Syphilis – or skeletal blood – is a sexually transmitted disease caused by the bacterium Treponema pallidum.
The number of syphilis patients reached a peak during World War II, then fell sharply until the 60s, and then began to rise again. During this time many cases of homosexual men were observed. The ratio remained largely stable until the mid-1980s, then as a result of the AIDS epidemic, the practice of safe sex was emphasized, so the incidence of syphilis began to decline gradually. Consequently, the number of syphilis patients also declined.
However, this decline was followed by a rapid increase in the number of new cases among crack cocaine users, mainly affecting women and their newborns. As a result of recent prevention programs, the recurrence of syphilis has decreased again in most of the US.
After the healing process the infected person will not become immune to the disease and can get infected again.
How does it infect?
The bacterium enters the body through the mucosa of the vagina or the mouth, or possibly through the skin. In a few hours it reaches the nearest lymph nodes, and from there it spread through the body via the bloodstream. During pregnancy it infects the fetus in a few hours causing birth defects and other changes.
Symptoms of a syphilis infection usually present themselves in the first 1-13 (usually 3-4) weeks after transmission. There are multiple stages of Treponema pallidum infection: the first, the second, the latent and the tertiary. The infection can last for years, and as a rare complication, it can cause heart disease, brain damage and death.
During the first stage a painless sore (a „chancre”) appears at the site of transmission: on the penis, the vulva (the outer female sex organ) or in the vagina. The sore can appear in the anus or the rectum, on the lips, the tongue and the throat, on the cervix, the fingers and rarely on other parts of the body, too. There is usually only one sore, but in rare cases multiple sores can develop.
The chancre is a small, red, bumpy spot and it progresses into an open sore that is still painless. It does not bleed but scratching can induce the secretion of a highly infective, clear fluid. The nearby lymph nodes are usually enlarged, but these are painless, too. Since these symptoms do not cause many complaints, patients usually ignore these. The half of infected women and the third of infected men are unaware of this sore. It usually disappears in 3-12 weeks and the patients seem to completely recovered.
The second stage typically begins with a rash that develops 6-12 weeks after the transmission. In every fourth patient, the healing sore is still visible. The rash can disappear but it can last for months as well. It often resolves in untreated patients, too, but in a few weeks or months other symptoms can develop.
In the second stage 80% of the patients develop mouth sores, 50% of them have enlarged lymph nodes throughout their body and 10% present suffer from an eye inflammation. The inflammation of the eyes does not usually cause symptoms, however, the optic nerve might swell that can lead to blurred vision. 10% of the patients have severe pain in their bones and joints. The inflammation of the kidneys can cause the presence of excess proteins in the urine, while the inflammation of the liver can cause jaundice. The inflammation of the outer membranes of the brain can cause headache, stiff neck and sometimes hearing loss, too.
Elevated lesions might appear at the skin-mucosa margin (e.g. at the inner border of the labia majora and the vulva) and at moist areas of the skin. These are called condyloma latum, they are highly contagious and in time they flatten, and they turn either grey or a pale shade of pink. Hair falls out in patches leaving behind a moth-eaten appearance. Additional symptoms include malaise, loss of appetite, nausea, fatigue, fever and anemia.
After the patient recovers from the second stage, the disease enters an asymptomatic latent phase. This stage can last for years or decades (in some cases until the patient’s death). In the first part of this stage the contagious ulcers might reappear.
In the third stage of the disease (late syphilis) the patient is not contagious anymore. Symptoms vary from mild to devastatingly severe. There are three groups of symptoms: benign late syphilis, cardiovascular syphilis (affecting the heart and vessels) and neurosyphilis (affecting the nervous system).
Benign late syphilis occurs rarely and presents with the appearance of growths (called „gummas”) on different organs. They grow and heal slowly and leave scars. They can appear anywhere on the body but usually present on the legs below the knee, the upper torso, the face and the scalp. They can affect bones as well which leads to deep, piercing pain that is typically worse at night.
Cardiovascular syphilis develops 10-25 years after the initial infection causing the formation of an aneurysm (the weakening and bulging of the wall) of the aorta (the main vessel originating from the heart) or insufficiency of the aortic valve. These complications can present with chest pain and heart failure and might be lethal.
Neurosyphilis (syphilis of the nervous system) affects cca. 5% of all untreated patients.
The clinical suspicion of syphilis is based on the symptoms and the final diagnosis is confirmed by laboratory results and by findings of the patient’s physical examination.
In the first and second stage syphilis can be diagnosed by the microscopic examination of tissue taken from the ulcers of the skin or the oral mucosa, while detection of certain antibodies in the blood can be used as a screening test. In the third stage diagnosis is based on symptoms and antibody tests.
Since patients in the first and second stages are contagious, they (and their sexual partners) have to avoid any sexual activities before finishing their treatment.
Penicillin, which is the most effective medication in any stage, is usually administered intravenously.
First, second and latent stage patients have an excellent prognosis after being treated, however, the prognosis of the third stage, which affects the brain and the heart, is quite poor as its complications are usually irreversible.