More than 5 million new cases of syphilis are diagnosed worldwide each year, most of which occur in low-income countries where both endemic and uncommon congenital cases are found. Those affected also include ordinary travelers who engage in different sexual behaviors during vacations or business trips, bringing with them upon their return pathologies for which they were not prepared. In low- and middle-income countries, syphilis infection is a relatively common disease that is a source of substantial morbidity, including adverse pregnancy outcomes and accelerated HIV transmission. In high-income countries, syphilis is largely transmitted within close sexual and social networks. Although the disease is relatively rare, more than 15-20% of the U.S. population diagnosed had been infected well before diagnosis.
Although syphilis is a chronic infectious disease that could cause morbidity throughout its natural history, the infection is transmissible (with the exception of congenital infection) only early in its course. For this reason, public health focuses its efforts on the primary, secondary, and latent stages of the infection, also referred to as infectious syphilis. After two or three years without any treatment, infection is rarely transmitted sexually, but its range shifts to personal morbidity, resulting in late neurosyphilis and cardiovascular infections.
First stage
In primary syphilis, the main clinical manifestation is the presence of an ulcerated lesion that typically appears about 2 to 3 weeks after direct contact with an infected lesion. Although these lesions are most often seen in men on the distal penis, they can be located at almost any site where direct contact with the infected person's lesion might occur and, although sometimes unnoticed, are well described in the vagina and female cervix, in and near the rectum, in the mouth, as well as on other potentially exposed body parts such as the fingers and neck. Genital ulcers mimicking tumors are most commonly caused by genital herpes, but can be caused by chancroid, trauma, fixed drug eruptions, and dermatologic processes. Without treatment, after a period of 3-6 weeks, primary lesions resolve spontaneously without leaving scars. With treatment, the lesions begin to resolve within a few days.
Second stage
Secondary syphilis is the most commonly recognized clinical syndrome of this infection, particularly among women or MSM, and it is traced to the lack of treatment of the internal vaginal or anogenital lesions that occurred during the first stage. The classic manifestations of secondary syphilis are:
- the rash, which is extraordinarily variable in appearance but is generally macular and papular, painless, 1/2 cm, reddish or copper-colored, and may involve the face, trunk, limbs, and sometimes the mucous membranes;
- lesions on the palms of the hands or soles of the feet, here not papular in character but infiltrative, a peculiarity that highlights and recognizes syphilis from other eruptions.
In about one-third of patients with secondary, Condylomata Lata may occur in the genital and perianal region where flat condylomata develop, which are typically warty and papillomatous and are identified as eroded grayish plaques with a foul odor. After resolution of second-stage onset, untreated syphilis enters a latent phase in which clinical manifestations are absent and can be detected only by serologic testing.
Third stage
Latent syphilis is further divided into early and late latent syphilis, a differentiation that influences treatment decisions and partner notification recommendations. Based on observations from the Oslo study of untreated syphilis in the early 20th century, within a year or two of resolution of secondary manifestations of infection, about 25 percent of untreated persons will have recurrent secondary manifestations and thus once again be potentially infectious to sexual partners. Most of the recurrent clinical manifestations in early latent syphilis occur during the first year of latency. After a period of years or even decades, based on data from the preantibiotic era, about 1/3 of people with untreated latent syphilis will have further clinical manifestations such as late neurosyphilis, cardiovascular syphilis, or gummy syphilis. Cardiovascular syphilis most often manifests as ascending aortic aneurysm formation, aortic valve insufficiency, or coronary artery disease.
Neurological involvement in syphilis
Neurosyphilis is a dreaded but poorly understood complication of infection that can occur at any time during the course of infection. Abnormalities of T. pallidum and cerebrospinal fluid (CSF) can be detected in the CNS (Central Nervous System) in a substantial proportion of patients with early syphilis, many of whom have no obvious neurological signs or symptoms.The importance of invasion and its impact on therapeutic decision making, particularly in the early stages of infection, remains a subject of ongoing debate and research. Clinical neurosyphilis can manifest in a variety of ways that are roughly related to the duration of infection, although some findings such as ocular involvement can occur throughout the course of untreated syphilis. Some individuals with secondary syphilis may present with an aseptic meningitis syndrome of headache and mild meningism (syphilitic meningitis).Recognition of meningovascular syphilis, in relatively young people who present with premonitory signs or symptoms of meningovascular syphilis, provides an opportunity for treatment to prevent additional and irreversible neurological deficits due to stroke. The most common manifestations of meningovascular syphilis are hemiplegia, aphasia, or seizures related to involvement of the middle cerebral artery or its branches.
Therapy is antibiotic and is based on:
- Long-acting benzathine penicillin
- Azithromycin
- Ceftriaxone
Effective therapy tends to be based on early identification of the disease.
There are currently no vaccines available against syphilis although the global nature of the public health problem posed by this infection suggests that a vaccine could target populations of all income targets.
Prevention and control of syphilis by national, state, and local public health agencies include disease surveillance, epidemiologic analysis, education of providers and the public, support for clinical and preventive services, outreach to diagnose recent patients and their sexual partners, and screening of persons at high risk for infection.
Screening means, the evaluation of the presence of a disease in people without signs or symptoms of that disease; unfortunately, such programs are not articulated in the Italian territory. The test is usually performed on people who have reported signs or symptoms.