Syphilis: Stages, Symptoms, Diagnosis, and Treatment

Syphilis, commonly known as the French disease, is a systemic infectious disease caused by the entry of the bacterium Treponema pallidum into the body and is most commonly transmitted through unprotected sexual contact. The first and most characteristic sign of this condition is a single painless sore with a hard base and clearly defined edges that appears in the genital area or around the mouth where the bacterium entered the body. Its treatment can be managed with penicillin-group antibiotic injections administered under specialist supervision and planned according to the stage at which the disease is detected. When accurately diagnosed at an early stage and treated with appropriate pharmacological protocols, the progression of this condition can be stopped; however, if neglected, it may silently become chronic and has the potential to cause serious systemic damage throughout the body.

What Is Syphilis?

Syphilis is not merely a problem of the modern age but a long-established disease that has profoundly affected human history and shaped social habits and health policies. When historical records and medical examinations are reviewed, it is believed that the disease was carried from the American continent to Europe after the geographical discoveries of 1492. This process, which began with the return of ship crews, gradually led to its spread across all continents through waves of migration, the expansion of trade networks, and major wars. Because the nature of the disease was not understood at the time, it created great fear and panic among societies.

The effects of the disease during the Ottoman Empire and the measures taken against it are also quite remarkable. Recorded in the medical literature of the period under names such as maraz-ı efrenci, illet-i efrenciye, or Frenk uyuzu, this infection spread seriously throughout Anatolia, especially after the prolonged wars and mass military movements experienced in the 19th century. Faced with this situation, administrators and physicians were forced to take action. Due to the seriousness of the condition, reports prepared by Dr. Michael and Handanyan in 1879 formed the foundation of the first official public health measures that could be considered quite strict under the conditions of that period.

These historical measures aimed to slow the spread of the disease. To prevent transmission, regulations were introduced such as keeping patients under observation in special hospitals, monitoring individuals’ health for a prolonged period before marriage, and preventing personal belongings from being shared with others. Today, despite the availability of antibiotics, syphilis continues to be a condition frequently encountered in urology clinics because of unprotected sexual contact habits and the presence of other infections that affect the immune system.

What Are the Differences Between Gonorrhea and Syphilis?

One of the longest-lasting and most interesting errors in medical history was the belief for centuries that syphilis and gonorrhea were different forms of the same disease. The basis of this misconception lies in a highly dangerous personal experiment conducted in the name of medical science by the English physician John Hunter in 1793. Hunter injected purulent fluid taken from a patient showing symptoms of gonorrhea into his own body and later observed the development of the typical skin sore characteristic of syphilis. Based on this result, he announced that both diseases originated from the same source. However, what Hunter failed to consider was that the patient from whom he took the discharge carried not only gonorrhea but also a hidden syphilis infection.

This deep-rooted misunderstanding was later corrected through detailed clinical observations conducted by a researcher named Benjamin Bell. The symptoms, transmission mechanisms, and effects created in the body by the two diseases are quite different from one another. The bacterium that causes syphilis is generally transmitted from person to person through direct contact of skin lesions or mucous membranes in the infected area with healthy skin. Transmission is mainly focused on contact with a sore.

Gonorrhea, on the other hand, is caused by a completely different bacterium and infects the inner surface of the urinary tract through sexual fluids. There are also significant differences between the transmission dynamics and risk rates of these two diseases. While the probability of gonorrhea transmission during sexual contact with an infected partner is quite high, this rate increases substantially with repeated contact. Due to their anatomical structure, women have a much more pronounced risk of contracting gonorrhea even from a single exposure. Therefore, correctly distinguishing these two diseases in a patient presenting with genital complaints is the most critical step in creating an appropriate treatment plan.

What Symptoms Does Syphilis Cause in the Body?

After the syphilis bacterium enters the body through microscopic cracks in the skin or mucous membranes, it does not react immediately. A silent incubation period occurs, which may vary depending on the person’s immune resistance but usually lasts several weeks. As the disease progresses, different reactions and clinical pictures emerge in the body. Understanding this gradual progression of the disease is very important for increasing the chance of early intervention.

The main stages encountered during the course of the disease are as follows:

• Primary stage
• Secondary stage
• Latent stage
• Tertiary stage

During the primary stage, which is the first phase, a classic sore called a chancre appears at the initial point where the bacterium entered the body. Usually appearing on the external genital organs, around the anus, or sometimes in the mouth, this sore contains certain clues during clinical examination. The edges of the sore are generally sharp, its shape is regular, and its color resembles living tissue. Its most distinguishing feature is that its base feels firm and cartilage-like when touched. The most common reason patients delay seeking medical attention is that this sore usually causes no pain or aching. Shortly after the sore develops, swelling may begin in the lymph nodes in the groin region. These swellings are usually firm lumps that do not hurt when touched and can move under the skin. Even if left untreated, the sore tends to close and disappear spontaneously within a few weeks. However, this appearance of healing is deceptive; during this time, the bacterium enters the bloodstream and begins traveling toward other parts of the body.

In the secondary stage, the disease has now spread throughout the entire body. During this stage, non-itchy reddish skin rashes may appear, usually on the palms of the hands and soles of the feet. In addition, complaints such as broad, flat-based wart-like structures in the genital region, generalized lymph node swelling, mild fever, fatigue, and patchy hair loss may be added to the clinical picture. These symptoms may also regress spontaneously after a while, and the disease then enters the latent, or hidden, stage. In the latent stage, the patient has no physical complaints, and the infection can only be detected through laboratory tests. If the disease remains unnoticed for years, it may reach the much more dangerous tertiary stage. In this final stage, the risk of granulomatous lesions in the organs, damage to the heart valves, and neurological disorders affecting the nervous system increases.

Is Every Sore in the Genital Area a Sign of Syphilis?

Not every sore, swelling, or lesion that develops in the genital area, groin, or perianal region in male or female patients necessarily means syphilis. The issue physicians pay the most attention to in urology and dermatology clinics is examining the nature of these sores and making the correct differential diagnosis. This is because there are many other types of infection that can cause genital sores, and the management of each is completely different. Making this distinction correctly directly affects the patient’s recovery process.

The main other diseases evaluated in the differential diagnosis are as follows:

• Chancroid
• Genital herpes
• Lymphogranuloma venereum
• Granuloma inguinale
• Behçet’s disease

Chancroid is an infection caused by a different bacterium and has a much shorter incubation period compared with syphilis. The sores that occur in this disease are, in complete contrast to syphilis, extremely painful, have irregular edges, and display an ulcerated structure. The base of the sore is soft, and there is usually a layer of purulent discharge over it. The accompanying lymph node swellings are also quite painful and may tend to discharge through the skin over time.

Genital herpes is a viral disease. It is characterized by tiny fluid-filled blisters grouped in clusters on a reddened area of skin. When these blisters rupture, they leave behind painful, stinging, superficial sores. Because the virus has the ability to remain hidden in the nerve roots, these painful sores tend to recur during periods when the person’s immune system is weakened, when they are under stress, or when they are sleep deprived.

In lymphogranuloma venereum, a small sore forms in the genital area, heals quickly, and often goes unnoticed by the patient. The main clinical picture becomes apparent weeks later when the lymph nodes in the groin swell to enormous sizes, cause severe pain, and create tunnel-like structures in the skin called fistulas. Behçet’s disease, on the other hand, is a systemic vascular inflammatory condition that is not caused by infection but progresses with recurrent deep, painful sores in the genital area that leave scars as they heal. The specialist physician approaches the correct diagnosis by evaluating all these different clinical pictures according to criteria such as the appearance of the sore, the patient’s pain status, and the duration of development.

Which Medical Tests Are Used to Diagnose Syphilis?

No matter how carefully the clinical evaluation, patient history, and physical examination of the sore are performed, whether a genital sore is definitively caused by syphilis must be supported by modern laboratory tests. The diagnostic algorithm of the disease operates in a highly planned manner to prevent misinterpretations and direct the patient toward the most appropriate treatment. The timing and type of tests are of great importance in preventing unnecessary panic or overlooked cases.

The main methods used in the diagnostic process are as follows:

• Dark-field microscopy examination
• Nucleic acid amplification tests
• Screening blood tests
• Confirmatory blood tests

Samples taken from a suspicious sore or discharge may be examined in equipped laboratories using special microscopic methods. In this way, the bacterium’s characteristic spiral structure and movement can be observed directly. Today, advanced tests that work by amplifying genetic material also have high accuracy rates for detecting the pathogen in swabs taken from sores.

However, the most commonly used method in clinics is serological blood testing. Blood tests are basically evaluated in two different groups. In the first stage, screening tests are performed to measure the body’s general reaction to tissue damage. If these screening tests give a positive result, confirmatory tests are then performed to look for specific antibodies produced directly against the bacterium causing the infection. To state that the disease is actively continuing, both test groups are generally expected to be positive.

At this stage, there is an important process that physicians and patients must consider, known in medicine as the window period. If a person undergoes a blood test very shortly after suspicious contact, while the sore has only recently appeared, the results may be negative because the body has not yet produced a sufficient level of antibodies. The appearance of normal blood values despite the presence of a sore should not mislead the physician. In such cases, the specialist may recommend repeating the tests a few weeks later to avoid putting the patient at risk. In addition, in people who have successfully completed syphilis treatment, screening tests may return to normal over time, while confirmatory tests may remain positive for many years because of the immune system’s memory. This does not mean that the patient is still infected; it only indicates that the person encountered this bacterium in the past.

Which Methods Are Preferred in the Treatment of Syphilis?

Thanks to the opportunities provided by medical advances, syphilis is an infection that can largely be treated when managed with appropriate protocols after diagnosis. The main goals of treatment planning are to stop the progression of the infection in the body, prevent damage to critical organs such as the nervous system or cardiovascular system, and eliminate the person’s risk of transmitting the infection to others.

The main medication group most commonly used in syphilis treatment and known for its effectiveness for many years is penicillin derivatives. The stage at which the disease is detected is the most important factor determining the duration of treatment and the method of drug administration.

The general pharmacological options used in treatment are as follows:

• Long-acting penicillin injections administered intramuscularly
• High-dose penicillin treatments administered intravenously
• Alternative antibiotic tablets taken orally

If the disease is detected in the primary, secondary, or early latent stage, meaning at a stage when its spread in the body is limited, penicillin treatment administered as a single intramuscular injection is generally preferred. However, if many years have passed since the infection began or the time of onset is unknown, the treatment protocol is extended. In such cases, multiple injections are planned once a week over consecutive weeks. In more complex situations where the disease affects the nervous system, hospitalization and intensive intravenous treatment may be required.

A different roadmap is followed for patients with a documented and severe allergy to penicillin. These individuals are prescribed alternative oral antibiotic tablets that they must use regularly for a specified number of weeks. The situation is much more sensitive in women diagnosed with syphilis during pregnancy. Because penicillin remains the safest option for protecting the unborn baby, attempts are made to administer this treatment through desensitization procedures under special hospital conditions even if the patient has an allergy. The most critical point in the success of treatment is patient compliance. Especially in weekly injection or long-term tablet treatments, skipping doses or extending the intervals disrupts the treatment process and usually requires the entire protocol to be restarted from the beginning.

Patients are not left on their own after treatment. Within a few hours after the first dose, a strong immune reaction against the bacteria may occur, including fever, headache, muscle pain, and increased redness in the lesions. After this temporary condition is managed, the patient’s recovery process is monitored for months with regular blood tests. A consistent decrease in antibody levels is the most concrete indicator that the treatment has produced a positive result.

What Process Should the Partners of Syphilis Patients Follow?

In the clinical management of sexually transmitted infections, treating only the person who applies to a healthcare facility is not sufficient to break the chain of transmission. To protect public health and prevent repeated cycles of transmission, including the patient’s sexual partners in the process, informing them, and ensuring that they receive the necessary medical support are indispensable parts of the urological approach.

The risk status of partners varies according to the stage of the disease. Recent contacts of a person diagnosed with early-stage syphilis are considered potentially at risk. Even if these individuals’ blood tests are negative at that moment, preventive treatment may be planned by taking into account the possibility that the disease is still in the incubation period. In more prolonged and advanced cases, the period of risky contact extends farther back in time, and partner screening is recommended to cover a broader retrospective period.

In some other urogenital infections, practical applications such as prescribing medication for the patient’s partner may be used when the partner is reluctant to come to the clinic. However, when the issue is syphilis or when there is a possibility that patients simultaneously carry different immune system diseases, this method is generally not recommended. Each individual must be evaluated in a clinical setting according to their own health status, medical history, and physical examination findings to prevent possible complications.

One of the most fundamental rules of this process is the isolation measures the patient must follow until treatment is completed. Physicians strongly emphasize that individuals should avoid all forms of sexual contact, including contact with condom use, until the medication protocol is completed, improvement in blood values is confirmed by the physician, and all skin lesions have disappeared. This both protects the patient’s own recovery process and prevents their partners from being placed at risk.

What Should Be Done to Reduce the Risk of Syphilis Transmission?

No matter how far medical technology advances, the strongest step in fighting infectious diseases is always taking preventive measures before becoming ill. Although syphilis is a disease that can largely be treated with advanced antibiotics, preventing it from entering the body is the most reasonable and healthy decision. When a small redness, painless sore, or unusual condition is noticed in the genital area, a specialist should be consulted without delay instead of acting on unverified information found online.

The points that should be considered in daily life to minimize the risk of infection are as follows:

• Developing the habit of regular and correct condom use
• Taking care to keep the number of sexual partners limited
• Undergoing mutual health screenings before new relationships
• Paying attention to genital hygiene routines
• Consulting a physician without delay after suspicious contact

Short-term antibiotics or creams used without proper knowledge do not eliminate the disease and may only mask the symptoms, making it more difficult for the physician to establish the correct diagnosis. Due to its silent nature, syphilis tends to remain hidden, but regular health checkups and accurate laboratory screenings performed when there is suspicion break this silence. The foundation of a healthy sexual life is that individuals know their own bodies, communicate honestly with their partners, and regularly benefit from preventive healthcare services.

Frequently Asked Questions

Prof. Dr. Berkan Reşorlu

Prof. Dr. Berkan Reşorlu, born in Ankara in 1979, completed his medical education at Ankara University between 1997 and 2003, and his specialization in urology at Ankara University Faculty of Medicine between 2003 and 2008. Academically, he received the title of associate professor in 2013 and professor in 2022.

He has conducted extensive case series studies in the field of endoscopic stone surgery, contributed surgeries performed on children under the age of 1 to the literature, and has gained international recognition with his stone scoring system and experimental surgical models.