Secondary syphilis presenting as a palisading granuloma

The immunopathobiology of syphilis: the manifestations and course of syphilis are determined by the level of delayed-type hypersensitivity

Syphilis has plagued mankind for centuries and is currently resurgent in the Western hemisphere. Although there has been a significant reduction of tertiary disease and recognition of facilitative interactions with human immunodeficiency virus infection, the natural history of syphilis has remained largely unchanged; thus, new strategies are required to more effectively combat this pathogen. The immunopathologic features of experimental syphilis in the rabbit; the course, stages, and pathology of human syphilis; and a comparison of human syphilis with leprosy suggest that the clinical course of syphilis and its tissue manifestations are determined by the balance between delayed-type hypersensitivity (DTH) and humoral immunity to the causative agent, Treponema pallidum. A strong DTH response is associated with clearance of the infecting organisms in a well-developed chancre, whereas a cytotoxic T-cell response or strong humoral antibody response is associated with prolonged infection and progression to tertiary disease. Many of the protean symptoms/appearances of secondary and tertiary human syphilis are manifestations of immune reactions that fail to clear the organism, due to a lack of recruitment and, more importantly, activation of macrophages by sensitized CD4 T cells. The Bacillus Calmette-Guerin vaccination can enhance DTH and has been shown to produce a low, but measurable, beneficial effect in the prevention of leprosy, a disease that shows a disease spectrum with characteristics in common with syphilis. In the prevention of syphilis, a potential vaccine protective against syphilis should be designed to augment the DTH response.

Long-term undiagnosed syphilis with clinical presentation of meningitis

A 43-year-old woman, with an 11-year history of progressive cutaneous lesions, was considered to have granuloma annulare and was treated as such for 4 years. She then developed chronic meningitis. Serological investigation revealed active syphilis. Appropriate antibiotic treatment led to a rapid resolution of the clinical symptoms. The recent reports of similar cases indicate the importance of an adequate knowledge of clinical manifestations and pathological patterns of syphilis.

Necrobiotic granulomas localised to the penis: a possible variant of subcutaneous granuloma annulare

Three young men developed multiple firm asymptomatic nodules confined to the shaft of the penis. Skin biopsies from all 3 cases showed prominent necrobiotic granulomas indistinguishable from granuloma annulare. One of the patients had repeated recurrent nodules confined to the penis which were removed surgically over a period of 20 months. This unusual, but benign, presentation of granuloma annulare has to be distinguished from other granulomatous and malignant processes which may present as penile nodules.