Superficial Fungal

Infections

By

Mengistu Hiletework ( M.D.)

Consultant

Dermatovenereologist

Introduction

• Epidemiology

• Sources of infection

Anthropophilic

Zoophilic

Geophilic

Key features

•Cutaneous fungal infections are broadly divided into those

that are limited to the stratum corneum, hair and nails, and

those that involve the dermis and subcutaneous tissues

•Superficial fungal infections of the skin are due primarily to

dermatophytes and Candida species.

•Systemic or 'deep' mycoses of the skin usually represent

hematogenous spread or extension from underlying

structures.

•In the immunocompromised host, opportunistic fungi, e.g.

Aspergillus and Mucor, can lead to both cutaneous and

systemic infections.

•The superficial mycoses are due to fungi that

only invade fully keratinized tissues, i.e. stratum

corneum, hair and nails.

•The superficial mycoses can be further

subdivided into those that induce minimal, if

any, inflammatory response,e.g. pityriasis

(tinea) versicolor, and those that do lead to

cutaneous inflammation, e.g.dermatophytoses

Dermatophytes

and

Dermatophytosis

What are they?

What do they look like?

Genera of dermatophytes

• Epidermophyton

• Trichophyton

• Microsporum

Types of dermatophytosis

• Tinea corporis

• Tinea faciei

• Tinea barbae

• Tinea cruris

• Tinea of hand and feet

• Tinea capitis

• Onychomycosis

• Fungal folliculitis( Majocchi granuloma)

• Tinea incognito

• Dermatophytids

Susceptibility Factors

• Primary immunodeficency syndromes

• Acquired Immunodeficency syndrome

(AIDS)

• Connective tissue disease

• Cancer chemotherapy

• Defective cutaneous barrier ; eg.ichtyosis

• Use of topical corticosteroids

Susceptibility Contd……

• Occlusion

• Genetic susceptibility for certain forms of

fungal infections

Tinea corporis(TC)

• All superficial dermatophyte infections of the skin other

than those involving the scalp, beard, face, hands, feet

and groin. eg.Tinea gladiatorum

• Progressive central clearing, hence ringworm.

• in some cases concentric or polyciclic

Tinea corporis Cont…. Diagnosis

Skin scraping and then Potassium hydroxide

(KOH) mount or Culture

Tinea corporis, Cont…. Treatment

• Topical therapy

Clotrimazole,Miconazole,ketoconazole, Sulconazole,Oxiconazole,Econazole,Terbinafine between two-four weeks, usually twice a day.

• Systemic antifungal treatment

for extensive disease or fungal folliculitis

Griseofulvin, 500-1000 mg/day for 4-6 weeks and for children 10-20 mg/kg/day

Terbinafine, 250mg/day; 1-2 weeks

Itraconazole ;200mg/day for one week

Fluconazole; 150 mg once a week for 4 weeks

Tinea corporis Contd…. Differential Diagnosis

• Pityriasis rosea

• Impetigo

• Nummular dermatitis

• Secondary and tertiary syphilids

• Seborrheic dermatitis

• Psoriasis

Tinea faciei

• Typical annular rings are usually lacking

• Lesions are photosensitive

• A misdiagnosis of lupus erythematosus is

often made

• For fungal folliculitis→oral medication

• If no folliculitis→topical therapy

Tinea barbae

• Tinea mycosis or barber’s itch

• Mostly one sided and chiefly among those

in contact with farm animals

• Two types; deep, nodular suppurative

lesions and superficial crusted, partially

bald patches with folliculitis

Tinea barbae, Cont….

• D/Dg :-

Staphylococcal folliculutis ( Sycosis

vulgaris)

Herpetic infections

• Treatment:-

Oral antifungal agents, and topical agents

are only helpful as adjunctive therapy

Tinea cruris

• Also known as jock itch and crotch itch

• Upper and inner surface of thighs,

especially during the summer when the

humidity is high

• Scrotum rarely involved

Tinea cruris Cont….

• Usually moist, more inflammatory and associated with satellite macules.

• Candida often produces collarette scales and satellite pustules.

D/Dg: -

Erythrasma

Seborrheic dermatitis

Pemphigus vegetans

Intertriginous psoriasis

Tinea of hand and feet

• Athlet’s foot is the most common fungal

disease

• T.rubrum causes the majority of infections;

may be an autosomal –dominant

predisposition to this form

Types of Tinea pedis

• Three Types of Tinea pedis:-

1)Multinocular bullae involving the thin skin of the plantar arch and along the sides of the feet and heel

2)Erythrasma and desquamation between the toes

3)Relatively non inflammatory type characterized by a

dull erythema and pronounced silvery scaling that may

involve the entire sole and sides of the feet( T. rubrum)

Hand may also be involved.

Treatment

• Reduction of perspiration and enhance-

ment of evaporation from the crural area

• Keep as dry as possible by wearing loose

kept clothing

• Specific topical and oral treatment, same

as described for tinea corporis

Tinea palmaris

Tinea pedis

Tinea pedis, D/Dg…

• Simple maceration caused by a closed

web space

• Gram negative toe-web infection

Diagnosis of Tinea pedis/

palmaris • Skin scrapings

• Bullae should be unroofed and either the entire roof mounted intact or scrapings made from the underside of the roof

• Sabouraud dextrose agar, Sabouraud agar with chloramphenicol,mycosel agar,or DTM(dermatophyte test medium)

• Chloramphenicol, mycosel agar,or DTM inhibit growth of bacteria or saprophyte contaminants.

• Mycosel agar and DTM may inhibit some pathogenic nondermatophytes.

• The alkaline metabolites produced by growth of dermatophytes change the color of the PH indicator in DTM medium from yellow to red.

Tinea pedis,Treatment

• Clotrimazole,miconazole,oxiconazole,econazole,ketoconazole,

terbinafine

• Toes separated by foam or cotton inserts, when maceration between toes

• Topical antibiotics like gentamycin against gram- negative organisms in some moist interdigital lesions.

In ulcerative types systemic antibiotics

• Fungal infections of the hands and feet with systemic griseofulvin, terbinafine, itraconazole and fluconazole with a similar regimen to tinea corporis

Tinea pedis Cont…

• Prophylaxis:

1) Since hyperhidrosis is a predisposition factor for tinea infections, toes should be thorougly dried after bathing.

2)Antiseptic powders after bathing, e.g.. plain talc, corn starch, rice powder dusted into socks and shoes to keep the feet dry.

Tinea capitis

• By all pathogenic dermatophytes except

for Epidermophyton floccosum and

Trichophyton concentricum

• Pet exposure→M.canis

• Children can be carriers and still

asymptomatic

Tinea capitis cont…Types

• Seborrheic like scaling.

• Inflammatory kerion.

• Favus.

Diagnosis

• From a highly inflammatory plaque two or three loose hairs are carefully removed with epilating forceps

• Hairs are placed on a slide covered with a drop of 10% to 20% KOH solution.

• Culture with Sabouraud dextrose agar with chloramphenicol

• Diagnosis is made by the gross appearance of the culture growth, together with the microscopic appearance

Tinea capitis, cont….

Differential Diagnosis

• Chronic staphylococcal folliculitis

• Pediculosis capitis

• Psoriasis

• Seborrheic dermatitis

• Secondary syphilis

• Alopecia areata

• Lupus eryrhematosus

• Lichen planus

Tinea capitis,…Treatment

• Griseofulvin tablets; griseofulvin V oral suspension is less readily absorbed

• Fluconazole, 6mg/kg/day for 2-3 weeks

• Terbinafine

• Itraconazole, 5mg/kg/day for 2-3 weeks

• Without medication there is spontaneous clearing at about the age of 15, except with T. Tonsurans , which often persists in adult life.

Onychomycosis

• Infection of the nail plate

• T.rubrum accounts for most cases, but

many fungi like E.floccosum and various

species of Microsporum and Trichophyton

fungi, yeasts and nondermatophyte molds

Types of Onychomycosis

• Distal subungal onychomycosis

• White superficial onychomycosis( Leukonychia trichophytica):

An invasion of the toenail plate in the surface of the nail. Caused by T.mentagrophytes, species of Cephalosporium, and Aspergillus,and Fusarium oxysporum fungi. In the HIV positive population, commonly by T.rubrum

• Proximal subungal onychomycosis; may be an indicaton of HIV.( byT.rubrum and T. megninii)

• Candida onychomycosis. It produces destruction of the nail and massive nailbed hyperkeratosis and is seen in patients with chronic mucocutaneous candidiasis.

Onychomycosis, Cont….D/Dg

• Psoriasis

• Lichen planus

• Eczema

• Contact dermatitis

• Hyperkeratotic/( Norwegian) scabies

Onychmycosis Treatment

• Griseofulvin

• Terbinafine, for finger nails 250mg/day for 6-8 weeks, for toe nails 12-16 week

• Itraconazole, pulse therapy of 200 mg twice a day for 1 week of each month, for 2-3 months when treating finger nails, and for 3-4 months when treating toe nails

• Fluconazole, 150-300mg/once a week for 6-12 months

Onychomycosis, Cont….

Diagnosis

• Microscopic examination

• Culture

• Histopathologic examination with a

periodic acid –Schiff stain(PAS),41-93%

sensitive. More sensitive than either KOH

or culture

Onycho. Treatment cont….

• Presence of dermatophytoma,presenting as yellow

streaks within the nail, may be associated with a higher risk of failure

• Candida onychomycosis is always a sign of immunosuppression. Combinations of topical and systemic treatment can be used for synergistic effect.

• Molds are sensitive to ultraviolet(UV) and visible light

• Nystatin, topical amphotericin B lotion

Older agents such as gentian violet, castellani paint, boric acid

Oral candidiasis( Thrush)

• In the newborn may be acquired from contact with the vaginal tract of the mother

• In older children and adults , following antibiotic therapy it may also be a sign of immunosuppression

• Grayish-white membranous plaques with moist,reddish,and macerated base

• The papillae of the tongue may appear atrophic, with the surface smooth, glazed, and bright red.

• Saliva inhibits the growth of Candida, and a dry mouth predisposes to candidial growth.

Treatment of oral Candidiasis

• Infants : oral nystatin suspension

• Adults: A single dose of 150 mg.

fluconazole

• Immunocompromised adults:200 mg. is

the starting dose, or higher dose.

• Itraconazole,200mg./day for 5-10 days

• Terbinafine,250 mg./day

Perle’che( angular cheilitis)

• Characterized by maceration and transverse fissuring of the oral commissures.

• Soft pin-head sized papules may appear

• Usually bilateral

• Commonly related to C.albicans, but may also harbour coagulase-positive S.aureus and gram-negative bacteria

• Similar changes may occur in riboflavin deficency or other nutritional deficiency, and from drooling in persons with malocclusion caused by ill-fitting dentures, and old age when the upper lip overhangs the lower at the commissures.

• If the cause is C.albicans, anticandidal creams

Candidal vulvovaginitis

• C.albicans is a common inhabitant of vaginal tract. Overgrowth can cause severe pruritis,burning and discharge.

• Discharge varies from watery to thick and white or curd like.

• Predisposing factors:

pregnancy, diabetes, secondary to

therapy with broad-spectrum antibiotics

Candida vulvovaginitis,…Cont.

Treatment

• Oral fluconazole, 150 mg given once.

• In some patients with predisposing factor

longer courses of 150-200 mg/day or itraconazole, 200 mg/day for 5-10 days.

• Topical options: miconazole,nystatin,clotrimazole, and terconazole

Candidal Intertrigo

• Between the folds of the genitals; in groins

or armpits; between the buttocks; under

large pendulous breasts; under

overhanging abdominal folds; or in the

umbilicus

• Often ,tiny, superficial, white pustules

closely adjacent to the patches

Diaper Candidiasis

• Involvement of the folds and occurrence of many small erythematous desquamating “satellite” scattered along the edge of the larger macules.

• Eythematous macules progress to thin-walled pustules, which rupture, dry, and desquamate within a week or so.

• Usually widespread involving the trunk, neck, and head, and at times the palm and soles, including the nail folds.

• Oral cavity and diaper are spared.

• Systemic involvement may occur, and more common in infants who weigh<1500gm.

• Systemic involvement is suspected when respiratory distress or other laboratory or clinical signs of neonatal sepsis occur

Perianal Candidiasis

• May present as pruritis ani.

• Perianal dermatitis with erythema,oozing,

and maceration

• Satellite lesions may be present

Candidial paronychia

• Inflammation of the nail fold producing redness,

edema, and tenderness of the proximal nail

folds, and gradual thickening and brownish

discoloration of the nail plates.

• Acute paronychia is usually staphylococcal in

origin.

• Avoidance of irritants and wet work is essential.

• Treatment is anticandidial agents alone or in

combination with topical corticosteroid.

Erosio Interdigitalis

Blastomycetica

• An oval- shaped area of macerated white skin seen in the web b/n and extending onto the sides of the fingers.

• Nearly always the third web, between the middle and ring fingers. The moisture beneath the ring macerates the skin and predisposes to infection.

• On the feet, the fourth interspace that is most often involved.

Chronic Mucocutaneous

Candidiasis

• A chronic candidial infection of the

mucosal surfaces, skin, and nails.

• Onset , typically before age of six.

• Onset in adult life may herald the

occurrence of thymoma.

Chronic Mucocutaneous

Candidiasis, …cont.

• Either inherited or sporadic.

• Inherited type may be associated with endocrinopathy.

• Patients with this problem have a selective defect in immunity that leaves them vulnerable to candidiasis.

• The underlying defect is unknown.

• Control: systemic fluconazole, itraconazole,or ketoconazole

Candid

As in dermatophytosis, patients with

candidiasis may develop secondary id

reaction.

Dermatophytids

• “id” eruptions concomitantly on the trunk and extremities; vesicular, lichenoid, papulosquamous,or pustular.Rarely scarlatinform or morbilliform

• Fungus not demonstrable

• Erysepelas like dermatophytid is most commonly seen on the shin, usually with toe web tinea on the same side.

• As the fungal infection subsides involution of the dermatophytids.

Fungal Folliculitis( Majocchi

granuloma)

• Presents as a circumscribed , annular,

raised, crusty and boggy granuloma in

which the follicles are distended with viscid

purulent material.

• Most frequently on the shins or wrists.

Often in areas of occlusion, shaving or

when topical corticosteroid has been used

Tinea incognito

Atypical clinical lesions of tinea, usually

produced by treatment with a topical

corticosteroid or occasionally a calcineurin

inhibitor.

Tinea versicolor ( Pityriasis

versicolor) • Caused by Malassezia furfur. The yeast form of this

organism is classified as Pityrosporum orbiculare.

• As a yeast the organism is a normal follicular flora.

• It produces skin lesions when it grows in the hyphal phase.

• Hyper-or hypopigmented coalescing scaly macules on the trunk and upper arms.

• In some instances many follicular papules.

• Pink, atrophic, and trichome variants exist. May occur on the penis, pubis, scalp,and palms.

Tinea versicolor,….Cont.

Diagnosis • Scrapings of the scales

• Tape stripping of the lesions

• Microscopically, short, thick fungal hyphae and large number of variously sized spores( spaghetti and meat balls)

• Biopsy: a thick basket-weave stratum corneum with hyphae and spores.

• In the atrophic variant, epidermal colonization with hyphae and spores is accompanied by effacement of the rete ridges, subepidermal fibroplasia, pigment incontinence, and elastolysis

• Wood’s light examination accentuates pigment changes (yellow-green fluoresence of the lesions)

• Rarely culture

T. versicolor, cont…D/Dg.

• Seborrheic dermatitis

• Pityriasis rosea

• Pityriasis rubra pilaris

• Pityriasis alba

• Leprosy

• Syphilis

• Vitiligo

T. versicolor, Cont….

In the atrophic variant, parapsoriasis,

mycosis fungicides, anetoderma, lupus

erythematodes, or steroid atrophy

Treatment of T. versicolor

• Imidazole, triazole, selenium sulfide, ciclopirox olamine, zinc pyrithione, sulfur preparations, salicylic acid preparations, benzoyl peroxide

• Selenium sulfide, applied daily for a week, washed off after 10 minutes. Also as a single overnight application, repeated monthly as prophylaxis

• Ketoconazole, 400 mg., repeated monthly

• Itraconazole, 200 mg. once a day for 7 days, followed by a prophylactic treatment with 200 mg. twice a day on first day of a month.

• Fluconazole, 400 mg. once, and repeated at monthly intervals.

• Terbinafine is ineffective via the oral route, but effective topically.

Pityrosporium folliculitis

Criteria for diagnosis include:-

• Characteristic morphology,

• Demonstration of yellow-green wood’s

light flurosenceof the papules

• Demonstration of pityrosporum yeast in

smears or biopsies

• Prompt response to antifungal treatment