Ch. 10 - Granulomatous and histiocytic diseases

Question 1

Recite some categories of granulomas.

Answer 1

Sarcoidal (little surrounding infiltrate)

Tuberculoid (caseous necrosis)

Palisading (necrobiosis, foreign material)

Suppurative (neutrophils)

Question 2

Granuloma annulare

Answer 2

Palisaded or interstitial granulomas in the upper dermis, with mucin. No cholesterol clefts, rare plasma cells.

Question 3

Actinic granuloma

Answer 3

Palisading granuloma with no mucin. Solar elastosis engulfed by giant cells and histiocytes. Central loss of elastic tissue.

Question 4

Necrobiosis lipoidica

(cause?)

Answer 4

Horizontal palisading granuloma with no mucin. Cholesterol clefts and plasma cells.

(diabetes-associated)

Question 5

Rheumatoid nodule

Answer 5

Large palisading granuloma surrounding eosinophilic fibrin. In deep dermis and subcutis. No mucin.

Question 6

Lupus miliaris disseminatus faciei (acne agminata)

Answer 6

Pea-like palisaded granuloma with central caseous necrosis. Resembles miliary TB, but actually rosaceous.

Question 7

Sarcoidosis

Answer 7

Epithelioid histiocytes forming discrete “naked” granuloma with minimal lymphocyte infiltrate and no necrosis. Can have schaumann bodies and asteroid bodies.

Question 8

What diseases should be considered in the differential for “naked” granulomas?

Answer 8

Sarcoidosis

Cutaneous crohn’s disease

Cheilitis granulomatosa

Tuberculoid leprosy

Silica/zirconium/beryllium granuloma

Granulomatous rosacea

Question 9

Necrotic xanthogranuloma

Answer 9

Granuloma with touton giant cells and x-shaped necrosis. Cholesterol clefts, neutrophilis debris, and lymphoplasmacytic follicles.

Question 10

Xanthogranuloma

Answer 10

Sea of histiocytes in dermis with later wreath giant cells and touton giant cells. No necrosis.

Question 11

Reticulohistiocytic granuloma (solitary reticulohistiocytoma)

Answer 11

Sea of histiocytes in dermis with punched out lacunae and two-toned cytoplasm. Dense glassy eosinophilic cytoplasm.

Question 12

Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy)

(IHC?)

Answer 12

Fibrotic nodules with sheets of lymphocytes and histiocytes. Emperipolesis (chronic inflammatory cells within histiocytes).

S100+, CD1a-, CD68+

Question 13

Langerhans cell histiocytosis (histiocytosis X)

(IHC?)

Answer 13

Polymorphous infiltrate with edema, hemorrhage, and reniform nuclei. Folliculotropism.

S100+, CD1a+, Langerin+

Question 14

Recall 3 forms of langerhans cell histiocytosis.

Answer 14

Letterer-Siwe: Disseminated and involves multiple organs

Hand-Schuller-Christian: DI, exophthalmos, lytic bone lesions

Eosinophilic granuloma: Localized to one site.

Question 15

What are xanthomas?

Answer 15

Accumulations of lipid in histiocytes. Can be due to disorders of lipoprotein metabolism or plasma cell dyscrasia.

Question 16

Xanthelasma

Answer 16

Band of foam cells in superficial or mid dermis. Eyelid location. Most common and unremarkable.

Question 17

Tuberous xanthoma

(cause?)

Answer 17

Fibrotic nodule with variable foam cells. Cholesterol clefts.

Indicates dyslipoproteinemias.

Question 18

Eruptive xanthoma

Answer 18

Foam cells and extracellular lipid, with sattered inflammatory infiltrate.

(very rapid lipid deposition resulting from increase in serum chylomicrons)

Question 19

Verruciform xanthoma

(cause?)

Answer 19

Papillomatosis with foam cells in the dermal papillae.

(may be due to degeneration of cells in the overlying epidermis)

Question 20

Answer 20

Interstitial granuloma annulare

Question 21

Answer 21

Palisading granuloma annulare

Question 22

Answer 22

Actinic granuloma

Question 23

Answer 23

Necrobiosis lipoidica

Question 24

Answer 24

Rheumatoid nodule

Question 25

Answer 25

Lupus miliaris disseminatus faciei (acne agnimata)

Question 26

Answer 26

Sarcoidosis

Question 27

Answer 27

Necrobiotic xanthogranuloma

Question 28

Answer 28

Xanthogranuloma

Question 29

Answer 29

Reticulohistiocytic xanthogranuloma

Question 30

Answer 30

Rosai-Dorfman disease

Question 31

Answer 31

Langerhans cell histiocytosis (histiocytosis X)

Question 32

Answer 32

Xanthelasma

Question 33

Answer 33

Tuberous xanthoma

Question 34

Answer 34

Eruptive xanthoma

Question 35

Answer 35

Eruptive xanthoma

Question 36

Answer 36

Verruciform xanthoma