Congenital Syphilis

Question 1

When are fetuses typically infected?

Answer 1

In utero after 4th month GA

Infection can occur as early as 9 weeks GA

Question 2

What testing do moms get?

Answer 2

Prenatal testing at the first visit and treatment if reactive
Rescreening at 28-32 weeks and at delivery for high risk women

Question 3

What do you do if mom did not have testing?

Answer 3

Test mom and ensure follow up

Question 4

What is the risk of transmission of syphilis:

• with maternal primary disease
• with maternal secondary disease
• early and late latent

Answer 4

• Untreated primary or secondary: 70-100%
• untreated early latent: 40%
• untreated late latent: 10%

Question 5

What are the types of testing for syphilis?

Answer 5

• 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.

Question 6

What are the two screening approaches used in Canada?

Answer 6

1. Initial screen - RPR. Confirm with treponemal test
2. 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.

Question 7

What is the limitation of treponemal tests?

Answer 7

It remains positive for life unless treatment is initiated early in the disease course

Question 8

How do you monitor for treatment response?

How is this different with primary, secondary and latent disease?

Answer 8

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.

Question 9

Which infants are considered at risk for congenital syphilis?

Answer 9

Maternal RPR titres that do not decline properly
No follow up titres obtained
If re infection is a possibility

Question 10

What is early congenital syphilis and how does it present?

Answer 10

Early = within the first two years of life
Presents = asymptomatic

Question 11

What are clinical features of congenital syphilis

Answer 11

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

Question 12

If mom had syphilis before pregnancy what do you do?

Answer 12

Nothing. Baby is safe.

Question 13

If mom had appropriately treated primary, secondary and latent syphilis, what do you do?

Answer 13

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

Question 14

What do you do if mom had untreated syphilis?

Answer 14

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

Question 15

What do you do if mom was treated within four weeks of delivery or treatment was suboptimal (not penicillin or no RPR decline)?

Answer 15

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

Question 16

Can RPR titres be elevated in a neonate without congenital syphilis?

Answer 16

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

Question 17

What is the treatment of congenital syphilis?

Answer 17

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

Question 18

Can you do one dose of penicillin like they do in adults?

Answer 18

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.

Question 19

When do you retreat?

Answer 19

If there is not a drop of RPR by fourfold

Question 20

Do you need to do anything special for neurosyphilis?

Answer 20

Repeat LP Q6months +/- retreat