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Year : 2016 | Volume
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| Issue : 2 | Page : 159-165 |
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Clinicomycological profile of pityriasis versicolor in Assam |
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Ajanta Sharma1, Debajit Rabha2, Saveta Choraria3, Debeeka Hazarika4, Giasuddin Ahmed5, Naba Kumar Hazarika2
1 Department of Microbiology, Assam Medical College, Dibrugarh, West Bengal, India 2 Department of Microbiology, Gauhati Medical College, Guwahati, Assam, India 3 Department of Microbiology, Ramkrishna Seva Prathisthan, Kolkata, West Bengal, India 4 Department of Dermatology, Venereology and Leprology, Gauhati Medical College, Guwahati, Assam, India 5 Department of Biotechnology, Gauhati University, Guwahati, Assam, India
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Date of Web Publication | 9-May-2016 |
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Abstract | | |
Background: Geographical variation in the distribution of Malassezia species associated with pityriasis versicolor (PV) has led to the necessity of studying epidemiological, mycological, and clinical characteristics of PV. Aims: To study the epidemiological, mycological, and clinical characteristics of PV in a tertiary care hospital. Settings and Design: The study was carried out with a cross-sectional design. Materials and Methods: Two hundred and sixty-two consecutive PV patients were subjected to detailed history, clinical examination, and investigations. Skin scrapings were processed by direct microscopy and culture. Isolates were identified by phenotypic characteristics and polymerase chain reaction-restriction fragment length polymorphism. Association of Malassezia species with clinical and epidemiological characteristics was studied. Statistical analysis of the data was done using statistical software. Results: Maximum number of PV cases (33.9%) belonged to the age group of 21–30 years with a male preponderance. 61.4% of the patients had a sedentary lifestyle, 70.2% showed the gradual onset of the disease, 51.1% presented with pruritus and in 66.4% of the patients symptoms were continuous. Most commonly involved body site was neck (27.8%), 77.09% of the lesions were bilaterally asymmetrical, 87.4% were macular, and 89.3% were hypopigmented. Malassezia furfur (77.3%) was the predominant species. Sedentary lifestyle (61.4%) and increased sweating (48%) were the most commonly associated predisposing factors. Conclusion: PV is more common in males. Distribution of Malassezia species varies significantly from those reported in other parts of India. M. furfur was the most common species responsible for PV in our region. Hence, further studies are required to evaluate the exact cause of this variation. Keywords: Assam, epidemiology, Malassezia, pityriasis versicolor
How to cite this article: Sharma A, Rabha D, Choraria S, Hazarika D, Ahmed G, Hazarika NK. Clinicomycological profile of pityriasis versicolor in Assam. Indian J Pathol Microbiol 2016;59:159-65 |
How to cite this URL: Sharma A, Rabha D, Choraria S, Hazarika D, Ahmed G, Hazarika NK. Clinicomycological profile of pityriasis versicolor in Assam. Indian J Pathol Microbiol [serial online] 2016 [cited 2019 Dec 16];59:159-65. Available from: http://www.ijpmonline.org/text.asp?2016/59/2/159/182027 |
Introduction | |  |
Pityriasis versicolor (PV) is one of the common disorders of pigmentation seen in tropical and subtropical regions which is characterized by cutaneous pigmentary changes due to the colonization of the stratum corneum by a lipophilic fungus known as Malassezia.[1] PV is mainly characterized by the appearance of macules and finely scaled plaques with colors ranging from white (the alba or achromians variant) to pink, salmon, or brown. Recently, a red variant (PV rubra) has been described.[2]
Eichstedt described this yeast-like fungus belonging to genus Malassezia about 150 years ago as the causative agent of PV and to date, this is the only human disease in which these yeasts have been firmly established as pathogens.[3] Guého et al. reclassified it into seven distinct species namely Malassezia furfur, Malassezia pachydermatis, Malassezia sympodialis, Malassezia globosa, Malassezia obtusa, Malassezia restricta, and Malassezia slooffiae and currently this has been expanded to include Malassezia dermatis, Malassezia japonica, Malassezia nana, Malassezia yamayoensis, Malassezia caprae, Malassezia equine, and Malassezia cuniculi.[4],[5]
Malassezia is an endogenous saprophyte which under appropriate conditions converts from saprophytic yeast to predominantly parasitic mycelial form.[6] Factors responsible for this transition include warm, humid environment, heredity, Cushing's disease, immunosuppression, and malnutrition.[7] Genetic factors seem to have a role since the disease is more common among first-degree family members.[8]
PV is one of the most common dermatomycosis and is prevalent in regions with warm, humid climate, where up to 40% of the population may be affected.[9] Prevalence of PV varies according to geographical region with variation in the distribution of Malassezia species.[10],[11] Hence, the aim of this research was to determine the prevalent Malassezia species associated with PV in Assam and to study the epidemiological and clinical profile of the PV cases.
Materials and Methods | |  |
A hospital-based study with a cross-sectional design was carried out at in a Tertiary Health Care Hospital in Assam. The study was carried out for 2 years and 262 consecutive clinically diagnosed cases of PV of all ages and genders attending dermatology outpatient department were included in the study after taking approval from the Institutional Ethics Committee and informed written consent from the patients. The inclusion criteria for the cases were macule with or without erythema characterized by branny scaling, patchy lesion with varying changes of skin color [Figure 1]a and [Figure 1]b. Patients presenting with hypopigmentary disorders of skin other than PV and patients who were on antifungal therapy (systemic and topical) were excluded from the study. Various demographic variables like age and sex, clinical profile-like seasonal variation, duration of illness, the age of onset, type of onset, presence or absence of pruritus, continuity of the symptoms, body sites involved, various characteristics of the lesions, and distribution of various Malassezia species were studied. | Figure 1: (a) Hypopigmented macule of pityriasis versicolor (b) hyperpigmented lesion of pityriasis versicolor
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Under aseptic precautions, skin samples were collected using 1 square inch scotch tape from the sites showing good fluorescence under wood's lamp, as well as from the nonlesional sites. Direct microscopy was done using Parker's stain and Calcofluor white stain (Becton, Dickinson and Company, Sparks, USA), to detect “Spaghetti and Meatballs” appearance of the fungus [Figure 2]. Samples were inoculated into Leeming-Notman agar and incubated at 32°C for 7 days in a humid chamber. All the colonies from the lesional and nonlesional sites were counted and compared. Phenotypic characterization was done by studying the colony characteristics, microscopic morphology, detection of enzyme activity (catalase, urease and ß-glucosidase activity on esculin agar), Tween and Cremophor EL assimilation (Sigma-Aldrich Co, St Louis, USA), glycine assimilation, and growth at 37°C and 40°C [12] [Table 1]. | Figure 2: “Spaghetti and Meatball” appearance of Malassezia in the skin (Parker's stain, ×400)
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 | Table 1: Scheme used for phenotypic characterisation of Malassezia species isolated in the study[14]
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Glass bead phenol-chloroform method was used to extract Malassezia DNA as described by Yamada et al.[13] Molecular characterization was done by polymerase chain reaction-restriction fragment length polymorphism (RFLP) by following the protocol of Giusiano et al.[14]M. furfur Centraalbureau Schimmelcultures (CBS) 1878, M. globosa CBS 7886, M. japonica CBS 9432, M. restricta CBS 7877, M. sympodialis CBS 7222, M. slooffiae CBS 7956, M. yamatoensis CBS 9725, and M. pachydermatis CBS 1879 were used as reference strains of CBS, The Netherlands and the strains were obtained from the National Culture Collection of Pathogenic Fungi, Postgraduate Institute of Medical Education and Research, Chandigarh, India. Primers were selected to amplify target part of 26SrDNA of Malassezia species. Amplification was performed using forward primer: 5'-TAACAAGGATTCCCCTAGTA-3' and reverse primer: 5'-ATTACGCCAGCATCCTAAG-3' (Promega Corporation, Madison, USA). Amplified DNA products (size 580 bp) were further subjected to RFLP using CfoI and MboI (Promega Corporation, Madison, USA) because CfoI alone cannot differentiate between M. sympodialis and M. dermatis[15],[16] [Figure 3]a and [Figure 3]b. For selection of the enzymes we used CLC Sequence Viewer (version 5.0, CLC Bio., Free Software) for analysis of different restriction enzymes for the highly conserved 26SrDNA sequences of known Malassezia species obtained from GenBank accession numbers AY743602, AJ249951, AJ249954, AJ249953, AJ249950, AY743606, AJ249952, AB070365, AB105862, AJ305330, AY743616, and GU733708. | Figure 3: Polymerase chain reaction-restriction fragment length polymorphism of 26SrDNA region. (a) MboI; Lane 1: Malassezia furfur Centraalbureau Schimmelcultures 1878 (440 bp); Lane 2: Malassezia globosa Centraalbureau Schimmelcultures 7966 (515 bp); Lane 3: Malassezia japonica Centraalbureau Schimmelcultures 9432 (580 bp); Lane 4: 100 bp DNA ladder; Lane 5: Malassezia restricta Centraalbureau Schimmelcultures 7877 (580 bp); Lane 6: Malassezia slooffiae Centraalbureau Schimmelcultures 7956 (580 bp); Lane 7: Malassezia sympodialis Centraalbureau Schimmelcultures 7222 (438 bp).(b) CfoI; Lane 1: Malassezia furfur Centraalbureau Schimmelcultures 1878 (206, 113, 250bp); Lane 2: Malassezia globosa Centraalbureau Schimmelcultures 7966 (454, 120 bp); Lane 3: Malassezia japonica Centraalbureau Schimmelcultures 9432 (106, 174, 202, 250 bp); Lane 4: 100 bp DNA ladder; Lane 5: Malassezia restricta Centraalbureau Schimmelcultures 7877 (580 bp); Lane 6: Malassezia slooffiae Centraalbureau Schimmelcultures 7956 (106, 250 bp); and Lane 7: Malassezia sympodialis Centraalbureau Schimmelcultures 7222 (203, 356 bp)
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Detailed history and clinical profiles were recorded in a predesigned proforma. Presence or absence of predisposing factors was also recorded. Chi-square test was done to find out the statistical significance of the association between various variables. The data were analyzed using Statistical Package for Social Science Software (SPSS version 12.3, Inc., Chicago, IL, USA).
Results | |  |
The age of the PV patients ranged from <1 year to 70 years (median: 29.37 ± 13.55 years). The study population consisted of 172 males (median: 30.99 ± 13.65 years) and 90 females (median: 25.76 ± 12.82 years). The age distribution of the PV cases is shown in [Table 2]. PV was found to be more prevalent (33.9%) in the age group of 21–30 years. PV was significantly more common in male than female in the age groups 31–40 and 51–60 years (P < 0.05). No significant sex variation was observed in the other age groups.
Clinical profiles of the PV cases are shown in [Table 3]. Prevalence of PV was seen slightly increased in the summer and monsoon season as evidenced by 59.1% of the cases presenting in these seasons, 40.8% did not show any seasonal variation.
Duration of illness was <1 month in 39 (14.8%) cases, 1–12 months in 145 (55.3%) cases, and 1–20 years in the remaining 78 (29.7%) cases. Age of onset was found to be postpubertal in 88.9% of the cases, pubertal in 8.4%, and 2.6% in prepubertal cases. In 70.2% of the cases onset was gradual, 29.7% presented with sudden onset; pruritus was an associated complaint in 51.1% cases. 66.4% of the patients had continuous symptoms and in 33.5% of the cases symptoms were intermittent.
27.8% of the PV cases presented with a lesion in the neck, 17.5% in the back, 16% in the chest, 12.2% in the face, 11.4% in the upper limb, and 8.7% in the trunk. The least affected sites were lower limb (5.3%) and flexural areas (0.76%) [Table 3].
The most common pattern of distribution of the lesions was bilaterally asymmetrical (77.09%), followed by bilaterally symmetrical (14.5%), and unilateral (8.4%). 87.4% of the patients presented with macule, 67.9% of which were having well-defined border, 78.6% of them were scaly, 85.9% had white scales, and 14.07% had brown scales. 9.5% of the cases presented with patch and 3.05% of the cases had mixed (both macule and patch) type of lesions [Table 3]. Regarding pigmentation, 89.3% of the PV cases presented with hypopigmented lesions, followed in frequency by a hyperpigmented lesion in 5.7% of the cases and 4.9% of the cases with mixed types (both hypopigmented and hyperpigmented) [Table 3]. The statistical significance of association of body sites and demographic profile is shown in [Table 4]. Involvement of face was more common in children and adult males than adult females (P value 0.000 and 0.026 respectively). No significant association was found in the case of the other body sites.
M. furfur (77.3%) was the most prevalent species in the lesional sites followed by M. globosa (12.4%). M. furfur was also found as a predominant isolate from the nonlesional sites also, but the number of colonies was less than that from the lesional sites. The association of various Malassezia species with clinical profiles is shown in [Table 5]. No significant association was found between clinical profile and various Malassezia species.
38.6% cases were involved in manual labor while rest (61.4%) led a sedentary lifestyle. Students, children, homemakers with minimal outdoor activity, office workers, and business person were considered to have a sedentary lifestyle. Thirty-seven percent of the patients gave a history of the application of oil on the body surface, increased sweating was present in 48% cases, poor hygiene in 20.6%, malnutrition in 3.8% of the cases, and 20.6% of the cases were found to be on systemic steroid therapy. 14.9% of the PV cases had associated immunosuppressive disorders mostly diabetes mellitus and 16.8% of the patients gave a positive family history of PV [Figure 4].
Discussion | |  |
A number of facts revealed by our study were in conformity with those of previous studies while some were different and can be justified to draw attention for further studies. In this study, PV was found to be most common in young adults (age group 21–30). This was an expected outcome considering the high level of physical activity, increased sebaceous activity with the production of sebum at its peak in this age, and lipophilic nature of the causative fungus. The same predilection for age was reported in an African study.[17] PV is seen in adults and teenagers; however, it may be seen in children too. 10.7% of PV cases were found in the age group of 0–14 years in this study. It is rarely seen in older adults as found in this study, as well as reported in other studies also.[15] PV is significantly common in male than female in the age group 11–20 years and 31–40 years (P < 0.05). Patients in the age group 11–20 years were mostly students and hence are more conscious of their lesions. Most of our patients came from a lower socioeconomic group where drop out from the school is very common among females. Moreover, in the age group 31–40, the males are more involved in the outdoor activities and hence they are more exposed to increased environmental temperature and humidity.
Male to female ratio was equal (1:1) in 0–14 age group. But in older patients, males far outnumbered females (189 vs. 105; 1.8:1). Similar male preponderance was reported by earlier workers.[16] This can be explained by the fact that, males are more involved in outdoor activities which place them at high risk of exposure to factors like high temperature and humidity. On contrary to the other reports, the face was more commonly involved in males than females in this study.[9]
In Assam, during summer and monsoon, the environmental temperature and relative humidity rises in the state (above 37°C and >80% respectively). This leads to increased sweating which predisposes to PV. The seasonal trend was found in our study as most of the cases (59.1%) presented during the period of June to September. In the study of Dutta et al., maximum number of the cases presented during the period July to September and Rao et al. also reported clustering of cases (35%) during the summer months.[18],[19]
Common sites of involvement were face, chest, back, and neck in children; neck, back, and chest in both adult male and female above the age of 14 years in order of decreasing frequency. In an Indian study, PV was found to be distributed predominantly over the neck (71.6%), chest (58.3%), and back (70%). The involvement of flexural areas was uncommon. Distribution of lesions on various sites depends on the density of the sebaceous gland. As reported by earlier workers like Terragni et al. and Bouassida et al., the involvement of face was more common in the pediatric population in this study also.[20],[21] On contrary to the other studies, the involvement of face was significantly more common in males than females.[21] Involvement of face is rare in a temperate climate, which is mainly seen in children; but it is quite common in the tropical and subtropical region.[9]
The predominance of hypopigmented lesions in this study correlates with previous reports.[22] Hypopigmentation induced by this fungus may be due to the production of dicarboxylic acids by the fungus, the main component of which is azelaic acid. This acid acts through competitive inhibition of dihydroxyphenylalanine tyrosinase and perhaps has a direct cytotoxic effect on hyperactive melanocytes. Pathogenesis of hyperpigmentation is also not fully understood, but it may be due to increased thickness of the keratin layer and more pronounced inflammatory cell infiltrate in these individuals act as a stimulus for the melanocytes.[23]
M. furfur (77.3%) was the predominant isolate in our study followed by M. globosa (12.4%) which is the most predominant isolate found to be associated with PV as reported from other part of India and also from other countries as well [18],[24],[25],[26],[27],[28],[29] [Table 6]. This variation can be explained by the fact that M. furfur produces an indole alkaloid pityriacitrin which has the ability to protect this fungus against ultraviolet exposure and renders M. furfur more resistant to sun exposure.[30] | Table 6: Comparison of various variables between the present study and other studies
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Conclusion | |  |
The overall clinicomycological profile of PV infection in Assam as observed in this study differs significantly with many other studies in the distribution of Malassezia species suggesting the role of geographical, ethnic, or racial variation in causing PV and hence implies the necessity of further study for better understanding of its epidemiology. It is also necessary to evaluate the pathogenic potential of M. fufur as an etiological agent of PV.
Acknowledgment
I gratefully acknowledge the Department of Biotechnology, Ministry of Science and Technology, Government of India for their financial support in this work under Research and Development project grant vide sanction no: BT/PR3633/MED/29/330/2011 dated 26/03/2011.
I express my gratitude to Dr. Arunaloke Chakrabarti, Professor and Head, Dr. M.R. Shivaprakash, Additional Professor, Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh for providing the reference strains. I also gratefully acknowledge Mrs. Anjanamoyee Saikia, Lecturer Statistics, Department of Community Medicine, Gauhati Medical College, Guwahati, Assam, India and Shiva Saikia, Senior Research Fellow, Assam Medical College, Dibrugarh, Assam, India for their help in statistical analysis of data.
Financial support and sponsorship
Department of Biotechnology, Government of India.
Conflicts of interest
There are no conflicts of interest.
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Correspondence Address: Ajanta Sharma Department of Microbiology, Assam Medical College, Dibrugarh - 786 002, Assam India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/0377-4929.182027

[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6] |
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