Syphilis Infectious disease caused by the spirochete Treponema pallidum. Penetrates broken skin or mucous membranes. Transmission by sexual contact. Congenital syphilis can be transmitted to the fetus during any stage in pregnancy. Syphilis is widespread in the United States and primarily involves sexually active adults between years of age.

Stains used for bacterial identification Grams stain Silver stains Dark field microscopy Imuunoflorescence

Syphilis has three stages Primary syphilis Painless sores, called chancres, appear approximately 2-3 weeks after initial exposure Single firm, non tender, raised red lesion located at the site of treponemal invasion on the penis, cervix, vaginal wall or anus. Chancre heals in 3-6 weeks without therapy. Numerous spirochetes in the chancre seen by dark field microscopy immunoflorescent stains Hematogenous and lymphatic spread of the organism Approximately one-third of untreated individuals will progress to the second stage.

Secondary syphilis Occurs at about 2 to 10 weeks after the appearance of the primary chancre. Occurs due to spread and proliferation of the spirochetes within skin and mucocutaneous tissues. Secondary syphilis is the stage where the bacteria have spread in the bloodstream and have reached their highest numbers.

skin rash involving the palms and soles – Maculopapular,scaly or pustular Silvery erosions- in the mouth, pharynx and external genitalia. Moist areas of skin- anogenital region,axilla- Condylomata lata- broad based elevated plaques. All lesions very infectious so most contagious stage. Swollen lymph node and fever also common Symptoms last for several weeks

Tertiary syphilis Occurs after a latent period of 5years. Characterized by brain or central nervous system involvement (neurosyphilis), cardiovascular involvement with inflammation of the aorta (aortitis or aneurysms), and gummatous syphilis (destructive lesions of the skin and bones).

Symptoms Depend on the stage of the disease. Some individuals may remain without symptoms. Primary syphilis Chancres -- (usually single yet may be multiple) painless sores on genitals, rectum, or mouth Enlarged lymph node in the area adjacent to the chancre Histopathology shows treponemes on the surface of ulcer, plasma cell infiltration and obliterative endarteritis

Secondary syphilis: skin rash –palms and soles extensive lymph node enlargement mucous patchespatches condyloma lata Histopathology- plasma cell infiltration,obliterative endarteritis but inflammation less than primary syphilis

Tertiary syphilis Aortitis- endarteritis of vasa vasorum Narrowing of coronary artery ostia General paresis Tabes dorsalis Gumma- grey white rubbery masses is skin, subcutaneous tissue, bones and joints. -centre of coagulated necrotic material with palisaded macrophages, fibroblasts and plasma cells

Congenital syphilis Treponema crosses placenta Usually primary or secondary syphilis Early manifestations- <2 years nasal discharge,snuffles,hepatomegaly and skeletal abnormalities and saddle nose. Late manifestations- Hutichinson triad notched central incisors,interstitial keratitis and deafness.

Serological tests Nontreponemal antibody tests- RPR, VDRL positive 4 weeks after infection and later negative screening tests biological false positives- drugs,SLE,pregnancy Antitreponemal antibody tests- FTA-Abs, MHATP positive 4 weeks after infective and then remain positive specific tests Dark field examination of primary lesion (in primary syphilis)