Epidemiology of dermatomycoses of humans in central Poland. Part I--Superficial infections caused by yeasts and moulds

Nondermatophytic filamentous fungi infection in South America--reality or misdiagnosis?

For the last 10 years, a steady increment in the diagnosis of nondermatophyte filamentous fungal infections has been observed. This trend also applies to the valuation of the medical mycology. It can be attributed, in part, to the increased concern of the population with the aesthetic aspect, the easiest access to health information, and the increased demand for specialized jobs. Moreover, increase in the diagnosis of new emerging fungi is also caused by the improvement of the diagnostic techniques available as well as the qualification and constant update of the professionals in medical mycology. Another relevant aspect is the valorization of medical mycology in the medical curriculum. Misdiagnosis can lead to treatment failures, because not all nail diseases are caused by fungi. Therefore, the importance of clinical diagnosis is strictly associated with laboratory results.

Laboratory-based epidemiological study of superficial fungal infections

Dermatophytosis continues to be a worldwide problem, constituting a large bulk of cases attending the dermatology outpatient's department in tropical countries. Variable climatic conditions and multiple etiological agents, whose individual prevalence varies with time, prompted an attempt to define the current pattern and etiologic prevalence in our locality, and compare them with earlier studies from different centers. Of consenting patients clinically diagnosed to have superficial fungal infections, 1975 were investigated in the laboratory. All the specimens collected from patient skin, hair or nails were subjected to direct microscopy examination in 10% potassium hydroxide (KOH) and fungal culture. Confirmed diagnosis was made only if specimen was KOH and/or culture positive. Male : female ratio was 1.65 : 1. Tinea corporis (21.4%), onychomycoses (14.7%) and tinea capitis (6.2%) were the most common laboratory-confirmed infections. Only 909 patients (47%) out of 1035 clinically suspected patients had evidence of fungal infection by either microscopy and/or culture. Of these 909 patients, 787 (86.5%) were both KOH and culture positive, 25 (2.7%) were KOH negative and culture positive, while 97 (10.6%) were KOH positive but culture negative. In 1051 patients (53%), no evidence of fungal infection was seen. Trichophyton rubrum was the most commonly isolated dermatophyte (55.2%) followed by Trichophyton mentagrophytes (19.6%) and Trichophyton tonsurans (2.9%). Candida sp. accounted for 16% of all isolates. Non-dermatophyte moulds (NDM) were isolated only in patients with onychomycoses. Our study revealed a male preponderance, tinea corporis as the commonest clinical type, and dermatophytes as the commonest mycological isolates, which is in agreement with earlier studies. Relying on clinical diagnosis alone without laboratory confirmation may result in overestimation of the problem as evidenced in other studies as compared to our study. Rarely reported NDM appear to be important etiological agents of onychomycoses.

Characteristics of superficial mycoses in Malta

BACKGROUND

A study was conducted to determine the chief agents of superficial mycoses in Malta. Data were collected over a 5-year period from mycologic investigations carried out on all dermatologic specimens sent to the Mycology Laboratory at St. Luke's Hospital in Malta.

METHODS

In the period between January 1995 and December 1999, a total of 1271 specimens from skin, nails, or hair were collected from 1200 clinically suspected cases of dermatomycoses.

RESULTS

The fungi cultivated included dermatophytes (n = 371), yeasts (n = 33), and nondermatophyte filamentous fungi (n = 12). Trichophyton rubrum (n = 121) was the most prevalent, followed by Microsporum canis (n = 109), T. mentagrophytes (n = 80), M. gypseum (n = 27), Epidermophyton floccosum (n = 17), T. soudanense (n = 10), T. tonsurans (n = 2), T. verrucosum (n = 2), M. persicolor (n = 1), and T. violaceum (n = 1). Candida species were also cultivated, with C. parapsilosis (n = 14) being the most common, followed by C. albicans (n = 12) and C. tropicalis (n = 6). Nondermatophyte filamentous fungi were isolated from nail specimens only.

CONCLUSIONS

In this study, superficial fungal infections were reported more commonly in female (n = 207) than in male (n = 182) patients. M. canis was the chief agent of tinea capitis and tinea corporis, whilst T. rubrum was the main causative agent of tinea pedis, tinea manuum, and tinea unguium. Onychomycosis due to Candida species was more common in female than in male patients.

Epidemiology of dermatomycoses of humans in central Poland. Part IV. Onychomycosis due to dermatophytes

The total number of dermatophytoses (7393) included 1567 (21.2%) cases of onychomycosis. Etiological factors in descending order were: Trichophyton rubrum (58.8%), Trichophyton mentagrophytes var. granulosum (26.2%), T. mentagrophytes var. quinckeanum, T. mentagrophytes var. interdigitale (5.1%), Trichophyton tonsurans (4.1%), Trichophyton violaceum (1.5%), Trichophyton spec. (1.1%). An increase in the incidence was noted between 1994 and 1996. At present, onychomycosis is third by incidence among all clinical forms of dermatophyte infections of skin and skin appendages in the Lódź region.

Epidemiology of dermatomycoses of humans in central Poland. Part V. Tinea corporis

The total number of dermatophytoses (7393) included 2204 (29.8%) cases of tinea glabrosa. Etiological factors in descending order were: Microsporum canis (23.5%), Trichophyton mentagrophytes var. granulosum (21.6%), Trichophyton rubrum (17.8%), Trichophyton tonsurans (10.4%), Epidermophyton floccosum (7.7%), T. mentagrophytes var. quinckeanum (6.0%), Microsporum gypseum (5.3%), Trichophyton violaceum (3.7%), T. mentagrophytes var. interdigitale (2.3%), Microsporum equinum (0.7%), Trichophyton verrucosum (0.4%), Trichophyton spec. (0.4%), Microsporum cookei (0.14%). At present tinea glabrosa is dominant among all clinical forms of dermatophyte infections of skin and skin appendages in the Lódź region.

Epidemiology of dermatomycoses of humans in central Poland. Part III. Tinea pedis

The total number of dermatophytoses (7393) included 2025 (27.4%) tinea pedis cases. Etiological factors in descending order by contribution were: Trichophyton rubrum (41.7%), Trichophyton mentagrophytes var. granulosum (30.9%), T. mentagrophytes var. interdigitale (10.0%), Epidermophyton floccosum (7.4%), T. mentagrophytes var. quinckeanum (6.9%), Trichophyton tonsurans (2.3%), Trichophyton spec. (0.4%), Trichophyton terrestre (0.2%), Trichophyton violaceum (0.1%). In the years 1987-93 the incidence of tinea pedis substantially increased over 1994-96. Today tinea pedis is second by incidence among all clinical forms of dermatophyte infections of skin and skin appendages in the Lódź region.

Epidemiology of dermatomycoses of humans in Central Poland. Part II--Non-dermatophyte infections of nails and periungual walls

This study presents the epidemiology of dermatomycoses and their etiological agents of people living in the Lódź region, Central Poland, over the years 1987-1996. The study comprised a total of 25,737 patients. Positive mycological results were obtained for 14,084 patients (54.7%). The total number of 14,295 of positive mycological results included 6902 (48.3%) isolations of non-dermatophyte fungi. Among these positive results, isolations from subjects with infections of nails and periungual walls amounted to 2034 (29.5%). Candida albicans (59.9%) and Aspergillus sp. (17.3%) were major etiological factors of those infections. The decade in question was marked by a steady growth in incidence of the infections studied, especially over the years 1994-1996.