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. Design end getting: Observational study reevaluating histological specimens at a university referral hospital. Patients: Sixty-five patients diagnosed as having sarcoidosis who developed granulomatous cutaneous involvement. Main Outcome Measures: To detect the presence of polarizable foreign partic les in cutaneous biopsy specimens and to evaluate the association with clin ical 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 admixtu re of papules and infiltration of previously undetected minute scars (n=6): scar sarcoidosis (n=4), and subcutaneous nodules (n=4). The lesions were l ocated most frequently in the extremities, involving the knees in 10 patien ts. Conclusions: The presence of polarizable foreign body material in granuloma tous cutaneous lesions is not infrequent in patients with systemic sarcoido sis. Inoculation of foreign matter from a previous inapparent minor trauma may induce granuloma formation in individuals with sarcoidosis.