INFECTIOUS DISEASE—1
Late latent syphilis: associated with host resistance to
[15]
reinfection and to infectious relapse. However, a
SYPHILIS pregnant woman with late latent syphilis can infect
Caused by spirochete, Treponema pallidum. Infection her fetus in utero, and an infection can be
occurs primarily as a result of sexual contact. The transmitted via transfused contaminated blood.
organism penetrates mucosal barriers and is highly
contagious. Tertiary Syphilis
Infection develops in 10 percent of contacts after a Approximately one-third of patients with untreated
single exposure and in 70 percent after multiple secondary disease ultimately develop tertiary
exposures. syphilis after an interval of several years.
May be transmitted perinatally. Clinical Manifestations:
Prevalence: dramatically in recent yrs, coincident w/ gumma formation
in cases of HIV infection and the growing cardiac lesions: aortic insufficiency and dissecting aortic
epidemic of drug abuse. Greatest in 15 to 24 yrs, aneurysm
and blacks and Hispanics living in urban areas. CNS (neurosyphilis): meningovascular syphilis, cranial
nerve palsies, generalized paresis, tabes dorsalis,
Clinical Manifestations and optic atrophy, uveitis, and Argyll-Robertson pupils.
Four to 9 percent of patients with untreated syphilis
Staging ultimately develop neurosyphilis.
Primary Syphilis Diagnosis
Incubation period ranges from 10 to 90 days. T. pallidum cannot be cultured.
At the end of this period, the characteristic raised, Darkfield microscopy and fluorescent antibody staining
painless chancre appears. can be used to evaluate early lesions.
In women, the chancre is usually on the cervix or Serology: infection in the latent stage is diagnosed by
vaginal wall and may not be apparent except on serology. ~ 100 % of patients will have + serologic
close inspection. In some patients, the chancre may test within 4 weeks of their primary infection.
be present in extragenital sites such as the fingers, VDRL and RPR: Initial screening test. Several
oropharynx, nipples, or anus. The chancre usually factors can cause false-positive test results such
heals in 3 to 6 weeks even without specific as collagen vascular dz, bacterial and viral
antimicrobial treatment. infections, multiple myeloma, advanced cancer,
chronic liver disease, IVDU, multiple blood
Secondary Syphilis transfusions, and pregnancy.
Results from multiplication and dissemination of the FTA-ABS and MHA-TP: Positive screening test
spirochete. Lasts until a sufficient host response must be confirmed by a specific treponemal assay
develops to exert some immune control over the (fluorescent treponemal antibody absorption test
spirochete. (FTA-ABS) or microhemagglutination assay
Begins 2 to 8 weeks (according to another paper 2 to 6 (MHA-TP)). False-positive treponemal tests have
months after their primary infection) after the been reported in patients with Lyme disease,
appearance of a chancre, but this period is quite leprosy, malaria, mononucleosis, and collagen
variable. The primary chancre may still be present. vascular disease.
Lumbar puncture: indicated when neurosyphilis is
Clinical manifestations: suspected and in all patients who are coinfected
1) generalized maculopapular rash on the palms of the with syphilis and HIV.
hands and soles of the feet. May be confused with mononuclear pleocytosis (10 to 400 cells/mm3 )
disseminated gonococcal infection, measles, elevated protein (>45 mg/dl)
rubella, scabies, psoriasis, and drug eruption.
positive VDRL test.
2) mucous patches of the oropharynx
Quantitative Tests: With appropriate antibiotic
3) condylomata lata: gray, raised papules that appear
treatment, quantitative nontreponemal tests usually
on the vulva and near the anus. Papules enlarge,
decrease fourfold within 3 months in patients with
coalesce, and erode to produce painless, broad,
primary or secondary syphilis. When this decline
moist, gray-white to erythematous, highly infectious
does not occur, patients should be re-evaluated and
plaques.
considered for a second course of treatment.
4) bone tenderness
Antibody titers may decline more slowly in patients with
5) iritis
more advanced stages of disease.
6) alopecia
Specific treponemal tests typically remain positive for
7) generalized lymphadenopathy.
life even after adequate treatment, although ~25
Even without treatment, the signs of primary and
percent of patients may ultimately become
secondary syphilis resolve after 1 to 3 months, and
seronegative. Patients should be followed with
the patient enters a stage of latent infection, in
quantitative titers for up to 12 to 18 months after
which specific antibody tests are positive, but there
their initial infection to determine if200 they
are no symptoms.
become seronegative.
Latent Syphilis Perinatal Complications
Untreated patients then enter a latent phase of their Syphilis in pregnancy may be associated with an
illness. In this phase, infected women pose only a increased risk of fetal demise, intrauterine growth
small risk of horizontal transmission of infection to restriction, and preterm delivery. It also may
their sexual partner. However, vertical transmission accelerate the course of HIV infection in pregnant
to the fetus still can occur. women.
FTA-abs, or MHATP, or ELISA is positive but during Congenital infection. T. pallidum can cross the placenta
which there are no clinical manifestations, normal and infect the fetus at any stage of gestation. Up to
CSF, and a normal CXR. one-third of fetuses with congenital syphilis are
Early latent syphilis: first 4 years during which a stillborn. The frequency of vertical transmission
relapse may occur and the patient is "infectious." varies primarily with the stage of maternal disease.
90% of relapses occur in the first year, and each T. pallidum has been recovered from fetal blood and
recurring episode is less florid. Mucocutaneous amniotic fluid in cases of congenital infection.
relapses are the most common. Condylomata lata,
however, are common. Frequency of Vertical Transmission of Syphilis:
Primary 50% Secondary 50%
Early Latent 40% Late Latent 10%
2—INFECTIOUS DISEASE
Tertiary 10%
Prenatal diagnosis: Ultrasound has greatest potential for
identifying the severely infected fetus. Signs are
placentomegaly, intrauterine growth restriction,
microcephaly, hepatosplenomegaly, and hydrops.
Treatment
Penicillin is the drug of choice due to proven ability to
prevent congenital infection in most cases.
Patients who have a previous history of an allergic
reaction to penicillin should be skin tested to
determine if their allergy persists. If allergy is
confirmed, patients should be desensitized with
either oral or intravenous regimens. Desensitization
can usually be completed within 4 hours.
Pregnant women receiving penicillin for treatment of
syphilis may develop uterine contractions and
decreased fetal movement as a result of a Jarisch-
Herxheimer reaction. This reaction happens in 45%
of women. The reaction was particularly likely in
those patients who had primary and secondary
syphilis, and the abnormalities typically appeared 2
to 8 hours after treatment and resolved within 24
hours. No reliable clinical or laboratory assessments
that predict which patients will develop the Jarisch-
Herxheimer reaction, and no specific treatment is
available.
Primary, secondary, or latent syphilis 1 year's duration or cardiovascular
syphilis:
Benzathine penicillin G, 2.4 million units IM
weekly × 3
Erythromycin, 500 mg QID × 30 days
Neurosyphilis: Aqueous crystalline penicillin G, 2-4
million units Q4h × 10-14 days, followed by
benzathine penicillin G, 2.4 million units IM × 1