3.3 Granulomatous, metabolic and depositional diseases

Question 1

4 types of GA?

Answer 1

1. Patch GA (macular) - patches of erythema over extremities, trunk
2. Generalized GA (disseminated) - flesh colored pink papules over trunk/extremities, a/w diabetes
3. Perforating GA - small papules with central umbilication and crustingtypically over dorsal hands
4. Subcutaneous GA - deep dermal nodules similar to rheumatoid nodules; typically asymptomatic

Question 2

Path finding to differentiate necrobiosis lipoidica (+/- diabeticorum) from GA?

Answer 2

Horizontal palisading sandwiches and plasma cells

Question 3

What is annular elastolytic giant cell granuloma (actinic granuloma)?

Answer 3

Unclear if distinct disease or if is variant of GA, related to inflammation triggered by actinic damage

Question 4

What is necrobiotic xanthogranuloma?

Answer 4

Rare, multisystem histiocytic disease, p/w red-orange to yellow papules, nodules, or plaques on face (periorbital), tendency toward ulceration, 80% with IgG monoclonal gammopathy

Question 5

Findings of cutaneous Crohn’s Disease?

Answer 5

Genital erythema with swelling, perianal indurated plaque or ulcerations, oral indurated fissuring of lower lip