Basics
Description
- Superficial fungal infections of the hair, skin, or nails:
- Usually confined to the stratum corneum layer
- Among the most common diseases worldwide
- Requires keratin for growth, so does not involve mucosa
- Named for location of infection
Etiology
- Dermatophytes:
- Microsporum
- Trichophyton
- Epidermophyton
- Malassezia 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 syndrome
- Immunosuppression
- Tinea pedis or capitis
Diagnosis
Signs and Symptoms
- Tinea capitis:
- Children are predominately affected
- Most contagious dermatophytosis
- Alopecia, dandruff-like scaling
- Kerion:
- 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 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
- More common in adults than children
- Most common tinea infection in US
- "Trichophytid " reaction:
- Vesicular eruption remote from infection
- Involving hands, mimics dyshidrotic eczema
- Tinea unguium:
- 1 type of onychomycosis
- Yellow or brown discoloration with thickening and debris under the nails
- Onycholysis: Loosening of the nail from bed
- May involve the plantar surface of the foot
- 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
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 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
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 food
- 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
- Selenium sulfide or ketoconazole shampoo reduces transmissibility
- Kerion 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 course
- Oral therapy may be necessary for cases resistant to topical treatment or for immunocompromised patients
- Keep the area dry (talc powders) and frequently change socks and underclothes
- Tinea unguium:
- Requires oral therapy and longer course than other tinea infections
- Terbinafine had a slightly higher cure rate than imidazoles (ketoconazole, miconazole, and clotrimazole) or griseofulvin in a meta-analysis
- Ciclopirox 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 ketoconazole
- Oral 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 common
- Patients 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)