Generality

Syphilis (or lue) is a disease caused by a bacterium ( Treponema pallidum ), which causes a chronic progressive infection with potential permanent damage to all organs.

The man contracts this pathology above all through sexual intercourse not protected by condoms, both genital and oral, with a previously infected person.

The appearance of the first symptoms of syphilis in male subjects occurs after three to four weeks after infection, with the development of ulcers or round wounds at the point of inoculation of the pathogen (ie in the areas that have come into contact with the areas infected of the other person). These lesions are typically associated with the swelling of regional lymph nodes .

Often, the primary syphilitic lesions are located in the genital area, in particular at the level of the penis, the foreskin (portion of skin that covers the glans) or the anus and, if untreated, tend to evolve towards the secondary stage of the disease.

Secondary syphilis occurs about six weeks after the disappearance of the primary lesion (called sifiloma ) with a macular skin eruption on the limbs and trunk, sometimes accompanied by fever, joint pain, fatigue and hair loss.

In the latent period, man does not show any symptoms, but he can still transmit the disease. If healing does not take place, syphilis can develop into the third stage (tertiary syphilis), which can occur even thirty years after the first infection.

The diagnosis of syphilis in humans is based on clinical-anamnestic data, on the microscopic identification of T. pallidum and on the results of serological investigations. Treatment involves antibiotic therapy, while prevention must be carried out by practicing safe and protected sex to reduce the risk of infection.

Note. Syphilis is one of the most important sexually transmitted diseases . Infection can affect both sexes, but men are more frequently affected by the problem.

Causes and risk factors

Syphilis is caused by Treponema pallidum, a spirochete (that is, a spiral-shaped bacterium) that is able to spread easily in the body.

This infective agent is able to penetrate through intact mucous membranes (genital, rectal and oropharyngeal) or damaged skin, so it can be transmitted easily through oral contact and unprotected vaginal and anal sex.

In the absence of adequate treatment, syphilis evolves within weeks or months: this micro-organism migrates through the skin capillaries, then spread to the lymph nodes, where it multiplies to reach levels sufficient to cause clinical disease. Generally, the incubation times of syphilis extend from 2 to 12 weeks.

In subjects with the disease, Treponema Pallidum is found in all body fluids, such as sperm and vaginal secretions. Furthermore, the bacterium is found in the cutaneous, genital and mucosal lesions, including that of the mouth, which occur during syphilis.

Without a timely diagnosis and therapy, a progressive evolution of the disease is possible, which can induce severe permanent damage to multiple organs and systems, such as skin, heart, brain and skeleton.

Contagion

How can humans contract syphilis?

Humans usually contract the disease through unprotected sexual intercourse, whether genital (vaginal or anal) or oral with a person suffering from syphilis.

Other possible modes of transmission are petting (ie the simple contact between genitals) without protection and the exchange of contaminated sexual tools (eg sex toys).

However, the infection can also be contracted non-sexually, through direct contact with wounds or skin and mucosal ulcers, which are formed in areas where the disease mainly occurs (genital, anus, mouth, throat or skin surface damaged). In some cases, some of these manifestations are painless or go unnoticed, so humans may not be aware of being infected with syphilis, thus risking infecting their partner.

Occasionally, the disease can be transmitted through blood transfusions (a rare form of infection).

In the case of the congenital form, the passage of the bacterium by transplacental route from the infected mother to the child (maternal-fetal transmission) is also possible.

Syphilis does not confer immunity against subsequent reinfection; this means that the patient who has recovered from the disease can contract the infection over and over again in the course of his life.

Symptoms

The natural course of untreated syphilis follows four evolutionary stages:

  • Primary syphilis;
  • Secondary syphilis;
  • Latent syphilis;
  • Tertiary syphilis.

In any case, the disease is complex and, if not properly treated, can lead to various complications, such as heart disease and neurological disorders, up to death.

Primary syphilis in humans

The initial stage of the infection occurs after about 3-4 weeks from the infection, with the appearance of a localized papular lesion, rosacea, circular and with net margins ( syphiloma ) at the inoculation point of Treponema pallidum .

Penile ulcer (syphiloma) caused by syphilis. See More Photos Syphilis

In humans, the most frequent localization of the syphiloma is the scrotal skin, the balano-preputial groove, the outlet of the urethra on the penis and the region around the anus ; less often, this lesion can appear on the skin of the hands or inside the oral cavity, therefore on the lips, gums, pharynx or tongue. Sifiloma does not generally cause pain, but is typically associated with an increase in the volume of regional lymph nodes, which are not, however, painful on palpation.

Within a short time, the surface of the sifiloma tends to ulcerate, exposing a bright red background, from which a serous exudate comes out, containing the treponemes.

Symptoms of the first stage of syphilis in humans generally persist for a variable period between 2 and 6 weeks. In the absence of treatment, syphilis evolves in the secondary phase.

Secondary syphilis in humans

Secondary syphilis begins 3-6 weeks after the onset of syphiloma. This phase is characterized by a macular eruption spread in one or more areas of the body surface, associated with the swelling of the lymph glands . This manifestation is transient or recurrent and can have a very variable appearance: for example, roundish cracks may appear on the palms of the hands and on the soles of the feet, or groups of pink spots spread on the trunk and limbs, which recall the rash of measles.

Secondary syphilis in a woman with a history of unprotected sexual intercourse. Involvement of the sole of the foot

Furthermore, at this stage, the man with syphilis manifests systemic flu-like disorders due to the proliferation and spread of blood by Treponema pallidum . In particular, may appear: fever, asthenia, headache, muscle pain and general malaise.

Syphilis in humans can also lead to sore throat, lack of appetite, weight loss, visual disturbances, hearing and balance disorders, bone pain, hair loss in the hair and appearance of thick, gray or pink skin patches ( warts).

In humans, a rarer form of syphilitic manifestation is an intense balanoposthitis (inflammation of the glans and foreskin), apparently determined by other infectious agents.

Latency period

At the end of the secondary stage, a long latency period begins, which can last months or even years. This phase is due to the immune control of the disease: the man with syphilis has no symptoms, but the infection persists.

Tertiary syphilis in humans

After many years (generally after about 10-25 years from the time of infection), syphilis progresses to the tertiary phase.

At this stage, the disease is characterized by the formation of painless nodes ( lactic gums ) in the skin or brain, bones and joints, and by the serious impairment of the internal organs of the body (including the liver, kidneys, lungs and heart).

Once syphilis enters the third stage, the individual may present with personality alterations, gradual blindness, dementia, inability to control muscle movements and progressive paralysis. In severe cases, syphilis leads to the death of the patient.

The evolution of syphilis can be accelerated by a coexistent HIV infection ; in these cases, eye involvement, meningitis and other nerve complications are more frequent and severe.

Diagnosis

The diagnosis of syphilis in humans can be formulated with the evaluation of the signs and the set of symptoms reported by the patient during a thorough medical examination, and by microscopic observation of the material taken from the lesions (which allows to recognize the treponemes ).

To support these investigations, it is also indicated the execution of blood tests to detect the possible presence of antibodies against the bacterium already in the early stages of the infection, taking into consideration that these appear in a period that varies from 2 to 5 weeks.

These analyzes are essentially divided into:

  • Non-specific tests for Treponema - including the Venereal Disease Research Laboratory (VDRL) - aimed at identifying a lipoid antigen deriving from the bacterium or its interaction with the host; these investigations can offer an advantage with regard to disease control.
  • Treponemic tests, such as the passive agglutination test for treponemal particles (TP-PA) or the fluorescence for the detection of absorption of anti-treponemal antibodies (FTA-ABS); these tests allow to establish the degree of activity of the infection, therefore defining the most appropriate therapeutic protocol for the case.

If the man is infected, all the sexual partners of the previous 3 months (in case of verified primary syphilis) or of the previous year (in case of ascertained secondary syphilis) will have to be evaluated and treated.

Treatment

The treatment of syphilis in humans involves the administration of penicillin parenterally.

In patients allergic to this active ingredient you can resort to other drugs, such as doxycycline and tetracycline.

To establish the correct dosage and duration of antibiotic therapy, the doctor will rely on the stage of the disease defined during the diagnostic procedure. Timely treatment allows the regression of lesions and the prevention of secondary or tertiary syphilis, but any permanent damage to the organs tends to persist.

During drug treatment, to avoid infecting your partner, abstinence from any type of sexual intercourse is mandatory, up to the complete recovery of lesions caused by syphilis. In fact, it must always be remembered that wounds and skin ulcers can transmit infection even during oral sex or any other skin contact with the infected areas.

Prevention

As for the prevention of syphilis, a good measure is the correct use of the condom, which must be used from the beginning to the end of sexual intercourse (whether vaginal, anal or oral) and to protect also any objects used during intimate contact.

Furthermore, it is possible to avoid exposing oneself to the risk of infection by refraining from sexual practices with potentially infected people, and reducing the number of partners.