scholarly journals Dermatophytes, dermatophytosis in the Caribbean and potential for herbal therapy

2020 ◽  
Vol 1 (1) ◽  
Author(s):  
Harish Gugnani

Introduction: Dermatophytes are a group of morphologically related keratinophilic fungi that invade keratinized tissue (skin, hair, and nails) of humans and warm-blooded animals to produce clinical lesions (dermatophytosis). Clinical lesions are traditionally divided according to the site infected, namely, scalp (tinea capitis), feet (tinea pedis, commonly called “athletes’ foot”), groin, inner thighs, or buttocks (tinea cruris, commonly called “jock itch”), beard (tinea barbae), hands (tinea manuum, toe nails or finger nails (tinea unguium, also called onychomycosis), face, non-bearded area (tinea faciei) and other parts of the body, such as arms, abdomen, or legs (tinea corporis). Dermatophytosis is common world-wide and is caused by species of three genera of dermatophytes, namely Microsporum, Trichophyton, and Epidermophyton. This study presents an update of ecology of different species of dermatophytes and epidemiology of infections caused by them in the Caribbean. Possibility of herbal therapy of these infections as an alternative treatment is also dealt with. Methods: A thorough search of literature was made using PubMed, MEDLINE, Biomed Lib, Med Facts, and different sets of key words, viz. dermatophytes, tineas in Caribbean, occurrence in animals, soil etc. Results: It was revealed that incidence of dermatophytic infections and their epidemiologic characteristics depend on social, geographic, and environmental factors and may change with passage of time. For instance, prior to year 2000, the major cause of tinea capitis in North America for 100 years was Microsporum canis followed by M. audouinii; Since 1950 Trichophyton tonsurans has advanced from Mexico and the Caribbean to be currently a major cause of tinea capitis in North America. The two dermatophytes Microsporum gypseum and M. fulvum, and several Chrysosporium species have been frequently isolated form soils in different countries in the Caribbean. Conclusions: There is almost complete lack of information on human infections due to dermatophytes in several Caribbean countries. The preponderant occurrence of M. fulvum in Anguilla soils with comparatively rare isolation of M. gypseum is a significant observation. The need for further epidemiological studies on dermatophyosis in the Caribbean countries cannot be overemphasized.

Diseases ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 13 ◽  
Author(s):  
Y.O. Adesiji ◽  
F.B. Omolade ◽  
I.A. Aderibigbe ◽  
O. Ogungbe ◽  
O.A. Adefioye ◽  
...  

Tinea capitis is a fungi infection of the scalp that disproportionately affects children in rural and underserved communities in Nigeria. A case-control study was conducted to identify the causative agents and factors that predispose school pupils to tinea capitis in two selected government-owned public primary schools in Osogbo, Southwestern Nigeria. A total of 230 participants were included in the study: 115 cases and 115 controls. Head scrapings were collected from pupils with suspected T. capitis lesions, viewed under Potassium Hydroxide smear microscopy and cultured in Sabouraud’s Dextrose Agar (SDA) for characteristic fungal elements. A total of 105 (91%) samples were successfully cultured, of which 56% (59/105) were from male pupils. Tricophyton rubrum (34%), Tricophyton mentagrophyte (31%) and Microsporum canis (18%) were the most prevalent organisms. Other dermatophytes obtained include Microsporum nanuum (3%), Epidermophyton floccusum (6%), Tricophyton verucosum (1%), and Microsporum gypseum (8%). Pupils between the ages of 4 and 7 years had the highest distribution (67%) followed by those between the ages of 8 and 11 years (39%). Playing with animals, the sharing of combs and not bathing with soap were significantly associated with tinea capitis infection (P < 0.05) in each case. This study showed a high prevalence of tinea capitis caused by the identified dermatophytes in the area.


2007 ◽  
Vol 56 (10) ◽  
pp. 1377-1385 ◽  
Author(s):  
Rahul Sharma ◽  
S. de Hoog ◽  
Wolfgang Presber ◽  
Yvonne Gräser

The zoophilic dermatophyte species Microsporum canis belongs to the Arthroderma otae complex and is known to mate with tester strains of that teleomorph species, at least in the laboratory. Human infections are likely to be acquired from the fur of cats, dogs and horses. Epidemiological studies to reveal sources and routes of infection have been hampered by a lack of polymorphic molecular markers. Human cases mainly concern moderately inflammatory tinea corporis and tinea capitis, but, as cases of highly inflammatory ringworm are also observed, the question arises as to whether all lineages of M. canis are equally virulent to humans. In this study, two microsatellite markers were developed and used to analyse a global set of 101 M. canis strains to reveal patterns of genetic variation and dispersal. Using a Bayesian and a distance approach for structuring the M. canis samples, three populations could be distinguished, with evidence of recombination in one of them (III). This population contained 44 % of the animal isolates and only 9 % of the human strains. Population I, with strictly clonal reproduction (comprising a single multilocus genotype), contained 74 % of the global collection of strains from humans, but only 23 % of the animal strains. From these findings, it was concluded that population differentiation in M. canis is not allopatric, but rather is due to the emergence of a (virulent) genotype that has a high potential to infect the human host. Adaptation of genotypes resulting in a particular clinical manifestation was not evident. Furthermore, isolates from horses did not show a monophyletic clustering.


2021 ◽  
Vol 186 (2) ◽  
pp. 299-305
Author(s):  
Zhihui Yang ◽  
Wei Chen ◽  
Zhe Wan ◽  
Yinggai Song ◽  
Ruoyu Li

AbstractTinea capitis is a type of dermatophyte infection primarily affecting children. We report a case of an elderly woman with well-controlled diabetes mellitus presenting with a six-month history of erythema with yellow crusts on her scalp and extensive erythematous patches with scales on the body skin. She adopted a stray cat before the disease onset. Dermoscopic findings and manifestation under the Wood’s lamp favoured the diagnosis of tinea capitis. Further microscopic examinations of her scalp, including direct KOH and fluorescence stain examination, fungal culture and polymerase chain reaction sequencing identification confirmed the diagnosis of tinea capitis caused by Microsporum canis. Treatment with oral terbinafine was effective. Adult tinea capitis is often misdiagnosed due to its rarity and atypical presentation. However, in some regions, the incidence of tinea capitis in immunocompetent adults is rising which requires the awareness of clinicians. A thorough history (including the animal contacting history), physical examination and further mycological examinations are required for diagnosis. Trichophyton violaceum is the most common dermatophyte species in most regions while adult tinea capitis caused by Microsporum canis is less common. Terbinafine, griseofulvin and itroconazole have been reported to be effective drugs for the treatment of tinea capitis, and terbinafine can be considered as systemic treatment in elderly patients with comorbidities to reduce the drug–drug interaction.


Author(s):  
P. M. Stockdale

Abstract A description is provided for Microsporum canis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Primarily a pathogen of the cat and dog, frequently transmitted to man. Also recorded from the chimpanzee, chinchilla, fox, lion, monkey, pig, rabbit, sheep and tiger. Experimental animals are susceptible to infection. DISEASE: Ringworm (dermatophytosis, tinea). Infected hairs and animal claws usually fluoresce bright green under Wood's light and hairs are surrounded by ectothrix sheaths of small spores in a mosaic arrangement. In cats the lesions are usually inconspicuous. They may occur on any part of the body, but particularly the face and paws, and the whiskers and claws may be involved. In dogs infection is more noticeable, and is characterized by small circular areas of scaling and alopecia, sometimes with oedema and crust formation, on any part of the body. The claws may also be infected. Infections in dogs have a well defined seasonal incidence with a peak in Oct. -Feb., but the incidence in cats is poorly defined (Kaplan & Ivens, Sabouraudia 1: 91-102, 1961). In man the scalp (tinea capitis), glabrous skin (tinea corporis), and rarely the beard (tinea barbae), foot (tinea pedis) and nails (tinea unguium, onychomycosis) may be infected (mycoses). Children are most susceptible, particularly to scalp infection which is very rare in adults. Scalp lesions are scaling, inflammatory areas containing broken hairs or with total hair loss. Pustulation and kerion formation are not uncommon. Skin lesions are circinate, with a scaling centre and vesicular border. Kligman (RMVM 1, 2510; 2, 2484) studied the pathogenesis of tinea capitis caused by M. canis. GEOGRAPHICAL DISTRIBUTION: Africa (Algeria, Angola, Cape Verde Islands, Egypt, French W. Africa, Sahara, Tunisia, Union of S. Africa); Asia (Ceylon, India, Philippines, Turkey); Australasia & Oceania (Australia (N.S.W.), New Zealand); Europe, North America, Central America and West Indies (Costa Rica, Cuba, Guatemala, Mexico, Panama, Puerto Rico); South America (Argentina, Brazil (south of Pernambuco), Chile, Colombia, Ecuador, Peru, Uruguay, Venezuela).


2015 ◽  
Vol 9 (08) ◽  
pp. 865-871 ◽  
Author(s):  
Daiane Heidrich ◽  
Marcelo Rocha Garcia ◽  
Cheila Denise Ottonelli Stopiglia ◽  
Cibele Massotti Magagnin ◽  
Tatiane Caroline Daboit ◽  
...  

Introduction: Dermatophytoses are considered a public health problem. The objectives of this study were to determine the evolution of their prevalence in the metropolitan area of Porto Alegre, Brazil, and to analyze the dermatophyte species distribution according to body site and demographic characteristics of the patients. Methodology: This work was a retrospective analysis of data from patients attending a tertiary care hospital during 1996–2011. Results: There were 9,048 cases with cultures positive for dermatophytes. Trichophyton rubrum occurred in 59.6% of the cases, followed by Trichophyton interdigitale (34%), Microsporum canis (2.6%), Epidermophyton floccosum (1.5%), Microsporum gypseum (1.3%), and Trichophyton tonsurans (0.9%). The angular coefficients for T. interdigitale, E. floccosum, T. rubrum, and M. canis were +1.119, +0.211, -0.826 and -0.324% per year, respectively. Males presented higher prevalence of infection (79.3% versus 53.9%). Tinea unguium occurred in 48.5% of the cases, followed by tinea pedis (33.1%). T. rubrum was the predominant species in all regions of the body except the scalp, where M. canis was responsible for 75% of the cases. Conclusion: Monitoring of the evolution of dermatophytosis tracks changes in prevalence over the years and may assist practical measures for the public health control of this disease.


1889 ◽  
Vol 21 (10) ◽  
pp. 188-193
Author(s):  
A. R. Grote

The tibiæ are usually all spinose, the eyes naked, the body untufted, the form normal, the male antennæ of various structure, pectinated, brushlike simple. The European species are refered by Lederer all to one genus, Agrotis or Hübner. Nervertheless, I think the yellow-winged forms may well be separated under Hiria and Tryphœna. Of these yellow-winged forms, with flattened abdomen, we have only one T. Chardinyi, from Anticosti and Maine, considered identical with the Siberian species of the same name, described orginally by Boisduval under Anarta.


1971 ◽  
Vol 36 (2) ◽  
pp. 170-182 ◽  
Author(s):  
David A. Breternitz ◽  
Alan C. Swedlund ◽  
Duane C. Anderson

AbstractAn isolated burial was excavated from the bank of a tributary of Gordon Creek, Roosevelt National Forest, northern Colorado. A preliminary report was prepared (D. Anderson 1966, 1967) but further analysis of the skeletal material and newly obtained cultural information add significantly to the documentation of the burial.The body of a woman, aged 25-30 years, was given primary interment in a pit coated with red ocher. The body was placed on its left side with the head to the north, was tightly flexed, and was also coated with red ocher. Burial accompaniments include a large precussion flaked biface or preform, a small biface used as a scraping tool, a hammerstone, an end scraper, a preform with fire pocks, cut and incised animal ribs, and a perforated elk incisor. A radiocarbon assay of bone material from the left ilium produced an age of 9700± 250 radiocarbon years: 7750 B.C. (GX-0530).No indications of habitation which might be associated with the burial were located in its immediate vicinity.A reconstruction of the burial ritual is attempted, and the skeletal remains are compared to other early human remains from North America.A summary of this paper was given at the 34th Annual Meeting of the Society for American Archaeology, May 3, 1969, in Milwaukee, Wisconsin.


2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Alena Pecinova ◽  
Zdenek Drahota ◽  
Jana Kovalcikova ◽  
Nikola Kovarova ◽  
Petr Pecina ◽  
...  

Metformin is widely prescribed as a first-choice antihyperglycemic drug for treatment of type 2 diabetes mellitus, and recent epidemiological studies showed its utility also in cancer therapy. Although it is in use since the 1970s, its molecular target, either for antihyperglycemic or antineoplastic action, remains elusive. However, the body of the research on metformin effect oscillates around mitochondrial metabolism, including the function of oxidative phosphorylation (OXPHOS) apparatus. In this study, we focused on direct inhibitory mechanism of biguanides (metformin and phenformin) on OXPHOS complexes and its functional impact, using the model of isolated brown adipose tissue mitochondria. We demonstrate that biguanides nonspecifically target the activities of all respiratory chain dehydrogenases (mitochondrial NADH, succinate, and glycerophosphate dehydrogenases), but only at very high concentrations (10−2–10−1 M) that highly exceed cellular concentrations observed during the treatment. In addition, these concentrations of biguanides also trigger burst of reactive oxygen species production which, in combination with pleiotropic OXPHOS inhibition, can be toxic for the organism. We conclude that the beneficial effect of biguanides should probably be associated with subtler mechanism, different from the generalized inhibition of the respiratory chain.


Sign in / Sign up

Export Citation Format

Share Document