Onychomycosis is the most prevalent nail disease and accounts for approximately 50 percent of all onychopathies.1
In developing countries, higher priorities in socioeconomic concerns and health issues for other diseases, have resulted in low awareness of onychomycosis by physicians and the general public alike. In spite of improved personal hygiene and living environment, onychomycosis continues to spread and persist. Though there is a clearly diseased appearance associated with this condition, onychomycosis is all too often regarded as merely a cosmetic problem of relatively minor importance that is hardly worth the effort to seek treatment in many cases.
Although onychomycosis is rarely life threatening, its high incidence and prevalence and the associated morbidity makes it an important public health problem.2
6.2 Review of Literature :
The term onychomycosis is derived from the Greek word “onyx”, a nail and “mykes” a fungus.
Onychomycosis affects 5% of the population worldwide and represents about 30% of mycotic cutaneous infections.
Reports concerning the prevalence of onychomycosis are conflicting with estimates ranging from 2-3% to 13% in the western population. In Southeast Asia the prevalence of onychomycosis is relatively low. Lower in tropical countries (3.8%) than in subtropical countries and the countries in the temperate zone (18%).2 In Delhi, the prevalence of onychomycosis has been estimated to be 45%.3
The prevalence rate of onychomycosis is determined by age, predisposing factor, social class, occupation, climate, living environment and frequency of travel.
The prevalence is higher (25%) in patients with human immunodeficiency virus infection (HIV). Several studies have shown that prevalence of onychomycosis increases with age, reasons for which may include poor peripheral circulation, diabetes, repeated nail trauma, longer exposure to pathogenic fungi, sub optimal immune function, inactivity or the inability to cut the toe nails or maintain good foot care. The prevalence of dystrophic nail changes and onychomycosis is increased among hemodialysis patients.4 As is the case among adults, prevalence rates for onychomycosis among children are quite variable : a recent review of studies of the subject in several countries lists prevalence rates varying from 0% (United states, Wales and Finland) to 2.6% (Guatemala).2 In the study conducted in Indonesia showed highest incidence of onychomycosis in the age group 25 -45/50 years and female to male ratio-1.5:1 to 2:1.5
In a study in the United Kingdom the results in the population surveyed revealed a prevalence of dermatophyte nail infection of 2.8% in men and 2.6% in women. In the group aged 16-34 years, the prevalence rate was 1.3%; this increased to 2.4% in the group aged 35-50 years, and to 4.7% in those aged 55 years or over. 6
Onychomycosis and tinea pedis have long been recognized to be more common in certain occupational groups such as members of the armed forces and miners, where the humid microenvironment of protective boots and wet conditions, combined with enhanced opportunity for transmission in shared bathing facilities, presumably contribute to the problem.7
Residence in the urban areas appears to be associated with a higher prevalence of onychomycosis. The reasons for this observation are likely to be complex, as ‘urbanization’ may be associated with so many potential predisposing factors for fungal diseases, such as overcrowding, communal bathing areas, and clothing habits, in addition to ethnic, geographical and climatic differences between communities. It is a maximum, however, that tinea pedis follows in the footsteps of shoe-wearing populations, and the widespread adoption of occlusive footwear may be the most likely reason for increasing prevalence of onychomycosis in urban areas in developing countries.7
Nail changes in onychomycosis can occur in various form –onychodystrophy, subungal hyperkeratosis, onycholysis, discolouration (melanonychia or leuchonychia), or thickening of nail plate.8
Toenails are about 25 times more likely than fingernails to be infected. The longest toe, either the first or the second which bears the brunt of pressure and trauma from footwear, is particularly susceptible to invasion, although multiple nails are typically infected.1
The four clinical types of onychomycosis are
Distal subungual onychomycosis, (Most common type)
Proximal subungal onychomycosis(PSO)
White superficial onychomycosis (WSO)
There are three groups of fungi associated with onychomycosis : dermatophytes, non-dermatophytic moulds and yeasts.
Common fungal agents associated with onychomycosis9 : Dermatophytes (50%)
Trichophyton rubrun – 24%
Trichophyton mentagrophytes var. interdigitale – 16%
Trichophyton mentagrophytes var. mentagrophytes 4%
Epidermaphyton floccosum 3.2%
Non dermatophyte fungi
Aspergillus Niger (1.6%)
Aspergillus flavus (1.6%)
Candida albicans – 27.5%
1.5-6% of onychomycosis are caused by molds10
Mycological examination by direct microscopy (KOH preparation) combined with culture remains the gold standard technique, for its reasonable cost and least inconvenience to the patient.8
Nail plate biopsy with periodic acid Schiff (PAS) staining is the most sensitive method for the diagnosis of onychomycosis.11
Antifungal drug resistance may be one of cause of treatment failure. So fungal culture and sensitivity testing is performed to provide information to allow clinician to select appropriate antifungal agent useful for treating a particular fungal agent.
6.3 Objectives of the study:
1) To know the epidemiological profiles – incidence, age, sex, social and occupational distribution of onychomycosis.
2) Diagnosis of onychomycosis based on varied clinical presentation and investigations-KOH,culture,culture and sensitivity and nail plate biopsy with periodic acid schiff staining.
Materials And Methods:
7.1 Source Of Data:
A minimum of 50 patients with nail changes – onychodystrophy, onycholysis, subungal hyperkeratosis, discolouration of the nail plate. melanonychia or leuconychia and thickening of the nail plate constitute the source of data for a period of 2 years from November 2010 – October 2012 from Department of Dermatology Venereology and Leprosy, Chigateri General Hospital and Bapuji Hospital attached to J.J.M Medical College, Davangere.
7.2 Method Of Collection Of Data :( Including Sampling Procedure If Any)
A minimum of 50 cases of onychomycosis will be included in the study after informed consent and ethical clearance presenting to the department of dermatology.
Detailed history with duration and progression of lesion, complete dermatological examination along with general physical examination will be carried out according to the pre structured proforma.
All clinical types of onychomycosis irrespective of age and sex and immune status with above mentioned nail changes.
Exclusion Criteria: Individuals with known psoriasis, lichen planus, or other nail dystrophies.
Patients who have used any topical application, or have taken antibiotic in past 4 weeks.
The first step of the sample collection process is through cleansing of the nail area with alcohol to remove contaminants.
For distal subungual onychomycosis, the abnormal nail is clipped proximally and the nail bed and underside of the nail plate are scraped with a 1-2 mm serrated curette : the outermost debris should be discarded.
For proximal subungual onychomycosis, the normal surface of the nail plate is pared down with a no. 15 surgical blade at the lunula and the white debris is collected with a sharp curette from the deeper portion of the plate and the proximal nail bed.
White superficial onychomycosis, the white spots on the nail are scraped and the outermost surface is discarded; the while debris directly underneath is then collected.
For candida infection, the material closest to the proximal and lateral nail edges should be obtained.
The sampled material can be divided into two portions : one for direct microscopy and the remainder for culture. Material sent to the microbiology lab of J.J.M Medical college in sterile black packet.
Samples are subject to
Direct microscopy using 20% KOH
Culture : sample is inoculated on to Sabouraud’s dextrose agar (SDA) and kept at 250c for 10-14 days.
Identification done based on colony characteristics, tease mount, lactophenol cotton blue preparation and slide culture techniques.
Antifungal susceptibility is then performed using agar dilution method.
Nail plate fragments are sent in a 10% buffered formalin container for histopathologic analysis such as periodic acid schiff (PAS) staining.
7.3 Does the study require any investigations or interventions to be conducted on patients or other humans or animals? If so, please describe briefly:
Kaur R, Kashyap B, Bhalla P. A five year survey of onychomycosis in New Delhi, India : Epidemiological and laboratory aspects. Indian JD 2007;52(1):39-42.
Kuvandik G, Meryemcetin, Genctoy G, Horoz M, Duru M, Akcali C et al. The prevalence, epidemiology and risk factors for onychomycosis in hemodialysis patients. BMC Infectious Disease 2007;7:102.
Bramono K, Budimulija U. Epidemiology of onychomycosis in Indonesia : Data obtained from three individual studies. Jpn J Med Mycol 2005;46:171-176.
Roberts DT. Prevalence of dermatophyte onychomycosis in the United Kingdom : Results of an omnibus survey. Br J Dermatol 1992;126(39):23-7.
Williams HC. The epidemiology of onychomycosis in Britain. Br J D 1993;129:101-109.
Das NK, Ghosh P, Das S, Bhattacharya S, Dutta RN, Sengupta SR. A study on the etiological agents and clinico-mycological correlation of finger nail-oriychomycosis in Eastern India. Int JD 2008;53(2):75-9.
Aghamirian MR, Ghiasian SA. Onychomycosis in Iran : Epidemiology, causative agents and clinical features. Jpn J Med Mycol 2010;41:23-29.
Andre J, Achtan G. Onychomycosis. IJD 1987 Oct.;26(8):481-490.
Weinberg JM, Koestenblatt EK, Tutrone WD, Tishler ER, Najarian L. Comparison of diagnostic methods in the evaluation of onychomycosis. JAAD 2003 Aug.;49(2):193-197.