Congenital Syphilis Flashcards
When are fetuses typically infected?
In utero after 4th month GA
Infection can occur as early as 9 weeks GA
What testing do moms get?
Prenatal testing at the first visit and treatment if reactive
Rescreening at 28-32 weeks and at delivery for high risk women
What do you do if mom did not have testing?
Test mom and ensure follow up
What is the risk of transmission of syphilis:
- with maternal primary disease
- with maternal secondary disease
- early and late latent
- Untreated primary or secondary: 70-100%
- untreated early latent: 40%
- untreated late latent: 10%
What are the types of testing for syphilis?
- nontreponemal test: CSF VDRL and RPR
- treponemal test: FTA-ABS (fluorescent treponemal antibody absorption), treponema pallidum particle agglutination, microhemagglutination for T pallidum, EIA (enzyme immunoassay) and line blot immunoassay.
What are the two screening approaches used in Canada?
- Initial screen - RPR. Confirm with treponemal test
- Initial screen - EIA. Confirm with another treponemal test
EIA has heigher sensitivity and specificity than RPR
NB you stil need to do RPR titres because the titres is used for staging.
What is the limitation of treponemal tests?
It remains positive for life unless treatment is initiated early in the disease course
How do you monitor for treatment response?
How is this different with primary, secondary and latent disease?
With the RPR titres
PRIMARY disease: with appropriate treatment, you expect a 4-fold drop in RPR titres at six months, 8-fold at 12 months and 16-fold at 24 months.
SECONDARY ds: with appropriate treatment, you expect an 8-fold drop in RPR titres at six months and 16-fold at 12 months
LATENT ds: 4-fold drop at 12 months.
Which infants are considered at risk for congenital syphilis?
Maternal RPR titres that do not decline properly
No follow up titres obtained
If re infection is a possibility
What is early congenital syphilis and how does it present?
Early = within the first two years of life Presents = asymptomatic
What are clinical features of congenital syphilis
Spontaneous abortion Necrotising fasciitis - of umbilical stump Rhinitis/snuffles Rash - diffuse maculopapular +/- desquamation HSM Lymphadenopathy Neurosyphilis Anemia and thrombocytopenia Interstitial keratitis Hutchinsons teeth Mulberry molars VIII palsy MSK STUFF - osteochondritis and perichondritis, frontal bossing, small maxilla, saddle nose
If mom had syphilis before pregnancy what do you do?
Nothing. Baby is safe.
If mom had appropriately treated primary, secondary and latent syphilis, what do you do?
Primary, secondary and early latent: Test baby RPR and TT at 0, 3, 6 and 18 months.
Late latent: test baby at 0, 6 and 18 months
What do you do if mom had untreated syphilis?
Assess at birth, do RPR/TT at 0, 3, 6 and 18 months. And get CSF and X-rays
Treat at birth for congenital syphilis
What do you do if mom was treated within four weeks of delivery or treatment was suboptimal (not penicillin or no RPR decline)?
Assess at birth, do RPR/TT at 0, 3, 6 and 18 months. And get CSF and X-RAYS
Treat at birth for congenital syphilis
Can RPR titres be elevated in a neonate without congenital syphilis?
Yes, because the RPR can cross the placenta. So they decline by 3 months and are usually negative by 6 months.
The course of EIA is less clear but are usually negative by 12 months and certainly by 18 months
What is the treatment of congenital syphilis?
10 days of benzanthine penicillin G 50000 units/kg
Q12H if less than 1 week of age
Q8H for 1-4 weeks
Q6H if older than 4 weeks
Can you do one dose of penicillin like they do in adults?
Some experts suggest this or qweekly, but there is no evidence for this. So this approach should be discouraged unless no likelihood of follow up.
When do you retreat?
If there is not a drop of RPR by fourfold
Do you need to do anything special for neurosyphilis?
Repeat LP Q6months +/- retreat
