1 Definition 
2 Pathogen 
Treponema pallidum is a bacterium belonging to the spirochete family, with a length of 7-20 micrometers. Humans are the natural host of treponema pallidum. There are no other known hosts of the virus.
3 Epidemiology 
Syphilis is endemic worldwide.
After the introduction of penicillin in Germany, the incidence of syphilis sank remarkably. After the decrease, the number of new infections remains nationwide constantly at approx. 1100 new cases per year. However, the number of new infections has risen again since 1997. Especially homosexual men in big cities are affected. Current epidemiological data is available on the web pages of Robert Koch Institut
The detection of Trepanoma pallidum is notifiable.
4 Transmission 
The transmission of syphilis necessitates close body contact. Every kind of contact with a mucous membrane can effect its transmission. The most frequent way of transmission is (heterosexual or homosexual) intercourse. Syphilis can also be transmitted by oral intercourse and kissing. The bacterium can also be transmitted through bruised skin, transplacentally and by blood donation.
5 Pathology 
The incubation period ranges from 10 days to 3 months. Syphilis can be clinically classified in 3 stages.
5.1 Stage1 
Characteristic of the primary stage is the ulcus durum developing at the place of entry of the virus. This is a painless, hard-edged ulcer, approximately 2 cm in diameter, which heals as a rule within 3-7 weeks leaving scars.
Following the ulcus durum, the local lymphatic node starts to swell. This swelling remains for some time, even after the ulcus durum has healed. The combination of ulcus durum and swelling of the local lymphatic node is termed the primary complex.
5.2 Stage 2 
In the secondary stage, syphilis manifests in a great number of skin irritations and other symptoms.
- Exanthem: An exanthem with small blotches occurs on the trunk and on proximal parts of the extremities.
- Swelling of the lymphatic nodes: The lymphatic nodes are generally swollen.
- Condylomata lata: Moist skin rashes occur between fingers and toes, under the breast and on the genitals.
- Mucosal papules: Infectious papules occur on mucous membranes.
Another course of the disease in the secondary phase of syphilis is the latency. Latency is the time after the healing of the ulcus durum, when no symptoms are present.
- Early latency: No symptoms exist up to 4 years after contracting the disease. During this phase, the patient must be considered as contagious.
- Late latency: The time without symptoms after early latency. During this phase the patient is not considered contagious. However, in the period of late latency, transmission can still occur by blood donation and transplacentally, since it cannot be ruled out that the viruses continue to circulate in small quantities in the blood stream.
At any given time, both phases of latency can be interrupted by the occurrence of symptoms of stages 2 and 3.
5.3 Stage 3 
The interruption of latency marks the tertiary stage of syphilis. In the tertiary stage, diseases of interior organs occur, e.g. hepatitis, aortic aneurysm and orchitis. Lesions characteristic of the tertiary stage are gumma, mostly in bones and skin.
5.4 Congenital Syphilis (lues connata) 
From the 4th month of pregnancy, a transmission from the mother to the child is possible. A treatment of the mother before this critical date can prevent a transmission.
In the early stage of congenital syphilis, symptoms appear before the completion of the first year. Symptoms include hepatomegaly, splenomegaly and pemphigus syphiliticus. </br> In the late stage, symptoms occur after more than 4 years from birth. Disturbances of growth, deafness and Hutchisonâ€™s triad can occur.
6 Diagnostics 
Sophisticated serological examinations are available for the diagnostics and monitoring of syphilis.
- The TPPA test is used for screening. It provides positive results 2 weeks after infection.
- In case of positive TPPA test, the FTA-ABS test is undertaken to verify the diagnosis.
- The VRDL test is used to monitor the beginning and completion of therapy.
- In case of suspected neurosyphilis, the ITPA index has to be determined. In this test, the titers of antibodies detected in the serum are set in relation to those detected in the cerebrospinal fluid.
7 Therapy 
Syphilis can be successfully healed by antibiotic therapy. Best option for treatment is penicillin G. The therapy must take place with high dosage over a period of two weeks. After completion of therapy, a monitoring is undertaken at regular intervals with VDRL tests and titer determination in the TPPA test.
8 Links 
To comment on this article, please login..