Multiple skin ulcers from malignant syphilis

Abstract

A 38-year-old man presented to our department in April, 2014, with a 1 month history of multiple painful skin ulcers (fi gure) on his face, trunk, and extremities. The eruptions had started as papular and nodular lesions and progressed to pustules and painful ulcers within 2 weeks. He had been diagnosed with pyoderma gangrenosum at his local hospital and treated with methylprednisolone. After 1 week, the lesions had worsened and he had developed fever. He reported having had sex with four women during the past year and denied ever having sex with men. Histological examination of a biopsy sample from an ulcer on his left arm indicated psoriasiform epidermal hyperplasia with central ulceration. In the dermis we noted mixed perivascular infi ltrate with neutrophils, lymphocytes, plasma cells, and histiocytes. Stains for fungi, mycobacteria, and spirochetes were negative. Full blood cell count, CD4 cell count, CD8 cell count, anti-neutrophil cytoplasm antibody test, HIV serotest, and cultures for fungi and bacteria (including Mycobacterium tuberculosis and Neisseria gonorrhoeae) were normal or negative. The erythrocyte sedimentation rate (ESR) was 50 mm/h (normal range 0–20 mm/h). Serum treponema pallidum particle agglutination assay (TPPA) was positive and rapid plasma reagin (RPR) titre was 1:128. On the basis of clinical examination, serum TPPA, RPR, and histological examination, we diagnosed malignant syphilis. We started 2·4 mg intramuscular benzathine penicillin injections, once a week for 3 weeks. 6 months later the ulcers had healed completely, although atrophic scars remained (fi gure); the RPR titer dropped to 1:1 and HIV serotest remained negative. Malignant syphilis is a rare form of destructive secondary syphilis. It usually occurs from 6 weeks to 1 year after primary infection, or earlier in people with HIV. Syphilis is a common sexually transmitted disease in China, with an incidence of 0·03% in 2014. However, malignant syphilis is rare.