Tinea infectionMANAGEMENT

INFECTIOUS DISEASE PRESENTATIONS · 12 SECTIONS

⚲

488 items

☷ Legend

01Approach to the Critical Patient/attcp42

Stabilization triggers

›Immediate escalation triggers

›Fever with rapidly progressive erythema

›Necrotizing soft tissue infection concern

›Broad-spectrum antibiotics pathway instead of isolated tinea pathway

›Periorbital or facial involvement with eye pain or vision change

›Orbital cellulitis concern

›CT orbit and IV antibiotics pathway

›Immunocompromised with widespread skin breakdown

›Disseminated infection risk

›Lower threshold for admission

›Kerion with significant scalp swelling

›Secondary bacterial infection concern

›Urgent dermatology or pediatrics involvement

Initial clinical framing

›Dermatophyte syndrome identification

›Anatomic site patterning

›Body tinea corporis

›Groin tinea cruris

›Feet tinea pedis

›Hands tinea manuum

›Scalp tinea capitis

›Beard area tinea barbae

›Nails onychomycosis tinea unguium

›High-risk presentations

›Scalp involvement

›Nail involvement

›Refractory disease after topical therapy

›Extensive surface area involvement

›Infection control priorities

›Household transmission risk

›Team sports exposure risk

›Shared towels and bedding exposure risk

Diagnostic confirmation strategy

›Bedside confirmation options

›KOH microscopy from active border scale

›Highest yield from leading edge

›False negative risk with recent antifungal use

›Fungal culture

›Atypical morphology

›Treatment failure or recurrence

›Species and susceptibility pathway

›Resistant dermatophytosis concern

›Dermatophyte species identification

›Antifungal susceptibility testing when available

02History/hx39

Symptom and exposure inventory

›History elements

›Rash onset and tempo

›Gradual centrifugal expansion

›Pruritus severity

›Prior treatments

›Topical steroid exposure

›Over-the-counter antifungal exposure

›Exposure risks

›Household contacts with similar rash

›Contact sports

›Shared showers or locker rooms

›Occlusive footwear

›Pets with alopecia or scaling

›Recent travel or new sexual contacts with extensive tinea pattern

›Site-specific features

›Foot maceration between toes

›Groin sparing of scrotum pattern

›Scalp scale with hair breakage

›Nail thickening and onycholysis

›Host risk factors

›Diabetes mellitus

›Immunosuppression

›HIV risk or known HIV

›Atopic dermatitis

›Hyperhidrosis

Red flags and complications

›Complication screening

›Pain out of proportion

›Necrotizing infection concern

›Fever or chills

›Secondary bacterial infection concern

›Pus or crusting

›Impetiginization concern

›Scalp bogginess

›Kerion concern

›Lymphadenopathy

›Inflammatory tinea capitis pattern

›Recurrent rash after partial response

›Reinfection from contacts or fomites

›Resistant dermatophyte concern

03Physical Exam/exam35

Skin and appendage survey

›Examination domains

›Lesion morphology

›Annular plaque with peripheral scale

›Central clearing pattern

›Vesicles at advancing edge

›Hyperpigmented inflammatory plaque pattern

›Distribution mapping

›Groin and inner thigh involvement

›Interdigital toe web involvement

›Moccasin distribution plantar scaling

›One hand two feet pattern

›Scalp patches with broken hairs

›Nail examination

›Distal lateral subungual debris

›Nail plate thickening

›Onycholysis

›Number of nails involved

›Signs of steroid modification

›Less scale with more erythema

›Pustular or extensive plaque pattern

Complication assessment

›Complication findings

›Surrounding cellulitis

›Warmth and tenderness beyond scale border

›Lymphangitic streaking

›Secondary bacterial infection

›Honey crust

›Purulent drainage

›Kerion features

›Boggy tender plaque

›Pustules

›Regional lymphadenopathy

›Alternate diagnosis clues

›Silvery scale with extensor distribution

›Satellite pustules in intertrigo

›Diffuse xerosis without annular border

04Differential Diagnosis/ddx36

Dermatologic mimics

›Annular and intertriginous mimics

›Nummular eczema

›Lack of active scaly border

›Psoriasis

›Extensor plaques

›Nail pitting

›Pityriasis rosea

›Herald patch

›Christmas tree distribution

›Granuloma annulare

›Non-scaling annular papules

›Erythrasma

›Brown-red patches in folds

›Coral-red fluorescence on Wood lamp

›Candida intertrigo

›Beefy erythema with satellite pustules

Site-specific differentials and coding anchors

›Scalp and hair differentials

›Seborrheic dermatitis

›Diffuse greasy scale

›Alopecia areata

›Smooth patches without scale

›Bacterial folliculitis

›Follicular pustules

›Nail differentials

›Traumatic dystrophy

›Psoriatic nail disease

›Lichen planus nail disease

›ICD-10 dermatophyte codes

›B35.0 tinea barbae and tinea capitis

›B35.1 tinea unguium

›B35.2 tinea manuum

›B35.3 tinea pedis

›B35.4 tinea corporis

›B35.6 tinea cruris

›B35.8 other dermatophytoses

›B35.9 dermatophytosis unspecified

05Laboratory Tests/lt27

Bedside mycology

›Direct testing

›KOH preparation

›Indication atypical appearance

›Indication treatment failure

›Specimen leading edge scale

›Hyphae identification supports dermatophyte infection

›Fungal culture

›Indication tinea capitis suspected

›Indication onychomycosis confirmation before systemic therapy

›Indication suspected resistance or outbreak

Safety monitoring for systemic therapy

›Baseline risk stratification labs

›Hepatic enzymes

›Indication planned oral terbinafine or itraconazole

›Higher priority with known liver disease

›Complete blood count

›Indication prolonged systemic therapy

›Indication immunocompromised host

›Pregnancy test when relevant

›Indication systemic azole consideration

›Indication uncertain pregnancy status

Co-infection and host factor labs

›Associated testing

›Glucose or HbA1c pathway when indicated

›Recurrent tinea pedis or onychomycosis

›Poor wound healing

›HIV testing pathway when indicated

›Extensive or refractory dermatophytosis

›Opportunistic infection concern

06Diagnostic Tests/dt47

Scoring Systems

›Severity stratification tools

›Onychomycosis Severity Index

›Inputs

›Area of nail involvement

›Proximity to nail matrix

›Dermatophytoma presence

›Subungual hyperkeratosis thickness greater than 2 mm

›Interpretation bands

›Mild score 1 to 5

›Moderate score 6 to 15

›Severe score 16 to 35

›Clinical pattern classification for tinea pedis

›Interdigital type

›Maceration and fissuring

›Hyperkeratotic moccasin type

›Diffuse plantar scaling

›Vesiculobullous type

›Vesicles on arch or plantar surface

MRI

›Advanced imaging indications

›Suspected osteomyelitis in diabetic foot context

›Persistent pain and swelling

›Nonhealing ulcer with concomitant tinea pedis

›Deep space infection concern

›Severe pain

›Systemic toxicity

›MRI limitations for superficial tinea

›Not a routine test for dermatophyte diagnosis

›Use only for complications

›CT indications

›Orbital or facial complication concern

›Periorbital swelling with pain

›Vision symptoms

›Necrotizing infection concern

›Gas in soft tissues

›Fascial thickening

›CT limitations for superficial tinea

›Not a diagnostic test for dermatophytosis

›Use only for alternate diagnosis or complication

Ultrasound

›Ultrasound applications

›Abscess evaluation in superinfected lesions

›Fluctuant or tender mass

›Drainable collection identification

›Lymph node assessment in inflammatory scalp disease

›Reactive adenopathy support

›Ultrasound limitations for superficial tinea

›Does not confirm dermatophyte etiology

›Adjunct for complications only

07Disposition/dispo27

Level of care decisions

›Outpatient management default

›Uncomplicated localized tinea corporis cruris pedis

›Topical therapy plan

›Hygiene and transmission counseling

›Stable tinea capitis without systemic illness

›Systemic therapy plan

›Close follow-up plan

›Admission or observation considerations

›Extensive skin involvement with systemic symptoms

›Secondary bacterial infection pathway

›Immunocompromised with widespread disease

›Rapid progression risk

›Specialist involvement threshold lower

›Severe cellulitis overlying tinea pedis

›IV antibiotics pathway

›Limb threat risk

Follow-up and referral

›Specialty follow-up triggers

›Refractory disease after appropriate course

›Fungal culture and speciation

›Resistance concern workup

›Kerion

›Dermatology or pediatrics follow-up within 24 to 72 hours

›Onychomycosis with systemic therapy plan

›Primary care or dermatology follow-up for monitoring

›Diagnostic uncertainty

›Dermatology evaluation

›Biopsy consideration if nonfungal etiologies suspected

08Treatment/t123

Nonpharmacologic and infection control

›Supportive measures

›Skin care

›Keep area dry

›Loose breathable clothing

›Fomite control

›Daily sock change

›Hot wash towels and bedding

›Do not share razors hats hairbrushes

›Footwear interventions

›Dry shoes fully between uses

›Antifungal powder in shoes

›Contact management

›Treat symptomatic household contacts

›Veterinary evaluation for symptomatic pets

Topical therapy

›Topical antifungal strategy

›Allylamines

›Terbinafine 1 percent cream

›Frequency once daily

›Duration 1 to 2 weeks

›Naftifine 1 percent cream

›Frequency once daily

›Duration 2 to 4 weeks

›Benzylamines

›Butenafine 1 percent cream

›Frequency once daily

›Duration 2 weeks

›Azoles

›Clotrimazole 1 percent cream

›Frequency twice daily

›Duration 2 to 4 weeks

›Miconazole 2 percent cream

›Frequency twice daily

›Duration 2 to 4 weeks

›Ketoconazole 2 percent cream

›Frequency once daily

›Duration 2 to 4 weeks

›Hydroxypyridones

›Ciclopirox 0.77 percent cream

›Frequency twice daily

›Duration 2 to 4 weeks

›Application principles

›Continue 1 week after clinical clearing

›Relapse reduction rationale

›Cover lesion plus 2 cm margin

›Edge hyphae burden rationale

›Avoid topical corticosteroid monotherapy

›Tinea incognito risk

Systemic therapy

›Indications for oral agents

›Tinea capitis

›Topicals insufficient due to follicular involvement

›Tinea barbae

›Follicular depth involvement

›Extensive tinea corporis or cruris

›Multiple sites or large surface area

›Refractory disease after adherent topical course

›Culture and speciation pathway

›Onychomycosis with functional or pain burden

›Confirmation testing preferred before systemic therapy

›Terbinafine oral

›Adult dermatophyte skin infection dosing

›Terbinafine 250 mg daily

›Duration tinea corporis 2 to 4 weeks

›Duration tinea cruris 2 to 4 weeks

›Duration tinea pedis 2 to 6 weeks

›Adult onychomycosis dosing

›Terbinafine 250 mg daily

›Duration fingernails 6 weeks

›Duration toenails 12 weeks

›Pediatric tinea capitis dosing

›Weight-based regimen per pediatric references

›Approximate range 5 to 8 mg per kg per day

›Typical duration 4 to 6 weeks

›Safety considerations

›Hepatotoxicity risk

›Baseline hepatic enzymes when prolonged course planned

›Drug interactions via CYP2D6 inhibition

›Tricyclic antidepressants interaction potential

›Beta blocker interaction potential

›Griseofulvin oral

›Primary role tinea capitis

›Microsize dosing

›20 to 25 mg per kg per day

›Duration 6 to 8 weeks

›Ultramicrosize dosing

›10 to 15 mg per kg per day

›Duration 6 to 8 weeks

›Administration considerations

›Take with fatty meal

›Absorption improvement

›Safety considerations

›Pregnancy contraindication

›Teratogenicity concern

›Azole systemic alternatives

›Itraconazole oral

›Pulse or continuous regimens per specialist pathway

›Drug interaction burden

›Heart failure contraindication concern

›Resistant dermatophytosis option in consultation pathway

›Suspected terbinafine resistance

›Fluconazole oral

›Alternative tinea capitis option

›Weekly or daily regimens per specialist pathway

›Adjunct scalp measures in tinea capitis

›Selenium sulfide shampoo 2.5 percent

›Frequency 2 to 3 times weekly

›Duration first 2 weeks of systemic therapy

›Ketoconazole shampoo 2 percent

›Frequency 2 to 3 times weekly

›Transmission reduction rationale

Nail-specific therapy

›Topical nail options

›Efinaconazole 10 percent solution

›Daily application

›Prolonged course months scale

›Tavaborole 5 percent solution

›Daily application

›Prolonged course months scale

›Ciclopirox 8 percent lacquer

›Daily application with weekly debridement

›Lower cure rates relative to oral therapy

›Debridement strategy

›Mechanical trimming

›Reduced fungal burden

›Improved topical penetration

09Special Populations/sp31

Pregnancy

›Pregnancy considerations

›Topical therapy preference

›Minimal systemic absorption

›First-line for localized disease

›Systemic azole caution

›Teratogenicity concerns with high-dose or prolonged exposure

›Specialist involvement for systemic need

›Griseofulvin avoidance

›Pregnancy contraindication

›Breastfeeding considerations

›Minimize systemic exposure when possible

›Shared decision-making for oral agents

Geriatric

›Older adult considerations

›Polypharmacy interaction risk

›Terbinafine CYP2D6 interaction potential

›Itraconazole interaction burden

›Hepatic reserve considerations

›Baseline hepatic enzymes when systemic therapy planned

›Peripheral vascular disease and diabetes overlap

›Foot skin breakdown risk

›Secondary bacterial infection risk

Pediatrics

›Pediatric considerations

›Tinea capitis prevalence emphasis

›Systemic therapy required

›School and household transmission counseling

›Weight-based dosing necessity

›Terbinafine weight-based regimen

›Griseofulvin weight-based regimen

›Kerion management pathway

›Urgent follow-up

›Secondary bacterial infection assessment

10Background/b32

Epidemiology

›Population patterns

›Common superficial fungal infection group

›High household transmission potential

›Tinea pedis and onychomycosis association

›Shared reservoir concept

›Tinea capitis pediatric predominance

›School and daycare clustering

›Emerging resistant dermatophytosis

›Increasing reports of severe atypical cases

Pathophysiology

›Dermatophyte biology

›Keratinophilic fungi

›Stratum corneum invasion

›Hair shaft invasion in capitis and barbae

›Nail plate invasion in onychomycosis

›Inflammatory host response variation

›Kerion as intense inflammatory reaction

›Steroid modification

›Altered morphology with reduced scale

Therapeutic Considerations

›Treatment principles

›Site penetration dictates therapy

›Hair and nails require systemic or prolonged targeted therapy

›Duration depends on keratin turnover

›Nails require weeks to months courses

›Transmission prevention reduces recurrence

›Fomite decontamination

›Treat foot reservoir to protect nails

›Resistant dermatophyte considerations

›Culture and susceptibility when refractory

›Itraconazole use in resistant cases in consultation pathway

›Evidence framing for common practices

›Topicals for 2 to 4 weeks typical for skin tinea patterns

›Terbinafine oral 250 mg daily typical for adult skin tinea 2 to 6 weeks

11Patient Discharge Instructions/pdi28

Copy discharge instructions

›Discharge packet

›Diagnosis explanation

›Superficial fungal infection of skin hair or nails

›Contagious through direct contact and shared items

›Medication use

›Apply topical antifungal exactly as directed

›Continue for full recommended duration even if better

›Apply beyond visible rash edge

›Hygiene and prevention

›Keep area clean and dry

›Change socks daily

›Do not share towels clothing hats hairbrushes razors

›Wash towels and bedding in hot water

›Wear sandals in shared showers

›Treat athlete foot promptly to prevent nail infection

›Household guidance

›Check household members for similar rash

›Pets with hair loss need veterinary assessment

›Return to care urgently

›Fever

›Rapidly spreading redness or severe pain

›Pus drainage

›Facial or eye involvement

›Scalp swelling or painful boggy area

›No improvement after 2 weeks of correct use

›Follow-up plan

›Primary care or dermatology if persistent or recurrent

›Blood test monitoring if on oral antifungals when advised

12References/r21

Guidelines and evidence sources

›Reference set

›CDC ringworm treatment guidance

›Topical antifungals typically 2 to 4 weeks for skin tinea

›CDC clinician brief on emerging and resistant dermatophytosis

›Resistant strains reported

›Species identification and susceptibility testing for suspected resistance

›AAFP diagnosis and management of tinea infections

›KOH or culture when appearance atypical

›Systemic therapy for tinea capitis

›Carney Onychomycosis Severity Index consensus system

›Severity score bands 1 to 5 mild

›Severity score bands 6 to 15 moderate

›Severity score bands 16 to 35 severe

›StatPearls tinea corporis review

›Terbinafine 250 mg daily 2 to 4 weeks for tinea corporis

›StatPearls tinea capitis review

›Systemic therapy requirement

›Typical treatment duration 4 to 8 weeks

›Mayo Clinic terbinafine dosing monograph

›Adult tinea skin dosing ranges

›Adult onychomycosis duration ranges

Evidence & Review

Reviewed by SymptomDx Medical Team · Last reviewed June 16, 2026

SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.