Lesions that may be affected:
(1) scar
(2) tattoo
(3) venipuncture site
(4) injection site
(5) site of blunt trauma
The lesions may appear:
(1) erythematous or purple
(2) swollen
(3) tender and/or painful
(4) rarely ulcerated
Biopsy of the lesion will show noncaseating granulomas that are negative for acid fast bacilli, fungi and polarizable material.
The patient may have a history of sarcoidosis, or the skin changes may coincide with the initial presentation.
Other manifestations of sarcoidosis may or may not be present:
(1) bilateral hilar adenopathy
(2) pulmonary lesions and/or change in pulmonary function
(3) organ involvement (cardiac, neurologic, etc.)
(4) elevated serum angiotensin converting enzyme (ACE)
(5) elevated serum lysozyme
(6) hypercalcemia
Differential diagnosis:
(1) foreign body granuloma, including suture granuloma
(2) deep fungal or mycobacterial infection
(3) hypertrophic scar or keloid