Granuloma annulare Flashcards
Age group most affected by Granuloma annulare:
- children and young adults (two-thirds arise before 30 y/o)
cause of Granuloma annulare?
unknown
possible associated triggers for Granuloma annulare:
- trauma
- insect bites
- mycobacterial/viral infection
- UV radiation
What is the pagthogenesis of Granuloma annulare?
- Trigger—> Th1 reaction–> monocyte accumulation in dermis —> release of lysosomal enzymes—> degradation of elastic fibers
Is localized GA associated with underlying comorbidities?
No, majority of localized GA patients are health (generalized GA is a/w type I diabetes, hyperlipidemia, HIV, thyroid disease, malignancy)
What are the underlying diseases/associations with generalized GA?
generalized GA is a/w type I diabetes,
hyperlipidemia,
HIV,
thyroid disease,
malignancy
What is the classic presentation of granloma annulare?
- annular/arciform plaques comprised of multiple small, non-scaly flesh-colored to pink or violaceous papules
What are the most commonly affected areas of body with granloma annulare?
isolated to hands/arms in 60% of cases
Patch GA presents as:
- basically GA that is flat/barely palpable
- symmetrical erythematous pathces commonly on bilateral dorsal feet (often lacks annular configuration)
deep GA presents as:
- asymptomatic rheumatoid-like nodules on Dorsal foot most commonly, often a/w trauma
Deep GA is often a/w____
Trauma
What is the prognosis of granloma annulare?
Benign, self-resolving, asymptomatic (but can mildy itchy)
What is the prognosis of Generalized granloma annulare?
usually self-resolves in 3-4 years
Histopath of GA?
- granulomatous dermal inflammation
- foci of collagen/elastic fiber degeneration
- increased mucin
What are the three histological patterns of GA?
- Interstitial (most common): singly-arrayed histiocytes between collagen fibers (key to diagnosis is increased dermal mucin between collagen)
- Palisaded granulomas (25%)
- Sarcoidal pattern (5%)
