Derm Path

Front 1

Necrobiotic (collagenolytic) granulomas are found in which conditions?

Back 1

-granuloma annulare and its variants
-necrobiosis lipoidica
-necrobiotic xanthogranuloma
-rheumatoid nodules
-rheumatic fever nodules
-reactions to foreign materials and vaccines
-miscellaneous diseases.

Front 2

Blue granulomas

Back 2

Granuloma annulare
Wegener’s granulomatosis
Rheumatoid nodules
The blue appearance is from increased amounts of connective tissue mucins (basophilic stringy material between collagen bundles), neutrophils and nuclear dust

Front 3

Red granulomas

Back 3

Necrobiosis lipoidica
Necrobiotic xanthogranuloma
Rheumatoid vasculitis
Pseudorheumatoid nodules of adults
Churg–Strauss syndrome
Eosinophilic cellulitis (Wells’ syndrome)
The red appearance is from fibrin, eosinophils, and flame figures

Front 4

Granuloma annulare: Clinical

Back 4

-Self-limited dermatosis of unknown etiology characterized by necrobiotic dermal papules that often assume an annular configuration
Either the skin or the subcutis, or both, may be involved.
Clinical variants of granuloma annulare include localized, generalized, perforating, and subcutaneous or deep forms

Front 5

Variants of Granuloma annulare

Back 5

In the localized form, one or more erythematous or skin-colored papules are found
Grouped papules tend to form annular or arciform plaques
The hands, feet, arms, and legs are the sites of predilection in some 80% of cases
In the generalized form, multiple macules, papules or nodules are distributed over the trunk and limbs
Accounts for approximately 15% of cases
In perforating granuloma annulare, there are grouped papules, some of which have a central umbilication with scale
The extremities are the most common site
A high incidence of perforating granuloma annulare has been reported in Hawaii. It is rare in infants and young children
In subcutaneous (or deep) granuloma annulare, deep dermal or subcutaneous nodules are found on the lower legs, hands, head, and buttocks
These lesions are associated with superficial papules in 25% of cases.

Front 6

Granuloma annulare: Additional Clinical

Back 6

Females are affected more than twice as commonly as males.
The localized and deep forms are more common in children and young adults
Generalized granuloma annulare occurs most frequently in middle-aged to elderly adults
Patients with the generalized form of the disease show a significantly higher frequency of HLA-BW35 compared with controls and with those who have the localized form of the disease
Most cases of granuloma annulare are sporadic but familial cases have occasionally been reported
Lesions of granuloma annulare have a tendency to regress spontaneously; however, about 40% of cases recur
In the generalized form, the clinical course is chronic with infrequent spontaneous resolution and poor response to therapy
The etiology and pathogenesis of the skin lesions in granuloma annulare remain uncertain

Front 7

Granuloma annulare: Histopathology

Back 7

One or more areas of necrobiosis, surrounded by histiocytes and lymphocytes, are present in the superficial and mid dermis
The peripheral rim of histiocytes may form a palisaded pattern
A perivascular infiltrate of lymphocytes and histiocytes is also present; eosinophils are found in 40–66% of cases but plasma cells are rare
The central necrobiotic areas contain increased amounts of connective tissue mucins which can be demonstrated with colloidal iron and Alcian blue
Heparan sulfate is present in addition to hyaluronic acid
The epidermal changes are generally minimal

Front 8

Necrobiosis lipoidica: Clinical

Back 8

The legs (shins) are most common (also forearms, hands, and trunk)
-3/4 are bilateral
-Often multiple (can be single)
-Females > males (3 to 1)
-Start as red papules which become patches or plaques with an atrophic, slightly depressed, shiny yellow-brown center and a well-defined raised red to purplish edge
-Some resolve spontaneously
-many are persistent and chronic and may ulcerate
-Related to DM

Front 9

Necrobiosis lipoidica: Histopathology

Back 9

-Involve the full thickness of the dermis and often the subcutis
-In active chronic lesions the characteristic changes are seen at the edge of the lesions
-Involve most of the dermis but particularly its lower two-thirds
-Histiocytes, including variable numbers of multinucleate Langhans or foreign body giant cells, outline the areas of necrobiosis
-Variable amount of dermal fibrosis and a superficial and deep perivascular inflammatory reaction which includes plasma cells
-Dermal changes extend into the underlying septa of the subcutis and into the periphery of fat lobules
-"Layer Cake" pattern

Front 10

Variants of Granuloma Annulare (Histology)

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1. Generalized

2.Perforating GA-Associated with overlying hyperkeratosis

3. Subcutaneous GA- children, scalp or forehead

4. Incomplete/Interstitial- has interstitial histiocytic infiltrate with minimal or absent palisading OR increased mucin

Front 11

GA vs. necrobiosis lipoidica

Back 11

1. NL has little or no normal dermis between granulomatous foci

2. NL has minimal or no mucin

3. NL likely to have plasma cells

4. NL Individual granulomas are less discrete

Front 12

Necrobiotic Xanthogranuloma: Clinical

Back 12

-Smooth yellow papules on periorbital, head, neck, upper truck
-Most associated with paraproteinemia or cryoglobulinemia

Front 13

Necrobiotic Xanthogranuloma:
Histopathology

Back 13

-Broad zones of degenerating or necrobiotic
-Surrounded by palisades of histiocytes
-Includes Touton giant cells
-Involves dermis and often subcutis
-Cholesterol clefts somtimes present
-Plasma cells and reactive lymphoid follicles may be present

Front 14

Necrobiosis Lipoidica vs. Necrobiotic Xanthogranuloma

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-NXG has more promient necrobiosis
-NXG more Touton giant cells
-NXG has larger, more atypical histiocytes
-NXG can have cholesterol clefts

Front 15

GA versus Rheumatoid nodule

Back 15

-GA has mucin in center of granulomas
-Rhem nodules have fibrin in the center