Congenital Syphilis

Diagnosis of congenital syphilis is problematic since more than half of all infants are asymptomatic and signs in symptomatic infants may be subtle and nonspecific. Untreated congenital syphilis can cause blindness, deafness and neurological developmental abnormalities. All mothers should have RPR test done (rapid/lab) before baby can be considered for discharge. 

Symptoms and signs of congenital syphilis to check for (xray and bloods optional): 

• Hepatomegaly (usually associated abnormal LFT’s) ± splenomegaly 
• Rash (maculopapular including palms and soles) – can be bullous 
• Snuffles (rhinitis) 
• Generalised lymphadenopathy or oedema 
• Pseudoparalysis (not moving limb due to pain) 
• Large, oedematous, pale placenta 
• Xray long bones: periostitis/osteitis 
• Anaemia, trombocytopoenia and leukocytosis 
• LP not recommended in our setting 

If any syphilis test was positive and baby symptomatic, admit and treat with Pen G 50 000IU/kg IVI 12 hrly for 10 days (uninterrupted – restart course if interrupted >24hrs). An alternative to IVI Pen G treatment is procaine Pen G 50 000 IU/kg IMI dly for 10 days. Make sure blood from baby (not cord blood) was sent for RPR titre. Do FBC, diff, LFT and U+E. Consider x-ray if a limb is clinically affected to screen for pathological fractures. Notify as case of congenital syphilis as soon as diagnosis is confirmed. Book for audiology screen and consider ophthalmology referral if eye involvement suspected. Make arrangements for physical exam and RPR to be repeated 3 monthly until titre negative or decreased 4-fold at local clinic or general POPD. If titre increases or remains reactive at 6 months, consider for admission for re-treatment. Pen G 50 000IU/kg IVI 6hrly for 10 days. (Some late manifestations such as interstitial keratitis are not prevented by treatment ie carefully check children at F/U for congenital syphilis.) Remember all mucocutaneous lesions and their secretions are highly contagious. Use gloves where possible. 

If any syphilis test was positive and baby asymptomatic, give single dose bicillin 50 000 IU IMI stat (max 150 000u). Exception: if mother is fully treated (bicillin – not erythromycin/other A/B ≥ 3 doses received > 1month before delivery) and F/U can be guaranteed. In asymptomatic babies, RPR titres are not needed. In the exceptional event that they are available, only a titre in baby 4-fold the titre in mom (eg 1:8 and 1:32) should be considered for 10 day treatment. Discuss with consultant if uncertain. 

Note: False positive maternal tests (usually ≤1:16) can occur with many diseases and pregnancy itself. If FTA-abs test is negative, the mother does not have syphilis. False negative results can occur when the titre is extremely high (prozone effect) ie consider discussion with laboratory if clinical suspicion of syphilis very high and RPR titre is negative.