SUPERFICIAL MYCOSESSUPERFICIAL MYCOSES

Prof. Akram Hossain Prof. Akram Hossain Feb 2009Feb 2009

SUPERFICIAL MYCOSESSUPERFICIAL MYCOSES

��DermatophytosisDermatophytosis��Pityriasis versicolor Pityriasis versicolor ��KeratomycosisKeratomycosis��KeratomycosisKeratomycosis��Tinea nigraTinea nigra��Black piedraBlack piedra��White piedraWhite piedra

DERMATOPHYTOSISDERMATOPHYTOSIS(=Tinea = Ringworm)(=Tinea = Ringworm)

•• 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 dermatophytesfungi, called dermatophytesfungi, called dermatophytes

¨̈MicrosporumMicrosporum Hair, skinHair, skin¨̈EpidermophytonEpidermophyton Skin, nailSkin, nail¨̈TrichophytonTrichophyton Hair, skin, nailHair, skin, nail

Trichophyton Trichophyton (19 species)(19 species)

•• Hair Hair •• Hair Hair

•• SkinSkin

•• NailsNails

MicrosporumMicrosporum(13 species)(13 species)

•• SkinSkin

•• HairHair

Epidermophyton floccosumEpidermophyton floccosum

•• SkinSkin•• SkinSkin

•• NailsNails

oo DermatophytosisDermatophytosis -- "ringworm" disease of the "ringworm" disease of the nails, hair, and/or stratum corneum of the skin nails, hair, and/or stratum corneum of the skin caused by fungi called dermatophytes. caused by fungi called dermatophytes.

oo DermatomycosisDermatomycosis -- more general name for more general name for any skin disease caused by a fungus. any skin disease caused by a fungus.

THE SKIN PLANTSTHE SKIN PLANTS

•• Dermatophytes are keratinophilic Dermatophytes are keratinophilic -- "keratin "keratin loving".loving". Keratin is a major protein found in Keratin is a major protein found in horns, hooves, nails, hair, and skin. horns, hooves, nails, hair, and skin.

•• Ringworm Ringworm -- disease called ‘herpes' by the disease called ‘herpes' by the Greeks, and by the Romans ‘tinea' (which Greeks, and by the Romans ‘tinea' (which means small insect larvae). means small insect larvae).

Why named as Ringworm lesionWhy named as Ringworm lesion

•• LesionsLesions onon skinskin andand sometimessometimes nailsnails havehaveaa characteristiccharacteristic circularcircular patternpattern thatthat waswasmistakenmistaken byby ancientancient physiciansphysicians asas beingbeing aawormworm downdown inin thethe tissuetissuewormworm downdown inin thethe tissuetissue

•• TheseThese lesionslesions areare stillstill todaytoday calledcalledringwormringworm infectionsinfections eveneven thoughthough thetheetiologyetiology isis knownknown toto bebe aa fungusfungus ratherratherthanthan aa wormworm

Classical “Ringworm” LesionClassical “Ringworm” Lesion

Infections by DermatophytesInfections by Dermatophytes

–– GeophilicGeophilic speciesspecies -- keratinkeratin--utilizingutilizing soilsoilsaprophytessaprophytes (e(e..gg..,,MM.. gypseumgypseum,, TT.. ajelloiajelloi))..

–––– ZoophilicZoophilic speciesspecies-- keratinkeratin--utilizingutilizing onon hostshosts--–– ZoophilicZoophilic speciesspecies-- keratinkeratin--utilizingutilizing onon hostshosts--

livingliving animalsanimals (e(e..gg..,,MM.. caniscanis,, TT.. verrucosumverrucosum))..

–– AnthropophilicAnthropophilic speciesspecies -- keratinkeratin--utilizingutilizing ononhostshosts -- humanshumans (e(e..gg..,,MM.. audouniiaudounii,, TT.. tonsuranstonsurans))

DERMATOPHYTESDERMATOPHYTES

•• Digest keratin by their keratinasesDigest keratin by their keratinases

•• Resistant to cycloheximideResistant to cycloheximide

•• Classified into three groups Classified into three groups •• Classified into three groups Classified into three groups depending on their usual habitatdepending on their usual habitat

DERMATOPHYTESDERMATOPHYTES

•• ANTROPOPHILICANTROPOPHILICTrichophyton rubrum...Trichophyton rubrum...

•• GEOPHILICGEOPHILIC•• GEOPHILICGEOPHILICMicrosporum gypseum...Microsporum gypseum...

•• ZOOPHILICZOOPHILICMicrosporum canisMicrosporum canis: cats and dogs: cats and dogsMicrosporum nanumMicrosporum nanum: swine : swine Trichophyton verrucosum:Trichophyton verrucosum: horse and horse and swine…swine…

DERMATOPHYTOSISDERMATOPHYTOSISPathogenesis and ImmunityPathogenesis and Immunity

•• Contact and traumaContact and trauma

•• MoistureMoisture

•• Crowded living conditionsCrowded living conditions•• Crowded living conditionsCrowded living conditions

•• Cellular immunodeficiency Cellular immunodeficiency ��(chronic inf.)(chronic inf.)

•• ReRe--infection is possible (but, infection is possible (but, larger inoculum is needed, the larger inoculum is needed, the course is shorter )course is shorter )

DERMATOPHYTOSISDERMATOPHYTOSISClinical ClassificationClinical Classification

1.1.Tinea capitisTinea capitis-- ringworm infection of the head, ringworm infection of the head, scalp, eyebrows, eyelashes scalp, eyebrows, eyelashes

2.2.Tinea favosaTinea favosa-- ringworm infection of the scalp ringworm infection of the scalp (crusty hair) (crusty hair)

3.3.Tinea corporisTinea corporis-- ringworm infection of the body ringworm infection of the body 3.3.Tinea corporisTinea corporis-- ringworm infection of the body ringworm infection of the body (smooth skin)(smooth skin)

4.4.Tinea crurisTinea cruris-- ringworm infection of the groin (jock ringworm infection of the groin (jock itch) itch)

5.5.Tinea unguiumTinea unguium-- ringworm infection of the nails ringworm infection of the nails 6.6.Tinea barbaeTinea barbae-- ringworm infection of the beard ringworm infection of the beard 7.7.Tinea manuumTinea manuum-- ringworm infection of the hand ringworm infection of the hand 8.8.Tinea pedisTinea pedis-- ringworm infection of the foot ringworm infection of the foot

(athlete's foot) (athlete's foot)

Tinea CapitisTinea Capitis

Gray Patch

Tinea corporis Tinea corporis –– body ringwormbody ringworm

Tinea Pedis Tinea Pedis –– Athlete’s Foot InfectionAthlete’s Foot Infection

Dermatophytid ReactionDermatophytid Reaction

Tinea Cruris Tinea Cruris –– Jock ItchJock Itch

Tinea Unguium Tinea Unguium –– Nail InfectionNail Infection

Major sources of ringworm Major sources of ringworm infectioninfection

•• Schools,Schools, militarymilitary camps,camps, prisonsprisons..

•• WarmWarm dampdamp areasareas (e(e..gg..,, tropics,tropics, moisturemoisture•• WarmWarm dampdamp areasareas (e(e..gg..,, tropics,tropics, moisturemoistureaccumulationaccumulation inin clothingclothing andand shoes)shoes)..

•• AnimalsAnimals (e(e..gg..,, dogs,dogs, cats,cats, cattle,cattle, poultry,poultry,etcetc..))..

Lab Diagnosis of DermatophytesLab Diagnosis of Dermatophytes

DirectDirect M/EM/E

TreatingTreating skinskin andand nailnail scrapingsscrapings andand “snippets”“snippets” ofofhairhair withwith 1010--2020%% potassiumpotassium hydroxidehydroxide (KOH(KOHdissolvesdissolves keratinkeratin butbut notnot chitinchitin -- hyphae)hyphae) isisusuallyusually veryvery effectiveeffective inin detectingdetecting dermatophytedermatophyteusuallyusually veryvery effectiveeffective inin detectingdetecting dermatophytedermatophytehyphaehyphae inin clinicalclinical specimensspecimens..

TheThe additionaddition ofof calcofluorcalcofluor whitewhite ((11,,44 polymerpolymerspecificspecific fluorochromefluorochrome dye)dye) andanddimethylsulfoxidedimethylsulfoxide (DMSO)(DMSO) toto thethe KOHKOH andandviewingviewing withwith aa fluorescentfluorescent microscopemicroscope isisrecommendedrecommended....

DERMATOPHYTOSISDERMATOPHYTOSISDiagnosisDiagnosis

I. ClinicalI. Clinical

AppearanceAppearance

Wood lamp (UV, 365 nm) Wood lamp (UV, 365 nm) Wood lamp (UV, 365 nm) Wood lamp (UV, 365 nm)

II. Lab II. Lab

A. Direct microscopic examinationA. Direct microscopic examination

(10(10--25% KOH)25% KOH)

Ectothrix/endothrix/favic hairEctothrix/endothrix/favic hair

Ectothrix and EndothrixEctothrix and Endothrix

Fluorescing hair (under Wood's lamp) is seen in dogs and cats infected with some dermatophytes

DERMATOPHYTOSISDERMATOPHYTOSISDiagnosisDiagnosis

B. CultureB. CultureMycobiotic agar Mycobiotic agar Mycobiotic agar Mycobiotic agar Sabouraud dextrose agar Sabouraud dextrose agar Dermatophytes test agarDermatophytes test agar

DERMATOPHYTESDERMATOPHYTESIdentificationIdentification

A. Colony characteristicsA. Colony characteristicsB. Microscopic morphologyB. Microscopic morphology

MacroconidiumMacroconidium MicroconidiumMicroconidiumMacroconidiumMacroconidium MicroconidiumMicroconidiumMicrosporumMicrosporum--------fusiformfusiform------------------------------(+)(+)EpidermophytonEpidermophyton clavateclavate----------------------------------((--))TrichophytonTrichophyton---- --(few)cylindrical/ (few)cylindrical/ ------ ----(+) (+)

clavate/fusiform single, clavate/fusiform single, in clustersin clusters

Microsporum speciesMicrosporum species

Thick wall, spindle shape, multicellular

Epidermophyton floccosumEpidermophyton floccosum

Bifurcated hyphae with multiple, smooth, club shaped macroconidia (2-4 cells)

Trichophyton speciesTrichophyton species

Large, smooth, thin wall, septate, pencil-shaped

DERMATOPHYTESDERMATOPHYTESIdentificationIdentification

C. Physiological testsC. Physiological tests•• In vitro hair perforation testIn vitro hair perforation test•• Special amino acid and vitamin Special amino acid and vitamin •• Special amino acid and vitamin Special amino acid and vitamin

requirementsrequirements•• Urea hydrolysisUrea hydrolysis•• Growth on BCPGrowth on BCP--milk solidsmilk solids--glucose glucose

mediummedium•• Growth on polished rice grainsGrowth on polished rice grains•• Temperature tolerance and enhancementTemperature tolerance and enhancement

DERMATOPHYTOSISDERMATOPHYTOSISTreatmentTreatment

•• Topical Topical Miconazole, clotrimazole, Miconazole, clotrimazole, econazole, terbinafine...econazole, terbinafine...econazole, terbinafine...econazole, terbinafine...

•• OralOralGriseofulvinGriseofulvinKetaconazoleKetaconazoleItraconazoleItraconazoleTerbinafineTerbinafine

PITYRIASIS VERSICOLORPITYRIASIS VERSICOLOR

•• Superficial chronic infection of Superficial chronic infection of Stratum corneumStratum corneum

•• Etio:Etio: Malassezia furfur Malassezia furfur •• Etio:Etio: Malassezia furfur Malassezia furfur (Pityrosporum orbiculare)(Pityrosporum orbiculare)(Lipophilic yeast)(Lipophilic yeast)

•• Clinical findings:Clinical findings: Hyperpigmented Hyperpigmented or depigmented maculae on chest, or depigmented maculae on chest, back, arms, abdomenback, arms, abdomen

PITYRIASIS VERSICOLORPITYRIASIS VERSICOLOR

•• Systemic infection (parenteral Systemic infection (parenteral lipid solution)lipid solution)

•• Micr.:Micr.: Short hyphae, yeast cellsShort hyphae, yeast cells•• Micr.:Micr.: Short hyphae, yeast cellsShort hyphae, yeast cells•• Culture:Culture: Yeast (suppl.: olive oil)Yeast (suppl.: olive oil)•• Treatm.:Treatm.: Topical selenium Topical selenium

sulfidesulfideOral ketaconazoleOral ketaconazoleOral itraconazoleOral itraconazole

KERATOMYCOSISKERATOMYCOSIS(=Mycotic keratitis)(=Mycotic keratitis)

•• Posttraumatic / postsurgical Posttraumatic / postsurgical corneal inf. corneal inf.

•• Etio:Etio: Saprophytic fungi Saprophytic fungi •• Etio:Etio: Saprophytic fungi Saprophytic fungi ((AspergillusAspergillus, , Fusarium, Fusarium, Alternaria, Candida), Histoplasma Alternaria, Candida), Histoplasma capsulatumcapsulatum

•• Clinical findings:Clinical findings: Corneal ulcerCorneal ulcer

KERATOMYCOSISKERATOMYCOSIS

•• Micr.: Micr.: Hyphae in corneal Hyphae in corneal scrapingsscrapings

•• Treatm.: Treatm.: Surgery (keratoplasty)Surgery (keratoplasty)•• Treatm.: Treatm.: Surgery (keratoplasty)Surgery (keratoplasty)

Topical pimaricinTopical pimaricin

NystatinNystatin

Amphotericin BAmphotericin B

TINEA NIGRATINEA NIGRA

•• Superficial chronic infection of Superficial chronic infection of Stratum corneumStratum corneum

•• Etio:Etio: HortaeHortae (Exophiala) werneckii (Exophiala) werneckii •• Etio:Etio: HortaeHortae (Exophiala) werneckii (Exophiala) werneckii (pigmented)(pigmented)

•• Frequent in tropical areasFrequent in tropical areas

•• Clinical findings: Clinical findings: Brownish maculae Brownish maculae on palms, fingers, faceon 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 coloniesBlack colonies•• Culture:Culture: Black coloniesBlack 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

•••• 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)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, axillary Fungal infection of facial, axillary or genital hairor genital hair

•• Etio:Etio: Trichosporon Trichosporon (yeast)(yeast)•• 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 hairattached to the hairattached to the hair

•• Micr.: Micr.: Intertwined septate Intertwined septate

hyphae, blastohyphae, blasto-- and arthroconidiaand arthroconidia

•• Culture:Culture: Soft, creamy coloniesSoft, creamy colonies

•• Treatm.:Treatm.: Shaving, azolesShaving, azoles