Dermatology Book

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Tinea CorporisAka: Tinea Circinata, Ringworm

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  1. Etiology
    1. Trichophyton rubrum
    2. Epidermophyton floccosum
    3. Trichophyton tonsurans
    4. Trichophyton mentagrophytes
    5. Microsporum canis
  2. Pathophysiology
    1. Infection
      1. Exposure to contaminated soil
      2. Exposure to infected animals or people
    2. Growth and transmission facilitating factors
      1. Warm and moist environments (showers and pools)
      2. Shared towels or clothing
  3. Signs
    1. Location: Glabrous skin (excludes palms, soles, groin)
    2. Characteristics
      1. Round, erythematous, Scaling, pruritic Plaques
      2. Annular Lesion (hence the name ringworm)
        1. Raised, advancing border
        2. Plaque with central clearing
          1. No central clearing after Corticosteroid use
      3. Postinflammatory pigmentation changes
  4. Precautions
    1. Widespread ringworm suggests underlying disease
  5. Lab
    1. Potassium Hydroxide (KOH 20%)
      1. Scrape from active border
    2. Chlorazol black
      1. Highlights fungal hyphae
    3. Fungal Culture
      1. Suspected dermatophyte infection despite negative KOH
      2. Dermatophyte testing medium (DTM)
    4. Biopsy
      1. PAS stain will show hyphae in Stratum Corneum
  6. Differential Diagnosis
    1. See Annular Lesion
    2. Pityriasis Rosea (Herald patch)
    3. Nummular eczema
    4. Drug allergy or drug eruption
    5. Psoriasis
    6. Erythema Multiforme
    7. Contact Dermatitis
    8. Discoid Lupus
    9. Bowen's Disease
    10. Parapsoriasis
    11. Mycosis Fungoides (Cutaneous T Cell Lymphoma)
    12. Granuloma Annulare
    13. Secondary Syphilis
  7. Management
    1. Prevent re-infection (see pathophysiology above)
    2. Topical Antifungal applied twice daily for 2-3 weeks
      1. Technique
        1. Apply to infected and normal skin 2 cm beyond affected area
        2. Continue for 7 days after symptom resolution
      2. First line: Imidazoles (e.g. Clotrimazole)
      3. Refractory cases: Naftin, Lamisil, Loprox, Mentax
    3. Systemic Antifungal
      1. Indications
        1. Immunocompromised patient
        2. Disabling or widespread lesions
        3. Chronic infection
        4. Hyperkeratotic area involvement (palms or soles)
      2. Duration
        1. Start with 2-4 week course
        2. Consider extending prescription for additional 2-4 week course
      3. Preparations
        1. Terbinafine 250 mg orally daily
        2. Fluconazole 150 mg orally once per week
        3. Itraconazole (Sporanox)
        4. Griseofulvin 0.5-1.0 grams per day
        5. Ketoconazole 200 mg orally daily
          1. Not recommended due to potential hepatic injury
  8. Complications
    1. Deep follicular Tinea Infection (Majocchi's Granuloma)
      1. Complication of Topical Corticosteroid use
      2. More commonly affects women, and most often on legs
  9. References
    1. Gilbert (1999) Sanford Guide to Antimicrobials
    2. Andrews (2008) Am Fam Physician 77(10):1415
    3. Schwartz (2004) Lancet 364(9440):1173
    4. Drake (1996) J Am Acad Dermatol 34(2 pt 1):282
    5. Hsu (2001) Am Fam Physician 64(2):289

Tinea (C0040247)

Definition (MSH)A general term describing various dermatophytoses. Specific types include TINEA CAPITIS (ringworm of the scalp), TINEA FAVOSA (of scalp and skin), TINEA PEDIS (athlete's foot), and tinea unguium (see ONYCHOMYCOSIS, ringworm of the nails). (Dorland, 27th ed)
Definition (CSP)general term describing various dermatophytoses; specific types include tinea capitis (ringworm of the scalp), tinea favosa (of scalp and skin), tinea pedis (athlete's foot), and tinea unguium (ringworm of the nails).
ConceptsDisease or Syndrome (T047)
ICD9110.9
MSHD014005
EnglishDermatophytosis-tinea/ringworm, Microsporic tinea, ringworm, Tinea, Tinea Infections, Tineas
Spanishserpigo, tina, tina microsporica
Parent ConceptsDermatomycoses (C0011630)
SourcesAOD, COSTAR, CSP, MEDLINEPLUS, MSH, MTH, MTHICD9, NDFRT, SCTSPA, SNOMEDCT
Derived from the NIH UMLS (Unified Medical Language System)


Tinea corporis (disorder) (C0040252)

ConceptsDisease or Syndrome (T047)
ICD9110.5
EnglishBody tinea, Herpes circinatus, Ringworm of body, Tinea circinata, Tinea circinatus, Tinea corporis
Spanishherpes circinado, tina circinada, tina del cuerpo, tricofitosis del cuerpo
Parent ConceptsDermatophytosis of the body (C0546826), Duplicate concept (C1274013)
SourcesCOSTAR, MTH, MTHICD9, SCTSPA, SNOMEDCT
Derived from the NIH UMLS (Unified Medical Language System)



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