Introduction

Onychomycosis, fungal infection of the nail, is a common medical problem of adults that can cause an important adverse impact on the quality of the affected individual's life, leading to reduced self-esteem and possibly affecting work potential.^1,2 It is an infection usually caused by dermatophytes, yeast, and non-dermatophytic moulds.³

Recently, it has been reported that about 20% of persons between 40 and 60 years of age have onychomycosis, and it represents around 30% of all superficial mycotic infection and 50% of nail disorders.^1,3,4 Frequent exposure to fungus, damage by trauma or disease, irrational use of antibiotics, HIV infection and immunosuppressive drug therapy are some predisposing factors for onychomycosis.¹

The importance of the study of onychomycosis lies in the increase of its prevalence. In the United States of America, it is estimated at between 2% and 13% present onychomycosis, again the more elderly individuals presenting this infection in a percentile that varies from 15% to 20% and can reach as much as 50%.² This study aimed to evaluate the prevalence and to identify the predominant pathogens of onychomycosis among a population of Garbage Collectors.

Materials and Methods

Participants (Garbage Collectors)

Specimen Collection and Processing

Statistical Analyses

Results

Of the 80 garbage collectors examined, 45 were male (Age mean: 23.8; Median: 23.0; Range: 62) and 35 female (Age mean: 19.7; Median: 15.0; Range: 63). Among examined individuals, 24 (30%) presented nails with abnormal aspects, of these 15 were male and 9 were female. Mycological exam confirmed Onychomycosis in all 24 specimens collected. About clinical types of onychomycosis was observed: 15 (62.5%) with Distal and lateral subungual onychomycosis; 01 (4.2%) with White superficial onychomycosis; 05 (20.8%) with Proximal subungual infection and 03 (12.5%) with Total dystrophic onychomycosis (date not show).

Table 1 shows the results of laboratory analysis. Presented positive direct exam 20 collected samples (25% of the total individuals, 83.3% of the ungual abnormality and 82.6 of the positive culture). The culture was positive in 23 samples (28.75% of the total individuals, 95.8% of the ungual abnormality and 100% of the positive direct exam). Only 1 sample was positive direct exam and negative culture.

Figure 1

Table 1. Direct Microscopy versus Culture

The prevalence of onychomycosis and the etiologic agent between different age groups was not statistically significant p=0.384 and p=0.293, respectively.

Figure 1 shows the etiologic agents isolated by culture between genders. The etiologic prevalence of onychomycosis was: 12 (50%) Trichophyton rubrum, 08 (33.3%) Candida spp., 03 (12.5%) Trichosporon beigelii. The etiologic agent was not identified in 01 (4.17%) sample. The onychomycosis etiology was not different statistically between gender (p=0.661).

Figure 2

Figure 1. Etiologic Agent of Onychomycosis between genders.

Discussion and conclusion

In the present study, onychomycosis was found to be commonest among garbage collectors. This population work collecting garbage to recycle without any protection equipments, they have a poor socioeconomic status and live around the landfill.

Onychomycosis is the most common nail disease in adults. In various studies the prevalence ranged from 2.7% to 13%.⁶ Recently the prevalence of onychomycosis in North America has been estimated to be from 6.8% to 13.4%.⁷ Many studies point that the onychomycosis prevalence increase with advancing age, due to a reduced rate of nail growth and increased trauma of nails compared to the younger age group, thereby providing the fungal organism with more opportunity to cause nail bed disease and nail plate invasion.^2,6 Unlike our study, the prevalence of onychomycosis between different age groups was not statistically significant (p=0.384).

The onychomycosis was found in 24 (30%) of examined individuals. Our results are similar to other studies from Brazil, Spain, Tunis and Colombia.^2,6,8,9,10 About clinical types of onychomycosis was observed: 15 (62.5%) with Distal and lateral subungual onychomycosis; 01 (4.2%) with White superficial onychomycosis; 05 (20.8%) with Proximal subungual infection and 03 (12.5%) with Total dystrophic onychomycosis. These findings are accorded to Araujo and colleagues (2003).²

We observed similar results between direct exam (NaOH) and culture, also found in others studies.¹¹ Of a 24 specimens collected, 20 were positive by direct exam and 23 by culture. Only 1 sample was positive by direct exam and negative by culture (Table 1). A study in Rio de Janeiro showed NaOH positive with positive culture in 219 cases and NaOH positive with negative culture in 346 cases.² Brilhante and colleagues (2005)³ didn’t find good accordance between direct exam and culture.

The etiologic prevalence of onychomycosis was: 12 (50%) Trichophyton rubrum, 08 (33.3%) Candida spp., 03 (12.5%) Trichosporon beigelii (Figure 1). The etiologic agent was not identified in 01 (4.17%) sample. The onychomycosis etiology was not different statistically between gender (p=0.661). Araujo and colleagues (2003)² examined patients with presumption of onychomycosis and found in toenails dermatophytes (64.7%), Candida spp (30.1%) and non-dermatophytes and others (5.2%), when examined fingernails found dermatophytes (5.6%), Candida spp (88.8%) and non-dermatophytes and others (5.6%). Godoy and colleagues (2009)⁶ revealed the yeasts as the most frequent agents in fingernail onychomycosis (38.3%) and C. albicans 18.3%, C. parapsilosis 13.8% were the most frequent species. The dermatophytes did have a major role in fungal infection of toenails onychomycosis (31.6%).The authors suggest that the higher proportion could be the result of more traumas and the greater use of occlusive footwear in male and tight fitting shoes with high heels in females. Trichophyton rubrum in 33.2% followed by T. mentagrophytes in 6.3% were the most frequent species in toenail onychomycosis. The non-dermatophytic fungi were etiologic agent in 7.4% of cases. A similar result was found in different states of Brasil.^11,12,13

In conclusion, this study demonstrated the high prevalence of onychomycosis among garbage collectors what could be best evaluated for health public departments. The mains agents causing onychomycosis in this population was T. rubrum, Candida spp and T. beigelii.