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Jan Faergemann - One of the best experts on this subject based on the ideXlab platform.
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seborrhoeic dermatitis and Pityrosporum malassezia Folliculitis characterization of inflammatory cells and mediators in the skin by immunohistochemistry
British Journal of Dermatology, 2001Co-Authors: Jan Faergemann, Im Bergbrant, M Dohse, A Scott, G WestgateAbstract:Background The fact that Pityrosporum ovale plays a part in seborrhoeic dermatitis is well established but the mechanism of this relationship has not been established. Objectives To compare the number and type of inflammatory cells and mediators in skin biopsies from normal and lesional skin from the trunk and scalp in patients with seborrhoeic dermatitis, Pityrosporum (Malassezia) Folliculitis and in normal skin from healthy controls. Methods The skin biopsies were stained using the labelled Streptavidin-biotin method. The following markers were studied: CD4, CD8, CD68, HLA-DR, NK1, CD16, Clq, C3c, IgG, CD54 (ICAM-1), interleukin (IL) -1α, IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, tumour necrosis factor-a and interferon-γ. Results HLA-DR+ cells were seen in the highest number, and were higher in lesional skin compared with normal skin from both patients and healthy volunteers, ICAM-1 expression was also increased in lesional skin. Clq and the interleukins showed an increased cellular and intercellular staining in patients compared with healthy controls and the intercellular staining was often more intense in lesions compared with non-lesional skin. Staining was often more intense when Malassezia (Pityrosporum ovale) yeast cells were present. Conclusions An increase in NK1+ and CD16+ cells in combination with complement activation indicates that an irritant non-immunogenic stimulation of the immune system is important. The result with the interleukins showed both an increase in the production of inflammatory interleukins as well as in the regulatory interleukins for both T H 1 and T H 2 cells. Similarities to the immune response described for Candida albicans infections indicate the role of Malassezia in the skin response in seborrhoeic dermatitis and Pityrosporum Folliculitis.
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Pityrosporum yeasts--what's new?
Mycoses, 1997Co-Authors: Jan FaergemannAbstract:The lipophilic yeast Pityrosporum ovale is a member of the normal human cutaneous flora in adults but also associated with several skin diseases. In pityriasis versicolor, under the influence of predisposing factors, P. ovale changes from the round blastospore form to the mycelial form. A great problem in pityriasis versicolor is the high rate of recurrence and to avoid this a prophylactic treatment is mandatory. Pityrosporum Folliculitis is a chronic disease characterized by pruritic follicular papules and pustules located primarily on the upper trunk, neck and upper arms. In direct microscopy clusters of round budding yeast cells are found. The disease responds rapidly to antimycotic therapy. There are now many studies indicating that P. ovale plays an important role in seborrhoeic dermatitis. Many of these are treatment studies showing a good effect of antimycotics paralleled by a reduction in number of organisms. Severe seborrhoeic dermatitis often difficult to treat is associated with AIDS. In peripheral blood from a high number of patients with seborrhoeic dermatitis we found an increase in number of natural killer T-cells and decreased PHA and Con-A stimulation. Secondary we found low serum IgG antibody titres in patients compared to controls. Other studies have found a reduced lymphocyte stimulation reaction when lymphocytes from patients with seborrhoeic dermatitis were stimulated with a P. ovale extract. Additionally, IL-2 and IFN gamma production by lymphocytes from patients was markedly depressed and IL-10 synthesis were increased after stimulation with P. ovale extract. The majority of adult patients with atopic dermatitis localized to the head, neck and scalp are prick-test positive to a protein P. ovale extract. One study showed that p. ovale extracts increased IL-4, IL-10 and IgE synthesis in patients with atopic dermatitis. There are also treatment studies indicating that antifungal treatment may be beneficial in these patients.
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An immunological study in patients with seborrhoeic dermatitis.
Clinical and experimental dermatology, 1991Co-Authors: Im Bergbrant, Jan Faergemann, S. Johansson, D. Robbins, Annika Scheynius, T. SöderströmAbstract:The humoral and cellular immune-status was studied in 30 patients with seborrhoeic dermatitis. Increased frequencies of natural killer cells were found in 46% of patients. Furthermore, subnormal mitogen stimulation responses were demonstrated in 13 patients, whereas two individuals were found to have very high numbers of activated T lymphocytes in peripheral blood. Higher-than-normal total serum IgG and IgA was observed in 14 and 11 patients, respectively. For nine of 12 patients with skin lesions, dermal perivascular cell infiltrates were seen. The majority of the infiltrating cells reacted with anti-CD4 antibodies. HLA-DR-expressing keratinocytes were found in two biopsies. The study suggests that patients with seborrhoeic dermatitis may have depressed T-cell function. This could have a bearing on their susceptibility to the Pityrosporum ovale-associated dermatitis. The very high frequencies of activated T cells observed in the peripheral blood of two otherwise healthy seborrhoeic individuals suggests that intermittent systemic immune activation may occur. Seborrhoeic dermatitis is a common skin disease. It can be diagnosed by its characteristic red to yellow-brown lesions covered with greasy scales distributed in areas with a high number of sebaceous glands, such as the scalp, face and upper trunk. There is an association between seborrhoeic dermatitis and the lipophilic yeast Pityrosporum ovale but its exact aetiological role is not known. The yeast is a member of the normal cutaneous flora but also the aetiological agent of pityriasis versicolor and Pityrosporum Folliculitis. P. ovale can activate complement via the direct and alternative pathways. This may play some part in the induction of inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)
Faergemann J - One of the best experts on this subject based on the ideXlab platform.
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Pityrosporum ovale and skin diseases.
The Keio journal of medicine, 1993Co-Authors: Faergemann JAbstract:Pityrosporum ovale is a lipophilic yeast belonging to the normal human cutaneous flora in adults. It is not only a saprophyte but also an opportunistic pathogen associated with: Pityriasis versicolor, Pityrosporum Folliculitis, seborrhoeic dermatitis and some forms of atopic dermatitis. Even systemic infections have been described. In pityriasis versicolor P. ovale change from the blastospore to the mycelial form under the influence of predisposing factors such as high temperature, high relative humidity or endogenous factors such as greasy skin, sweating, heredity, immunosuppressive treatment or disorders. Topical treatment is often effective but short term treatment with fluconazole, ketoconazole or itraconazole is also effective. The great problem is recurrence and to avoid this a prophylactic treatment is mandatory. Pityrosporum Folliculitis is a chronic disease characterized by pruritic follicular papules and pustules located primarily on the upper trunk, neck and upper arms. Under the influence of the same predisposing factors as in pityriasis versicolor P. ovale increase in numbers in the hair follicles. The main differential diagnosis is acne vulgaris. The effect of antifungal treatment is often dramatic. There are now many studies indicating that P. ovale plays an important role in seborrhoeic dermatitis. Many of these are treatment studies showing a good effect of antimycotics parallelled by a reduction in number of P. ovale. Severe seborrhoeic dermatitis often difficult to treat is associated with AIDS. In a recent study we have evidence for a slight T-cell defect in many patients with seborrhoeic dermatitis.(ABSTRACT TRUNCATED AT 250 WORDS)
G Westgate - One of the best experts on this subject based on the ideXlab platform.
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seborrhoeic dermatitis and Pityrosporum malassezia Folliculitis characterization of inflammatory cells and mediators in the skin by immunohistochemistry
British Journal of Dermatology, 2001Co-Authors: Jan Faergemann, Im Bergbrant, M Dohse, A Scott, G WestgateAbstract:Background The fact that Pityrosporum ovale plays a part in seborrhoeic dermatitis is well established but the mechanism of this relationship has not been established. Objectives To compare the number and type of inflammatory cells and mediators in skin biopsies from normal and lesional skin from the trunk and scalp in patients with seborrhoeic dermatitis, Pityrosporum (Malassezia) Folliculitis and in normal skin from healthy controls. Methods The skin biopsies were stained using the labelled Streptavidin-biotin method. The following markers were studied: CD4, CD8, CD68, HLA-DR, NK1, CD16, Clq, C3c, IgG, CD54 (ICAM-1), interleukin (IL) -1α, IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, tumour necrosis factor-a and interferon-γ. Results HLA-DR+ cells were seen in the highest number, and were higher in lesional skin compared with normal skin from both patients and healthy volunteers, ICAM-1 expression was also increased in lesional skin. Clq and the interleukins showed an increased cellular and intercellular staining in patients compared with healthy controls and the intercellular staining was often more intense in lesions compared with non-lesional skin. Staining was often more intense when Malassezia (Pityrosporum ovale) yeast cells were present. Conclusions An increase in NK1+ and CD16+ cells in combination with complement activation indicates that an irritant non-immunogenic stimulation of the immune system is important. The result with the interleukins showed both an increase in the production of inflammatory interleukins as well as in the regulatory interleukins for both T H 1 and T H 2 cells. Similarities to the immune response described for Candida albicans infections indicate the role of Malassezia in the skin response in seborrhoeic dermatitis and Pityrosporum Folliculitis.
Karen Wiss - One of the best experts on this subject based on the ideXlab platform.
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Pityrosporum Folliculitis: A retrospective review of 110 cases
Journal of the American Academy of Dermatology, 2017Co-Authors: Brea Prindaville, Leah Belazarian, Nikki A. Levin, Karen WissAbstract:Background Pityrosporum Folliculitis is an under-recognized eruption of the face and upper portion of the trunk that may be confused with, or occur simultaneously with, acne vulgaris. Objective We sought to characterize risk factors for Pityrosporum Folliculitis, its clinical presentation, and its response to treatment. Methods A retrospective chart review was performed on all patients age 0 to 21 years seen at our facility from 2010 to 2015 with Pityrosporum Folliculitis confirmed by a potassium hydroxide preparation. Results Of 110 qualifying patients, more than 75% had acne that had recently been treated with antibiotics, and when recorded, 65% reported pruritus. Clinical examination demonstrated numerous 1- to 2-mm monomorphic papules and pustules that were typically on the forehead extending into the hairline and on the upper portion of the back. The most common treatment was ketoconazole shampoo, which led to improvement or resolution in most cases. Some patients required oral azole antifungals. Limitations This study was retrospective and relied on providers describing and interpreting the clinical findings and potassium hydroxide preparations. No standard grading system was used. Conclusion Unlike classic acne vulgaris, Pityrosporum Folliculitis was more common after antibiotic use. It presented as fine monomorphic, pruritic papules and pustules along the hairline and on the upper portion of the back, and it improved with topical or oral azole antifungal therapy.
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Pityrosporum Folliculitis: diagnosis and management in 6 female adolescents with acne vulgaris.
Archives of pediatrics & adolescent medicine, 2005Co-Authors: Katherine Ayers, Susan M. Sweeney, Karen WissAbstract:Background Pityrosporum Folliculitis is a common inflammatory skin disorder that may mimic acne vulgaris. Some adolescents with recalcitrant follicular pustules or papules may have acne and Pityrosporum Folliculitis simultaneously. Clinical response is dependent on treating both conditions. Objectives To demonstrate the similarity in clinical manifestation between acne vulgaris and Pityrosporum Folliculitis, the benefit of potassium hydroxide preparation, and the benefit of appropriate antifungal therapy. Patients We describe 6 female adolescents with concurrent Pityrosporum Folliculitis infection and acne vulgaris. Intervention A potassium hydroxide examination was performed on all 6 patients from the exudate of follicular pustules exhibiting spores consistent with yeast. All patients were treated with oral antifungals, and 5 of the 6 patients were also treated with topical antifungals. Results Six of 6 patients improved with antifungal treatment. All patients also required some ongoing therapy for their acne. Conclusions These patients demonstrate that follicular papulopustular inflammation of the face, back, and chest may be due to a combination of acne vulgaris and Pityrosporum Folliculitis, a common yet less frequently identified disorder. Symptoms often wax and wane depending on the patient’s activities, time of the year, current treatment regimens, and other factors. Pityrosporum Folliculitis will often worsen with traditional acne therapy and dramatically respond to antifungal therapy.
Thomas L Dawson - One of the best experts on this subject based on the ideXlab platform.
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skin diseases associated with malassezia species
Journal of The American Academy of Dermatology, 2004Co-Authors: Aditya K Gupta, Roma Batra, Robyn Bluhm, Teun Boekhout, Thomas L DawsonAbstract:Abstract 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.