Fungus

Tinea Cruris

search

Tinea Cruris, Jock Itch

  • See Also
  1. Intertrigo
  2. Erythrasma
  • Pathophysiology
  1. Often associated with Tinea Pedis
  2. Groin inoculated with patient's hands
  • Etiology (same as Tinea Pedis)
  1. Trichophyton rubrum
  2. Trichophyton mentagrophytes
  3. Epidermophyton floccosum
  • Epidemiology
  1. More common in teen and young adult males
  2. Also common in teen females who are Overweight or wear occlusive clothing
  • Signs
  1. Distribution
    1. Bilateral thighs
    2. Inguinal folds
    3. Buttocks
  2. Spared areas: Scrotum and penis
    1. Suspect Cutaneous Candidiasis if involved
  3. Characteristics
    1. Asymmetric erythematous annular Plaques
      1. Scaling
      2. Central clearing
    2. Occasional Papules or Vesicles
  • Differential Diagnosis
  1. Candidiasis (Intertrigo)
  2. Seborrheic Dermatitis
  3. Erythrasma (fluoresces coral red under wood's lamp)
  4. Psoriasis (Inverse)
  5. Lichen Simplex Chronicus
  6. Pemphigus
  7. Contact Dermatitis
  8. Extramammary Paget's Disease
  • Management
  1. Treat concurrent Tinea Pedis if present
  2. Topical Antifungal cream bid for 2-4 weeks
    1. Technique
      1. Apply to 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
      1. Ciclopirox (Loprox)
      2. Terbinafine (Lamisil)
      3. Butenafine (Mentax)
      4. Naftifine (Naftin)
  3. Loose fitting clothes, boxer shorts
  4. Powders to reduce moisture
  5. Antibacterial soap
  • References
  1. Andrews (2008) Am Fam Physician 77(10): 1415-20 [PubMed]
  2. Caplan (2025) Am Fam Physician 112(4): 382-92 [PubMed]
  3. Schwartz (2004) Lancet 364(9440):1173-82 [PubMed]