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Tinea Infections, Cutaneous, Emergency Medicine

Basics

Description

- Superficial fungal infections of the hair, skin, or nails: - Usually confined to the stratum corneum layer - Among the most common diseases worldwide

- Fungi can be spread from toys and brushes - Tinea unguium is rare in children and is associated with: - Down syndrome - Immunosuppression - Tinea pedis or capitis

- Tinea corporis ( "ringworm " ): - Arms, legs, and trunk - Sharply marginated, annular lesion with raised margins and central clearing - Hair follicle involvement may produce indurated papules and pustules - Lesions may be single, multiple, or concentric - Pets are often a vector

- Tinea cruris ( "jock itch " ): - Erythematous, scaly, marginated patches involving the perineum, thighs, and buttocks - Associated with heat, humidity, and tight-fitting undergarments - Unlike the case in candidiasis, the scrotum and penis are spared

- Tinea pedis ( "athletes foot " ): - Scaling, maceration, fissuring between the toes - Risk factors: - Advanced age - Immunocompromised status - Hot, humid climates - Infrequent changing of socks

- Tinea versicolor (not true tinea): - Most common in warm months - Round or oval superficial brown, yellow, or hypopigmented macules that may coalesce - Upper trunk, arms, and neck - Facial involvement is common in children

- Wood lamp is insensitive: - Trichophyton, the most common cause of tinea infections, does NOT fluoresce - Microsporum fluoresces bright green - Malassezia (tinea versicolor) fluoresces yellow to yellow-green - Erythrasma (nontinea corynebacterial infection) will fluoresce coral red

- Microscopy: - Cleanse area with 70% ethanol - Scrape active margin of lesion with no. 10 or no. 15 scalpel blades - Place scrapings on a glass slide, add a drop of 10 " 20% potassium hydroxide solution, and cover with a coverslip - The presence of septate hyphae confirms dermatophyte infection - Budding yeasts and short hyphae ( "spaghetti and meatballs " ) confirms Malassezia

- Methods to obtain fungal elements for culture or microscopy: - Brushing the hair with a toothbrush - Rolling a moistened cotton swab - Collecting skin cells with transparent tape

- Newer oral antifungals, including terbinafine, itraconazole, and fluconazole, are preferred: - Retained in tissues longer - Allows for shorter treatment courses without a decrease in efficacy - Improved compliance

  • Superficial fungal infections of the hair, skin, or nails:Usually confined to the stratum corneum layerAmong the most common diseases worldwide
  • Requires keratin for growth, so does not involve mucosa
  • Named for location of infection

Etiology

  • Dermatophytes:MicrosporumTrichophytonEpidermophytonMalassezia furfur, a yeast, is the etiologic agent of tinea versicolor (not a true tinea)
  • Trauma or maceration of the skin may allow fungal entry into skin
  • Transmission may be person to person, animal to person, or soil to person
  • Fungi can be spread from toys and brushes
  • Tinea unguium is rare in children and is associated with:Down syndromeImmunosuppressionTinea pedis or capitis

Diagnosis

Signs and Symptoms

  • Tinea capitis:Children are predominately affectedMost contagious dermatophytosisAlopecia, dandruff-like scalingKerion:Boggy, inflammatory mass that exudes pus and causes cervical lymphadenopathy "Black dots " from infected hairs broken off at the scalp
  • Tinea corporis ( "ringworm " ):Arms, legs, and trunkSharply marginated, annular lesion with raised margins and central clearingHair follicle involvement may produce indurated papules and pustulesLesions may be single, multiple, or concentricPets are often a vector
  • Tinea cruris ( "jock itch " ):Erythematous, scaly, marginated patches involving the perineum, thighs, and buttocksAssociated with heat, humidity, and tight-fitting undergarmentsUnlike the case in candidiasis, the scrotum and penis are spared
  • Tinea pedis ( "athletes foot " ):Scaling, maceration, fissuring between the toesRisk factors:Advanced ageImmunocompromised statusHot, humid climatesInfrequent changing of socksMore common in adults than childrenMost common tinea infection in US "Trichophytid " reaction:Vesicular eruption remote from infectionInvolving hands, mimics dyshidrotic eczema
  • Tinea unguium:1 type of onychomycosisYellow or brown discoloration with thickening and debris under the nailsOnycholysis: Loosening of the nail from bedMay involve the plantar surface of the foot
  • Tinea versicolor (not true tinea):Most common in warm monthsRound or oval superficial brown, yellow, or hypopigmented macules that may coalesceUpper trunk, arms, and neckFacial involvement is common in children

History

  • Time of onset from inoculation to visible skin changes is about 2 wk
  • Main symptom is itching:Hair loss with tinea capitis
  • Participation in contact sports or contacts with similar skin disease

Physical Exam

  • Tinea capitis: Alopecia, broken hairs at scalp surface
  • Tinea corporis: Areas of exposed skin typically involved with annular scaly plaques, raised edges, may have pustules and vesicles
  • Tinea cruris: Erythematous lesions on groin and pubic region with central clearing and raised edges
  • Tinea pedis: Scaling, maceration, and fissuring of toe webs, often only 1 foot affected
  • Tinea unguium: Separation of nail plate from nail bed with thickened, discolored, broken nails

Essential Workup

  • Diagnose by clinical exam
  • If diagnosis is in doubt, confirm with microscopy before starting oral antifungals because of possible side effects

Diagnosis Tests & Interpretation

Lab

Fungal cultures are slow growing and should not be routinely done

Imaging

Generally not indicated

Diagnostic Procedures/Surgery

  • Wood lamp is insensitive:Trichophyton, the most common cause of tinea infections, does NOT fluoresceMicrosporum fluoresces bright greenMalassezia (tinea versicolor) fluoresces yellow to yellow-greenErythrasma (nontinea corynebacterial infection) will fluoresce coral red
  • Microscopy:Cleanse area with 70% ethanolScrape active margin of lesion with no. 10 or no. 15 scalpel bladesPlace scrapings on a glass slide, add a drop of 10 " 20% potassium hydroxide solution, and cover with a coverslipThe presence of septate hyphae confirms dermatophyte infectionBudding yeasts and short hyphae ( "spaghetti and meatballs " ) confirms Malassezia
  • Methods to obtain fungal elements for culture or microscopy:Brushing the hair with a toothbrushRolling a moistened cotton swabCollecting skin cells with transparent tape

Differential Diagnosis

  • Tinea capitis: Impetigo, pediculosis, alopecia areata, seborrheic dermatitis, atopic dermatitis, and psoriasis
  • Tinea corporis: Impetigo, herpes simplex, Lyme disease, verruca vulgaris, psoriasis, nummular eczema, granuloma annulare, herald patch of pityriasis rosea, erythema multiforme, urticaria, seborrheic dermatitis, and secondary syphilis
  • Tinea cruris: Impetigo, seborrheic dermatitis, psoriasis, candidal infection, irritant and allergic contact dermatitis, and erythrasma
  • Tinea pedis: Scabies, erythrasma, Candida, allergic and contact dermatitis, and psoriasis
  • Tinea unguium: Psoriasis, dermatitis, lichen planus, and congenital nail dystrophy
  • Tinea versicolor: Vitiligo, secondary syphilis

Treatment

Pre-Hospital

Maintain universal precautions.

Initial Stabilization/Therapy

Only in immunocompromised or septic patients

Ed Treatment/Procedures

  • Improvement usually occurs within 1 " 2 wk of treatment; hair and nail tinea require longer treatment of 3 " 6 mo
  • Topical antifungals do not penetrate hair/nails:Use in conjunction with systemic agent for tinea capitis or unguium.
  • Tinea capitis:Terbinafine is now considered the drug of choice by most:Pill form may be crushed in foodNewer oral antifungals, including terbinafine, itraconazole, and fluconazole, are preferred:Retained in tissues longerAllows for shorter treatment courses without a decrease in efficacyImproved complianceSelenium sulfide or ketoconazole shampoo reduces transmissibilityKerion may respond more rapidly with addition of prednisone (peds: 1 mg/kg PO QD for 2 wk)

Terbinafine may be less effective than griseofulvin against Microsporum species causing tinea capitis; however, Trichophyton species are the predominant causative organism in children:

  • Tinea corporis, cruris, and pedis:Topical terbinafine or imidazoles (ketoconazole, miconazole, and clotrimazole) are 1st-line agents:Topical terbinafine has been shown to be as effective as or more effective than the imidazoles, with a shorter courseOral therapy may be necessary for cases resistant to topical treatment or for immunocompromised patientsKeep the area dry (talc powders) and frequently change socks and underclothes
  • Tinea unguium:Requires oral therapy and longer course than other tinea infectionsTerbinafine had a slightly higher cure rate than imidazoles (ketoconazole, miconazole, and clotrimazole) or griseofulvin in a meta-analysisCiclopirox 8% nail lacquer approved for treatment but has low cure rates:
  • Tinea versicolor:Topicals are 1st-line therapy:Selenium sulfide 2.5% shampoo was as effective as topical ketoconazoleOral ketoconazole, itraconazole, or fluconazole have been used with cure rates up to 97% but are not as safe as topicals

Medication

  • Ciclopirox 8% nail lacquer: Apply to the affected nails daily, max. 48 wk; remove with alcohol every 7 days (peds: Same).
  • Clotrimazole: Apply 1% cream to affected area BID for 4 " 6 wk (peds: Same).
  • Fluconazole: Tinea unguium " 150 " 300 mg/wk pulse therapy for 3 " 6 mo for fingernails, 6 " 12 mo for toenails; tinea corporis, cruris, and pedis: 150 mg PO weekly for 4 " 6 wk; tinea versicolor: 400 mg PO single dose (peds: 6 mg/kg/d for 3 " 6 wk for tinea capitis)
  • Griseofulvin: Tinea capitis, corporis, cruris " 500 mg PO QD for 4 " 6 wk (peds: 10 " 20 mg/kg up to 500 mg PO QD until the hair regrows, usually 6 " 8 wk)
  • Itraconazole: Tinea capitis: Adults and peds: 3 " 5 mg/kg PO QD for 2 " 4 wk; tinea unguium: 200 mg PO QD for 3 mo; tinea versicolor: 400 mg PO QD for 3 " 7 days; contraindicated in CHF
  • Ketoconazole: 2% topical cream QD for 4 " 6 wk; tinea capitis, corporis, cruris, pedis " 200 mg PO QD for 4 wk (peds: 3.3 " 6.6 mg/kg PO QD for 4 wk); tinea versicolor " 400 mg PO 1 or 200 mg QD for 7 days (contraindicated with terfenadine and astemizole); soda increases absorption 65%
  • Miconazole: Apply cream to affected area BID for 4 " 6 wk (peds: Same)
  • Selenium sulfide: 2.5% shampoo to affected area for 10 min for 1 " 2 wk (peds: Same)
  • Terbinafine: 1% topical cream BID for 4 " 6 wk for tinea pedis QD for tinea corporis and tinea cruris; tinea unguium " 250 mg PO QD for 6 wk for fingernails, 12 wk for toenails (peds: <20 kg, 67.5 mg/d; 20 " 40 kg, 125 mg/d; >40 kg, 250 mg/d at same interval as adult); tinea pedis: 250 mg PO per day for 2 wk; tinea capitis: 250 mg/d for 4 wk (dose by weight as for tinea unguium for 4 wk)
  • Tolnaftate: Apply 1% cream/powder/solution to the affected area BID for 4 " 6 wk (peds: Same)
  • The oral antifungals may rarely cause hepatotoxicity; consider checking liver transaminases prior to initiating therapy

Topical preparations are preferred when possible

  • Few studies addressing the use of antifungal medications during pregnancy in humans
  • Some of the imidazoles have shown adverse effects in animals " class C (fluconazole, itraconazole, ketoconazole)
  • Clotrimazole, miconazole, and terbinafine are class B drugs
  • Weigh risk: Benefit as elective antifungal therapy generally not recommended.

First Line

  • Tinea capitis: Terbinafine
  • Tinea corporis, cruris, pedis: Topical terbinafine or imidazoles (ketoconazole, miconazole, and clotrimazole)
  • Tinea versicolor: Selenium sulfide shampoo and topical ketoconazole

Follow-Up

Disposition

Admission Criteria

  • Invasive disease in immunocompromised host
  • Kerion with secondary bacterial infection

Discharge Criteria

  • Most patients may be managed as outpatients
  • Children may return to school once appropriate treatment has been initiated

Issues for Referral

Patients started on oral antifungals should be referred for follow-up to monitor therapy and advised regarding symptoms of hepatitis

Follow-Up Recommendations

  • Monitor for bacterial superinfection, cellulitis, generalized invasive infection:Especially in immunocompromised (diabetics, HIV patients)

Pearls and Pitfalls

  • Tinea capitis is the most common pediatric dermatophyte infection
  • Itching is the main symptom in most forms of tinea, with associated hair loss in tinea capitis
  • Cellulitis frequently complicates of tinea pedis
  • Relapse of tinea pedis/cruris is commonPatients should wash or replace contaminated socks/towels/footwear

Additional Reading

  • Gonz ‘lez U, Seaton T, Bergus G, et al. Systemic antifungal therapy for tinea capitis in children. Cochrane Database Syst Rev. 2007;(4):CD004685.
  • Kelly BP. Superficial fungal infections. Pediatr Rev. 2012;33:e22 " e37.
  • Moriarty B, Hay R, Morris-Jones R. The diagnosis and management of tinea. BMJ. 2012;345:e4380.
  • Rashid RM, Miller AC, Silverberg, MA. Tinea in Emergency Medicine. May 9, 2011. http://emedicine.medscape.com/article/787217-overview.
  • Zhang AY, Camp WL, Elewski BE. Advances in topical and systemic antifungals. Dermatol Clin. 2007;25:165 " 183.

Codes

ICD9

  • 110.0 Dermatophytosis of scalp and beard
  • 110.1 Dermatophytosis of nail
  • 110.5 Dermatophytosis of the body
  • 110.3 Dermatophytosis of groin and perianal area
  • 110.2 Dermatophytosis of hand
  • 110.4 Dermatophytosis of foot

ICD10

  • B35.0 Tinea barbae and tinea capitis
  • B35.1 Tinea unguium
  • B35.4 Tinea corporis
  • B35.6 Tinea cruris
  • B35.2 Tinea manuum
  • B35.3 Tinea pedis

SNOMED

  • 5441008 Tinea capitis (disorder)
  • 84849002 Tinea corporis (disorder)
  • 402134005 Onychomycosis due to dermatophyte (disorder)
  • 399029005 Tinea cruris (disorder)
  • 48971001 Tinea manus (disorder)
  • 6020002 Tinea pedis (disorder)