Risk factors associated with onychomycosis

Dermatitis among farmers engaged in peri-urban aquatic food production in Hanoi, Vietnam

OBJECTIVE

To assess whether exposure to wastewater is a risk factor for dermatitis (eczema) among farmers engaged in peri-urban aquatic food production in Hanoi, Vietnam.

METHODS

A cross-sectional study with two follow-ups was conducted from April to December 2005 in two peri-urban communes in Hanoi, one using wastewater and another using river, rain and well water for aquatic food production. In each commune, 100 households were randomly selected and adult household members engaged in farming field work were interviewed in three surveys. Farmers who reported skin problems at the time of interviews were examined and treated by a dermatologist. Data were analysed for one farmer per household.

RESULTS

The overall prevalence of dermatitis from 592 interviews was 6.3%. The commune which used wastewater had a much higher overall prevalence of dermatitis (10.4%) than the commune that did not (2.1%; P-value < 0.001). Multivariable logistic regression analyses showed that occupational wastewater contact was an important risk factor for dermatitis (odds ratio [OR] 3.0; 95% confidence interval [CI] 1.1-7.7). Duration of daily wastewater contact was not significantly associated with dermatitis. Aquaculture work in the wet season carried an increased risk of dermatitis in both communes (OR 2.8; 95% CI 1.02-7.6). The use of personal protective measures during field work and washing hands and feet after work did not reduce the risk for dermatitis. However, observations showed that these practices were applied in such a way that they were unlikely to provide effective protection against wastewater contact.

CONCLUSION

Contact with wastewater is an important risk factor for dermatitis among farmers engaged in wastewater-fed peri-urban aquatic food production. Additional studies should test preventive and mitigating measures such as improved personal protection and hygiene.

Emerging therapeutic agents for onychomycosis

Onychomycosis is a frequent disorder that represents the most prevalent fungal infection, particularly among older individuals. Diverse fungi of the dermatophyte, non-dermatophyte mold and yeast families have been reported to be responsible for onychomycosis. The output from the pharmaceutical industry of new antifungals to treat onychomycosis has been limited over the last decade. Present treatment options include both oral and topical drugs, with oral therapies giving better outcomes. However, neither of these treatment options provides high cure rates that are durable. At present, azoles and allylamines are keeping the pivotal roles. New derivatives with a favorable risk-benefit ratio and new formulations of older azoles seem to be promising. Thus, ongoing drug development activities have focused on novel delivery technologies to facilitate incorporation of existing antifungal drugs inside the nail plate and the discovery of new active antifungals.

The prevalance, epidemiology and risk factors for onychomycosis in hemodialysis patients

BACKGROUND

Onychomycosis has a high prevalance among immunocompromised patients such as diabetics and hemodialysis patients. In the present study, we aimed to investigate the prevalence of onychomycosis among hemodialysis patients with and without diabetes mellitus, and to find out the factors likely to be associated with the development of onychomycosis among hemodialysis patients.

METHODS

One hundred and nine hemodialysis patients were enrolled. Fifty-seven of hemodialysis patients had the diagnosis of diabetes mellitus. Nail scrapings were obtained from 76 patients who had dystrophic nail changes. Samples were examined with 20% potassium hydroxide solution and all of the samples were inoculated on Saboraud's dextrose agar, potateus dextrose agar and mycobiotic agar. Diagnosis of onychomycosis was based on the presence of both positive clinical signs and positive potassium hydroxide test.

RESULTS

Onychomycosis was diagnosed in 26.6% of hemodialysis patients. Diabetes mellitus was present in 68.9% of patients with onychomycosis. Toenail scraping cultures were reported to be positive in 19.7% of patients with dystrophic nail changes. Logistic regression analysis revealed that the presence of diabetes mellitus and the mean duration of hemodialysis were the significant predictors associated with the development of onychomycosis.

CONCLUSION

The prevalence of dystrophic nail changes and onychomycosis is increased among hemodialysis patients. The dialysis duration and the presence of diabetes mellitus are the independent risk factors associated with the development of onychomycosis in uraemic patients.

Infección micótica plantar e interdigital en pacientes con onicomicosis

In patients with onychomycosis (OM) 71.5% of them have been reported with plantar fungal infection. The aim of this study was to study the frequency and distribution of plantar and interdigital affection in diabetic patients and in a control group without diabetes, all of them with OM. Diabetic patients with OM were more frequently diagnosed with plantar (61.2%) than interdigital (46.7%) infection. In the control group similar results were obtained; patients with OM in 76.5% had plantar mycotic infection and 67.1% interdigital involvement.

Distribution of toenail dystrophy predicts histologic diagnosis of onychomycosis

BACKGROUND

Onychomycosis (OM) affects up to 10% of the general population and is associated with functional impairment. Clinically, OM can mimic nail psoriasis, trauma, lichen planus, oncyhogryphosis, and other disorders. Laboratory methods for diagnosing OM vary in accuracy and predictive value. Clinical clues to OM would help guide laboratory testing and decrease improper empiric antifungal therapy.

OBJECTIVE

The goal of this study was to determine whether particular distribution patterns of toenail dystrophy are associated with fungal infection of the nail.

METHODS

We retrospectively reviewed toenail clippings submitted over a 5-year period to our pathology department for periodic acid-Schiff (PAS) staining for diagnosis of OM.

RESULTS

Specimens from a total of 311 patients (130 men, 181 women; mean age: 48.3 yrs; range: 19-97 yrs) were included. Overall, 150 specimens (48.2%) were histologically positive for OM. OM was significantly more likely to be diagnosed in men (P < .01), in persons over the age of 64 (P < .02), and in the context of tinea pedis (P < .001). Involvement of the third (41/65; 63.1%) or fifth (27/41; 65.9%) toenails of either foot significantly correlated with OM (P < .025). Dystrophy of the great toenail was seen in 257/311 (82.6%) and was associated with OM in about half of cases (128/257; 49.8%). Dystrophy of first and fifth nails on the same foot was predictive of OM (23/32; P < .01). Unilateral dystrophy correlated positively with OM (79/142; 55.6%; P < .02), with a stronger correlation when 2 or more nails were dystrophic (33/42; P < .001). Dystrophy of the second or fourth nails, a single nail, or all 10 nails did not support or contradict of OM. Female gender was a negative predictor for OM (P < .001).

LIMITATIONS

Potassium hydroxide and culture results were not available to correlate with histology. PAS staining of nail clippings has inherent diagnostic limitations.

CONCLUSIONS

Dystrophy of the third or fifth toenails, of the first and fifth nails on the same foot, unilateral dystrophy, male gender, an age over 64, and the presence of tinea pedis are all independent predictive factors of OM. Presence of these patterns of dystrophy may help to clinically distinguish OM and guide laboratory testing.

Toenail onychomycosis: current and future treatment options

Onychomycosis is a common disease affecting as much as 8% of the general population. Treatment of onychomycosis is challenging, complicated by low cure rates and relatively high relapse rates. This paper reviews the efficacy of current oral, topical, and surgical treatment options. Currently, the treatment of choice for toenail onychomycosis is oral terbinafine because of its high efficacy, low relapse rates, and cost-effectiveness. Oral itraconazole or fluconazole could be considered for infections caused by Candida. Topical therapies may be a useful adjunct to these systemic therapies, but are less effective when used alone. More research is needed to determine the best measures for preventing reinfection.

Onychomycosis in older patients

Onychomycosis represents the most frequent nail disorder. Its prevalence is influenced by gender, age and several comorbid diseases. Accurate diagnosis relies on laboratory examination, particularly nail histomycology. This method refers to the microscopic examination of histological sections prepared from nail clippings for the purpose of detecting the presence of invading fungi. The pathogens may belong to one or a combination of the groups of dermatophytes, yeasts or nondermatophyte molds. The choice of the diagnostic laboratory method influences the accuracy of the information. Histomycology is recognized to be the most sensitive and specific method. The prevalence of onychomycosis in the elderly population varies according to gender and the nature of the fungal pathogen. Epidemiological figures differ according to the nature of the reference population. In particular, it is of the utmost importance to establish the ratio between the raw numbers of onychomycoses and the total number of individuals in the same age group living in the same geographical area.

Diagnosing Onychomycosis

Onychomycosis is the most prevalent nail disease, representing nearly half of all clinically diagnosed onychopathies. Given the pervasive nature of the disease and that successful treatment depends on the proper identification of the causative organism,accurate and reliable methods of diagnosis are necessary. This article discusses the efficacy of the various methods used for the diagnosis of onychomycosis.

Onychomycosis: beyond cosmetic distress

Onychomycosis, or fungal infection of the nail, is the most common nail disease affecting children (although to a lesser extent) as well as adults. The distress it provokes is not only of a cosmetic kind; it may impair the quality of life. The different clinical types of onychomycosis should be differentiated from similar-looking nail diseases. As far as therapy is concerned, the appearance of new antifungal drugs in the 1990s makes our job easier, but it does not allow us to cure 100% of the patients. Relapses still exist. The aim of this article is to help dermatologists achieve a tailor-made treatment for their patients. The clinical type, the compulsory mycological investigations, the age of the patient, his medical history (drug intake), as well as the use of nail cosmetics, must be considered.

Epidemiological and aetiological study on tinea pedis and onychomycosis in Algeria

Epidemiological studies on tinea pedis and onychomycosis, common fungal infections, have been conducted in many parts of the world. There are currently no studies of tinea pedis and/or onychomycosis in Algeria. The aim of this paper was to study the epidemiology of foot diseases, including tinea pedis and onychomycosis and to identify the aetiological factors of these infections in outpatients attending the Department of Dermatology of the Central Hospital of Army in Algiers, Algeria. A total of 1300 male subjects, mean age 35.9 +/- 16 years (range: 16-80) were recruited during the period November 2003 to November 2004 and were clinically examined. A complete dermatological examination was performed on all subjects, and skin and nail specimens of the feet were taken from those patients presenting signs of tinea pedis and/or onychomycosis for microscopy and fungal culture. Clinical diagnosis for tinea pedis and onychomycosis was suspected in 249 and 72 subjects, respectively, and confirmed in 197 and 60 cases, respectively, by positive cultures, resulting in a global prevalence of tinea pedis and toenail onychomycosis of 15% and 4.6% respectively. The age groups most commonly infected were 50-59 and 20-29 years. The yeast species Candida parapsilosis and the dermatophytic species Trichophyton rubrum were shown to be the most common pathogens in both tinea pedis (C. parapsilosis 20.4%; T. rubrum 17%) and onychomycosis (T. rubrum 35%; C. parapsilosis 28.3%). This is the first investigation dealing with fungal foot diseases in Algeria. The clinical and epidemiological data collected would serve as reference for future research and may be useful in the development of preventive and educational strategies.

Onychomycosis: Recent Progress in the Epidemiology, Diagnosis and Treatment

Recent progress in the epidemiology, diagnosis and treatment of onychomycosis is summarized. The risk factors of this condition were investigated, and the results of analyses of the systemic state of patients, shape of nails, blood circulation around nails, nail growth rate and causative fungi were reported. In making a diagnosis of onychomycosis, the major effect of the quality of collected nail samples on the results was reconfirmed. In addition to the KOH method and culture method, a molecular biological method was introduced. From the therapeutic perspective, 1) prevention of recurrence, 2) identification of patients with high risk of onychomycosis, and 3) attempting new treatments (development of new drugs, improvement of administration and dosage, and evaluation of combined therapy) were discussed. The effectiveness of concomitant use with nail lacquer is anticipated in combined therapy. New studies on accurate diagnosis, early detection and early stage treatment are now being undertaken.

Epidemiology and clinical classification of onychomycosis

OBJECTIVES

To review recent data - what is new in the epidemiology of onychomycoses? To identify the most relevant diagnostic criteria for effective therapy.

METHODS

The preliminary results of the European Onychomycosis Observatory (EUROO) study were analysed. In this international study, physicians completed questionnaires concerning patient profile and the disease.

RESULTS

One of the most interesting novel findings was that sampling requests were often not made [only 3.4% of general physicians (GPs) and 39.6% of dermatologists]. This means that no information about causative agent(s) was available, hindering appropriate treatment choice. Furthermore, contrary to previous findings, 70.7% of participants did not practice sports. Lastly, these preliminary findings showed that treatment strategy depends largely on the type of treating physician, with GPs preferring monotherapy and dermatologists preferring combination therapy.

CONCLUSIONS

A consensus was reached that treatment strategy should depend on the severity of nail involvement and the causative fungus. It is thus important to promote the importance of sampling. To simplify the choice of an appropriate treatment, onychomycosis may be divided into just two clinical groups: onychomycosis with and without nail matrix area involvement. However, the distinct clinical findings (number and type of affected nails, multimorbidity, drug interaction, etc.) in each individual case must be taken into account to ensure an appropriate treatment decision.

Patients at risk of onychomycosis - risk factor identification and active prevention

OBJECTIVES

The aims of this workshop were to identify risk factors for onychomycosis and to reach consensus on the management of high-risk groups to allow the development of guidelines to help doctors recognize risk factors that complicate treatment.

RESULTS AND CONCLUSIONS

Previous Trichophyton rubrum infection, older age, abnormal nail morphology, immunodeficiency and genetic factors were identified as risk factors for initial infections. Risk factors for recurrence (relapse and re-infection) are largely the same. The experts agreed that the prevention of onychomycosis and its recurrence should be based on the correct treatment of tinea pedis, screening family members and adequate patient education. In addition, generic management recommendations for each high-risk group were discussed: * Immunosuppressed patients Usual dose and treatment length not appropriate Follow-up required Beware of drug interactions * Diabetics Prophylactic foot care combined with nail treatment Good opportunity for patient education, footwear, foot care, etc. Beware of drug interactions * Psoriatics and patients with abnormal nails Dermatophyte eradication does not restore normal nails * Children High failure rate possibly due to compliance problems.