LAUSR

© BMJ Publishing Group Limited 2022. No commercial reuse. See rights and permissions. Published by BMJ. DESCRIPTION A woman in her 30s presented to the emergency department with extremely painful confluent ulcerated lesions of the perineum (figure 1) and inguinal fold (figure 2). The ulcers were gelatinous and partially covered by a yellowish exudate. She reported indolent evolution of the lesions over the past 3 months, with fluctuating intensity of pain and burning symptomatology, without regression of the lesions. She had been treated with topical steroid therapy and antibiotics without improvement. She denied other symptoms such as fever, malaise or weight loss. She was previously healthy and reported casual unprotected sexual intercourse, more than 3 years ago. She denied history of sexually transmitted infections, intravenous drug use, contact with animals or recent travel abroad. Differential diagnosis may be considered: primary syphilis usually begins with a single, painless, welldemarcated ulcer with a clean base and indurated border. Herpetic ulcers (the most prevalent cause) are painful and usually last 7–10 days. Behçet’s disease and Lipschutz ulcers were also considered, but the patient had no history of other mucosal ulcerations or systemic disease. Punch biopsy of the lesions showed significant inflammatory infiltrate with suppuration and serological tests came back positive for syphilis (VDRL Venereal Disease Research Laboratory positive) and negative for hepatitis B and C and HIV and the diagnosis of tertiary syphilis was established. She was treated with three doses of 2.4 million units of benzathine penicillin G intramuscular injections during the course of 3 weeks. The lesions showed significant improvement after the first dose of treatment and were completely healed at the end of treatment (figure 3). According to the WHO, 12 million new cases of syphilis are reported per year worldwide, with only 10% of cases occurring in developed countries.