Multiple lesions of granuloma annulare following BCG vaccination: case report and review of the literature

A 12-year-old Japanese boy presented with asymptomatic, multiple annular, erythematous, infiltrated lesions on his left upper arm and right knee as well as the lateral side of the right ankle joint. He had noted these erythematous lesions five days after bacille Calmette-Guerin (BCG) vaccination. The lesions gradually enlarged and increased in number. Topical corticosteroid therapy for several weeks failed to improve the lesions. There was no familial history of pulmonary tuberculosis. Physical examination revealed extensively disseminated, round, erythematous plaques and papules. Some plaques showed an annular configuration, varying in diameter from 5 to 45 mm, on his left upper arm, right knee and the lateral side of the right ankle joint (Fig. 1). One month after BCG vaccination, reddish-brown, infiltrated erythema with crusts was observed at the BCG vaccination site (Fig. 2). Tuberculin test showed an erythema with induration measuring 2.5 cm in diameter at 48 h. Routine laboratory tests including complete blood cell count, erythrocyte sedimentation rate and biochemical analysis were within normal limits. Serum glucose level and GhbA(1c), were also normal. Histopathologically, a biopsy specimen obtained from an annular erythematous plaque on the lateral side of his right ankle joint revealed marked pale staining, well-circumscribed degenerated collagen bundles surrounded by palisading histiocytes and lymphocytes in the dermis (Fig. 3). Alcian blue stain was positive among degenerated collagen fibers. An immunofluorescence study revealed IgG and C3 deposits in dermal vessels. These histologic features were consistent with granuloma annulare. Two months later, the margins of the erythematous lesions had spontaneously faded and, within 7 months, had completely resolved. Reddish-brown erythema at the BCG vaccination site had not disappeared.