A Mycological Study of Dermatophytoses in Thane

Mycological studies were done on 300 consecutive clinically diagnosed cases of dermatophytosis during the period 2001-2002, in Thane (Maharashtra). 213 samples (71.0%) were culture positive; while 205 (68.34%) were KOH positive. The most common isolate was Tinea rubrum (53.52%), followed by Tinea corporis (20.19%). A predominance of female patients was observed.

Introduction

Dermatophytosis is defined as “fungal infection of the keratinized tissue of the hair, nail and stratum corneum of the skin”.¹ The disease is caused by fungi belonging to genera Trichophyton, Minosporum and Epidermatophyton.² The fungal infections of the skin and its appendages are more common in tropical countries like India due to environmental factors like heat and humidity. The risk factors include socio-economic conditions like overcrowding, poverty and poor personal hygiene.³ The type and frequency of dermatophytoses may change with time, due to changes in living standards and application of preventive measures like personal hygiene.⁴

Superficial fungal infections are usually diagnosed clinically. The identification of the fungal species is epidemiologically important since the source of infection can be traced and its transmission halted.

Thane is located to the north of Mumbai metropolis, on the West Coast of Maharashtra State. The altitude varies from 8-11 metres above mean sea level. The relative humidity fluctuates between 60% and 70% for most part of the year and the area receives heavy rainfall. Thus, the environmental conditions are conducive for development of superficial mycoses.

This study was conducted in order to identify - (a) the clinical pattern of various dermatophytoses, and (b) the most common fungal pathogen.

Material and Methods

The present study was conducted on 300 consecutive clinically diagnosed patients with dermatophytoses who attended a tertiary care hospital in Thane, Maharashtra during the two-year period: January 2001 to December 2002.

The history recorded on the proforma included - age, sex, occupation, duration of infection, site of infection and family history of the disease. Clinical findings covered the number of the lesions, presence of scaling/pustules/scarring and morphology of hair.

The skin scrapings were obtained by scraping the lesions with a scalpel. A portion of the skin scrapings was taken on a grease-free slide for microscopy. 10% KOH was used for the detection of hyphae and spores in skin scrapings. In case of hair samples, this was used for detecting ectothrix and endothrix.

The second portion of skin scrapings was inoculated, using a scalpel and loop, on Sabouraud’s agar with Chloramphenicol and Cycloheximide at pH 5.5 and incubated at room temperature (28° ± 1° Celsius) for 3 weeks. The obverse and reverse of the slide mounts were observed daily for growth, morphology, colour, colony texture, pigmentation,

and structure of the spores. If no growth was observed at the end of 3 weeks, the culture was labelled as “negative”.²
Nail clippings were kept in 10% KOH (Potassium hydroxide) solution for 10-18 hours and observed under microscope.

Results

Out of 300 patients (187 females and 113 males) who were subjected to mycological studies, nearly one-third (32.67%) of patients belonged to the age group of 21-40 years. The difference between the age-sex distribution of males and females was statistically significant at p < 0.005 (Table 1).

213 (71.0%) were culture positive; while 205 (68.34%) were KOH positive (Table 2). Tinea corporis (20.19%), followed by Tinea capitis (19.72%) were the frequent clinical presentations. The common sites of Tinea corporis infection were the abdominal skin (on the “saree” or “dhoti” line), back and neck. Trichophyton rubrum was isolated from more than half (53.52%) of the patients (Table 3).

Discussion

In the present study, most of the patients (58.67%) were in the economically active age group at 21-40 years, which is vulnerable to fungal infections due to increased environmental exposure.⁵ The age group of 21-30 years is predominantly affected, according to other researchers (Table 4).^6-8

The male-to-female ratio was 0.6:1. However, other researchers^5-6 have reported a higher frequency of dermatophytoses among males (Table 4). The preponderance of females in the present study may be attributed to a variety of reasons -

1. Higher exposure of females to humid or wet environment at home (especially in the kitchen), which is favourable for development of fungal infections.

2. Adult females use more clothing than their male counterparts even in hot and humid weather due to social reasons. Women usually wear sarees, which are tied tightly around that waist. Sweating is more among those involved in manual labour.

3. Likelihood of males seeking treatment elsewhere.

Hormonal changes in the females have also been implicated in the genesis of dermatophytoses.²

The variations in KOH positivity in several studies^5-6 have been outlined in Tables 2 and 4.

Tinea corporis was the most frequent clinical presentation (20.19%) while Tinea manum was the least frequent (9.39%) (Table 3). Similar findings have been reported in other studies.^6-8

Tinea rubrum was the most common isolate (53.52%) in this study (Table 2). T. rubrum affects the horny layer of the skin and hence it is more common.² The frequency of T. rubrum isolates in other studies were - 28.12%,⁶ 59.76%,⁷ and 88.15%.⁵

Candida albicans was isolated in 3.75% of patients, mainly women (Table 2). Similar findings have been made by Huda et al.⁵ This may be because women are generally engaged in wet work.

Conclusion

The present study was conducted in Thane which has a hot and humid climate for most of the year and the area receives heavy rainfall during the monsoon. Thus, the environmental conditions are conducive for development of superficial mycoses.

Medical interventions are useful in attending to patients at the individual level. But, due to socio-economic conditions like overcrowding, poverty and poor personal hygiene the superficial mycoses may contribute to spread in hot and humid areas. Thus, there is an urgent need for public education campaigns and socio-economic interventions at the community level, to overcome the risk factors like overcrowding and lack of personal hygiene.

References

1. Cheesborough M. District Laboratory Practice in Tropical Countries - Part 2:. Cambridge University Press, UK 2000;235-48.

2. Rippon JW. Medical Mycology. 3rd edition. WB Saunders, Philadelphia, USA. 1988;140-248.

3. Mahapatra LN. Study of Medical Mycology in India - An Overview. Indian Journal of Medical Research 1989;89:351-53.

4. Mehrotra HK, Bajaj AK, Gupta SC, Mehrotra TN, Atal PR, Agarwal AK. A study of dermatophytes at Allahabad. Indian Journal of Pathology and Microbiology 1978;131-39.

5. Huda NN, Chakraborty N, Sharma JN, Bordolol. A clinico-mycological study of superficial mycosis in upper assam. Indian Journal of Dermatology, Venerology and Leprology 1995; 61 : 329-32.

6. Patwardhan N, Dave R. Dermatophytosis in and around Aurangabad. Indian Journal of Pathology and Microbiology 1999;42 (4) : 455-62.

7. Chowdhary A, Deshmukh AB, Bansal MP, Deshpande AD. Study of Dermatophytoses at Aurangabad. Indian Journal of Medical Microbiology 1986; 32 : 229-32. Cited in reference no. 6.

8. Damle AS, Fule RD, Kaundianya DV, Patoria NK, Agarkar RY, Bagle RT. Mycology of Cutaneous Fungal Infections in Ambajogai - a Rural area”. Indian Journal of Dermatology, Venereology and Leprology 1986; 45 : 266-68. Cited in reference no. 6

USE OF MOBILE PHONES IN ICU-WHY NOT BAN?

Due to the rapid growth of mobile telecommunications it is predicted that by 2005 there will be 1.6 billion mobile phone users worldwide. The usage of cellaphones in Intensive Care Units carries with it a high incidence of interference with a number of medical devices like implantable defibrillators, cardioverters, pacemakers, monitors and other important devices like ventilators. The do’s and don’ts need to be seriously considered in the Intensive Care set up, in particular. It does demand a lot of self discipline on the part of professionals working in such a set up and more appropriate measure however appears to be a ban on the usage of cell phones in the Intensive Care set up, a step already taken in other countries like United States, United Kingdom and therefore perhaps due in our context too.

ME Yeolekar, A Sharma, JAPI, 2004; 52 : 311-12.

*Associate Professor; **Professor and Head; ***Senior Technician, Department of Microbiology, #Professor and Head, Department of Preventive and Social Medicine, Rajiv Gandhi Medical College, Kalwa, Thane 400 605.