Cell-mediated immunity to the mycelial phase of Malassezia spp. in patients with pityriasis versicolor and controls

BACKGROUND: Malassezia is the aetiological agent of pityriasis versicolor. The mycelial phase of the organism predominates in lesions of pityriasis versicolor. OBJECTIVES: To evaluate the cell-mediated immune (CMI) response to the mycelial phase of Malassezia in patients with this disease, which has not previously been studied. METHODS: The CMI status of 12 patients with pityriasis versicolor and 12 age- and sex-matched controls to mycelial antigen(s) of the organism was examined. The responses to the mycelial form of three strains of the organism were assessed using lymphocyte transformation and leucocyte migration inhibition assays. RESULTS: The transformation responses of the lymphocytes from both patients and controls gave transformation indices < or = 3, although the responses of lymphocytes from patients with pityriasis versicolor to the mycelial form of Malassezia strains were generally higher than those of the controls. In the leucocyte migration inhibition assay, leucocytes from patients with pityriasis versicolor and controls responded to the mycelial antigens of three different Malassezia strains; however, there was no significant difference in leucocyte response between patients with pityriasis versicolor and controls. CONCLUSIONS: Patients with pityriasis versicolor do not therefore have a CMI deficiency to Malassezia mycelial antigens but fail to generate a protective CMI response to mycelial antigens over and above that of control individuals during active disease.     

Epidemiology of pityriasis versicolor in Adana, Turkey

Pityriasis versicolor is a common superficial mycoses of the skin. It is now recognized that the causative organisms of this infection are different species of Malassezia . The aim of this study was to determine the distribution of Malassezia species in patients with pityriasis versicolor in Adana, Turkey. In total, 97 patients positive for Malassezia elements, namely, yeast cells and short hyphae in microscopic examination, were included in the study. All samples were inoculated in plates containing modified Dixon's medium. However, only 44 of the patients (45.4%) showed Malassezia spp. in culture. Malassezia globosa (47.7%) was the most commonly isolated species followed by Malassezia furfur (36.4%) and Malassezia slooffiae (15.9%). Mixed Malassezia species were not isolated. In conclusion, M. globosa was found to be the predominant PV isolate in Adana, Turkey.     

马拉色菌与花斑癣色素改变的相关性初探

目的探讨马拉色菌与花斑癣皮疹色素改变及色氨酸产色三者之间的关系.方法从花斑癣患者皮损分离马拉色菌株,采用国际通用的生化鉴定方法鉴定,然后在不同浓度L-色氨酸的培养基上培养7 d,观察产色反应.结果每个菌种均有产色反应阳性和阴性菌株,产色反应阳性菌株更易引起皮损色素沉着(P＜0.005),且产色反应阳性标本颜色按色氨酸浓度递减而变淡.结论菌株的产色反应与马拉色菌的种属分类无必然的联系,色氨酸参与了马拉色菌产色反应.     

Disruption of barrier function in dermatophytosis and pityriasis versicolor

Dermatophytes have the ability to form molecular attachments to keratin and use it as a source of nutrients, colonizing keratinized tissues, including the stratum corneum of the skin. Malassezia species also affect the stratum corneum of the skin. Therefore, dermatophytosis and pityriasis versicolor of the skin are thought to be important factors of profound changes in skin barrier structure and function. We aimed to describe the changes in transepidermal water loss (TEWL), stratum corneum hydration, and skin pH in the lesions of the dermatophytosis and pityriasis versicolor. Thirty-six patients with dermatophytosis (14 with tinea cruris, 13 with tinea corporis and nine with tinea pedis or tinea manus) and 11 patients with pityriasis versicolor were included in this study. TEWL, stratum corneum conductance and skin pH were determined by biophysical methods to examine whether our patients exhibited changes in barrier function. Dermatophytosis and pityriasis versicolor except tinea pedis and tinea manus showed highly significant increase in TEWL compared with adjacent infection-free skin. Hydration was significantly reduced in lesional skin compared with adjacent infection-free skin. From this study, infections with dermatophytes and Malassezia species on the body can alter biophysical properties of the skin, especially the function of stratum corneum as a barrier to water loss. On the contrary, infections with dermatophytes on the palms and soles little affect the barrier function of the skin.     

花斑癣患者血清中抗糠秕马拉色菌IgG、IgM、IgA抗体的检测及其意义

目的：探讨机体体液免疫在花斑癣发病中的作用和意义。方法：以糠秕马拉色菌（Ｍ．ｆｕｒｆｕｒ）整菌（ＷＭＦ）为抗原,用间接酶联免疫吸附试验（ＥＬＩＳＡ）方法,检测６８例花斑癣患者和４１例正常人血清中的抗ＷＭＦ抗体。结果：正常人血清中存在高滴度的抗ＷＭＦ抗体,花斑癣患者血清中抗ＷＭＦＩｇＧ抗体明显低于正常对照组（Ｐ〈０．０１）,男性患者血清中ＩｇＧ抗体低于女性患者（Ｐ〈０．０１）,病程１年以上者血清中特异的ＩｇＧ抗体低于病程不到１年者（Ｐ〈０．０１）。结论：机体血清抗Ｍ．ｆｕｒｆｕｒ抗体可能是人体内天然抗体,且特异的ＩｇＧ抗体具有保护作用。支持花斑癣的发病与免疫缺陷有关。     

花斑癣、马拉色菌毛囊炎、脂溢性皮炎马拉色菌诱发因素分析

目的调查昆明地区花斑癣、马拉色菌毛囊炎、脂溢性皮炎马拉色菌诱发因素,并比较三种疾病的诱发因素有无差异。方法收集花斑癣、马拉色菌毛囊炎、脂溢性皮炎(头皮屑)的病例,用自制的调查表对入选病例进行诱发因素调查,比较诱发因素在三种疾病间有无差异。结果共收集158例病例,男104例,女54例,平均年龄29.4岁,多汗、油性皮肤患者所占比例均超过60%,系统或局部使用糖皮质激素是马拉色菌毛囊炎的危险因素。结论马拉色菌感染好发于男性青壮年,多汗者易发生花斑癣,油性皮肤及使用糖皮质激素易发生马拉色菌毛囊炎。     

IgE antibodies to Malassezia furfur, M. sympodialis and Pityrosporum orbiculare in patients with atopic dermatitis, seborrheic eczema or pityriasis versicolor, and identification of respective allergens

Malassezia yeasts may be a trigger factor for atopic dermatitis. Following the recent reclassification of the genus, the presence of specific IgE antibodies was examined in the sera of patients with atopic dermatitis (n = 223), pityriasis versicolor (n = 83), seborrheic eczema (n = 50) and hymenoptera allergy (n = 39) and in controls without skin diseases (n = 50). In addition to using the commercially available radioallergosorbent test (RAST) for Pityrosporum orbiculare couplings were also made against the reference strains for M. furfur and M. sympodialis. To characterize the specificity and molecular weight of corresponding epitopes identical material was used for production of an immunoblot. Despite high total levels of IgE, controls and patients with pityriasis versicolor showed no specific IgE antibodies. Six patients (12%) with seborrheic eczema were positive while 78 patients (35%) with atopic dermatitis had specific IgE antibodies in higher RAST classes that differed between the Malassezia species. The molecular weights of the main antigens of M. sympodialis and M. furfur were determined to be 15, 22, 30, 37, 40, 58, 79, 92, 99 and 124 kDa and 15, 25, 27, 43, 58, 92, 99 and 107 kDa, respectively. Evaluated according to the location of their disease, patients with head and neck lesions most frequently showed Malassezia-specific IgE antibodies. However, there were differences between the Malassezia species tested, the previously used strain P. orbiculare being assignable to the species M. sympodialis.     

从花斑糠疹皮损分离的马拉色菌随机扩增多态性DNA研究

目的 用随机扩增多态性DNA方法研究分离自花斑糠疹的马拉色菌种间和株间差异,了解随机扩增多态性DNA分析（RAPD）与生理生化方法在菌种分型上的差异及菌株DNA型别和菌种间的关系。方法 用氯化苄法提取马拉色菌标准株（10株7个种）和临床分离株（47株）的基因组DNA,其中临床株分离自34例花斑糠疹患者,经形态学和生理生化方法鉴定为5个种（合轴马拉色菌、糠秕马拉色菌、钝形马拉色菌、球形马拉色菌、限制马拉色菌）,用4种随机引物（S22、S24、S25、S33）对菌株DNA做PCR随机扩增,NTSYS软件自动生成树状分支图。结果 绝大多数标本均可被4种引物扩增而获得清晰条带,其中2种引物（S22、S24）的条带更为稳定、清晰。共82条DNA片段被扩增,所有菌株均可见种间和株间多态性。有4例患者皮损同时分离出不同种的菌株显示遗传相似性高,在树状图中归入一类。结论 来自同一宿主的不同菌株遗传趋同现象提示马拉色菌的种特异性、菌种演化与宿主间存在密切关系。     

马拉色菌与人角质形成细胞株共同培养液对培养人黑素细胞生长及酪氨酸酶mRNA表达的影响

目的:观察不同马拉色菌与人角质形成细胞株共同培养液对培养人黑素细胞生长及酪氨酸酶mRNA表达的影响,探讨花斑癣的色素改变是否与马拉色菌的不同菌种有关。方法:将球形、钝形、糠秕、合轴马拉色菌分别与人角质形成细胞株共同培养,24 h后收集上清液,按一定比例加入黑素细胞培养体系中继续培养24 h:①用四甲基偶氮唑兰比色法观察对黑素细胞生长的影响;②用实时荧光定量PCR法测定黑素细胞酪氨酸酶mRNA的表达。结果:各共同培养液对黑素细胞生长无明显影响,但除球形马拉色菌与人角质形成细胞共同培养液可上调黑素细胞酪氨酸酶mRNA的表达(P<0.05)外,未见其它种马拉色菌与人角质形成细胞株共同培养液对黑素细胞酪氨酸酶mRNA的表达有影响。结论:球形马拉色菌与人角质形成细胞株共同培养液刺激黑素细胞后,能提高酪氨酸酶mR-NA的表达,该菌可能与花斑癣的色素沉着有关。     

Speziesdifferenzierung von Hefen der Gattung Malassezia mittels Fourier-Transform-Infrarot-Spektroskopie

BACKGROUND: 83 Malassezia strains (65 wild isolates and 18 reference strains) were differentiated to the species level using conventional methods including morphological and biochemical features. These strains were further analyzed by Fourier transform infrared spectroscopy (FT-IRS).RESULTS: FT-IRS analysis allowed a clear separation of Malassezia strains according to species-specific cluster formation. The main differences were found between Malassezia furfur and other Malassezia species. In addition, within the species Malassezia furfur, a separation in two similar groups could be demonstrated. A disadvantage of FT-IRS is the relatively expensive apparatus. A great advantage is the speed and simplicity of the procedure, producing results within minutes.CONCLUSION: In pityriasis versicolor, Malassezia globosa was the dominant species found in 62% of cases. In addition, Malassezia furfur was found in 60% of dandruff cases.     

Cell-mediated immunity to Malassezia furfur in patients with seborrhoeic dermatitis and pityriasis versicolor

The lymphocyte transformation response to Malassezia furfur, Candida albicans, phytohaemagglutinin, concanavlin A and tuberculin purified protein derivative of 12 patients with pityriasis versicolor, 15 patients with seborrhoeic dermatitis and matched controls, was studied. Patients with pityriasis versicolor showed a significantly lower response to M. furfur than patients with seborrhoeic dermatitis and controls.     

从花斑癣患者的皮损区及非皮损区分离和鉴定马拉色菌

目的 研究花斑癣患者皮损区及非皮损区马拉色菌菌种构成;不同解剖部位、皮损颜色及各菌种的分布情况;患者病情和年龄与菌种构成的关系。方法 用无菌胶带粘取113例花斑癣患者皮损区及非皮损区共629个部位的皮屑,分别接种于含菜子油培养基中分离马拉色菌,用生理生化及形态学方法鉴定菌种。结果 皮损区与相对应的非皮损区马拉色菌分离阳性率无差别,非皮损区额部和胸背部分离阳性率高于上、下肢。共分离到565株马拉色菌,鉴定出合轴马拉色菌(44.78%)、糠秕马拉色菌(32.94%)、球形马拉色菌(11.68%)、钝形马拉色菌(5.84%)及限制马拉色菌(4.76%)共5个种,有27处(5.01%)同时分离到两种菌。皮损区与非皮损区菌种构成无明显差别,限制马拉色菌主要从额部分离出。菌种构成与皮损面积无关,但与皮损颜色和患者年龄有关。皮损颜色与病程无关。结论 花斑癣患者皮损区与非皮损区马拉色菌分离阳性率和菌种构成基本一致,与病情无关,而不同解剖部位、皮损类型及年龄患者的菌种构成有一定差异。     

Molecular analysis of Malassezia microflora in seborrheic dermatitis patients: comparison with other diseases and healthy subjects

Malassezia species colonize the skin of normal and various pathological conditions including pityriasis versicolor (PV), seborrhoeic dermatitis (SD) and atopic dermatitis (AD). To elucidate the pathogenic role of Malassezia species in SD, Malassezia microflora of 31 Japanese SD patients was analyzed using a PCR-based, culture-independent method. Nested PCR assay using the primers in the rRNA gene indicated that the major Malassezia species in SD were M. globosa and M. restricta, found in 93 and 74% of the patients, respectively. The detection rate and number of each species varied similarly in SD, PV and healthy subjects (HSs), whereas AD showed higher values. Real-time PCR assay showed that the lesional skin harbored approximately three times the population of genus Malassezia found in nonlesional skin (P<0.05), and that M. restricta is a significantly more common species than M. globosa in SD (P<0.005). Genotypic analysis of the rRNA gene showed that the M. globosa and M. restricta from SD patients fell into specific clusters, and could be distinguished from those collected from HSs, but not from those colleted from AD patients. Our results indicate that certain strains of M. restricta occur in the lesional skin of SD patients.     

Fluconazole and itraconazole in pityriasis versicolor

Pityriasis versicolor is a common superficial fungal infection caused by Malassezia species. It has a high incidence and prevalence in tropical climates. Although it responds well to treatment, relapses and recurrences are frequent. In the present study the therapeutic response of single dose fluconazole (400 mg) with itraconazole (100mg twice daily ? 7 days) was compared in sixty patients of pityriasis versicolor. No significant statistical difference (p>0.05%) was observed between efficacy of two drugs. Therapy with fluconazole is preferable in view of single dose administration and lesser cost as compared to itraconazole.     

花斑糠疹和马拉色菌毛囊炎菌种分布特点分析

目的探讨花斑糠疹和马拉色菌毛囊炎的菌种分布特点。方法从临床诊断为花斑糠疹和马拉色菌毛囊炎的患者分离培养菌种,通过形态学和生理生化学方法鉴定菌种,并比较两组患者菌种分布情况。结果共收集花斑糠疹病例161例,培养阳性121株,其中合轴马拉色菌46株,糠秕马拉色菌13株,球形马拉色菌29株,钝性马拉色菌33株;马拉色菌毛囊炎135例,培养阳性114株,其中合轴马拉色菌52株,糠秕马拉色菌43株,球形马拉色菌13株,钝性马拉色菌6株。两种疾病菌种分布差异有显著性(P<0.005)。结论花斑糠疹和马拉色菌毛囊炎菌种分布存在差异,可能为两种疾病不同临床表现的原因之一,但结果尚需慎重解释,需要分子水平的进一步研究。     

Pityriasis versicolor alba

Pityriasis versicolor alba is a hypopigmented or depigmented variant of pityriasis versicolor characterized by maculous, partly pityriasiform, scaly depigmented lesions occurring particularly in seborrhoeic areas. Long-persisting hypopigmentation after healing of the pityriasis versicolor was first described by Gudden in 1853. Hypopigmentation and depigmentation were later differentiated as an independent variant of the disease. In 1848, Eichstedt recognized the pathogen-related character of pityriasis versicolor in its hyperpigmented form. Today it is generally accepted that the disease is caused by yeasts of the genus Malassezia, of which nine species are differentiated. It is controversial whether a single species is responsible for the disease. The pathogenesis of depigmentation has not been established. A screening effect by the scale layer as well as toxic effects on pigment synthesis by fungal metabolites have been discussed. With regard to the second mechanism, the newly discovered tryptophan-derived metabolites of M. furfur might be significant. Evidence-based data concerning the therapy of pityriasis versicolor alba do not exist. According to current recommendations, pityriasis versicolor should be rapidly treated with antimycotics, followed by ultraviolet therapy to induce maturation of existent melanosomes and accelerate repigmentation. However, depigmented lesions are difficult to improve by ultraviolet therapy.     

Skin diseases associated with Malassezia species

The yeasts of the genus Malassezia have been associated with a number of diseases affecting the human skin, such as pityriasis versicolor, Malassezia (Pityrosporum) folliculitis, seborrheic dermatitis and dandruff, atopic dermatitis, psoriasis, and--less commonly--with other dermatologic disorders such as confluent and reticulated papillomatosis, onychomycosis, and transient acantholytic dermatosis. Although Malassezia yeasts are a part of the normal microflora, under certain conditions they can cause superficial skin infection. The study of the clinical role of Malassezia species has been surrounded by controversy because of their fastidious nature in vitro, and relative difficulty in isolation, cultivation, and identification. Many studies have been published in the past few years after the taxonomic revision carried out in 1996 in which 7 species were recognized. Two new species have been recently described, one of which has been isolated from patients with atopic dermatitis. This review focuses on the clinical, mycologic, and immunologic aspects of the various skin diseases associated with Malassezia. It also highlights the importance of individual Malassezia species in the different dermatologic disorders related to these yeasts.     

Distribution of Malassezia species in pityriasis versicolor and seborrhoeic dermatitis in Greece. Typing of the major pityriasis versicolor isolate M. globosa

BACKGROUND: The expansion of the genus Malassezia has generated interest in the epidemiological investigation of the distribution of new species in a range of dermatoses, on which variable results have been reported from different geographical regions. No data are thus far available from South-east Europe (Greece). OBJECTIVES: To study the distribution of Malassezia species in pityriasis versicolor (PV) and seborrhoeic dermatitis (SD) and to investigate whether polymorphisms in the internal transcribed spacer (ITS) 1 region facilitate detection of M. globosa and M. sympodialis subtypes. METHODS: In total, 109 patients with PV and SD and positive Malassezia cultures were included in the study. Age, gender, primary/recurrent episode, disease extent and clinical form of PV were recorded. ITS 1 polymorphisms of M. globosa and M. sympodialis type and clinical strains were investigated by polymerase chain reaction (PCR)-single-strand conformational polymorphism (SSCP) analysis. RESULTS: Malassezia globosa was the prevalent species isolated from PV and SD either alone (77% and 39%, respectively) or in combination (13% and 18%, respectively) with other Malassezia species. The pigmented form of PV was strongly correlated with the female gender. PCR-SSCP differentiated five subgroups of M. globosa with one being associated with extensive clinical disease. All M. sympodialis isolates displayed a homogeneous ITS 1 PCR-SSCP profile. CONCLUSIONS: Malassezia species isolation rates were in agreement with those reported from South-west Europe. PCR-SSCP of the ITS 1 is useful for highlighting prospective clinical implications of M. globosa subtypes.     

Pityriasis (Tinea) Versicolor in Infancy

Pityriasis (tinea) versicolor is a common disorder of adults. We cared for five infants (four males and one female) with the disease. Diagnosis was confirmed by potassium hydroxide preparation demonstrating the filaments of Malassezia furfur and/or Pityrosporum orbiculare, the yeast form. Three patients had lesions in the neonatal period. The mother of one baby had pityriasis versicolor. Two patients were siblings. One baby had associated atopic dermatitis and two had a positive family history of atopy.     

Susceptibility of Malassezia furfur subgroups to terbinafine

Summary Malassezia furfur , the fungus causing pityriasis versicolor. has been reported to be sensitive to terbinafine in vitro but although topical therapy is effective in the treatment of pityriasis versicolor. oral therapy is not. This phenomenon was investigated by determining the susceptibility to terbinafine of different M. furfur subgroups in vivo (during topical or oral application) and in vitro. All M. furfur subgroups were suppressed (∼ 10-fold) by topical terbinafine. Oral treatment resulted in no significant suppression of cutaneous M. furfur populations with the exception of a single subgroup (A), which was reduced to undetectable levels on the skin of eight of 10 patients receiving oral terbinafine. Isolates of subgroup A were also markedly more susceptible to terbinafine in laboratory tests. The importance of the recognition of distinct subgroups within the cutaneous lipophilic yeasts when evaluating their antifungal susceptibility and their role in disease is discussed.