Dermatophytosis

Background

  • Also known as ringworm
  • Common fungal infection of the skin, hair and nails
  • Mode of transmission via direct contact to the organisms (eg. using unwashed wrestling mats)
  • These dermatophytes are filamentous fungi that live off the keratin

Clinical Features

Dermatophytosis.png

Subtypes of infections include:

  • Tinea corporis (ringworm)
    • Body except for feet, groin, face, scalp hair or beard hair
    • Clinical manifestation:
      • Pruritic, circular scaly patch or plaque → central clearing → annular plaque
  • Tinea pedis (athlete's foot)
    • Foot
    • Clinical manifestation:
      • Between digit spaces
      • Pruritic
      • Erosions
      • Scales
      • Bullous
  • Tinea cruris (jock itch)
    • Groin
    • Clinical manifestation:
      • Erythematous patch on proximal inner thigh → central clearing with sharp borders and vesicles
      • Scrotum typically spared
  • Tinea capitis
    • Scalp hair
    • Clinical manifestation:
      • Scaly patches with alopecia
  • Tinea unguium (Dermatophyte onchomycosis)
    • Nail
    • Clinical manifestation:

Differential Diagnosis

Tinea pedis

  • Interdigital candida infection
  • Erythrasma
  • Atopic dermatitis
  • Chronic contact dermatitis
  • Acute palmoplantar eczema
  • Palmoplantar psoriasis
  • Pitted keratolysis
  • Juvenile plantar dermatosis
  • Keratolysis exfoliativa
  • Keratodermas
  • Acute palmoplantar eczema
  • Acute contact dermatitis
  • Palmoplantar pustulosis
  • Scabies

Tinea cruris

  • Inverse psoriasis
  • Erythrasma
  • Seborrheic dermatitis
  • Candidal intertrigo

Tinea corporis

  • Subacute cutaneous lupus erythematosus (SCLE)
  • Granuloma annulare
  • Erythema annulare centrifugum

Evaluation

KOH prep for diagnosis

Management

Tinea coporis

  • Topical antifungals (azoles, allylamines, butenafine, ciclopirox, and tolnaftate)
  • Oral antifungals for those who fail topical treatment

Tinea pedis

  • Topical antifungals
  • Oral antifungals (terbinafine, itraconazole, or fluconazole)

Tinea cruris

  • Topical antifungals

Tinea capitis

Tinea unguium

  • Mild to moderate
    • 1st line
      • Oral terbinafine
      • Topical efinaconazole, amorolfine, tavaborole, and ciclopirox
  • Moderate to severe
    • Terbinafine, itraconazole

Disposition

See Also

External Links

References