Contact sensitivity to Pityrosporum ovale in patients with atopic dermatitis

Contact sensitivity and immediate hypersensitivity to extracts from Pityrosporum ovale were studied in patients with atopic dermatitis (AD). In a chamber-scarification patch test, 75 (64%) of 118 patients with AD responded positively, compared with 1 (3%) of 35 healthy volunteers. However, no significant statistical correlations were found between contact sensitivity to P ovale in patients with AD and any of the following factors: age, sex, distribution of skin lesions, presence of pruriginous papules, history of infantile seborrheic dermatitis, or concomitance of other atopic diseases. Lymphocyte transformation test with P ovale antigen confirmed that those with positive patch test reactions showed significantly high stimulation indexes. The antigenic substances divided by gel filtration high-performance liquid chromatography were found in a fraction of components with molecular weights above 60 kd. In addition, 25 (71%) of 35 patients with AD showed a positive immediate response to P ovale extract in a prick test, whereas none of 11 healthy volunteers showed any response. Although the incidence of the positive immediate responses was similar to that in contact sensitivity, there was no clear correlation between the delayed and immediate hypersensitivity reactions. Based on these results, we think that P ovale plays a role as an allergen derived from the host environment in the exacerbation of the skin lesions of AD.     

IgE antibodies to Pityrosporum ovale in atopic dermatitis

An enzyme-linked immunosorbent assay (ELISA) was developed to assess serum IgE antibodies directed against Pityrosporum ovale in patients with atopic dermatitis (AD), atopic patients with allergic respiratory disease (ARD: rhinitis or asthma) but without eczema, and in healthy controls. IgE binding to P. ovale extract was demonstrated in 49% (35/72) of AD patients. In contrast, anti-P. ovale IgE was found in only one of 27 atopic controls without eczema; all healthy control sera (n = 17) were negative. Of 37 AD patients tested intracutaneously with P. ovale, 31 showed immediate-type reactivity, and 20 of these 31 patients had anti-P. ovale IgE detectable by ELISA, while sera from the six non-responders were all negative. Levels of anti-P. ovale IgE were highest in AD patients aged 20-30 years. No correlation was found with the severity of AD, but there was a non-significant tendency (P = 0.06) to higher levels in AD patients with concomittant respiratory allergy. Anti-P. ovale IgE was significantly correlated with total serum IgE, with specific IgE against various aeroallergens as measured by RAST, and with levels of anti-Candida albicans IgE, measured with a similar ELISA. Thus, production of IgE antibodies against P. ovale occurs very frequently in AD, and rarely in patients with atopic disease without skin involvement.     

Chemotactic lipoxygenase products in sera from patients with psoriasis

Summary Sera obtained from 12 patients with moderate to severe psoriasis were investigated for the presence of arachidonate lipoxygenase metabolites using reverse-phase high-performance liquid chromatography after extraction on silicic acid columns. Peaks which co-chromatographed with standards of synthetic leukotriene B₄ (LTB₄) were collected, and the material was tested for chemotactic activity. In the sera of 5 of the patients, chemotactic activity was demonstrable in these LTB₄ peaks. Although minor peaks cochromatographing with LTB₄ were found in control sera, none of them contained chemotactic material. Isolated monocytes from the psoriasis patients showed enhanced chemotactic activity as compared to monocytes obtained from healthy controls. The results of our study support the view that abnormal 5-lipoxygenase activity is present in psoriasis. Further investigation is required to determine whether LTB₄ is released from circulatory leukocytes or the skin.     

Pityrosporum ovale in Infantile Seborrheic Dermatitis

The presence of Pityrosporum ovale was investigated in four groups of infants age 1 to 24 months, 15 with infantile seborrheic dermatitis, 15 with infantile atopic dermatitis, 15 with other infantile dermatoses, and 15 healthy infants. Samples were taken from the scalp, face, presternal area, and inguinal area. Pityrosporum ovale was detected by smears and/or cultures in 73% of infants with seborrheic dermatitis, 33% with atopic dermatitis, 33% with other dermatoses, and 53% of healthy infants. The percentages of positive smears and/or cultures from four body sites in each patient group were 42% for seborrheic dermatitis, 20% for atopic dermatitis, 20% for other infantile dermatoses, and 23% for healthy infants. The majority of infants with positive cultures or positive direct examination for P. ovale were between 1 and 8 months of age. The organism was isolated in 28% of samples taken from the scalp, 32% from the face, 30% from the presternal area, and 15% from the inguinal area. Patients with infantile seborrheic dermatitis were treated with 2% topical ketoconazole cream for two weeks. Eleven of these children were clinically cleared and 13 became mycologically negative. Pityrosporum ovale was significantly more frequent in infants with seborrheic dermatitis than in those with atopic dermatitis, in other infantile dermatoses, or in healthy infants, both in the total number of infants with positive smears and/or cultures and in the number of positive samples per body area (P less than 0.05).     

Antibodies to Pityrosporum orbiculare in patients with tinea versicolor and controls of various ages

Sera from patients with tinea versicolor and controls of various ages were investigated with the indirect immunofluorescence technique for antibodies against Pityrosporum orbiculare, the etiologic agent of tinea versicolor. No differences in titers were observed between patients and adult controls. Also, there were no differences in antibody titers in the patient group with regard to age and sex, or to duration and distribution of lesions. A statistically significant difference in antibody titers was observed between adult controls and children, particularly the youngest. Antibodies against Candida albicans from randomly selected sera from the same groups showed the same tendency, although only statistically significant when children of 5 years or younger were compared with adult controls. This investigation indicates that although P. orbiculare is capable of inducing antibodies, these are not correlated to tinea versicolor but occur when an individual becomes colonized with the organism.     

33例银屑病病人6种抗磷脂抗体的检测

目的：探讨抗磷脂抗体(APA)与银屑病的关系。方法：应用酶联免疫吸附试验(ELISA)检测33例银屑病和16例梅毒病人血中6种APA。结果：①银屑病病人IgG型aCL、aPA、aPS、aPC和aPI的A值和aPI的阳性率较正常人显著升高；IgM型APA的A值较正常人显著降低，均阴性；②梅毒病人IgG型aCL、aPA、aPE和aPI的A值和aCL、aPA的阳性率较正常人显著升高；IgM型aCL、aPS、aPE和aPC的A值和aCL、aPS、aPE、aPC和aPI的阳性率较正常人显著升高。结论：在银屑病时存在APA的机制与梅毒不同。     

Pityrosporum ovale in keratotic lesions of seborrheic areas

The Pityrosporum ovale (PO) is demonstrated in various percentages of the keratotic lesions of the seborrheic areas depending upon the techniques. The accumulation of horny material most probably enhances the multiplication of the yeast and makes its demonstration easier. The PAS technique prevails upon the mycological ones (77 p. 100 versus 50-65 p. 100). PO proliferates only in the keratin layer; there are isolated spores, small clusters or even large stratified colonies. On the other side the prevalence of PO does not differ significantly whatever the ultimate diagnosis of seborrheic keratosis, actinic keratosis, naevocellular nevus or vial wart. Its multiplication within the keratin layer of the lesions does not make any difference as far as the lymphocytic infiltration of the dermis is concerned.     

银屑病患者血清食物变应原特异性IgE、IgG的检测

目的 探讨银屑病患者食物变应原特异性IgE、IgG的检测结果。方法 对102例银屑病患者进行了食物变应原特异性IgE、IgG检测,同时对慢性湿疹患者、慢性荨麻疹患者、健康体检者进行检测。结果银屑病、慢性湿疹、慢性荨麻疹患者3组间食物特异性IgE、食物特异性IgG检测的阳性例数比较,差异均无统计学意义。银屑病、慢性湿疹、慢性荨麻疹患者分别与健康体检组的阳性例数比较,差异均有统计学意义。结论 食物变应原与银屑病的致病有关,银屑病与慢性湿疹、慢性荨麻疹患者变应原来源和种类不一,值得进一步研究。     

银屑病患者血清抗EB病毒抗体的检测

目的：探讨EB病毒感染与银屑病的关系。方法：采用酶免疫法检测53例银屑病患者血清EB病毒抗壳抗原／IgG、IgM抗体，抗早期抗原－D／IgG抗体。抗核心抗原－1／IgG抗体。结果：银屑病患者血清抗ER病毒早期抗原－D／IgG抗体阳性率明显高于正常对照组（P＜0．001）。结论：银屑病患者体内EB病毒可能处于激活状态。     

Differential T-cell reactivity to the round and oval forms of Pityrosporum in the skin of patients with psoriasis

Pityrosporum yeasts have been implicated as a trigger for the initiation of scalp lesions in psoriasis. To determine whether Pityrosporum-reactive T cells are present in lesional psoriatic skin. T-cell lines (TCL) were cultured from the scalps of nine patients with psoriasis and seven with alopecia areata (disease controls), and from non-scalp lesions from six of the psoriatic patients. The psoriatic skin TCL were stained for CD3, CD4, CD8 and TCR αβ expression and tested in a proliferation assay with Candida albicans and purified protein derivative (PPD), and cytoplasmic and cell-wall extracts of P. ovale (oval) and P.orbiculare (round). The proliferative responses of corresponding peripheral blood mononuclear cells (PBMC) were also determined. All the PBMC samples responded to the Pityrosporum extracts to variable extents, but no significant difference in the response of the group to the two different forms of yeast was observed. The response was mediated by CD4⁺ T cells and inhibited by the addition of anti-HLA-DR antibody. In addition, all nine psoriatic scalp TCL, which were predominately CD3⁺, CD4⁺ TCR αβ⁺, responded to the cytoplasmic, and five of nine TCL to the cell-wall extract of P. orbiculare. In contrast, only three of the nine TCL proliferated to either extract of P. ovale. This difference was significant for both the cytoplasmic (P < 0.01) and cell wall (P = 0.01) extracts. Similarly, the TCL cultured from non-scalp psoriatic lesions also showed a more marked response to the P. orbiculare extracts (P = 0.05). Furthermore, four of seven and two of seven scalp TCL from lesions of alopecia areata responded to the P. orbiculare and P. ovale extracts, respectively; these responses did not differ significantly from those of the psoriatic scalp TCL. None of the skin TCL responded to either Candida albicans or PPD. These findings demonstrate that T cells with differential reactivity to the round and oval forms of Pityrosporum are present in, but are not specific for, psoriatic skin lesions. A role for these cells in the pathogenesis of psoriasis remains speculative.     

Increased Hair Shedding May be Associated with the Presence of Pityrosporum ovale

Background and objective: Although the available data show that hair loss is an important cosmetic problem worldwide, the pathogenesis of common hair shedding is not fully understood. The aim of this study was to evaluate the association between hair shedding and cutaneous Malassezia infection. Malassezia fungi have been the suspected cause of dandruff for more than a century. Previously referred to as Pityrosporum ovale or P. orbiculare, these fungi are now known to consist of at least seven species. Methods: Over a 4-year period, we obtained 300 hair samples from medical students. Based on the clinical history and a hair-pull test, the participants were divided into two groups: normal subjects and subjects with hair shedding. The students’ scalp skin was gently scraped, smeared on a slide, colored by methylene blue, and observed under 10× magnification. Results: All participants who had positive smears with ≥3 P. ovale organisms per low-power microscopic field (10×) were defined as ‘ecarriers.’ Seventy-six percent of students were Malassezia carriers. The prevalence of positive smears was significantly higher among subjects with hair shedding than among normal subjects (89.92% vs 9.52%, p < 0.001). Furthermore, participants with positive smears had a significantly higher frequency of hair loss complaints and positive hair-pull tests. Conclusion: The proportion of subjects who were carriers of Malassezia yeasts was significantly higher in the group with hair shedding, and our results therefore raise the possibility of a relationship between this unicellular organism and hair loss. Our study findings should be explored in a larger series of patients.     

从一例甲真菌病患者病甲中分离出糠秕孢子菌临床和实验研究

从一例甲真菌病患者的病甲标本中分离出糠秕孢子菌 ,并进行了培养、组织病理、扫描电镜、溶甲等研究。患者为 6 4岁女性 ,因指趾甲变色、增厚、粗糙 2 0余年就诊。体检见各指、趾甲增厚变色 ,表面粗糙不平 ,指甲前端甲板与甲床分离。指甲培养结果发现在沙堡培养基有红色毛癣菌生长 ,在含菜子油培养基有卵形糠秕孢子菌生长。病理检查发现甲组织裂隙中有卵形出芽孢子 ,扫描电镜观察见大量有颈圈样结构的卵形出芽孢子镶嵌于甲组织中。 2 0 %KOH、5 6℃处理 1小时的甲沉淀物涂片经Parker墨水染色后镜下可见与卵形糠秕孢子菌和红色毛癣菌形态一致的孢子和菌丝。患者接受伊曲康唑间歇冲击治疗 ,第四疗程结束后 1～ 2月时甲颜色明显光亮 ,以后未见进一步好转。治疗结束后 6个月时再剪病甲培养又有红色毛癣菌和卵形糠秕孢子菌生长。结论　此为国内首次报道卵形糠秕孢子菌与甲真菌病有关。复习文献 ,对红色毛癣菌和卵形糠秕孢子菌在发病中的地位进行了讨论。     

Increased superoxide generation by normal granulocytes incubated in sera from patients with psoriasis

Sera from patients with untreated psoriasis were found to induce increased superoxide anion (O-2) generation when incubated with normal granulocytes (PMNs) and zymosan. Sera from patients receiving systemic chemotherapy induced O-2 generation which was similar to that of normal sera and significantly lower than sera from the untreated patients. O-2 production was measured by superoxide dismutase inhibitable ferricytochrome C reduction and was dependent on the presence of both zymosan and a heat labile serum factor. Serum C3c and C5 levels were elevated in both treated and untreated groups of psoriasis patients while C4 was elevated only in untreated patients. serum ceruloplasmin, a O-2 scavenger, was not decreased in patients with psoriasis, and consequently does not account for the increased O-2 generation. These data suggest that sera from patients with psoriasis have an increased capacity to activate PMNs. Activation of PMNs in cutaneous and joint lesions may play a pathogenic role in psoriasis.     

Pityriasis pigmentosa: the clinical features of pathogenic Pityrosporum ovale

This paper proposes a new skin disease entity—pityriasis pigmentosa. Characteristic lesions of this disease are well defined, oval or round, pigmented patches covered with fine, adherent, wrinkled scales. The size of the lesions varies from 0.5–3 cm in diameter. Some lesions gyrate or coalesce into larger patches. The lesions are typically located on the waist and the extremities and are particularly common on the volar aspect of the upper arms and the posterior aspect of the upper thighs. Using Wood's light examination, a bright golden fluorescence is inevitably seen. Rapid identification can be made by use of the KOH/Parker Ink preparation. This reveals characteristic branched, segmented hyphae and clusters of budding, oval-shaped yeast cells. Pityrosporum ovale produces hyphae when cultured in glycine-ammonium phosphate buffered media. Pityrosporum orbiculare does not produce hyphae by this method. These clinical and laboratory findings distinguish a clinical entity differing from Tinea (Pityriasis) versicolor which is caused by Pityrosporum orbiculare.     

Pityrosporum ovale/orbiculare in papillomatous nevus cell nevi.

62% of 200 papillomatous nevus cell nevi compared to 45% of 40 seborrheic keratoses showed the presence of Pityrosporum ovale/orbiculare (Malassezia furfur) on their surface, supposedly representing a saprophytic state of the microorganisms in vivo. The papillomatous nevus cell nevi were of the compound or dermal type. Significant inflammation, dysplasia or major changes in color were absent. Electron microscopy revealed the characteristic, sometimes budding fungal cells. A relationship between the presence of Pityrosporum organisms and papillomatosis is discussed.