Clinico-epidermiological studies on tinea versicolor

Introduction

Tinea versicolor is a cutaneous, superficial fungal infection characterized by pigmentary changes in the skin due to colonization of stratum corneum by a dimorphic fungus in the normal flora of the skin known as Malassezia furfur.[1] It is more common in young males and more prevalent in tropical region due to the relative high temperature and humidity.[2] Present study deals with the clinical and epidemiological features of tinea versicolor.

Materials and Methods

One hundred and twenty patients with tinea versicolor who attended the out-patient department of Dermatology in KMC Hospital, Attavar, Mangalore were inducted into the study. A detailed history regarding the age, sex, occupation, climate, family history, personal habits and course of the disease was taken. A clinical examination was done noting the distribution of the lesions, colour of the lesions, presence of scales and associated seborrhoeic dermatitis of the scalp. Each case was confirmed by scraping and Woods lamp. All the patients were given appropriate treatment.

Results and Observations

Out of the 120 patients examined, 88 (73.30%) were males and 32 (26.60%) were females. Age of the patients ranged between 266 years. 30% of the patients belonged to the age group 21-30 which was the commonest age group involved. 42 patients (35%) first observed the white patches during summer, 22 (18.30%) during winter and 20 (16.60%) during rainy season. 26 (21.60%) patients also claimed that the problem was aggravated during summer. 42 patients (35%) were students, followed by manual labourers (20 in number) who constituted 16.60% of patients. [Table - 1]

118 (98.30%) patients got the disease in spite of regular bath. 20 (16.60%) patients were using talcum powder and 12 (10%) shampoos. Synthetic clothing were worn by 36 (30%) patients. 26 (21.60%) patients shared the bath rooms. 16 (13.30%) gave history of sharing the beds and 4 (3.30%) were sharing the clothes. 82 (68.30%) never gave a history of any mode of contact. A positive family history was obtained only in 46 (38.30%) patients. Out of them 12 (10%) gave a history in spouses and 16 (13.30%) in parents. [Table - 2]

The disease was seen commonly on the neck (71.60%), back (70%) and chest (58.30%). It was asymptomatic in 70% and mild itching was present in the rest. 22(18.30%) patients suffered from some systemic diseases like malignancy, tuberculosis or diabetes. 16 (13.30%) patients gave a history of taking immunosuppressive drugs for their systemic problems.

The disease was continuous without taking any treatment in 88 (73.30%) patients and continuous in spite of taking treatment in 26 (21.60%). In 2 (1.60%), it recurred after the treatment. It subdided without treatment and then recurred in 4 (3.30%).

Morphologically 90 (75%) patients showed hypopigmented variety and 10 (8.30%) showed hyperpigmented variety. 20 (16.60%) patients were of mixed variety. Macular pattern was observed in 104 (86.60%) patients, follicular in 8 (6.60%), confluent in 12 (10%) and guttate in 2(1.60%). Scaling was seen in 90 (75%) and was absent in 30 (25%). Co-existing scalp seborrhoeic dermatitis was seen in only 14 (11.60%) patients.

Scraping was done in all patients in whom scales were available.56 (46.60%) patients showed positive result under KOH examination. Woods lamp was done in all and 94 (78.30%) patients gave a positive fluorescence under Woods lamp.

Discussion

Tinea versicolor is commonly seen in young adults. Higher incidence in males than in females has been reported by many authors.[2],[3] Childhood tinea versicolor in our study (3.30%) is rare as in other studies.[2],[3] where it ranges between 1-5%. The disease was first observed during summer in 35% of patients. Increased sweating during summer probably makes the person more susceptible for infection. Occlusion from talcum powder and synthetic clothing result in increased carbon dioxide concentration, altered microflora and altered pH.[4] Personal hygiene does not contribute to the spread of the disease because majority of our patients are from student population who take bath regularly.

A positive family history was obtained in 38.3% of the patients. Among the family members, spread from parents to children was more (13.30%) compared to spread among spouses (10%) indicating the role of a hereditary factor in the transmission of the disease.[2],[4]

In our study the disease was seen in association with systemic diseases like malignancy, tuberculosis or diabetes. The disease flares up when the immunity goes down.

Clinically the lesions were seen mostly on the neck, back and chest. Localisation of the lesions reflected the distribution of the sebaceous glands. Morphologically 75% of the patients showed hypopigmentation which was similar to the previous studies. Lipoperoxidation process produced by the pityrosporum accounts for the clinical hypopigmented appearance.[4] Our study showed hyperpigmented macules in 8.30% of the patients. Proposed theory for this is the increased thickness of the keratin layer and more pronounced inflammatory cell infiltrate in these individuals acting as a stimulus for the melanocytes.

Co-existing seborrhoeic dermatitis of the scalp was seen in 11.60% in our study. Pityrosporum ovale found in patients with dandruff has some antigenic similarities with Pityrosporurn orbiculare and one can be transformed into another form.[4]

Recurrence rate of tinea versicolor is very high.[2],[4] Even though the yeast is a part of normal flora, sometimes it resides deep in the hair follicles. This may contribute to the high recurrence rate. Unless the predisposing factors are removed after the completion of the treatment, the recurrences cannot be prevented.