Foreign bodies in granulomatous cutaneous lesions of patients with systemic sarcoidosis.

Objective: To assess the presence of foreign material in the granulomatous cutaneous lesions of patients with systemic sarcoidosis.

Methods: Observational study reevaluating histological specimens at a university referral hospital. Methods: Sixty-five patients diagnosed as having sarcoidosis who developed granulomatous cutaneous involvement. Methods: To detect the presence of polarizable foreign particles in cutaneous biopsy specimens and to evaluate the association with clinical features of the patients.

Results: Granulomatous cutaneous involvement was demonstrated in 65 (15.3%) of 425 patients with systemic sarcoidosis. In 14 (22%) of the 65 patients, the cutaneous biopsy specimen showed foreign particles in polarized light. The skin lesions corresponded to 3 different clinical patterns: an admixture of papules and infiltration of previously undetected minute scars (n = 6); scar sarcoidosis (n = 4); and subcutaneous nodules (n = 4). The lesions were located most frequently in the extremities, involving the knees in 10 patients.

Conclusions: The presence of polarizable foreign body material in granulomatous cutaneous lesions is not infrequent in patients with systemic sarcoidosis. Inoculation of foreign matter from a previous inapparent minor trauma may induce granuloma formation in individuals with sarcoidosis.