Exams and Tests
The first steps in diagnosing
syphilis are discussing the
history of your symptoms and sexual activities with a
health professional and having a
physical exam.
The diagnosis of syphilis is usually confirmed with one of several
blood tests. This is especially true if no sores are
present. If sores are present, a health professional may examine the fluid from
one of the sores with a microscope to see whether syphilis bacteria are present
(dark-field examination).
- A careful examination of the skin and mouth is
performed to look for any rash or other abnormalities.
- For women, a
pelvic exam is done to look for signs of syphilis.
During the pelvic exam, your health professional will look for abnormal sores
in the vagina or on the vulva, labia, rectal area, and inner thighs; these
sores occur during the primary stage of syphilis.
- For pregnant
women, the U.S. Centers for Disease Control and Prevention (CDC) and the
U.S. Preventive Services Task Force (USPSTF) strongly
recommend screening for syphilis because of the severe consequences of being
pregnant while infected or having a child born with the disease (congenital syphilis). Screening should be
done:1
- At the first prenatal visit for all
pregnant women.
- During the third trimester and again at delivery
for pregnant women who have an increased risk of acquiring syphilis.
- For men, a
genital exam is done to look for signs of
syphilis.
- For newborns, the initial evaluation for congenital
syphilis begins with a review of the mother's health and testing the mother for
syphilis. The health professional will examine both mother and newborn for
symptoms.
In the diagnosis of the
primary and secondary stages of syphilis,
lumbar puncture (spinal tap) is needed in rare cases.
A lumbar puncture may be done in adults:
- If there is evidence of
tertiary syphilis (such as
aortic aneurysm,
gumma, or
iritis) or if
neurosyphilis is suspected.
- If penicillin
or another recommended antibiotic cannot be used for treatment in latent
syphilis. If the appropriate antibiotic cannot be used, it is important to
determine whether fluid from the spinal column and brain (cerebrospinal fluid) is infected because specific
treatment methods are needed to effectively treat infected cerebrospinal
fluid.
- Infected with
HIV. Some experts recommend lumbar puncture in all
HIV-infected people with syphilis.
- To check whether a person is
cured of neurosyphilis.
In newborns and children, a lumbar puncture may be done if:
- There are signs of congenital
syphilis.
- The child's mother had syphilis and she was not treated,
was not treated adequately, or was treated after the 20th week of
pregnancy.
- The child's mother was treated with an
antibiotic other than penicillin.
Additional testing should be done to determine whether other
sexually transmitted infections are present, especially:
The diagnosis of syphilis can be delayed or complicated because its
symptoms are very similar to those of many
other diseases and are sometimes not recognized.
Syphilis has historically been referred to as "the great imitator."
Early Detection
Screening for syphilis is strongly recommended for pregnant women
and for people who are at increased risk for the disease.
People at high risk of contracting syphilis include those
who:2
- Have unprotected sex (do not use condoms or
do not use them correctly). This risk is especially high among men who have sex
with men.
- Have multiple sex partners, particularly if they live in
an area of the country where syphilis is more common.
- Have a sex
partner who has syphilis.
- Have sex with a partner who has multiple
sex partners.
- Exchange money or drugs for sex
(prostitution).
- Have human immunodeficiency virus (HIV) infection.
The CDC and the
U.S. Preventive Services Task Force (USPSTF) strongly
recommend that pregnant women be screened for syphilis because of the severe
consequences of being pregnant while infected or having a child born with
congenital syphilis. Screening should be done:1
- At the first prenatal visit for all pregnant
women.
- During the third trimester and again at delivery for
pregnant women who have an increased risk of acquiring syphilis.