Syphilis is a highly infectious, chronic STD characterized by lesions that may involve any organ or tissue. After a brief decline in cases in the late 1990s, cases have again begun to rise.
Syphilis is caused by the bacterium Treponema pallidum. The bacteria are transmitted via direct contact with infected lesions, typically through vaginal, oral, or anal sexual intercourse or through contact with infected bodily fluids. Syphilis also may be contracted as a consequence of transfusion with infected blood (a rare occurrence). In pregnant females, T. pallidum can cross the placenta and infect the fetus, causing serious fetal damage. The bacteria rapidly penetrate skin or mucous membranes. From the point of infection, they spread into the lymphatic system and the blood, producing a systemic infection. Typically, the bacteria will have been carried throughout the body long before the first clinical symptoms appear.
Signs and Symptoms
When untreated, syphilis typically progresses through three clinical stages, each with characteristic signs and symptoms. Note, however, that some infected individuals are asymptomatic or present with symptoms that are not readily evident on casual inspection.
Primary syphilis, which has an incubation period of about 3 weeks, is characterized by the appearance of a distinctive, red, ulcerated, painless lesion, called a chancre, at the point of infection. In males, the chancre typically appears on the penis. The chancre also may appear on the anus or within the rectum. Among females, the lesion typically appears on the labia of the vagina or within the vagina or cervix. Among both males and females, chancres also may appear on the lips, tongue, fingers, or nipples. The appearance of the chancre also may be accompanied by regional lymphadenopathy, a disease of the lymph nodes, usually manifested as swelling of the nodes. It must be emphasized that the chancres are highly contagious. During this stage, the chancre usually heals within 3 to 12 weeks without treatment.
Secondary syphilis can produce a host of symptoms, many of which may be mistaken as symptoms of other diseases. Most frequently, however, individuals at this stage of the disease present with a rash characterized by uniform macular, papular, pustular, or nodular lesions. These typically, but not exclusively, appear on the palms or soles. In moist areas of the body, these lesions can erode and become contagious. Various general or systemic manifestations, including headache, malaise, gastrointestinal (GI) upset, sore throat, fever, patchy hair loss, and brittle nails, may accompany the rash. This stage generally lasts 3 to 6 months. After the manifestations of secondary syphilis subside, a latent stage of the disease begins in which the infected individual is generally asymptomatic.
The bacteria may remain latent indefinitely. In roughly half of untreated individuals with latent syphilis, manifestations of the final, or tertiary, stage of the disease begin to appear 2 to 7 years after the initial infection. However, some cases may not appear until 20 years after the initial infection. In tertiary syphilis, the Treponema bacteria may cause life-threatening damage to the aorta of the heart, the central nervous system, or the musculoskeletal system; no organ system is immune from damage. Consequently, the symptoms of tertiary syphilis mimic the symptoms of other organ system diseases, making diagnosis difficult.
The most sensitive test available for detecting syphilis is the fluorescent treponemal antibody-absorption (FTA-ABS) test. A rapid plasma reagin (RPR) test or a Venereal Disease Research Laboratories (VDRL) test also may be performed.
Penicillin, intramuscularly or IV, is the antibiotic of choice for the treatment of all stages of syphilis. Doxycycline may be used in the event of allergic reaction to penicillin. Any lesions should be kept as dry and clean as possible. An RPR or the VDRL test typically accompanies the drug therapy to ensure the Treponema bacteria have been eradicated.
There are no complementary therapies that will kill the bacterium.
The use of condoms is highly recommended. Clients are encouraged to limit and know their sexual partners as well as their partners’ sexual history. Regular screening for STDs is recommended for those persons at risk.
The prognosis varies with the age of the affected individual and with the stage at which the disease is detected and treated. The prognosis for complete recovery is very good for adults treated for primary and secondary syphilis. Although tertiary syphilis also can be successfully treated, any organ system damage that may have occurred to that point is generally irreversible. Untreated, the disease may lead to life-threatening cardiac, central nervous system, or musculoskeletal disorders. The prognosis is poor for a fetus infected with syphilis, with spontaneous abortion or stillbirth occurring in nearly 20% of cases.
The use of condoms during sexual intimacy can reduce the possibility of transmitting or acquiring syphilis, but contact tracing of intimate partners and serologic screening remain the most important methods in limiting the spread of this disease. Sexual partners should be evaluated and treated even if they show no symptoms.