Superimposed primary chancre in a patient with Adamantiades-Behçet's disease.

Adamantiades-Behçet's disease was diagnosed in a 42 year old Turkish patient with recurrent oral aphthae, genital ulcerations, papules, and sterile pustules, histologically presenting as cutaneous vasculitis, and intermittent arthritis with joint effusion particularly of the knees. Six months after initial improvement under treatment with colchicine 2 mg/day, a solitary genital ulcer with enlarged inguinal lymph nodes appeared and persisted for 7 weeks despite the continuation of colchicine treatment and the introduction of clindamycin 2 mg/day intravenously. The unusual persistence of the ulcer and the failure of clindamycin therapy led to further differential diagnostic considerations and the identification of primary syphilis. The genital lesion healed 4 weeks after initiation of treatment with tetracycline 2 mg/day by mouth for 15 days.