-mediated atopic dermatitis patients and showed higher total eosinophil count in IgE-mediated atopic dermatitis. (P< 0.05) There was no difference in frequency of asthma between two groups (P> 0.05), but allergic rhinitis was significantly predominant in non IgE-mediated atopic dermatitis patients. (P< 0.05) CONCLUSION: Female was more predominant in non IgE-mediated atopic dermatitis patients and IgE-mediated atopic dermatitis patients showed higher total eosinophil count and more frequency of allergic rhinitis.
Allergens ; Asthma ; Child* ; Classification* ; Dermatitis, Atopic* ; Dermatophagoides farinae ; Dermatophagoides pteronyssinus ; Diagnosis ; Egg White ; Eosinophils ; Female ; Humans ; Hypersensitivity, Immediate ; Immunoglobulin E* ; Milk ; Rhinitis ; Skin Diseases ; Soybeans

BACKGROUND: Staphylococcal scalded skin syndrome (SSSS) is defined as a spectrum of superficial blistering skin disease caused by the exfoliative toxins of Staphylococcus (S.) aureus. The spectrum of the disease includes generalized, localized (bullous impetigo), abortive and intermediate forms. OBJECTIVE: The purpose of this study is to reclassify clinical types of SSSS by reviewing the clinical and microbiologic features of SSSS and to redefine the clinical types exactly. METHODS: We retrospectively reviewed medical records, clinical photographs and the microbiologic results of 25 patients with SSSS and studied them according to the new classification. We defined the 3 clinical types as follows: i) The Generalized type is defined as a case where tender erythroderma and large thin bullae occur on the whole body excluding the mucous membrane, palms and soles. The nikolsky sign is positive. ii) The intermediate type is defined as a case where tender erythroderma and vesicles or pustules occur in the regionally limited area. The Nikolsky sign is positive. iii) The abortive type is defined as a case where tender erythema occurs only on the whole body or in regionally limited areas. The nikolsky sign is negative. All patients of SSSS have periorificial, radial crusting and fissuring. RESULTS: We could reclassify the clinical types of SSSS into 3 types (generalized, intermediate, abortive) according to this retrospective clinical study. Of the 25 patients, 3 patients were of the generalized type, 13 patients were of the intermediate type and 9 patients were of the abortive type. All the types have the acute eczematous lesion on the periorbital and perioral areas. The male to female sex ratio was 1: 1.3. The mean age of onset was 2.9 years. Cultures from the suspected site of the primary infection were positive in 14 out of 21 patients, and colonized sites were the throat (29%), conjunctiva (21%), nasal cavity (21%), ear (21%) and skin (8%) in 14 patients. Methicillin-sensitive S. aureus and methicillin-resistant S. aureus were 8 cases and 6 cases, respectively. In all clinical types, the most common complication was conjunctivitis (54.5%). Four cases were accompanied by atopic dermatitis. All the patients were cured with first generation cephalosporin without significant sequelae. CONCLUSION: We reclassified SSSS into generalized, intermediate and abortive types with reference to our 25 cases and previously existing papers, and offered a correct definition for the 3 types.
Age of Onset ; Blister ; Classification ; Colon ; Conjunctiva ; Conjunctivitis ; Dermatitis, Atopic ; Dermatitis, Exfoliative ; Ear ; Erythema ; Exfoliatins ; Female ; Humans ; Male ; Medical Records ; Methicillin Resistance ; Mucous Membrane ; Nasal Cavity ; Pharynx ; Retrospective Studies ; Sex Ratio ; Skin ; Skin Diseases ; Staphylococcal Scalded Skin Syndrome* ; Staphylococcus

BACKGROUND: Malassezia yeast are lipophilic fungi that are found in 75~80% of healthy adults. The yeast are known to be associated with pityriasis versicolor, seborrheic dermatitis, Malassezia folliculitis, and recently its pathogenicity is being expanded to other various skin disorders, such as atopic dermatitis and acne vulgaris. Up to present, mycological studies on Malassezia yeast have been carried out mostly through morphological analysis and biochemical analysis. Recently however, various molecular biological techniques are being preferred over morphological analysis, which is not a suitable method for establishing taxonomic relationship between species, and more or less time-consuming. OBJECTIVE: We sought to implement novel molecular biology technique, namely 26S rDNA PCRRFLP method in identifying and classifying Malassezia yeast, and assess its clinical applicability. METHODS: Eleven standard strains and eight clinical isolates were thoroughly examined with special attention to the shape of the colonies, size and change in media. Subsequently, the colonies were classified according to Gueho classification. For molecular analysis, RFLP analysis was carried out after DNA was isolated from each organism and 26S rDNA was amplified through PCR. The results of identification were confirmed by 26S rDNA sequencing. RESULTS: In PCR analysis to amplify the 26S rDNA, a 580bp PCR band was seen in all of eleven standard colonies. On analysis of PCR-RFLP of 26S rDNA using restriction enzymes Hha1 and BstF51, all of the database in the restriction pattern of each species was attained. On analyzing eight clinical isolates, a restriction pattern which was interspecifically distinguishable, was identified, and the result was in accord with the pattern obtained from 26S rDNA PCR-RFLP of standard colonies. Out of eight, seven clinical isolates colonies was in accord with the result of 26S rDNA PCR-RFLP. In order to assess the precision of 26S rDNA PCR-RFLP, 26S rDNA sequencing was performed, whose result was in accord with 26S rDNA PCR-RFLP analysis. CONCLUSION: As evidenced above, 26S rDNA PCR-RFLP analysis could provide a sensitive and rapid identification system for Malassezia species, which may be applied to epidemiological surveys and clinical practice
Acne Vulgaris ; Adult ; Classification* ; Dermatitis, Atopic ; Dermatitis, Seborrheic ; DNA ; DNA, Ribosomal* ; Folliculitis ; Fungi ; Humans ; Malassezia* ; Molecular Biology ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Skin ; Tinea Versicolor ; Virulence ; Yeasts*

Intradermal tests were performed on 58 dogs diagnosed with atopic dermatitis from 2004~2008 at the Veterinary Medical Teaching Hospital of Konkuk University, Korea. To compare the allergen distribution observed in the present investigation to the results from other studies conducted in Korea and elsewhere, the allergens were grouped according to their kinds. There was no significant difference in gender distribution among the dogs. The most common breeds among the 58 dogs were Maltese (n = 11) and Shih-tzu (n = 11). The average age was 4.8 years. The most frequently produced a positive reaction on the intradermal tests was mold (67.3%) followed by house dust (54.5%) and house dust mites (49.1%). The present study found a low distribution of dogs allergic to various outdoor allergens compared to studies performed in other countries; this may reflect differences in living conditions for dogs living in Korea.
Allergens/classification/*immunology ; Animals ; Dermatitis, Atopic/epidemiology/immunology/*veterinary ; Dog Diseases/epidemiology/*immunology ; Dogs ; Dust/*immunology ; Female ; Fungi/*immunology ; Intradermal Tests/veterinary ; Male ; Pedigree ; Prevalence ; Pyroglyphidae/*immunology ; Republic of Korea/epidemiology

Effective management of atopic dermatitis (AD) involves the treatment of a defective skin barrier. Patients with AD are therefore advised to use moisturizers regularly. To date, there are few comparative studies involving moisturizers in patients with AD, and no classification system exists to objectively determine which types of moisturizers are best suited to specific AD phenotypes. With this in mind, a group of experts from allergy and immunology, adult and pediatric dermatology, and pediatrics centers within Southeast Asia met to review current data and practice, and to develop recommendations regarding the use of moisturizers in patients with AD within the Asia-Pacific region. Chronicity and severity of AD, along with patient age, treatment compliance, and economic background should all be taken into account when selecting an appropriate moisturizer for AD patients. Other considerations include adjuvant properties of the product, cosmetic acceptability, and availability over the counter. Well-defined clinical phenotypes of AD could optimally benefit from specific moisturizers. It is hoped that future studies may identify such differences by means of filaggrin mutation subtypes, confocal microscopic evaluation, pH, transepidermal water loss or presence of allergy specific IgE. Recommendations to improve the regular use of moisturizers among AD patients include measures that focus on treatment compliance, patient and caregiver education, appropriate treatment goals, avoidance of sensitizing agents, and collaboration with other relevant specialists.
Adult ; Allergy and Immunology ; Asia, Southeastern ; Caregivers ; Classification ; Compliance ; Cooperative Behavior ; Dermatitis, Atopic ; Dermatology ; Education ; Hope ; Humans ; Hydrogen-Ion Concentration ; Hypersensitivity ; Immunoglobulin E ; Patient Compliance ; Pediatrics ; Phenotype ; Skin ; Specialization ; Water