Superficial fungus

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Introduction / General:

  • Surface fungi are skin infections caused by microscopic fungi (dermatophytes, yeasts, moulds) that cause various features affecting the skin, dying and mucous membranes
  • The source of the infestation may be:

Anthropophile: human-to-human contamination

Zoophile: contact with animals

Geophile: from the ground

Or from saprophyte fungus of the skin or mucous membranes

Dermatophytoses (or dermatophyties)

Definition:

  • Are conditions caused by dermatophytes that are keratinolytic filamentous fungi that multiply in two ways (sexed and asexual). There are three genres:

Trichophyton: with several species

Microsporum: with several species

Epidermophyton: with a single species (Epidermophyton floccosum)

  • Dermatophytes attack stratum corneum, hair and hair, responsible for various clinical charts (damage to hairless skin, hair, nails and creases)

Dermatophytoses of hairless skin (outside the folds)

  • Tinea corporis or Tinea circinata were called "circumed herpes" because of their rounded, circumed appearance, all dermatophytes are pathogenic, can affect all ages
  • Clinical: after an incubation period of 3 weeks, appears a rash-squamous, punctiform, pruriginous, centrifugal, progressional spot, resulting in the formation of a round lesion, offering 2 areas to describe:

Border: erythemato-scaly or erythemato-vesiculatory, active where mycelian filaments swarm

Centre: slightly wrinkled, on the way to recovery

  • Differential diagnosis: can be done with contact eczema, psoriasis, the initial lesion of Gilbert's pink pityriasis…
  • Mycological examination: is done before any antifungal treatment or at a distance from it (more than a month of stopping), at the edge of the lesions, which shows mycelian filaments: this positive diagnosis allows to treat the patient and begin the investigation Epidemiological
  • Culture: on middle of Sabouraud, asks 3-4 weeks to determine the genus and species in question
  • Treatment: local if lesions are limited (imidazole derivative, Ciclopiroxolamine, Terbinafine). In the case of extensive, inflammatory or multiple lesions (more than 3), oral treatment may be used from 15 days to one month: Griséofulvine, Terbinafine

Dermatophytoses of the great folds

Description type: inguino-crural dermatophytic intertrigo

  • Was called "Hebra Marginal Eczema", a condition that often affects adults with male predominance
  • Favourable factors: heat, sweating, wearing synthetic clothing…
  • Clinical: the beginning is made by an erythemato-scaly lozenge at the bottom of the inguinal fold, unilaterally, which gradually extends achieving a tablecloth with polycyclic border (continuous or discontinuous), active in relation to the center that tends to heal. This aspect can become bilateral and extend backwards towards the inter-fessier fold, favoured by the application of dermocorticoids
  • Differential diagnosis: can be done with inverted psoriasis, candidosic intertrigo, erythrasma (a condition that produces brownish tablecloths spread over the 2 folds, whose pathogen is a Gram bacterium: Corynebacterium minutissimum, red-coral fluorescence under Wood's light is characteristic, treatment is antibiotic: erythromycin)
  • Mycological examination / Treatment: Ditto

Dermatophytoses of small folds

Description type: intertrigo inter-toe

  • Formerly called "athlete's foot", adult affection with slight male predominance
  • Favourable factors: wearing closed shoes, heat, sweating, swimming in swimming pools
  • Clinical: results in a simple crack at the bottom of the crease, lined with slats of whitish dander, accompanied by intense pruritus and unpleasant smell, which can affect all the inter-toe spaces especially the last 2 (3rd and 4th space). The inter-toe intertrigo can extend to the back of the toes and foot with dry, flaking. You can have a bacterial overinfection with pain where it can be a gateway for an erysipelas
  • Mycological examination / Treatment: Ditto

Scalp moths

  • Also called "Tinea capitis", they are caused by dermatophytes that give hair parasitism, moths mainly affect children (rarely adults) and are common in developing countries
  • There are three types of moths:

Mowing moths: featuring microsporic mowing moths and trichphytic mowing moths

Inflammatory and suppurative moths: Celse's keron

Favic moths: favus

  • In front of a moth, a good examination, a careful clinical examination of the lesions and the rest of the body, carry out further examinations if possible (Wood light, direct mycological examination and culture), this helps to guide the investigation epidemiological and treat the patient and affected individuals if they exist
  • Microsporic mowing moths:

Agents:

  • Microsporum canis: zoophile dermatophyte, the most common in Algeria and the Maghreb
  • Microsporum audouinii: anthropophilic dermatophyte, seems more common in Europe
  • Microsporum langeronii: anthropophilic dermatophyte, common in Africa
  • And other species…

Epidemiology: represents 16-20% of scalp moths in Algeria, affecting both sexes, the age of onset is between 6 and 10 years

Clinical: performs erythemato-scaly alopetic, rounded or oval lesions, 2-5 cm in diameter, with net limits, few, 2-4 on average. The hair, on a scaly plate, is broken a few millimeters (4-6 mm) from the follicular openings, achieving the appearance in a brush, the extraction with the hair clip finds that they are accompanied by bulb

Wood's Light Examination: Reveals a Vivid Green Fluorescence

Mycological examination: direct examination shows microsporic (endo-ectothrix) parasitism, characterized by hair containing mycelial (intrapilar) filaments and surrounded by clusters of spores

Sabouraud medium culture: identifies the species in 2-4 weeks

  • Trichophytic mowing moths:

Agents: always anthropophile

  • Trichophytum violaceum: common anthropophilic dermatophyte in Algeria and around the Mediterranean
  • Trichophyton tonsurans: cosmopolitan
  • Trichophyton Soudanense: especially in Africa
  • And other species…

Epidemiology: it is the most common in Algeria, accounting for 76-80% of all scalp moths, highly contagious, carrying out epidemics in children's communities

Clinical: they make small greyish, alopetic, scaly, irregularly shaped, imprecise limits, a few millimetres in diameter, very numerous or even hundreds. Sick hair is cut at the scalp, stuck in the dander (pseudo-comedons), the hair clip extraction finds that it is not accompanied by bulbs

Wood's Light Review: No Fluorescence

Mycological examination: direct examination shows endothrix-type parasitism (hair stuffed with spores)

Sabouraud medium culture: identifies the species in question in 3-4 weeks

  • Inflammatory and suppurative moths (Celse's keron):

Agents: they are often zoophiles:

  • Trichophyton verrucosum: ochraceum variety
  • Trichophytum mentagrophyte

Epidemiology: rare, 2% of all moths in Algeria, non-contagious, in the form of sporadic cases in livestock (cattle and equines) but also in urban areas

Clinical: it begins with an erythematous, slightly scaly spot, 2-5 cm in diameter, which becomes inflammatory and congestive from the 2nd week, it thickens and rises, surters by all follicular openings, causing the fall of the hair (macaroon appearance)

Wood's Light Review: No Fluorescence

Mycological examination: direct examination shows that there are two types of parasitism:

  • Megaspore: characterized by a hair containing mycelian filaments and spores of 4-8 m, arranged in chains on the outside of the hair
  • Microid: the same look as the previous one, but the spores have a smaller size

Sabouraud medium culture: identifies the species in 2-4 weeks

Evolution:

  • Favorable: with a reverse chronology to the constitution of the macaroon
  • Unfavourable: with definitive scarring alopecia
  • Favic moths (favus):

Agent: Trichophytum schonleinii: anthropophilic dermatophyte, exclusive agent on favus

Epidemiology: less than 1% of scalp moths, highly contagious

Clinical: starts with scaly erythemato-lesions, which evolve into a typical appearance called a "favic bucket": it is a rounded crust, with a raised edge of about 0.5 cm, its surface is depressed in the center, cup-shaped, its color is yellow saffron, it emerges from these lesions a characteristic mouse smell, this bucket is crossed by a favebic hair that is never broken, however, it grows badly, it has lost its natural gloss and has the appearance of dry hay

Wood Light Examination: Reveals Greenish Fluorescence

Mycological examination: shows a favic-type parasitism: hair stuffed with mycelian filaments and air bubbles with no spores

Culture on the middle of Sabouraud: identifies the species

  • Treatment of ringworms:

General measures: the combs and brushes of the patient must be cleaned or burned, shaving the affected hair and in the vicinity of the plates with a disposable razor, stripping of crusty lesions is necessary, cleaning towels, taies pillows and sheets and then iron them. For Kerions, do not incise as this delays healing and can lead to blood contamination

  • School eviction remains mandatory for anthropophilic moths

Local treatment: local antifungal, lotion, 2x/d and antifungal shampoo

General treatment:

  • Griséofulvine: at the dose of 20-25 mg/kg/d and 1 g/d in adults, for 6-8 weeks, it is a fungiistatic and also has an anti-inflammatory action, must be taken in the middle of meals, very active on microsporic and inflammatory teinges

Side effects: skin rash, nausea

  • Terbinafine: fungicide, at a dose of 125 mg/d in children 20 to 40 kg and 62.5 mg/d if it weighs less than 20 kg and 250 mg/d in adults, by monitoring blood formula and liver enzymes, very active on trichophytic moths
  • Itraconazole

Dermatophytic Onyxis

  • It is a damage to the nails by dermatophytes, dermatophytic onyxis is isolated without peri-onyxis
  • We often find at issue: Trichophyton rubrum, Trichophyton violoaceum...
  • Toenails are more affected than hand nails
  • There are also triggers: climate, intra-familial transmission, sports, individual factors…
  • Ungueal impairment can take 4 aspects, depending on the pathway of the fungus into the ungueal apparatus:

Onychomycosis of distortion-lateral

Proximal Onychomycosis: Reaches the Matrix

Superficial Leuconychia: corresponds to an injury to the superficial part of the ungueal tablet without affecting the nail bed

Total Onychodystrophy: is the ultimate step in the destruction of the nail by the fungus

  • Evolution: chronic, reaching from near to near the other nails
  • Treatment: depends on the damage to the nail and the mushroom isolated in cultivation: it is possible to settle for a local treatment if the damage to the nail is limited (Amorolfine in solution or Ciclopiroxolamine in solution), oral treatment is necessary in case (Terbinafine). Duration of treatment: several months

Levuroses

Yeasts that are usually non-pathogenic can become so under special circumstances: Mallassezia, Candida albicans...

Superficial skin candidoses

  • These are skin, mucous, dinghy conditions, caused by levuriform fungi of the genus Candida, of which the species albicans is the most incriminated
  • Favourable factors: diabetes, obesity, immunodepression, corticosteroid therapy…
  • Candidoses oropharyngeals: these are:

Perlèche: results in a painful crack in the bottom of the lipcurnal commissure, covered with a whitish, uni- or bilateral coating, it is contagious, they are to be differentiated from other pearls (oily, syphilitic,  irritative dermatitis…)

Candidosic Cheilitis: inflammation of the lips with flaking and sometimes cracking, subaigst or chronic

Candidosic stomatitis: inflammation of the oral mucosa, diffuse or localized, presenting in three forms (erythmatous, pseudo-membrane (muguet) or hyperplastic) that are accompanied by dryness of the mouth and cooking sensation, (mostly acid) feeding, the infant refuses to breast-feed

  • Candidosic intertrigos:

Large folds: the infection spreads symmetrically in a mirror on the banks of the folds, creating red, homogeneous and varnished tablecloths, on the periphery, these lesions are lined with whitish pustules and sometimes with a "desquamative collar" appearance, the lesions are very pruriginous with a feeling of burning or pain, the bottom is cracked

  • Adult-friendly factors: obesity, diabetes, maceration, lack of hygiene…

Small folds: candidiasis concern the first or second plantar inter-toe spaces, at the hands, the damage affects the 3rd or 4th interdigital space and it is necessary to look for candidiasis under the covenant, again, we are looking for a diabetes, general and especially local factors (humidity of the hands among restaurateurs, cooks, wearing safety shoes…)

Anogenital candidiasis: anite, vulvitis, vulvo-vaginitis, balanoposthitis.       They are often accompanied by factors that favour

Peri-onyxis and onyxis: a condition that most often affects women, the nails of the hands are most often affected, favoured by the handling of sugary products and aggravated by contact with household products. The condition begins with a red and inflammatory peri-onyxis, painful and suppurating, the pressure of the bulge deafens the pus, the ungueal reach is secondary, results in spots (whiteish, yellowish, greenish), the ungueal blade is Thickened

  • Mycological examination:

Direct examination: from different samples, allows you to see budding yeasts or pseudo-filamentous yeasts

Cultivation on the middle of Sabouraud: allows you to observe in 24-48 hours creamy and whitish colonies

  • Treatment of candidiasis:

At the skin level: local antifungal treatment is sufficient (Ciclopiroxolamine, nitrogen derivatives), if the lesions are significant, oral Fluconazole is used for 15 days

On mucous membranes: C. albicans is saprophyte, which leads to treating only lesions on which the culture has isolated many colonies with positive direct examination

  • Oral candidiasis: Amphoterin B can be used locally, to keep in mouthwash or local Miconazole, if the lesions are significant, oral Fluconazole should be added, the favouring causes should also be eliminated and the right one must be checked for dental hygiene

Ungueal: general treatment: Fluconazole for several months, or not associated with local treatment (Amorolfine)

Pityriasis Versicolor (PV)

  • It is a very common epidermomycosis, cosmopolitan, benign, it is due to lipophilic yeasts of the genus Malassezia, these yeasts are commensales of the human skin
  • More common in adolescents and young adults
  • It is recurrent because there are predisposing factors (often difficult to control): genetic (probable), lipid (preferential damage to areas rich in sebaceous glands), sweat secretion (physical activity, wearing uniforms  occlusive, climate), hormonal (hypercorticism, pregnancy)
  • Clinical: makes finely scaly macules, of whitish, buff yellow, rounded or oval colour, sometimes polycyclic, drawing real maps, with hypo- or hyper-pigmented lesions, there is no pruritus, lesions mainly sit at the seborrheic zones (face, neck, upper part of the chest because it is a lipophilic yeast), the pressure of a dander causes its detachment (sign of Copeau), the achroming shape is very visible after  tan, there are pigmented, dark brown or even black shapes, erythematous
  • Direct mycological examination: after a scotch test (an adhesive is spread on the skin and the most superficial layer is removed, then observed under a microscope), reveals clusters of grapes
  • Culture: identifies the species in question
  • Wood's light examination: greenish yellow fluorescence
  • Treatment: imidazole antifungal or foaming gel or Selenium sulphide (2.5%), in resistant forms, Ketoconazole (200 mg, per bone, for 10 days)
Ringworm Pilary parasitism Wood Lamp Dermatophyte Transmission
Microsporic Microsporic: small intrapilary filaments, 2-m spores, sheathing around the hair Green Fluorescence

Mr. cudouinii
M. largeronii
M. rivalierii
M. ferrugineum

Anthropophile:
Europe
Africa Africa
Asia
Microsporic Mr. canis Zoophile (cat, dog), cosmopolitan
Trichophytic  Endothrix: 4m spores, intrapilary, numerous, short broken hair No fluorescence T. soudanense T. violaceum T. tonsurans T. roseceum Anthropophile: Black Africa North Africa Cosmopolitan Portugal
Inflammatory

Microide: chain of spores, extrapilaires, 2 m No fluorescence T. mentagraphytes Zoophile: dog, horse, rabbit, guinea pig
Megaspore: extra-hair chains of spores, 5-6 m T. ochraceum Zoophile: bovid
Other types T. violaceum T. soudanense M. gypseum Anthropophile Geophile Anthropophile
Favus Favique: intrapilary filaments only, unconcroed hair Green Fluorescence T. schonleinii Anthropophile: North Africa

M – Microsporum / T – Trichophyton

  Griseofulvine Itraconazole Fluconazole Terbinafine
Dermatophyte ++ ++ + +++
Yeast ++ ++ +-
Mold ++ ++
Malassezia ++ +

'effective'/ 'ineffective'/ ineffective

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