FUNGAL INFECTION-DERMATOPHYTOSIS/TINEA

DERMATOPHYTOSIS(“TINEA”)

📍Superficial fungal infection of keratinized tissue  by keratinophillic fungi called dermatophytes

📍Invade hair, nails and skin but not deeper tissues

📍Classified into three genera:
1)Trichophyton - infections of skin, hair, and nails
2)Microsporum - infections of skin and hair
3)Epidermophyton - infections on skin and nails

📍According to anatomic location involved
T. capitis
T. barbae
T. faciei
T. corporis
T. cruris
T. manuum
T. pedis
T. unguium

TINEA CAPITIS

📍Affect scalp hair follicles and intervening skin

📍Prepubertal children affected more due to the absence of sebum
   (fatty acids : fungistatic)

📍Species involved are:
  M. canis
  T. tonsurans
  T. violaceum
  T. rubrum

📍Classified according to the size and the location of the spore:-

1. Ectothrix (spores outside the hair shaft) 
 Infected hairs appear dull and gray
  - fluorescent small spore :M. audouinii and M. canis
  - Nonfluorescent large spore:T. mentagrophytes and T. rubrum

2. Endothrix (spores inside the hair shaft):-  
   - Hairs break at the follicular orifice 
   - patches of alopecia with “BLACK DOT” of broken hairs
   - T. tonsurans and T. violaceum cause this

📍 PATHOGENESIS OF TINEA CAPITIS:-

*Ectothrix infection begins at the perifollicular stratum corneum >>>>>descends down to reach the mid-follicle hyphae>>>> descend within the intrapilary region towards the keratinous zone>>>>>divide into arthrospores>>>>reach the cortex 
Infection is confined to the hair surface beneath the cuticle

*Endothrix Infection
Arthrospores replace much of the intrapilary keratin while leaving the cortex intact

📍KERION

*Most severe inflammatory type
*T. verrucosum or T. mentagrophytes
*inflamed boggy and indurated tender swelling that is studded with broken or unbroken hairs, vesicles, and pustules
*mostly heals with scarring
*lymphadenopathy
*Secondary bacterial infection 

📍FAVUS

*T. schoenleinii 
*chronic inflammatory type 
*a yellow cup-shaped crust with central depression
*scutulum due to its shield-like shape
*concavity of this cup faces upward and is pierced by a hair
*As the infection progresses, the scutulae enlarge and merge to form yellowish crusts with a central healing with scar
*cicatricial alopecia
*mousy odor

📍GREY PATCH

*M. audouinii
*Small erythematous papules that surround the hair shafts
*asymptomatic
*spreads centrifugally
*patches of partial hair loss : dull gray & lustureless 
*fine scaling 

📍BLACK DOTS

*Trichophyton tonsurans and Trichophyton violaceum
*The hair shaft is extremely brittle and breaks at the level of scalp
*follicle appears as a black dot
*diffuse scaling with minimal hair loss or inflammation

📍How will you diagnose Tinea capitis?

*Wood’s lamp: 
Bright green fluoresence is seen in ectothrix – M.audouinii
Dull green fluoresence is seen in favus – T.schoenleini

*KOH mount- distinguish ectothrix and endothrix

*Dermoscopy -comma hair, cork screw hair, zigzag hair

TINEA   BARBAE

📍Synonyms: 
  Barber's itch
  Tinea sycosis

📍hair follicles of the beard and moustache

📍T.mentagrophytes& T. verrucosum

📍least common type

📍pathogenesis is the same as that of tinea capitis

TINEA   FACIEI

📍nonbearded skin of the face

📍T.rubrum and T.mentagrophytes

📍Clinical Features –
 Erythematous, scaly macule that extends peripherally develops an annular plaque with raised borders

📍Pinna is frequently involved

📍TYPES – Circinate, Arcuate, Annular plaques with raised margins

TINEA   CORPORIS

📍glabrous skin affected with the exclusion of the palms ,soles ,face and groins 

📍most common form 

📍The most common : T. mentagrophytes and T.rubrum

📍invades the stratum corneum

📍Active advancing border has increased epidermal turnover rate to shed the organism by exceeding the fungal growth rate

📍Fungal mannans in the dermatophyte cell wall act against local immunity

📍Annular or polycyclic

📍Erythematous and vesicular or scaly, but the center is clear 

📍Inflammatory lesions : pustules and vesicles 

📍Non inflammatory : scaling 

📍Central skin : postinflammatory hyperpigmentation 

📍Any area of the body

TINEA   CRURIS

📍Superficial dermatophytic infection of the groin and adjacent skin  males 

📍"Dhobi's itch" or "jock itch"

📍high environmental temperature and sweating,mechanical irritation of apposed surfaces,decreased aeration are the triggers

📍T. rubrum, T. indotineae T. interdigitale & E.floccossum

📍Genitocrural area and adjoining inner thighs affected;
bilateral and asymmetrical, coalesce and spread to involve the buttocks, the lower back and the abdomen

📍Lichenification due to constant scratching 

📍Secondary bacterial infection can happen

📍Severe local inflammation with oozing and maceration can happen

TINEA PEDIS

📍Dermatophyte infection of the soles of the feet and the interdigital spaces

📍“Athlete's foot"

📍hands and feet : favourable environment 
 Why? lack of sebum : inhibitory to dermatophyte proliferation

📍Mostly affects-web space between 4th and 5th toes followed by 3rd and 4th toe
summer, warm and humid conditions 

📍At risk-people who wear occlusive shoes

📍 coexist with onychomycosis

📍Caused by:-

 T.rubrum
 T.interdigitale

📍VARIANTS OF TINEA PEDIS

1)INTERDIGITAL TYPE 
*scaling, fissuring or maceration
*May spread to sole or instep of foot
*The lateral toe webs(3rd and 4th ) are common sites
*Aggravating factors are warmth, humidity and hyperhydrosis

2)CHRONIC HYPERKERATOTIC TYPE
(  MOCCASIN FOOT)
•inflammation and a patchy or diffuse moccasin-like scaling over the soles, heels, and sides of the feet
•hands & multiple toenails
•"one-hand two-feet" presentation
HPE : hyperkeratosis and acanthosis

3)VESICULAR (INFLAMMATORY, BULLOUS) TYPE 
*T. interdigitale
*small vesicles or vesiculopustules near the instep 
*associated with scaling in these areas & toe webs
HPE: intraepidermal spongiotic vesicles 

4)ACUTE ULCERATIVE TYPE
•rapidly spreading vesiculopustular lesions, weepingand ulceration
•white hyperkeratosis and pungent odour
secondary bacterial infection can happen

TINEA MANUUM

📍Dermatophytosis of palmar skin

📍males more affected

📍T.rubrum

TINEA UNGUIUM AND ONYCHOMYCOSIS 

📍Onychomycosis : all infection of nail caused by any fungus including dermatophytes, non dermatophytes, mold and yeasts

📍Tinea unguium : dermatophytic infection of nail

📍Associated with T.pedis and T.mannum

📍Mostly seen in males

📍toenails more than finger nails

📍Risk factors-old age, trauma to nail, poor peripheral circulation, smoking, hyperhydrosis

📍TYPES OF ONYCHOMYCOSIS 

1)Distal and lateral subungual onychomycosis (DLSO)
*most common pattern 
*streak or a patch of white or yellow discolouration
*at the free edge of the nail plate and near the lateral nail fold 

2)Superficial onychomycosis (SO)
*less common 
*dorsal surface of the nail plate is eroded
*well-circumscribed, powdery white patches
*as transverse linear streaks away from the free edge 

3)Proximal subungual onychomycosis
*associated with immunosuppression including AIDS
*Rapid invasion of the nail plate from the posterior nail fold
*white nail with only a marginal increase in thickness
*linear bands or patches emerging from under the proximal nail fold 

4)Endonyx onychomycosis
*dermatophytes that cause endothrix scalp infections
*T. Soudanense
*nail plate is scarred with pits and lamellar splits
*invasion occurs from the top surface but penetrates deeply into the nail plate 

5)TOTAL DYSTROPHIC ONYCHOMYCOSIS
*most severe and final stage of onychomycosis
*The nail plate is diffusely thickened, friable and discolored
*due to longstanding or untreated DLSO or PSO

SPECIAL ENTITIES:-

•Tinea imbricata
•Tinea incognito
•Majocchi granuloma
•T.rubrum syndrome
•Deep dermatophytosis
•Two feet one hand syndrome
•Onychophytoma
*Dermatophytids

TINEA IMBRICATA

📍Large concentric scaly plaques that overlap to produce the lamellar form

📍T. concentricum

📍Intense pruritus

📍lichenification

TINEA INCOGNITO

📍lost its typical clinical appearance

📍Due to use of topical / systemic immunosuppressants- STEROIDS OR CALCINEURIN INHIBITORS
  📍render them almost unrecognizable

📍Immunosuppression : suppression of inflammation
     modified clinical appearance,transforming the typical lesions,mimicking other skin diseases

📍difficulty in diagnosis and wrong treatment

📍pruritus is reduced

📍raised margin.s are diminished

📍scaling is lost

📍erythema is reduced

📍With chronic use of topical corticosteroids, local side effects like striae, atrophy and telangiectasia become obvious

TINEA PSEUDOIMBRICATA 

 📍Concentric rings of erythema

 T. mentagrophytes
 T. rubrum

MAJOCCHI GRANULOMA

📍Other names : 
 Granuloma trichophyticum 
 Nodular granulomatous perifolliculitis

📍Most common: T. rubrum 

📍Dermatophytes usually do not invade beyond the epidermis
 Mechanical breakage of the skin resulting from scratching/trauma and immunocompromised state allow penetration of the fungi into the reticular dermis

📍Extensive granulomas
chronic, nonpruritic, solitary / multiple papulopustules or plaques
over the legs

📍Two clinical forms : the follicular type & the subcutaneous nodular type 
*Follicular type : secondary to trauma 
       not associated with immunosuppression
       young women who repeatedly shave their legs
*Subcutaneous nodular type : in immunocompromised hosts 
       Hair-bearing areas like scalp, face, forearms and legs

TRICHOPHYTON SYNDROME

📍Diagnosed with clinical and mycological criteria

1) Skin lesions at the four sites: 

 A) feet , often involving soles
 B) hands, often involving palms
 C) nails
 D) at least one more site other than groins

2) Positive microscopic analyses / KOH preparations of skin scrapings in all four locations

2-FEET 1-HAND SYNDROME

*Bilateral tinea pedis and unilateral tinea manuum occurring simultaneously
often with onychomycosis
*Tinea pedis/onychomycosis generally precedes the development of tinea manuum

DERMATOPHYTOMA

*circumscribed dense fungal masses in the nail plate
*linear, single or few white or yellow bands on the nail plate forming a biofilm
*decreased antifungal penetration 
*resistant to standard antifungal therapy
*necessitates surgical intervention



👉Recurrent dermatophytosis : 

Re-occurrence of the dermatophyte infection after clinical cure within few weeks of completion of the treatment

👉Recalcitrant dermatophytosis : 

 relapse, recurrence, reinfection, persistence and microbiological resistance

👉Chronic dermatophytosis: 

Dermatophytosis for more than 6 months duration, with or without recurrence, in spite of having taken treatment

📌MANAGEMENT   OF   DERMATOPHYTOSIS

📍General measures

*Avoid sharing of garments & towels, including bathroom napkins 

*All the garments must be thoroughly washed daily in hot water and sun-dried

    (Iron-pressed reverse if sun drying is not feasible)

*Wear loose fitting cotton garments

*Tight-fitting jeans are avoided

 *Avoidance or minimization of close contact with child or spouse until adequate treatment is taken

*Avoidance of body-contact sports and swimming 

* treatment of affected family members 

*Examination of nails and feet to rule out reservoirs of infection 

*Explained to the patient that application of steroids suppresses the inflammation but does not reduce the proliferation of the organisms

*Keep the skin dry

*Twice daily bathing if the patient tends to sweat a lot

📍Topical therapy 

Topical antifungals

*Azoles 

 - inhibit the biosynthesis of ergosterol

 - first line topical agents 

 - effective and low incidence of side effects

 eg: miconazole, clotrimazole, ketoconazole, oxiconazole, sertaconazole, luliconazole, eberconazole

Luliconazole : currently preferred topical agent with excellent effectiveness against filamentous fungi including dermatophytes



*Butenafine and terbinafine 

  recently discovered resistance to this group of molecules

*Hydroxypyridilones 

 Ciclopirox 1% cream better than clotrimazole 1% cream

*Use of antifungal soaps :-

 lacking in scientific logic & an additional financial burden

   - expected contact time and ultimate concentration of the preparation do not help achieve adequate levels in the stratum corneum

   - subtherapeutic levels may promote the development of resistance

*Plain dusting powders : in intertriginous infections where sweating is a major challenge to be addressed as in   intertriginous tinea pedis. There should be an adequate gap between the cream and powder

    cream forms a layer

*Methodology of use of topical antifungals 

    (RULE OF 2)

            - should be continued for at least 2 weeks after the clinical resolution of the lesions

            - to be applied on the entire affected area and at least 2 cm outside the lesion circumferentially

           - twice daily application 

📍Systemic antifungal therapy in dermatophytosis

*Indications 

-Failure of topical agent

-Extensive lesions

-Involvement of multiple anatomical sites

-Chronic, recurrent and recalcitrant dermatophytosis

-Involvement of vellus hair and nail

-Steroid modified cases

-Majocchi’s granuloma 

*Choice of systemic antifungals

1)Itraconazole

2)Terbinafine

3)Griseofulvin

4)ketoconazole 

5)Fluconazole

1)ITRACONAZOLE :

* most preferred antifungal in the current scenario due to increasing cases of treatment failure

 *ITRACONAZOLE: the most effective agent followed by fluconazole daily  then terbinafine 

 and   lastly griseofulvin

*dose of 100 mg twice daily  for a minimum duration of 2–4 weeks in new cases

*four weeks in recalcitrant cases

*Investigations like liver function test and an ECG before prescribing especially in elderly patients in those with a history of any hepatic or cardiovascular morbidity like CCF

*gastric acidity is required for absorption 

*should be taken immediately after a full meal

*Acidic beverages (soft drinks) can enhance uptake

*proton-pump inhibitors/ H2-antagonists decrease absorption

2)TERBINAFINE:

 *250 mg twice daily for 2-4 weeks

3)GRISEOFULVIN:

*dose of 10–15 mg/kg body weight in two divided doses for six weeks

4)FLUCONAZOLE:

*advantages : good oral absorption and lower cost

*Weekly regimens : strongly discouraged 

* use of fluconazole 100 mg daily for at least 2–4 weeks beyond clinical clearance is recommended

*even daily dosage does not give satisfactory results in many patients

*recommended to be used only in cases where other molecules cannot be prescribed

 - due to underlying comorbidities

 -obvious contraindications 

 -lactating mothers 

📍Combination therapy of systemic antifungals

- chronic or recalcitrant dermatophytosis with unsatisfactory response at the end of three weeks of conventional therapy 

*  fluconazole/itraconazole + terbinafine

* griseofulvin + terbinafine 

*griseofulvin + fluconazole/itraconazole