Derm

Granuloma Annulare

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Granuloma Annulare

  • Definition
  1. Benign, self-limited annular rash in age <30 years
  • Epidemiology
  1. Occurs most commonly in young women
  2. Most patients are under age 30 years
  • Associated Conditions
  1. Most cases occur without underlying condition
  2. Diabetes Mellitus (up to 12% of cases)
  3. Post-Skin Trauma (e.g. Insect Bites)
  4. Following Tuberculin Skin Tests
  5. Malignancy: Lymphoma (usually), Prostate Cancer
  6. Viral infections
    1. Epstein Barr Virus
    2. Herpes Zoster
    3. HIV Infection
  • Symptoms
  1. Asymptomatic or mild Pruritus
  • Signs
  1. Characteristics
    1. Initial
      1. Flesh-colored Papule
      2. Papule involutes centrally
      3. Forms Annular Lesion (ring shape)
    2. Later
      1. Ring of Papules enlarges up to 5 cm diameter
  2. Distribution
    1. Dorsolateral feet and ankles (most common)
    2. Dorsolateral hands and wrists
    3. Less commonly may occur anywhere
  3. Other distinguishing features
    1. Palms, Scalp and Plantar surfaces spared
    2. No scale
    3. No associated Vesicles or Papules
  • Types
  1. Localized Granuloma Annulare (75% of cases)
    1. Typical distribution as above
    2. Spontaneous resolution by 2 years in 50% of cases
  2. Disseminated Granuloma Annulare
    1. Ten or more lesions with widespread involvement
    2. Increased association with Diabetes Mellitus
    3. Lesions may persist for >4 years
  3. Generalized perforating Granuloma Annulare (rare)
    1. Small umbilicated 1-4 mm Papules
    2. Seen in children and young adults
    3. Distribution
      1. Localized form: arms, Pelvis
      2. Generalized form: Trunk, Abdomen, arms, legs
  4. Subcutaneous Granuloma Annulare
    1. Large, deep Skin-Colored Nodules
    2. Young children (Age 2-5 years)
    3. Distribution
      1. Hands and fingers
      2. Scalp
      3. Buttocks
      4. Elbows and knees
      5. Perioral
    4. May occur in clusters
    5. No associated underlying conditions
  5. Actinic Granuloma Annulare
    1. Sun-exposed skin involvement
  • Differential Diagnosis
  1. See Annular Lesions
  2. Distinguishing features of Granuloma Annulare
    1. Smooth skin surface
    2. No overlying scale
    3. No associated Vesicles or Pustules
  3. Similar appearing lesions
    1. Tinea manus or Tinea Corporis
      1. Scale, Papules or Vesicles present
    2. Erythema Migrans (Lyme Disease)
    3. Tertiary Syphilis
    4. Nummular Eczema
    5. Psoriasis
    6. Erythema annulare centrifigum
    7. Discoid Lupus
    8. Sarcoidosis
  • Labs
  1. Fasting Glucose
    1. Glucose Intolerance common
  2. Biopsy
    1. May appear similar to Necrobiosis Lipoidica
    2. Characteristic findings
      1. Epithelioid histiocytes surround anuclear Dermis
      2. Mucin deposition
      3. May be reported as focal collagen degeneration
        1. With reactive inflammation and fibrosis
  • Management
  1. Most lesions do not require treatment
  2. All treatments risk scarring
  3. Corticosteroids
    1. Intralesional Corticosteroid
      1. Kenalog 2.5 to 5 mg/ml injected into raised border
    2. Topical Corticosteroids under Occlusion
  4. Cryotherapy
  5. Treatments for refractory cases (by Dermatologists)
    1. All based on case reports of <10 patients per study
    2. Toxicity limits use in primary care
    3. Include: Dapsone, Accutane, Fumaric acid esters
  • Course
  1. Resolution without treatment within months to 2 years
  2. Recurrence occurs in 40% of children
  3. Types associated with slower and incomplete resolution
    1. Disseminated Granuloma Annulare