DefinitionA gumma is a soft, tumor-like growth of the tissues (granuloma).Causes, incidence, and risk factorsA gumma is caused by syphilis. It appears during late-stage tertiary syphilis. It usually contains a mass of dead and swollen fiber-like tissue, and occurs most often in the liver. It also can occur in the:BoneBrainHeartSkinTestisEyesSimilar-looking sores sometimes occur with tuberculosis.ReferencesTramont EC. Treponema pallidum (Syphilis). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 6th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2005:chap 235.Eckert LO, Lentz GM. Infections of the lower genital tract: vulva, vagina, cervix, Toxic shock syndrome, HIV infections. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM, eds. Comprehensive