Tinea versicolor

A Clinical and Epidemiological Study of Pityriasis Versicolor in Baghdad City

BACKGROUND: Pityriasis versicolor (PV) is a common and chronic superficial mycosis seen in all age groups and characterized by dyspigmented lesions caused by dimorphic lipophilic yeast. AIM: The aim of the study was to study the clinical aspects, prevalence, and demographic data of patients with PV in Baghdad City. MATERIALS AND METHODS: Total of 175 patients with PV attending the department of Dermatology at Al Imamein Al Kadhemein Medical City and Alkarama Teaching Hospital in Baghdad city from January 2019 to January 2020 were included in this study. Diagnosis was done clinically. Interviews with patients were done using a questionnaire designed by the researcher. RESULTS: From 175 patients with PV, there were 71 (40.6%) males and 104 (59.4%) females. The mean age was 23.97 ± 10.25 years. The majority of cases 71 (40.6%) were 21–30 years. Eighty-one (46.3%) patients were presented from April to June. Itching presented in 21.7% of patients. The majority of patients (48.6%) presented with hyperpigmented type. Neck was the most common site to be involved in 101 patients (57.7%). CONCLUSION: The most common age group affected was 21–30 years. Females were commonly affected. Peak incidence was observed in April–July months. Neck was the most common site affected. Hyperpigmented type is more commonly presented type.

Ketoconazole inhibits Malassezia furfur morphogenesis in vitro under filamentation optimized conditions

Malassezia furfur, a constituent of the normal human skin flora, is an etiological agent of pityriasis versicolor, which represents one of the most common human skin diseases. Under certain conditions, both exogenous and endogenous, the fungus can transition from a yeast form to a pathogenic mycelial form. To develop a standardized medium for reproducible production of the mycelial form of M. furfur to develop and optimize susceptibility testing for this pathogen, we examined and characterized variables, including kojic acid and glycine concentration, agar percentage, and pH, to generate a chemically defined minimal medium on which specific inoculums of M. furfur generated the most robust filamentation. Next, we examined the capacity of ketoconazole to inhibit the formation of M. furfur mycelial form. Both low and high, 0.01, 0.05 and 0.1 µg/ml concentrations of ketoconazole significantly inhibited filamentation at 11.9, 54.5 and 86.7%, respectively. Although ketoconazole can have a direct antifungal effect on both M. furfur yeast and mycelial cells, ketoconazole also has a dramatic impact on suppressing morphogenesis. Since mycelia typified the pathogenic form of Malassezia infection, the capacity of ketoconazole to block morphogenesis may represent an additional important effect of the antifungal.

Malassezia-Can it be Ignored?

Genus Malassezia comprises of 14 species of “yeast like fungi,” 13 of which are lipophilic and 1 is nonlipophilic. They are known commensals and in predisposed individuals they commonly cause a spectrum of chronic recurrent infections. They rarely also cause serious illnesses like catheter-related blood stream infections, CAPD associated peritonitis etc., Though these fungi have been known to man for over 150 years, their fastidious nature and cumbersome culture and speciation techniques have restricted research. Since the last taxonomic revision, seven new species have been added to this genus. Their ability to evade the host immune system and virulence has increased the spectrum of the diseases caused by them. These agents have been implicated as causal agents in common diseases like atopic dermatitis recently. Though culture-based research is difficult, the new molecular analysis techniques and facilities have increased research in this field such that we can devote more attention to this genus to study in detail, their characteristics and their growing implications implications in the clinical scenario.

Terbinafin 1% Cream and Ketoconazole 2% Cream in the Treatment of Pityriasis Versicolor: A randomized comparative clinical trial

OBJECTIVE

To make a comparison between terbinafine 1% cream and ketoconazole 2% cream in the treatment of pityriasis versicolor.

METHODS

This randomized single blind study included 110 patients with clinical diagnosis of pityriasis versicolor and positive mycological test for Malassezia furfur. The patients were randomly assigned to two groups. Group 1 used terbinafine cream and group 2 applied ketoconazole cream on the skin lesions for two weeks. Each group consisted of 55 patients. Clinical and mycological examinations were performed at baseline, at the end of the 2(nd), 4(th) and 8(th) week of starting the treatment regimens.

RESULTS

At the end of the 2(nd) week we achieved cure rates of 72% and 64.3% for group 1 and group 2 respectively. At the end of the 4(th) week the respective cure rates for group 1 and group 2 were 81.2% and 69%, and at the end of the 8(th) week 70.8% of the patients in group 1 and 61.9% of the patients in group 2 were cured.

CONCLUSION

The results of this study showed no significant statistical differences between the two groups in regard to cure and recurrence rates. But the numbers of cured patients were higher and recurrent cases were lower in group 1.

Cutaneous manifestations of infection in returning travelers

Dermatologic problems are common in returning travelers who seek medical care. Some common illnesses such as cellulitis or abscesses occur in travelers but are not unique to this patient group. Additionally, dermatologic illnesses not due to infection such as drug eruptions or phototoxicity are seen. Skin manifestations occur in many tropical illnesses such as dengue, schistosomiasis, and leishmaniasis. This article reviews the common causes of cutaneous illnesses associated with travel including non-infectious causes, infections that are not limited to travelers, and infections that are almost exclusively seen in travelers.

Skin Characteristics in Patients with Pityriasis Versicolor Using Non-Invasive Method, MPA5

Background

Skin pigmentary changes of pityriasis versicolor may occur as either hyperpigmented or hypopigmented lesions, depending on the outcome of interactions between Malassezia yeasts and the skin, such as lipoperoxidation process, stimulus of inflammatory cell to melanocytes, and increased thickness of keratin layer.

Objective

To investigate skin characteristic factors that enhance the susceptibility to Malassezia yeasts and provoke different color changes of pityriasis versicolor patients.

Methods

To clarify these factors, we investigated the skin characteristics of pityriasis versicolor patients, using a non-invasive method known as MPA 5® (Courage and Khazaka, Germany). A total of 90 normal healthy subjects and 30 pityriasis versicolor patients were included in this study.

Results

Both hyperpigmented and hypopigmented pityriasis versicolor skin lesions showed higher humidity, increased sebum excretion rate and increased transepidermal water loss (TEWL) values than normal healthy subjects. But no significant difference of specific Malassezia yeasts species between hyperpigmented and hypopigmented skin lesions was evident.

Conclusion

These results indicate that higher humidity and increased sebum level provide a better growing environment of Malassezia yeasts in the skin, leading to the assumption that interaction between Malassezia yeasts and skin barrier materials makes disruption of skin barrier causing increased TEWL.

Malassezia yeast species isolated from Iranian patients with pityriasis versicolor in a prospective study

The goal of this study was to determine the prevalence of Malassezia species in pityriasis versicolor lesions and to examine if the range of species varies with patients characteristics such as: age, sex and family history and also clinical findings such as site and number of the lesions. In a prospective study from July 2006 to July 2007, the patients with a clinical diagnosis of pityriasis versicolor (n = 166) were asked to participate in the study. A total of 116 patients had positive culture for Malassezia species: M. globosa was found in 52 (31.3%) cases, M. furfur in 34 (20.5%) cases, M. pachydermatis in 12 (7.2%) cases, M. restricta in 12 (7.2%) cases, M. slooffiae in 6 (3.6%) cases. According to our data, M. globosa is the main species causing pityriasis versicolor, M. furfur was found to be the second-most frequent species. M. sympodialis and M. obtusa were not found in any case, and in 30.2% of patient's Malassezia culture was negative.

Identification of Malassezia species from pityriasis versicolor in Indonesia and its relationship with clinical characteristics

Pityriasis versicolor (PV) is a chronic superficial fungal disease caused by Malassezia spp. The incidence is as high as 30-40% in tropical climates. Previous studies indicate that the geographic factor has influence on the main species isolated from PV. Our aim was to identify Malassezia spp. from PV patients in Indonesia and their correlation to clinical characteristics. Isolates of Malassezia were collected from 98 PV patients (62 males and 36 females). Identification was based on morphological observation and biochemical evaluation. Leeming Notman agar was used as isolation culture medium. The biochemical evaluation consisted of specimen culture onto Sabouraud dextrose agar, Cremophor EL, Esculin, Dixon's agar at 37 degrees C and catalase reaction. The isolates found were Malasseziafurfur (42.9%), M. sympodialis (27.5%), M. globosa (13.3%), M. slooffiae (7.7%), M. obtusa (7.7%) and M. restricta (2.2%), and 7.14% specimens were unidentified. There was no statistically significant association between Malassezia spp. and demographic characteristics and clinical characteristics of the patients. Unlike reports from temperate climate countries, this study in Indonesia found M. furfur as the most frequently isolated Malassezia spp. in PV patients.

The genetic epidemiology of tinea versicolor in China

To study the clinical and epidemiological profile of Pityriasis versicolor (PV) and to determine the possible genetic model for PV in Chinese Han, we investigated 503 patients with PV who were recruited by a questionnaire method. Statistical analysis, heritability and complex segregation analysis were performed using EPI INFO 6.0, SPSS 10.0, the Falconer method and the SAGE-REGTL programs. In the total 503 PV patients, the mean age of onset was 22.85 +/- 10.36 years. For male and female patients, the peak ages of initial onset were both 20-29 years. A total of 106 (21.1%) patients were reported to have a positive family history of PV. The mean age of onset in males with positive family history was earlier than those with negative family history (t = 3.58, P < 0.01). Higher rate of recurrence and longer duration were seen in the patients with positive family history than those with negative family history. The heritability of PV in first-, second- and third-degree relatives was 48.13%, 40.11% and 27.20% respectively. Based on the REGTL results, the best model was a polygenic additive model for PV.

[Malassezia yeasts and their significance in dermatology]

Yeasts of the genus Malassezia belong to the normal microflora of the human skin. In addition they are known to cause a variety of skin diseases; the most frequent of which is pityriasis versicolor. Malassezia yeasts are also thought to be associated with seborrheic dermatitis, dandruff and Malassezia folliculitis. Recently the significance of Malassezia yeasts as a trigger factor for atopic dermatitis of the head and neck region has been pointed out. The role of the Malassezia yeasts in these different diseases has been controversial in the past and remains an issue because of difficulties in isolation, culture and differentiation of the organism. Thanks to molecular techniques, 10 species can actually be differentiated. The article presents the different Malassezia-associated diseases, their clinical picture, diagnosis and appropriate therapy. In addition the speciation of Malassezia is reviewed.

Malassezin, a novel agonist of the aryl hydrocarbon receptor from the yeast Malassezia furfur, induces apoptosis in primary human melanocytes

Pityriasis versicolor is the most common skin mycosis in humans worldwide. Yeasts of the genus Malassezia, particularly M. furfur, a saprophyte occurring widely on human skin, are generally regarded as the causative agents. Pityriasis versicolor is often accompanied by a long-lasting depigmentation that persists even after successful antimycotic therapy. M. furfur is able to convert tryptophan into a variety of indole alkaloids, some of them showing biological properties that correlate well with certain clinical features of pityriasis versicolor. This suggests a possible role for these compounds in the depigmentation process. We now report that human melanocytes undergo apoptosis when exposed to the crude mixture of tryptophan metabolites from M. furfur. The active compound was identified as malassezin, previously isolated by us from the same source and characterized as an agonist of the aryl hydrocarbon (Ah) receptor. The compound could, therefore, contribute to the marked depigmentation observed during the course of pityriasis versicolor.

Pityriarubins, Novel Highly Selective Inhibitors of Respiratory Burst from Cultures of the Yeast Malassezia furfur: Comparison with the Bisindolylmaleimide Arcyriarubin A

Pityriasis versicolor is the most common skin mycosis in humans worldwide. Yeasts of the genus Malassezia, particularly M. furfur, a saprophyte occurring widely on human skin, are generally regarded as the causative agents. M. furfur is able to convert tryptophan into a variety of indole alkaloids, some of them showing biological properties that correlate well with certain clinical features of pityriasis versicolor. This suggests a possible role for these compounds in the pathophysiology of the disease. We here report that the novel pityriarubins A, B and C, isolated from cultures of the yeast, inhibit respiratory burst in human neutrophils, activated by various agents, in a highly selective, unexpected manner. The release of 5-lipoxygenase products after challenge of neutrophils with the calcium ionophore A23187 is also inhibited in a dose-dependent manner. These activities reflect the close structural relationship of pityriarubins to bisindolylmaleimides, which have recently gained great interest as protein kinase inhibitors.

Fehlendes granulozytares Infiltrat bei der Pityriasis versicolor - ein Hinweis fur eine spezifische antiinflammatorische Aktivitat des Erregers? Missing granulocytic infiltrate in pityriasis versicolor - indication of specific anti-inflammatory activity of the pathogen?

The yeast Malassezia furfur is a part of the resident flora of human skin. It causes various diseases such as pityriasis versicolor, which hardly shows signs of inflammation despite marked clinical symptoms (e.g. hypopigmentation). The pathophysiology related morphological picture might give a clue to this phenomenon. As a part of the literature data are controversial, the present study compared the inflammatory infiltrate of pityriasis versicolor with that of tinea corporis in 40 human skin preparations each from diagnostic specimens. All preparations were stained with HE and PAS. Neutrophilic granulocytes were counted in the HE stain, and hyphae and spores in the PAS stain. The number of counted cells was related to the size of the respective area and the values were compared between pityriasis and tinea corporis. Significantly, more neutrophilic granulocytes were found with tinea corporis (P > 0.01), while they were virtually not demonstrable with pityriasis versicolor. It is surprising that fungal load in the stratum corneum is significantly higher with pityriasis versicolor (P > 0.01). Obviously the immune response involving neutrophilic granulocytes does not occur despite high bacterial load. This might be explained by reduced immunogenicity because of high content of lipids in the cell membrane. Furthermore, pityriarubins that are produced during tryptophan metabolism might be involved, which, in a stimulus-dependent manner, can suppress the ROS production of neutrophilic granulocytes in vivo.

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.

Superficial fungal infections

Superficial fungal infections arise from a pathogen that is restricted to the stratum corneum, with little or no tissue reaction. In this Seminar, three types of infection will be covered: tinea versicolor, piedra, and tinea nigra. Tinea versicolor is common worldwide and is caused by Malassezia spp, which are human saprophytes that sometimes switch from yeast to pathogenic mycelial form. Malassezia furfur, Malassezia globosa, and Malassezia sympodialis are most closely linked to tinea versicolor. White and black piedra are both common in tropical regions of the world; white piedra is also endemic in temperate climates. Black piedra is caused by Piedraia hortae; white piedra is due to pathogenic species of the Trichosporon genus. Tinea nigra is also common in tropical areas and has been confused with melanoma.

Study of the distribution of Malassezia species in patients with pityriasis versicolor and healthy individuals in Tehran, Iran

Background

Pityriasis versicolor is a superficial infection of the stratum corneum which caused by a group of yeasts formerly named pityrosporium. The taxonomy of these lipophilic yeasts has recently been modified and includes seven species referred as Malassezia. The aim of this study is to compare the distribution of Malassezia species isolated from pityriasis versicolor lesions and those isolated from healthy skins.

Methods

Differentiation of all malassezia species performed using morphological features and physiological test including catalase reaction, Tween assimilation test and splitting of esculin.

Results

In pityriasis versicolor lesions, the most frequently isolated species was M. globosa (53.3%), followed by M. furfur (25.3%), M. sympodialis(9.3%), M. obtusa (8.1%) and M. slooffiae (4.0%). The most frequently isolated species in the skin of healthy individuals were M. globosa, M. sympodialis, M. furfur, M. sloofiae and M. restricta which respectively made up 41.7%, 25.0%, 23.3%, 6.7% and 3.3% of the isolated species.

Conclusions

According to our data, M. globosa was the most prevalent species in the skin of healthy individuals which recovered only in the yeast form. However, the Mycelial form of M. globosa was isolated as the dominant species from pityriasis versicolor lesions. Therefore, the role of predisposing factors in the conversion of this yeast to mycelium and its subsequent involvement in pityriasis versicolor pathogenicity should be considered.

Isolation of Malassezia globosa and M. sympodialis from patients with pityriasis versicolor in Spain

Pityriasis versicolor is a superficial infection of the stratum corneum by several yeast species formerly collectively named Malasseziafurfur. The genus Malassezia has been recently enlarged with new species. With the exception of M. pachydermatis, the remaining six species have an absolute requirement in vitro for supplementation of long-chain fatty acids in media. These lipophilic yeasts comprise six species: M. furfur, M. globosa, M. obtusa, M. restricta, M. slooffiae and M. sympodialis. The aim of this study was to establish whether there was any association between the various species of Malassezia and pityriasis versicolor lesions. Thus, we studied the isolates from 79 patients with pityriasis versicolor, both from lesions and from apparently healthy skin close to the visible lesions. In pityriasis versicolor lesions, the species most frequently isolated was M. globosa (90%), followed by M. sympodialis (41%). Almost all isolates (99%) belonged to one of these two species. The most frequent pattern was M. globosa as the sole species (58% of cases), although the association with M. sympodialis was also frequent (30%). These results confirmed M. globosa as the main agent of pityriasis versicolor and M. sympodialis as the second agent in importance. Malassezia globosa was found to be a species with high levels of esterase and lipase enzymes of probable importance in their pathogenicity.

Pitiríase Versicolor

A expressão pitiríase versicolor define uma infecção fúngica superficial caracterizada por alterações na pigmentação cutânea. O distúrbio de pigmentação é devido à colonização do estrato córneo por um fungo dimórfico, lipofílico, encontrado na flora normal da pele, conhecido como Malassezia furfur. Trata-se de doença prevalente nos trópicos, mas também comum em climas temperados. Há vários tratamentos disponíveis com taxas elevadas de cura, porém as recorrências são freqüentes.

Comparison of a single 400 mg dose versus a 7-day 200 mg daily dose of itraconazole in the treatment of tinea versicolor

BACKGROUND

Tinea (pityriasis) versicolor is a superficial infection of the stratum corneum by the lipophilic fungus known as Malassezia furfur.

OBJECTIVE

To evaluate the efficacy and safety of a 400 mg single dose or 7-day 200 mg daily dose of itraconazole capsules in the treatment of mycologically confirmed pityriasis versicolor.

METHODS

A total of 50 patients were entered into a randomized, open, clinical trial comparing a 400 mg single dose (n = 24 for group 1) with a 7-day 200 mg daily dose (n = 26 for group 2) of itraconazole. Clinical signs and symptoms and mycologic evaluation (potassium hydroxide preparation and Wood's lamp) were performed before treatment, and at weeks 3 and 6 after treatment.

RESULTS

Both regimens of itraconazole were effective. Our results showed that there were no significant differences in efficacy and safety between the two treatment regimens (chi-square tests, p > 0.05).

CONCLUSIONS

On the basis of these findings, a single dose of itraconazole 400 mg/day was as effective as the 7-day 200 mg daily dose in the treatment of pityriasis versicolor.

Epidemiology of Malassezia yeasts associated with pityriasis versicolor in Ontario, Canada

The genus Malassezia was recently revised to include seven species, but the clinical significance of each of these species is not clearly understood. To obtain a better understanding of the contribution of individual Malassezia species to the epidemiology of pityriasis (tinea) versicolor, we used Leeming-Notman medium to culture patient skin specimens showing positive evidence of Malassezia infection in direct microscopy. Isolates were identified on the basis of recently published morphological and physiological tests for distinction of the new species. Identification using recently developed molecular criteria was also carried out for the ambiguous cases. Malassezia species were cultured from 111 cases of pityriasis versicolor in the Canadian province of Ontario. The most frequently isolated species were Malassezia sympodialis, M. globosa and M. furfur which respectively made up 59.4%, 25.2% and 10.8% of the isolated etiological agents. M. globosa was commonly isolated from a small number of pityriasis versicolor specimens obtained from investigators outside Canada. A large number of additional Ontario specimens with positive direct microscopy failed to yield a culture; however, it is suggested that this is consistent with the standard sampling practice of scraping the older portions of pityriasis lesions rather than the margins, where viable fungal cells are most likely to occur.