Nondermatophyte Molds Research Articles

Infektionen an Finger- und Zehennägeln durch Pilze und Bakterien

Infections of the finger and the toe nails are most frequently caused by fungi, primarily dermatophytes. Causative agents of tinea unguium are mostly anthropophilic dermatophytes. Both in Germany, and worldwide, Trichophyton rubrum represents the main important causative agent of onychomycoses. Yeasts are isolated from fungal nail infections, both paronychia and onychomycosis far more often than generally expected. This can represent either saprophytic colonization as well as acute or chronic infection of the nail organ. The main yeasts causing nail infections are Candida parapsilosis, and Candida guilliermondii; Candida albicans is only in third place. Onychomycosis due to molds, or so called non-dermatophyte molds (NDM), are being increasingly detected. Molds as cause of an onychomycosis are considered as emerging pathogens. Fusarium species are the most common cause of NDM onychomycosis; however, rare molds like Onychocola canadensis may be found. Bacterial infections of the nails are caused by gram negative bacteria, usually Pseudomonas aeruginosa (recognizable because of green or black coloration of the nails) but also Klebsiella spp. and gram positive bacteria like Staphylococcus aureus. Treatment of onychomycosis includes application of topical antifungal agents (amorolfine, ciclopirox). If more than 50 % of the nail plate is affected or if more than three out of ten nails are affected by the fungal infection, oral treatment using terbinafine (in case of dermatophyte infection), fluconazole (for yeast infections), or alternatively itraconazole are recommended. Bacterial infections are treated topically with antiseptic agents (octenidine), and in some cases with topical antibiotics (nadifloxacin, gentamicin). Pseudomonas infections of the nail organ are treated by ciprofloxacin; other bacteria are treated according to the results of culture and sensitivity testing.

Mycology – an update. Part 1: Dermatomycoses: Causative agents, epidemiology and pathogenesis

Dermatomycoses are caused most commonly by dermatophytes. The anthropophilic dermatophyte Trichophyton rubrum is still the most frequent causative agent worldwide. Keratinolytic enzymes, e.g. hydrolases and keratinases, are important virulence factors of T.rubrum. Recently, the cysteine dioxygenase was found as new virulence factor. Predisposing host factors play a similarly important role for the development of dermatophytosis of the skin and nails. Chronic venous insufficiency, diabetes mellitus, disorders of cellular immunity, and genetic predisposition should be considered as risk factors for onychomycosis. A new alarming trend is the increasing number of cases of onychomycosis - mostly due to T.rubrum - in infancy. In Germany, tinea capitis is mostly caused by zoophilic dermatophytes, in particular Microsporum canis. New zoophilic fungi, primarily Trichophyton species of Arthroderma benhamiae, should be taken into differential diagnostic considerations of tinea capitis, tinea faciei, and tinea corporis. Source of infection are small household pets, particularly rodents, like guinea pigs. Anthropophilic dermatophytes may be introduced by families which immigrate from Africa or Asia to Europe. The anthropophilic dermatophytes T.violaceum, T.tonsurans (infections occurring in fighting sports clubs as "tinea gladiatorum capitis et corporis") and M.audouinii are causing outbreaks of small epidemics of tinea corporis and tinea capitis in kindergartens and schools. Superficial infections of the skin and mucous membranes due to yeasts are caused by Candida species. Also common are infections due to the lipophilic yeast fungus Malassezia. Today, within the genus Malassezia more than 10 different species are known. Malassezia globosa seems to play the crucial role in pityriasis versicolor. Molds (also designated non-dermatophyte molds, NDM) are increasingly found as causative agents in onychomycosis. Besides Scopulariopsis brevicaulis, several species of Fusarium and Aspergillus are found.

Onychomycosis in qassim region of saudi arabia: a clinicoaetiologic correlation.

Onychomycosis is mainly caused by dermatophytes, but yeasts and nondermatophyte molds have also been implicated, giving rise to diverse clinical presentations. The aetiological agents of the disease may show geographic variation. The aim of the present study was to isolate the causative pathogens and to correlate the various clinical patterns of onychomycosis with causative pathogens. The study population comprised 170 patients with clinical suspicion of onychomycosis. Nail samples were collected for direct microscopic examination and culture. Clinical patterns were noted and correlated with causative pathogens. Out of total 170 cases included in the study, 140 (82.4%) were positive by microscopy and 77 (45.3%) showed positive mycological findings by both microscopy and culture. The male: female ratio was 1:2.5 and the mean age was 35.29 ± 16.47 years. Fingernails were involved in 51.9%, toenails in 28.6% and both fingernails and toenails in 19.5% of the 77 patients. The clinical types noted were distal lateral subungual onychomycosis (71.4%), proximal subungual onychomycosis (10.4%), total dystrophic onychomycosis (10.4%), superficial white onychomycosis (3.9%) and mixed pattern onychomycosis (3.9%). Yeasts were the most common pathogens isolated, being found in 36 patients (46.8%) followed by nondermatophyte molds which were isolated from 28 patients (36.4%) followed by dermatophytes which were isolated from 13 patients (16.9%). Distal lateral subungual onychomycosis was the most common clinical presentation. Candida albicans, Aspergillus species and Tricophyton rubrum were the major pathogens. A single pathogen can give rise to more than one clinical type.

Onychomycosis: Sampling, diagnosing as efficiant part of hospital pharmacology

Introduction Onychomycosis is a fungal infection of one or more nails. Causes of onychomycosis are dermatophytes, yeasts and non-dermatophyte molds, but the most common cause is Trichophytonrubrum (T. Rubrum) from the group of dermatophyte fungi. The aims Using sampling determination of the most common clinical type of onychomycosis, lokalization and involvement of the nail plate, and monitoring the efficacy of methods/tests in the diagnosis of nail onychomycosis. Material and methods This paper is a part of academic IV phase study. The study included 30 patients with onychomycosis. Each sample was seeded on Sabouraud Dextrose Agar (SDA) and Diluted SDA (D-SDA) at 28°C and 37°C, as well as the Dermatophyte Test Medium (DTM) at 28°C. Identification of isolated fungi to the level of genus/species has been based on macroscopic and microscopic characteristics by KOH and Blancophor fluorescent dye. PCR were performed to detect T. Rubrum-specific and pan-dermatophyte multiplex PCR product. Informed consent was obtained from all patients. Results The most common clinical form was subungual lateral distal onychomycosis (DLSO)of the hands and feet pollex fingernails, while the size of the involvement of the nail plate was 1/2 - 1/3 in the majority of patients. Cultivation gave a positive result in 50% of cases and the most commonly isolated microorganism was the T. Rubrum. For negative cultures (50%) the PCR was carried out which demonstrated high sensitivity and T. Rubrum remained the most frequently detected. Conclusions Using the methods of cultivation and PCR, onychomycosis was confirmed in 28 (93.3%) patients. Cultivation gave a negative result in 50% of cases, while the PCR was positive in 86.6%. Our research shows the highest incidence of T. Rubrum (60%). In continuation of this study will be analyzed the choice and effectiveness of therapy.

Non‐dermatophyte mould onychomycosis: a clinical and epidemiological study at a dermatology referral centre in Bogota, Colombia

Worldwide prevalence of non-dermatophyte mould onychomycosis has increased in recent years; however, available information on the topic is confusing and oftentimes contradictory, probably due to the small number of reported cases. The aim of this study was to determine and describe the aetiological agents, as well as the epidemiological and clinical characteristics of non-dermatophyte mould onychomycosis in a dermatology referral centre in Bogota, Colombia. A cross-sectional descriptive study was conducted between January 2001 and December 2011 among patients who attend the National Institute of Dermatology with a confirmed diagnosis of onychomycosis by non-dermatophytes moulds. There were 317 confirmed cases of non-dermatophyte mould onychomycosis in 196 women and 121 men whose average age was 43years. Twenty-seven per cent of them had a history of systemic disease. The habit of walking and showering barefoot was the major infection-related factor. Distal and lateral subungual presentation was the most common pattern of clinical presentation. The most frequent non-dermatophyte mould was Neoscytalidium dimidiatum followed by Fusarium spp. No relationship was observed with predisposing factors previously reported in the literature. Clinical features found in this population are indistinguishable from onychomycosis caused by dermatophytes. High prevalence of N.dimidiatum found here was in contrast to a large number of studies where other types of moulds predominate.

Nattrassia mangiferae: An uncommon agent of onychomycosis

Onychomycosis constitutes frequent fungal infections of the nails. It is commonly seen in dermatological practice worldwide. The clinical picture though variable is characterized by alterations in the nail architecture such as changes in color, thickness, onycholysis and onychodystrophy.1 In most cases they are caused by filamentous fungi like dermatophytes or yeasts of the genus Candida.2 However, in a small fraction of cases, the etiological agent comprises of non-dermatophyte molds, belonging to several genera and species.1,3 The prevalence of non-dermatophytic onychomycosis varies widely, depending on the geographical location or the climate, but is more frequent in hot and humid tropical areas.3 They are often considered contaminants or secondary pathogens that invade nails previously damaged by trauma or disease. However, in some cases they actually act as primary pathogens to humans, as has been seen for Nattrassia mangiferae, otherwise better known as a plant pathogen. The objective of this case report is to present a rare case of onychomycosis caused by N. mangiferae in a diabetic adult residing in Mumbai, Maharashtra.

Rhodotorula minuta as onychomycosis agent in a Chinese patient: first report and literature review

Onychomycosis is a common superficial fungal infection, which usually caused by dermatophytes, yeast and non-dermatophytic moulds. Recently, we isolated a Rhodotorula minuta isolate from a 15-year-old immunocompetent girl student in Hangzhou (China) that was identified using microscopy, culture morphology, histological diagnosis, API 20C AUX Yeast Identification Kit and sequencing of the Internal Transcribed Spacer region. In vitro, antifungal susceptibility tests showed that this yeast isolate was susceptible to low concentrations of amphotericin B, itraconazole, voriconazole and 5-flvoriconaz but that it appeared to be dose-dependent susceptible to fluconazole(MIC=16μg/ml). Furthermore, the effective result of therapy with itraconazole against R. minuta was consistent with that of susceptibility tests.

English

Onychomycosis is defined as the fungal infection of the nail by any fungus including non-dermatophytes and yeasts. Tinea unguium is clinically defined as a dermatophytic infection of the nail plate. OBJECTIVES: To assess the prevalence of fungal infections in nail disorders and to find out incidence of dermatophytes, candida and other non-dermatophytic moulds. METHODOLOGY: History of patient was noted. The material was collected from lesions which were inoculated to the media. Slants were incubated and examined. If there was growth of dermatophytes, they were subjected to lactophenol cotton blue staining. RESULTS: Incidence was 100 (out of 260 nail cases). Male: female ratio was 1.3:1.69% presented with subungual hyperkeratosis. Distal subungual onychomycosis was most common (51%), proximal (46%) and superficial white (3%). Predisposing factor- occupation associated with wet work (48%). Commonly isolated species were dermatophytes (31%) in which more common was trichophyton rubrum (27%), Non dermatophytes (48%), Aspergillus species (41%), and candida albicans (4%). INTERPRETATION AND CONCLUSION: Finger nails were commonly affected. Associated diseases were Tinea pedis, Tinea manum, diabetes mellitus and anemia. It is a significant and important disease which can generate physical, psychological and occupational problems.

Cutaneous Mycoses among Rice Farmers in Anambra State, Nigeria

Rice grain is one of the world's most important food crops, and its cultivation is a major occupation in Anambra State, Nigeria. These rice farmers are exposed to various agents that predispose them to cutaneous mycoses. The aim of this work was to screen rice farmers for lesions suggestive of cutaneous mycoses and to isolate and identify fungal agents associated with the infection. This survey was carried out between November 2009 and June 2011 in Anambra State, Nigeria. Clinical samples collected from 201 farmers with lesions suggestive of cutaneous mycoses were processed and the organisms identified. Questionnaires were used to obtain other necessary data and were statistically analyzed. Of the 2,580 rice farmers screened, 201 (7.79%) showed positive lesions. Organisms recovered included Microsporum audouinii, Microsporum ferrugineum, Trichophyton megnini, Trichophyton tonsurans, Trichophyton rubrum, Aspergillus terrus, Aspergillus candidus, Aspergillus scleriotorum, Aspergillus niger, Aspergillus flavus, Scopulariopsis sp., Chrysosporium sp., Eupenicillium javanicum, Fusarium sp., Penicillium aculeatum, and Penicillium pinophilum. At the end of this work, onychomycosis was observed to be the most prevalent with nondermatophyte molds now becoming very important agents of cutaneous mycoses among rice farmer.

Therapies for the treatment of onychomycosis

Onychomycosis treatments include nail avulsion and debridement by chemical or surgical procedures, topical and oral antifungals, and device-based therapies. The advantages, disadvantages, and limitations of the different types of treatments—including the most commonly prescribed topical (ciclopirox) and oral (terbinafine, itraconazole, and fluconazole) treatments for onychomycosis caused by dermatophytes, non-dermatophyte molds, and yeasts—are reviewed. Safety and efficacy data for the healthy adult population and for special populations such as children and diabetic patients have confirmed the importance of proper mycological diagnosis before the initiation of therapy as well as the evaluation of the risks and benefits of the different treatments.

Prevalence and etiology of onychomycosis in the HIV-infected Mexican population

Onychomycosis is a fungal infection of the nail caused by dermatophytes, yeasts, and non-dermatophyte molds. Human immunodeficiency virus (HIV)-infected patients are predisposed to this infection. In a cross-sectional study, we estimated the prevalence of onychomycosis and the frequency of fungal agents among HIV-infected patients in Mexico. We enrolled HIV-infected patients diagnosed clinically with onychomycosis from 2008 to 2010. Samples were collected from 300 (84% men) HIV-positive patients by scraping of subungual hyperkeratotic debris and nail plate clipping. All specimens were subjected to culture on Sabouraud agar, Mycosel™ agar, direct microscopy with potassium hydroxide (KOH) and the cultures were incubated at 35°C for 4 weeks. The prevalence and the 95% binomial confidence intervals were calculated. The mean age (± SD) was 37 ± 9 years. One hundred and twenty-four patients (41%) had clinical signs of onychomycosis and 51 (17%) produced a positive culture. Candida parapsilosis was the most frequently isolated microorganism (13 patients, 20%), followed by Trichophyton rubrum (11 patients, 17%).

Epidemiology, diagnosis and management of superficial mycoses: ours three years retrospective analysis

Mycotic infections of the skin, hair and nails are disorder with high prevalence. Dermatophytes are the most frequently etiologic agents followed by yeasts and non-dermatophyte moulds. The geographic distribution is variable because of migration, lifestyle and socio-economics conditions. In this study, based on ours three years retrospective data analysis, we evaluate the epidemiology of etiologic agents, diagnosis and management of superficial mycoses. Our data and our experience suggest the importance of this microbiological diagnosis and the role of the Clinical Microbiologist to assess with Dermatologist and Primary Care Phyisician an appropriate diagnostic and therapeutic plan.

Molecular determination of nondermatophyte mold infections and mixed infections containing dermatophytes in putative onychomychosis patients referred to a dermatologist

Molecular determination of nondermatophyte mold infections and mixed infections containing dermatophytes in putative onychomychosis patients referred to a dermatologist

Aspergillus terreus complex: an emergent opportunistic agent of Onychomycosis

The incidence of onychomycosis due to non-dermatophyte moulds (NDM) is increasing. Aspergillus terreus is relatively undocumented as an agent of this fungal infection. The aim of this work is to show the prevalence of onychomycosis caused by A. terreus and to describe its clinical features. Nail samples were collected for microscopic examination and culturing in selective media. All cases of onychomycosis due to NDM were confirmed by a second sample. Aspergillus terreus isolates were identified through their morphological characteristics and using molecular methods. A total of 2485 samples were obtained. Positive cultures were obtained in 1639 samples. From 124 NDM confirmed cultures, 23 were identified as A. terreus (18.5%). Superficial white onychomycosis was the most frequent clinical pattern. A high percentage was found in fingernails. The prevalence of A. terreus in this study considerably exceeded the percentages reported by other authors. Onychomycosis due to A. terreus presents similar clinical patterns to those caused by dermatophytes, but is difficult to eradicate and is associated with less predictable treatment outcomes. Better knowledge of the aetiology of A. terreus may be important for accomplishing more accurate and effective treatment.

Studies on microscopic technique and culture on Sabouraud's dextrose agar medium for diagnosis of dermatophytes infection

Dermatophytoses (a fungal infection of the skin, hair and nail, usually caused by dermatophytes) constitutes an important public health problem because of its high prevalence and associated morbidity but not life-threatening. Three genera of dermatophytes are recognized based on the site and pattern of fungal invasion. Dermatophytes are the predominant pathogenic mould, but yeasts (especially Candida albicans) and non-dermatophytic moulds may also be implicated. For accurate diagnosis of dermatophytoses requires microscopic demonstration and isolation and identification by culture. This study evaluates the usefulness of microscopic technique and culture for the isolation and identification of dermatophytes from clinical samples. Thirty samples were included in this study for detection of fungal elements by both methods but sensitivity of microscopic demonstration and culture were 60.0% and 66.7% respectively. As the sensitivity of microscopic demonstration (60.0%) is almost equal to the isolation and identification rate (66.7%), requires further evaluation in large scale as its ready to use format makes the application and microscopy much easier and faster.DOI: http://dx.doi.org/10.3329/kyamcj.v3i1.13658 KYAMC Journal Vol. 3, No.-1, June 2012 pp.235-238

Diagnóstico da Tinea pedis e onicomicose em pacientes do Instituto Nacional de Saúde em Portugal: estudo de 4 anos

Tinea pedis and onychomycosis are two rather diverse clinical manifestations of superficial fungal infections, and their etiologic agents may be dermatophytes, non-dermatophyte moulds or yeasts. This study was designed to statistically describe the data obtained as results of analysis conducted during a four year period on the frequency of Tinea pedis and onychomycosis and their etiologic agents. A questionnaire was distributed from 2006 to 2010 and answered by 186 patients, who were subjected to skin and/or nail sampling. Frequencies of the isolated fungal species were cross-linked with the data obtained with the questionnaire, seeking associations and predisposing factors. One hundred and sixty three fungal isolates were obtained, 24.2% of which composed by more than one fungal species. Most studies report the two pathologies as caused primarily by dermatophytes, followed by yeasts and lastly by non-dermatophytic moulds. Our study does not challenge this trend. We found a frequency of 15.6% of infections caused by dermatophytes (with a total of 42 isolates) of which T. rubrum was the most frequent species (41.4%). There was no significant association (p >0.05) among visible injury and the independent variables tested, namely age, gender, owning pet, education, swimming pools attendance, sports activity and clinical information. Unlike other studies, the variables considered did not show the expected influence on dermatomycosis of the lower limbs. It is hence necessary to conduct further studies to specifically identify which variables do in fact influence such infections.

A Study on Clinico-Mycological Profile, Aetiological Agents and Diagnosis of Onychomycosis at a Government Medical College Hospital in Kashmir

Onychomycosis is a major public health problem with a high incidence, associated morbidity and a long lasting treatment with anti-fungal agents. This study was carried out to know the clinico-mycological pattern of onychomycosis, which could help in the control of this infection. The aim of this study was to determine the prevalence of various causative agents of onychomycosis and to study the clinical and mycological patterns of onychomycosis. This was a prospective study which was carried over a period of one year, from 1(st) February 2011 to 31(st) January 2012 on samples from 150 patients with clinically suspected nail infections, who attended the Dermatology Department of SKIMS Medical college, Kashmir, India. The nails were evaluated clinically and the nail samples were subjected to direct microscopy and culture. 60% samples were found to be positive by direct microscopy and culture. Males were infected more than females. The commonest age group which was infected was the 21-30 years age group. Finger nails were affected more frequently than toe nails and distolateral subungal onychomycosis was the most common clinical type of infection which was seen in 64.44% patients. The aetiological agents were dermatophytes (61.66%), Non-Dermatophyte Moulds (NDM) (31.66%) and yeasts (6.66%). Among dermatophytes, T. rubrum was the commonest aetiological agent. Although dermatophytes were the main causative agents, NDM and yeasts were also not uncommon aetiological agents of onychomycosis. This study also emphasized the need of performing both a direct examination and culture to improve sensitivity. Since onychomycosis can cause physical, psycological and occupational problems, the clinico-epidemiological data can be helpful in development of preventive and diagnostic strategies.

Onychomycosis Caused byChaetomium globosum

Onychomycosis is usually caused by dermatophytes, but some nondermatophytic molds and yeasts are also associated with invasion of nails. The genus Chaetomium is a dematiaceous nondermatophytic mold found in soil and plant debris as a saprophytic fungus. We report the first Korean case of onychomycosis caused by Chaetomium globosum in a 35-year-old male. The patient showed brownish-yellow discoloration and subungual hyperkeratosis on the right toenails (1st and 5th) and left toenails (1st and 4th). Direct microscopic examination of scraping on the potassium hydroxide preparation revealed septate hyphae and repeated cultures on Sabouraud's dextrose agar (SDA) without cycloheximide slants showed the same fast-growing colonies, which were initially velvety white then turned to dark gray to brown. However, there was no growth of colony on SDA with cycloheximide slants. Brown-colored septated hyphae, perithecia and ascospores were shown in the slide culture. The DNA sequence of internal transcribed spacer region of the clinical sample was a 100% match to that of C. globosum strain ATCC 6205 (GenBank accession number EF524036.1). We confirmed C. globosum by KOH mount, colony, and light microscopic morphology and DNA sequence analysis. The patient was treated with 250 mg oral terbinafine daily and topical amorolfine 5% nail lacquer for 3 months.

Onychomycosis due to Rhizomucor in psoriatic patient with HIV infection

Onychomycosis is frequently seen in dermatological clinical practice worldwide. The causative agents are usually two pathogenic groups of fungi namely, dermatophytes and yeasts of the genus Candida. In some cases, non-dermatophytic molds belonging to different genera and species may be the etiological agents. We report an unusual case of onychomycosis in an HIV-positive psoriatic patient caused by Rhizomucor pusillus, which has not been mentioned in the literature before. Our finding underline the fact that fungal species appearing as contaminants should be evaluated by proper clinical-mycological correlation to ensure an accurate diagnosis.

Onychomycosis in Cameroon: a clinical and epidemiological study among dermatological patients

There are currently no studies on epidemiology and clinical aspects of nail fungal infections in the general population of Cameroon. Two series of patients observed at a hospital dermatological service of Yaoundé and in a volunteer service of Douala were evaluated. All the patients, regardless of the reason for the consultation, were examined by an expert dermatologist to discover signs of onychomycosis. Patients with suspected nail lesions underwent mycological examination according to the standard techniques. Among 590 subjects (317 males and 273 females), aged 16-83 years, onychomycosis was mycologically confirmed in 52 cases (8.8%). The infection was most common in the fifth decade. Fingernails were affected in 12 cases, toenails in 30 cases, and both fingernails and toenails in 10 cases. Dermatophytes were isolated in 57.7% of cases, the most common species being Trichophyton rubrum (16 cases) and Trichophyton violaceum (eight cases). Non-dermatophytic mould, including Aspergillus spp., Fusarium spp., and Neoscytalidium dimidiatum, was found in 10 cases. Onychomycosis was more common in patients from low social-economic classes. This is the first investigation dealing with onychomycosis in Cameroon. These data may be useful for future research and in the development of preventive and educational strategies.