title: Rectal syphilis mimicking histiocytic lymphoma.
abstract: Homosexuality is being recognized with increasing frequency in the United States, and the physician must be knowledgeable of the presentations of venereal infection in this population. A 23-year-old man who denied homosexuality presented with a rectal mass and diffuse adenopathy. Biopsy of the mass was interpreted as histiocytic lymphoma. Subsequent serology had positive results for syphilis. Further questioning revealed a history of anorectal intercourse, and special stains of the mass revealed spirochetes. Syphilis must be considered in any young patient presenting with a rectal mass, regardless of the biopsy histologic characteristics or sexual history.
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D006716:Homosexuality; D006801:Humans; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology*; D008297:Male; D012002:Rectal Diseases / Q000382:microbiology / Q000473:pathology*; D012004:Rectal Neoplasms / Q000473:pathology; D013587:Syphilis / Q000382:microbiology / Q000473:pathology*