NON-INFECTIOUS GRANULOMATOUS DERMATITIS & HISTIOCYTIC DISEASES Flashcards
Conditions with sarcoidal granuloma
Lichen nitidus, Sarcoidosis
Conditions with Tuberculoid granuloma
TB, Leprosy
Conditions with palisaded granuloma
Granuloma annulare, Necrobiosis lipoidica, Rheumatoid nodule, Gout
Conditions with suppurative granuloma
Ruptured follicular cyst, Infections
Langhans type giant cells: Collection of macrophages in a Horseshoe-shaped pattern
Langerhans cells: Dendritic cells in the skin and bone marrow with immune response function
Foam cells / Xanthomatous cells: Lipid-laden macrophages
Necrobiosis: Degeneration of collagen; blurring and loss of definition of collagen bundles possibly due to mucin, fibrin, lipids etc
Asteroid body: Stellate inclusion bodies composed of crystalline inclusions (lipoproteins, calcium, phosporus, etc) seen in granulomatous diseases like sarcoidosis, sporotrichosis, etc
Conchoidal body / Schaumann body: Large concentric calcifications containing protein, calcium oxalate, and iron seen in granulomatous diseases (sarcoidosis, Crohns, foreign body reaction etc.)
Identify what type of giant cells
What type of granuloma
Sarcoidosis
- Naked granuloma
- Non-caseating, well-demarcated granulomas with sparse lymphocytes
- normal epidermis
PALISADED GRANULOMA
What is located at the center of the palisaded granuloma in granuloma annulare?
Mucin
What is located at the center of the palisaded granuloma in Rheumatoid nodule ?
Degenerated collagen
What is located at the center of the palisaded granuloma in necrobiosis lipoidica?
Degenerated collagen + lipid
What is located at the center of the palisaded granuloma in necrobiotic xanthogranuloma?
Cholesterol clefts
Granuloma Annulare
*Palisading granuloma with central necrobiosis
*no fibrosis
*abundant mucin in central area
*No plasma cells seen (unlike necrobiosis lipoidica)
Necrobiosis lipoidica
*“tiers/layers of cake”
*Broad horizontal tiers of degenerated collagen sandwiched between palisading granulomatous infiltrate
*plasma cells
*may have thrombi
*lipids in necrobiotic areas
*no mucin
Rheumatoid nodule
- Deep in dermis/subcutis
- Irregular areas of necrobiosis with palisade of elongated histiocytes
- Fibrin, homogeneous, eosinophilic necrobiotic area
- Eosinophils & lymphos
- no mucin
Ruptured Follicular cyst
*Suppurative granuloma around cyst or hair follicle
*Foreign body giant cells
*Keratin spicules engulfed by MNGC
*+/-Scar tissue formation
Xanthogranuloma
*Nodular, poorly demarcated dense infiltrate of small foamy histiocytes in dermis
*Touton giant cells
*Eosinophils
Xanthoma
*Aggregates of lipidladen cells (xanthomatous cells)
*Epidermis (may vary based on type)
*Few scattered inflammatory cells
Necrobiotic xanthogranuloma
*Palisading granuloma with focal hyaline necrobiosis
*numerous giant cells, foam cells and bizarre histiocytes
*(+) cholesterol clefts
* May be similar to NLD, but significantly different clinically
