Download - Superficial mycoses
Superficial Mycoses Superficial Mycoses (Dermatophytes)(Dermatophytes)
((Skin PlantsSkin Plants))
SUPERFICIAL MYCOSESSUPERFICIAL MYCOSESThe superficial mycoses are usually confined The superficial mycoses are usually confined
to the outermost layer of skin, hair and do to the outermost layer of skin, hair and do not invade living tissues. not invade living tissues.
Cutaneous mycosesCutaneous mycoses
Infection of the skin, hair or nails Infection of the skin, hair or nails caused by a group of keratinophilic caused by a group of keratinophilic fungi, called dermatophytesfungi, called dermatophytes
DERMATOPHYTOSISDERMATOPHYTOSIS(=Tinea = Ringworm)(=Tinea = Ringworm)
Tinea means "ringworm" or "moth-like". Dermatologists use the term to refer to a variety of lesions of the skin or scalp.
extend deeper into the epidermis, as well as invasive hair and nail diseases.
DERMATOPHYTESDERMATOPHYTES Digest keratin by their Digest keratin by their
keratinaseskeratinases Resistant to cycloheximideResistant to cycloheximide Classified into Classified into three groupsthree groups
depending on their usual habitatdepending on their usual habitat
DermatophytesDermatophytes3 Genera3 Genera
TrichophytonTrichophyton MicrosporumMicrosporum EpidermophytonEpidermophyton
DERMATOPHYTOSISDERMATOPHYTOSISClinical Classification & Clinical Classification &
ManifestationsManifestations Infection is named according to the Infection is named according to the
anatomic location involved:anatomic location involved:- Tinea corporis - small lesions occurring Tinea corporis - small lesions occurring
anywhere on the bodyanywhere on the body
- Tinea pedis - "athlete's foot". Infection of Tinea pedis - "athlete's foot". Infection of toe webs and soles of feet. toe webs and soles of feet.
- Tinea unguium (onychomycosis) - nails. Tinea unguium (onychomycosis) - nails. Clipped and used for cultureClipped and used for culture
- Tinea capitis - head. Frequently found in Tinea capitis - head. Frequently found in children children
- Tinea barbae - ringworm of the bearded Tinea barbae - ringworm of the bearded areas of the face and neck. areas of the face and neck.
Ecology of DermatophytesEcology of Dermatophytes
To determine the source of To determine the source of infectioninfection
AnthropophilicAnthropophilic ZoophilicZoophilic GeophilicGeophilic
AnthropophilicAnthropophilic
Associated with humans only. Person Associated with humans only. Person -to-person transmission through -to-person transmission through contaminated objects (comb, hat, contaminated objects (comb, hat, etc.)etc.)
ZoophilicZoophilic
Associated with animals. Direct Associated with animals. Direct transmission to humans by close transmission to humans by close contact with animalscontact with animals..
GeophilicGeophilic
Usually found in soil. Usually found in soil. Transmitted to humans by Transmitted to humans by direct exposuredirect exposure..
Trichophyton Trichophyton (19 species)(19 species)
Hair Hair SkinSkin NailsNails
Trichophyton speciesTrichophyton species
Large, smooth, thin wall, septate, pencil-shaped
Trichophyton rubrumTrichophyton rubrum
Causes a chronic infection in Causes a chronic infection in patients with a cell-mediated patients with a cell-mediated immune defect.( Tinea immune defect.( Tinea Capitis).Capitis).
Epidermophyton floccosumEpidermophyton floccosum
SkinSkin NailsNails
Epidermophyton floccosumEpidermophyton floccosum
Bifurcated hyphae with multiple, smooth, club shaped macroconidia )2-4 cells(
MicrosporumMicrosporum(13 species)(13 species)
SkinSkin HairHair
Microsporum speciesMicrosporum species
Thick wall, spindle shape, multicellular
Microsporum canisMicrosporum canis
Most common etiologic agent Most common etiologic agent of tineaof tinea
DERMATOPHYTOSISDERMATOPHYTOSISDiagnosisDiagnosis
I. ClinicalI. ClinicalAppearanceAppearanceWood’s lamp (UV, 365 nm) Wood’s lamp (UV, 365 nm) II. Lab II. Lab A.A. Direct microscopic examination Direct microscopic examination(10-25% KOH)(10-25% KOH)
DERMATOPHYTOSISDERMATOPHYTOSISDiagnosisDiagnosis
B.B. Culture CultureMycobiotic agar Mycobiotic agar Sabouraud dextrose agar Sabouraud dextrose agar
Dermatophytes CultureDermatophytes Culture
Dermatophyte CultureDermatophyte Culture
Black collection card
DERMATOPHYTOSISDERMATOPHYTOSISTreatmentTreatment
Topical Topical Miconazole, clotrimazole, Miconazole, clotrimazole, econazole, terbinafine...econazole, terbinafine...
OralOralGriseofulvinGriseofulvinKetaconazoleKetaconazoleItraconazoleItraconazoleTerbinafineTerbinafine
SUPERFICIAL MYCOSESSUPERFICIAL MYCOSESPityriasis versicolor Pityriasis versicolor Tinea nigraTinea nigraBlack piedraBlack piedraWhite piedraWhite piedraKeratomycosisKeratomycosis
PITYRIASIS VERSICOLORPITYRIASIS VERSICOLOR(Tinea versicolor)(Tinea versicolor)
Superficial chronic infection of Superficial chronic infection of Stratum corneumStratum corneum
Etio: Etio: Malassezia furfur Malassezia furfur (Pityrosporum orbiculare)(Pityrosporum orbiculare) (Lipophilic yeast)(Lipophilic yeast)
Clinical findings: Clinical findings: Hyperpigmented Hyperpigmented or depigmented maculae on or depigmented maculae on chest, back, arms, abdomenchest, back, arms, abdomen
- Characterized by a blotchy discoloration of Characterized by a blotchy discoloration of skin which may itch.skin which may itch.
- Up to 25% of the general population may have this - Up to 25% of the general population may have this lesion at any one time. lesion at any one time.
- Diagnosis is usually possible by direct microscopic - Diagnosis is usually possible by direct microscopic examination of KOH-treated skin scrapings which examination of KOH-treated skin scrapings which show a typical aspect of mycelia and spores show a typical aspect of mycelia and spores described as "spaghetti and meatballs.“described as "spaghetti and meatballs.“
PITYRIASIS PITYRIASIS VERSICOLORVERSICOLOR
Treatm.: Treatm.: Topical selenium Topical selenium sulfidesulfideOral ketaconazoleOral ketaconazole Oral itraconazoleOral itraconazole
TINEA NIGRATINEA NIGRA Superficial chronic infection of Superficial chronic infection of
Stratum corneumStratum corneum Etio: Etio: HortaeHortae (Exophiala) (Exophiala)
werneckii werneckii (pigmented)(pigmented) Frequent in tropical areasFrequent in tropical areas Clinical findings:Clinical findings: Brownish Brownish
maculae on palms, fingers, facemaculae on palms, fingers, face
TINEA NIGRATINEA NIGRA Micr.: Micr.: Septate hyphae and yeast Septate hyphae and yeast
cells (brown in color)cells (brown in color) Culture:Culture: Black colonies Black colonies Treatm.: Treatm.: Topical salicylic acid, Topical salicylic acid,
tincture of iodinetincture of iodine
BLACK PIEDRABLACK PIEDRA Fungal infection of the scalp hairFungal infection of the scalp hair Etio:Etio: Piedraia hortae Piedraia hortae Frequent in tropical areasFrequent in tropical areas Clinical findings: Clinical findings: Discrete, hard, Discrete, hard,
dark brown to black nodules on dark brown to black nodules on the hairthe hair
BLACK PIEDRABLACK PIEDRA
Micr.Micr. Septate pigmented hyphae, Septate pigmented hyphae, and asci; unicellular and fusiform and asci; unicellular and fusiform ascospores with polar filament(s)ascospores with polar filament(s)
Culture:Culture: Brown to black colonies Brown to black colonies Treatm.: Treatm.: Topical salicylic acid, Topical salicylic acid,
azol cremesazol cremes
WHITE PIEDRAWHITE PIEDRA
Fungal infection of facial, Fungal infection of facial, axillary or genital hairaxillary or genital hair
Etio:Etio: Trichosporon Trichosporon (yeast)(yeast) Frequent in tropical and Frequent in tropical and
temperate zonestemperate zones
WHITE PIEDRAWHITE PIEDRA Clinical findings:Clinical findings: Soft, white to Soft, white to
yellowish nodules loosely yellowish nodules loosely attached to the hairattached to the hair
Micr.:Micr.: Intertwined septate Intertwined septate hyphae, blasto- and hyphae, blasto- and arthroconidiaarthroconidia
Culture:Culture: Soft, creamy colonies Soft, creamy colonies Treatm.: Treatm.: Shaving, azolesShaving, azoles
KERATOMYCOSISKERATOMYCOSIS(=Mycotic keratitis)(=Mycotic keratitis)
Posttraumatic / postsurgical Posttraumatic / postsurgical corneal inf. corneal inf.
Etio:Etio: Saprophytic fungi Saprophytic fungi ((AspergillusAspergillus, , Fusarium, Fusarium, Alternaria, Candida), Alternaria, Candida), Histoplasma capsulatumHistoplasma capsulatum
Clinical findings: Clinical findings: Corneal ulcerCorneal ulcer
KERATOMYCOSISKERATOMYCOSIS Micr.:Micr.: Hyphae in corneal Hyphae in corneal
scrapingsscrapings Treatm.:Treatm.: Surgery (keratoplasty)Surgery (keratoplasty)
Topical pimaricinTopical pimaricin NystatinNystatin Amphotericin BAmphotericin B