Syphilis, also called lue, is an infectious disease caused by the bacterium treponema pallidum. Generally, it affects the genital organs but can also cause generalized disorders and manifestations (systemic symptoms) and, under certain circumstances, progress over time (chronic form) and cause irreversible damage to the internal organs.

Known for centuries by the name badly French, syphilis is extremely widespread throughout the world, particularly in the developing countries of Africa and Latin America.

In Italy, after warts, it is the most ascertained sexually transmitted disease (diagnosed) during medical visits or laboratory tests.

The bacterium responsible for the disease, transmitted during sexual intercourse, is able to penetrate through the mucous membranes of the genitals, rectum, mouth and throat (oropharyngeal) causing the appearance of the characteristic pinkish raised lesions (papules) that are not painful ( syphilomas), which generally persist for a few weeks.

In the absence of adequate treatment, the bacterium can spread in the body and cause, after weeks or months, the so-called form secondary of syphilis. At the end of this phase we enter the period in which the disease no longer causes disturbances (latency period): in more than two thirds of cases, this phase is associated with definitive recovery.

After many years, in a small percentage of people, the tertiary syphilis with damage to internal organs (heart, lungs, liver, brain, bones and joints) and to the skin (luetic gums) and severe impairment of the body, with the risk of dementia (neurosyphilis) and cardiac dysfunction.

In addition, transmission of the bacterium from mother to child (congenital syphilis) during pregnancy or childbirth is possible. This is especially the case if syphilis is contracted in the last trimester of pregnancy.

Congenital syphilis of the child may not cause disturbances (be asymptomatic) or lead to impairment of the nervous system, liver and spleen.


Syphilis, in some cases, can develop causing very mild disorders or without causing them at all (read the Bufala) and be discovered only through laboratory tests (latent syphilis).

In the vast majority of cases, 7-90 days after the infection, it appears on the mucous membrane of the genital organs (penis, vulva, vagina) of the anus / rectum, of the mouth (oro-pharynx) and, rarely, on the skin near to the genital organs, the characteristic rosacea papule (syphiloma), which does not cause pain and tends to ulcerate. There is also often the swelling of the nearby lymph glands. These lesions remain for a period of 2-6 weeks and then tend to disappear spontaneously or after adequate antibiotic therapy.

In the absence of treatment, the bacterial infection can reappear after weeks or months, with the presence, at the level of the mucous membranes or on the skin of the chest and limbs, of raised pink spots (papules) accompanied by weakness, fever and swelling of the lymph glands (secondary syphilis). Generally these manifestations disappear after a few weeks without causing permanent consequences and the disease enters a long phase in which it does not cause disturbances (symptomatic latency) and which, in more than two thirds of cases, involves a definitive recovery.

In the asymptomatic phase, the presence of antibodies against syphilis treponema can still be documented, an indication of the immunological memory towards the infection.

After many years, in a small percentage of cases, the involvement of internal organs (heart, lungs, liver, brain, bones and joints) and of the skin (tertiary syphilis) can occur.

In this phase, the disorders (symptoms) may concern the skin (presence of "rubbery" lesions that do not cause pain), the nervous system (irritability, convulsions, delirium, dementia), the cardiovascular system (weakness, signs of heart failure), the bones and joints. The progressive impairment of the central nervous system and the cardiovascular system can lead to death in severe cases.


Syphilis is almost exclusively contracted through sexual intercourse (vaginal, anal and oral-genital) unprotected, from start to finish, by the male or female condom (read the Hoax).

Contagion can also occur through the exchange of sexual tools, contact between the mucous membranes and mutual masturbation (read the Hoax).

The bacterium that causes the disease can also be transmitted from mother to baby (congenital syphilis) during pregnancy or childbirth, especially if the infection is contracted in the last trimester of pregnancy.


The assessment (diagnosis) of syphilis requires direct observation of the papules, ulcers or spots during a specialist medical examination and the performance of specific laboratory tests.

The laboratory analyzes consist in the identification of the bacterium in the lesions (nodules and papules) by microscopy or molecular biology methods and in the search in the blood of antibodies, directed against specific antigens (TPHA, TPPA treponemal tests) and non-specific (non-treponemal tests VDRL or RPR).The presence of specific antibodies in the absence of manifestations suggests an infection contracted in the past or in a latent phase.


Syphilis in the primary phase is mainly treated with high doses of antibiotics derived from penicillin or belonging to other types (tetracyclines, cephalosporins, macrolides).

A cure (therapy) started quickly (timely) allows the disappearance of injuries and disorders in a short time as well as the prevention of secondary or tertiary syphilis. It is advisable that the therapy is followed, in a preventive way, also by the sexual partner.

The treatment of the secondary form is carried out with the same classes of antibiotics used in the primary form.

In the tertiary phase, now much rarer, therapy by mouth or by injection (systemic) with antibiotics capable of penetrating the central nervous system (brain, spinal cord) may also be appropriate. Any damage to other internal organs affected by the infection must be managed in a specialist hospital setting.

Syphilis (or treponema pallidum infection) in pregnancy must be treated with antibiotics that do not harm the unborn child.


Syphilis is prevented with the correct use of a male (condom) or female (femidom) condom during vaginal, anal and oral-genital sexual intercourse. Instruments and objects used for sexual practice should also be protected with a condom.

Women who are pregnant, or who intend to plan it, should exclude the presence of the infection by means of appropriate medical checks and the execution of tests treponemics and non-treponemics.

Living with

Syphilis in active form (primary or secondary), once ascertained (diagnosed) necessarily requires adequate antibiotic therapy capable of promoting the disappearance of the papules and avoiding the progression of the infection.

The progress of the infection must also be followed (monitored) in the following weeks and months by means of specialist medical visits and laboratory analyzes.
Sexual intercourse must be absolutely protected until the complete regression of the injuries and the ascertainment of healing.

If laboratory tests, despite no disorders, show an infection, it is likely that it was contracted in the past and, before being able to have sex without protection, it is necessary to exclude that it is in an active phase.

In the case of advanced tertiary syphilis, specialist checks are essential to check for any damage to internal organs and, if there are serious disorders and manifestations of the disease, with neurological and cardiological complications, hospitalization is required.


World Health Organization (WHO). WHO guidelines for the treatment of Treponema pallidum (syphilis), 2016

Salfa MC et al. Sexually Transmitted Infections: update of the data of the two sentinel surveillance systems active in Italy at 31 December 2014. Newsletter of the "Istituto Superiore di Sanità". 2016; 29: 3 

Salfa MC, Ferri M, Suligoi B and the Sentinel Network of Clinical Centers. Sexually transmitted infections: update of the data of the two sentinel surveillance systems active in Italy at 31 December 2017. Newsletter of the "Istituto Superiore di Sanità". 2019; 32

In-depth link

United Against AIDS (ISS). HIV and other sexually transmitted infections

Ministry of Health. Syphilis

WHO Media center. Sexually Transmittable Infections (English)

EpiCentro (ISS). Syphilis

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