Syphilitic Gummas Mistaken for Liver Metastases

Abstract

occurs years after the initial infection, and is characterized by a chronic inflammatory response to the organism in sanctuary sites. Gummatous syphilis is a type of tertiary syphilis caused by a delayed hypersensitivity reaction to the Treponema pallidum organism. 3 A gumma is a granuloma, histologically characterized by a central area of necrosis surrounded by mononuclear, epithelioid, and giant cells, and ranging in size from microscopic to several centimeters. 3 Spirochetes only rarely are identified in pathologic specimens, and diagnosis instead relies on serologic testing as well as therapeutic response. The incidence of hepatic involvement ranges from 0.9% to 16% in autopsy studies. 4 Gummas may be visible on CT imaging as low-attenuation lesions with slight peripheral enhancement and rare calcifications, which is an appearance that may be confused with metastatic cancer or an abscess. 5 Treatment for gummatous syphilis without neurosyphilis consists of intramuscular penicillin G for 3 weeks; if neurosyphilis is present, as in our patient, administration of intravenous penicillin may be necessary. 6