Mycose — Wikipedia

A yeast infection is a fungal infection caused by one or more species of parasitic or saprophytic microchampignons. The fungal pathologies studied by medical mycology, are often subdivided into infections called superficial, subcutaneous mycoses and systemic yeast infections ^{[ first ]} . They most often concern small areas of the skin and/or mucous membranes. Much more rarely the fungus invades internal organs (when it comes to the lungs they can cause an infection evoking pneumonia or pulmonary tuberculosis).

Serious infections usually occur only in immunodeficient individuals, that is to say, the immune system of which has been inhibited or destroyed either by a disease such as AIDS or by anticancer drugs or by radiation. They can also concern patients treated with steroid hormones such as cortisol, suffering from meal diabetes, and treated with antibiotics.

Many species of fungi or microscopic yeasts can be pathogenic for humans under certain conditions. New species can still be discovered. The progress of knowledge of the genome of dermatophytes have recently led to reclassify the old zoophile variety Trichophyton mentagrophytes was. in Trichophyton mentagrophytes (distinct species).

Skin microlanesions or a decrease in immune defenses allow them to penetrate the epidermis and then the dermis, or mucous membranes.

Two main types of yeast infections are:

Dermatophytia and onychomycosis can thus be caused by at least three species of dermatophytes anthropophiles :

1. T. Red
2. T. interdigitale And
3. Epidermophyton floccosum .

T. interdigitale (formerly called T. mentagrophytes ) is today the second most common dermatophyte in Germany ^{[ 3 ]} .
All these dermatophytes target in the skin layer, in the hair or in the nail cytokeratin, a hard and firm protein material, which they degrade to feed on it. For this they secrete a dedicated enzyme: keratinase, but they also help other proteolytic enzymes (including nucleases) and dioxygenase cysteine ​​considered as “virulence factors” ^{[ 3 ]} .

Several predisposition factors have been discovered for infection by tinea foot And tinea : these are mainly:

• circulatory disorders affecting the lower limbs ^{[ 3 ]} ;
• Metabolic disorders such as diabetes mellitus ^{[ 3 ]} (higher risk of Tinea Pedis and Onychomycosis ^{[ 3 ]} ); Onychomycosis is now considered a predictor of diabetic foot syndrome and diabetics requiring hemodialysis at 88% of onychomycosis more than a non-diabetic ^{[ 3 ]} But it is also “Significantly more frequent if the feet are not washed daily” ^{[ 3 ]} ;
• Cellular immunity disorders (at least for dermatophytosis ^{[ 3 ]} );
• Psoriasis (27% of people with psoriasis whose nail presents a change of appearance have onychomycosis ^{[ 3 ]} );
• Genetic factors and family history (in the case of onychomycosis for which we have shown that “The dominant autosomal heredity of a factor of susceptibility promotes the development of a distal under Until-Undeal Ontychomycosis due to Trichophyton Rubrum” And that certain populations (Jews Ashkénazes for example) are protected from onychomycosis thanks to the Human Leukocyte antigen DR4 (HLA-DR4).

The adjective related to “Mycosis” is ” mycosics “, synonym of ” fungal ». The term “mycotic”, although widely used does not appear in the various dictionaries ^{[ 4 ]} . An exception is the expression “mycotic aneurysm”, a classic complication of infectious endocarditis, but which is however caused by any yeast infection.

The superficial fungal infections of the skin and nails, the more contagious we less contagious depending on the strains and the contexts have a strong prevalence in the world: 20 to 25% of humanity periodically suffers from skin mycoses, most often benign; It is therefore one of the most frequent microbial infections ^{[ 5 ]} . Nail yeast infections affect certain risk groups (including diabetics, psoriasis carriers) more than the general population ^{[ 3 ]} .

In the world Trichophyton Red, T. Interdigital (Mentagrophytes ssp. Interdigital), M. Canis, M. Audouinii, T. tonsurans and T. verrucosum seem to be largely dominant, but “The attack rates and the incidence of specific yeast infections may vary considerably. Local socio-economic conditions and cultural practices can also influence the prevalence of a particular infection in a given area » ^{[ 5 ]} . Thus the athlete’s foot, generally due to T. Red is more widespread in developed countries (wearing closed shoes and socks?) than in poor countries where in conversely scalp yeast (Tinea capital) caused by T. Sudanense or M. Audouinii will be more common ^{[ 5 ]} . Within current species, we observe a high inter- and intra-continental variability of the strains in question and their prevalence ^{[ 5 ]} .

Superficial skin infections linked to Malassezia (Pityriasis Versicolor especially) are very frequent ^{[ 3 ]} .

The most commonly identified pathogens in children and adolescents are the zoophile dermatophytes for whom certain animals (cats, rodents, of which India pigs for example) are sources of infection and transmission; cattle are also increasingly sources of Trichophyton verrucosum (low vaccination rate of livestock and calves in particular); calves and cows are then a source of infection mainly of children and adolescents on vacation on a farm (illness now considered to be an occupational disease and with compulsory reports in Germany) ^{[ 3 ]} .

Contrary to what its Latin name suggests the tank of M. The dog would rather be the cat with the cases studied in Germany for the most frequent contamination on vacation in southern Europe (Spain, Italy, Greece) or Southeast (Balkans, including Bulgaria) or in North Africa (Tunisia, Morocco) ^{[ 3 ]} ; In Italy, 100% of the wandering cats tested were carriers of M. The dog.

Trends [ modifier | Modifier and code ]

• Non -dermatophyte molds (NDM) are increasingly at the origin of the nail onychomycosis ^{[ 3 ]} .
• A phenomenon first gone unnoticed has recently been underlined in Germany is a change of pathogens towards Trichophyton infections (Arthroderma benhamiae) which can cause a ringworm accompanied by severe inflammation in children/adolescents and immunocompromised patients. This evolution has gone unnoticed on the one hand because the disease is not compulsory and on the other hand because this pathogenic microchampignon can, during the diagnosis, be very easily confused with M. The dog, T. Interdigitale, T. Hedgehog or T. Sudanense ). An identification test of A. Benhamiae In skin flakes is now available (PCR-Elisa) ^{[ 3 ]} .
• An emerging pathogen, zoophile dermatophyte transmitted to humans by un threatened hedgehogs imported from Africa in Europe is Trichophyton erinacei , which causes severe inflammation ^{[ 3 ]} .

External yeast infections present for some of the characteristics likely to guide the diagnosis.
This is the case, for example, of a microchampignon like Hendersonula toruloidea that can infect the skin or nails ^{[ 6 ]} or mycoses of the language (also called pearls, lily of the valley … for example due to candida albicans ) which sometimes appear after antibiotic treatment or in people in a state of immune deficit.

Endomycosis (internal mycoses) are much more difficult to detect.

In recent years, biomolecular tests have been developing, which make it possible to detect an increasing number of pathogenic strains, for example in the context of blood tests ^{[ 7 ]} .

Medicines are so -called anti -fungal or fungicide antibiotics. The drugs to ingest have a certain toxicity for the body (microchampignons are part of the natural intestinal flora).

In the case of relatively benign genital candidiasis, a vaginal egg is most often prescribed (example: gynopévaryl). We sometimes complete the treatment with a cream, which we have known recently that it is not necessary to prescribe it to the sexual partner ^{[Ref. necessary]} . If yeast infection frequently returns it is possible to prescribe an egg each month.

In onychomycosis (nail infection) refractory to treatment, keratinization disorders affecting the skin and nails are more frequent than we had previously estimated ^{[ 3 ]} .

In fish [ modifier | Modifier and code ]

Fish mycoses are characterized by fluffy growths such as cluster cotton. Mushrooms attack the parts of the body whose mucus has been damaged. These mycoses are a secondary infection of an existing injury. They can be destroyed by treating the entire bin to the fungicide ^{[ 8 ]} .

In recent years, massive mortalities of amphibians have been due to emerging disease. It is a fungal infection that extends in the world, and which is partly responsible for the decline of the populations of amphibians in the world.

The fungus in question is a chytride (chytridiomycete) called Batrachochytrium dendrobatidis ). The mycosis it causes is called chytridiomycosis. In 2004, 30% of world amphibian species were affected ^{[ 9 ]} .
And “In less than thirty years […] more than 120 species have disappeared and 435 have strongly regressed ” ^{[ ten ]} .

Related articles [ modifier | Modifier and code ]

Bibliography [ modifier | Modifier and code ]

• Al-Shorbaji Fn, Gozlan Re, Roche B, Britton Jr, Andreou D. (2015) The alternate role of direct and environmental transmission in fungal infectious disease in wildlife: threats for biodiversity conservation . Sci Rep. May 20, 2015  ; 5:10368. Epub 2015 May 20 ( résumé ).