I was wondering if I have syphilis. I am afraid to go to the doctor because if he says I have it then I will be in big trouble. I tried to talk with my mother, but she doesn't think I have ever had any sexual contact. I have a rash all over my stomach, breasts, upper genitalia, and on the top of my bottom. It doesn't itch or anything; it's just there. I got it five days after I had sexual intercourse with my boyfriend. What could this be? I am really confused and worried.

T.E.

It is impossible for me to say what you have without a personal examination and testing. What I can do is give you some information about syphilis and make some assumptions about your situation. Regardless of what I tell you, you should see a physician to find out conclusively what you have. If you are over 18, then the physician is obligated not to tell your parents. If you are under 18, most physicians would still not tell your parents, but if privacy is a concern, you should call the doctor's office and ask about the doctor's policy on confidentiality for patients under 18, before you see the doctor.

Syphilis is a common sexually transmitted disease, caused by the bacterium Treponema pallidum. There are three main stages of syphilis: primary, secondary and tertiary. The first stage, primary syphilis, consists of a chancre -- a small ulcer (break in the skin or mucous membrane) at the site of initial infection -- that usually appears from three to 21 days after exposure. Diagnosing primary syphilis involves examining material from the chancre under the microscope. In men, the chancre is usually on the penis, while in women, it can be on the external genitalia, the cervix (the entrance to the uterus) or the anus. The ulcer has raised edges and is usually painless. In some people, especially in women, the chancre may not be apparent. Based on your symptoms, you clearly do not have primary syphilis. The third or late stage of syphilis, tertiary syphilis, is also not a possibility in your case, because it occurs years after infection in untreated people. Tertiary syphilis can attack the nervous system, causing weakness and mental problems, and can also lead to serious heart abnormalities.

Although your symptoms could be due to other causes, secondary syphilis is consistent with your description. This occurs two to eight weeks after the development of the chancre. The most striking manifestation of secondary syphilis is a rash. This rash can be highly variable, but it commonly involves many flat and raised lesions -- sometimes red in color -- that are spread throughout the body, especially on the palms and soles. In fact, there are not many rashes that involve the palms and soles, and syphilis is the most common. Since secondary syphilis occurs two weeks or more after exposure, if the sexual experience you recently had with your boyfriend was your first, it is unlikely that you have this infection. If you have had sex with him multiple times, however, then secondary syphilis is a possibility. A simple blood test can confirm or rule out the possibility of this infection, which is treated with a course of antibiotics.

Another possibility is that you have another sexually transmitted infection, namely herpes. While herpes infection itself causes blisters that burst to form ulcers, sometimes a rash called erythema multiforme can develop at around the same time. This rash is scattered throughout the body, although the palms, soles, and the sides of the hands are common locations. This is probably the second most common rash to involve the palms and soles. If this were the case, I would expect you to also have findings typical of herpes (such as blisters), but they are not always present. On the other hand, perhaps your illness is not sexually transmitted at all. Your rash could be caused by a variety of infections, such as enterovirus, adenovirus or rubella (the virus that causes German measles) -- or it could be an allergic reaction to a medication or other substance. Without getting more information, it is impossible to tell you for certain. You should see a doctor to find out what is causing your rash and, if necessary, obtain treatment.