In June 2023, we commenced a project to review and update the Maternity and Neonatal eHandbook guidelines with a view to completion in 2024. Please be aware that pending this review, some of the current guidelines may be out of date. In the meantime, we recommend that you also refer to more contemporaneous evidence.
Congenital syphilis is rare in Australia, with disadvantaged groups at higher risk of infection.
Congenital infection with syphilis can occur during pregnancy or the peripartum period.
Screening at the initial antenatal visit is part of routine obstetric care since women may have asymptomatic latent disease.
Transplacental infection can occur at any stage of pregnancy and during any stage of maternal disease.
Untreated maternal syphilis can result in:
- stillbirth/perinatal death
- premature delivery
- long-term neurological sequelae for half of the survivors
- bone deformities
Transmission rates for primary chancre is high and for secondary illness moderate. In established latent syphilis, risk of vertical transmission is low.
Treponema pallidum infection remains treatable with penicillin.
The infected baby can be asymptomatic at birth or have disseminated sepsis.
Possible presenting features
Reticulo-endothelial/haemotogical features include:
- generalised lymphadenopathy and hepatosplenomegaly seen in over 50 per cent of cases
- haemolytic anaemia/thrombocytopenia/pancytopenia can occur
- occasional leucocytosis
- jaundice (unconjugated/conjugated or mixed) is common.
Mucosal features include:
- rhinitis (snuffles) develops at one week and worsens (initially clear then progressively purulent and blood-stained)
- mucous 'patches' seen on palate and lips
- perioral and perianal condylomata
- ulceration of nasal mucosa can lead to 'saddle-nose deformity' in longer term.
Cutaneous features include:
- maculo-papular eruption over buttocks and lower torso, palms and soles
- bullous eruptions (pemphigus syphiliticus) which mimic staphylococcal infection
Bone involvement may include:
- osteochondritis, periostitis, osteitis is very common (> 75 per cent of cases).
- usually asymptomatic initially but can lead to deformity and pathological fracture.
Neurosyphilis, although rare at birth, may present with:
- eye involvement
Other clinical features
Other clinical features that may present include:
- renal (nephrotic) involvement.
If syphilis is untreated, late features may include:
- Hutchison's teeth and other dental deformity
- sabre tibia
- keratitis and blindness
- nerve deafness
- saddle nose deformity
- frontal skull bossing
- development impairment.
Issues to note about investigations for syphilis:
- Pregnant women are screened with non-specific treponemal tests (RPR and VDRL titre).
- If positive, then a specific TPHA/FTA-Abs titre will be performed.
- Serum IgM in newborn babies with congenital syphilis is positive in around 90 per cent of cases.
- Diagnosis of congenital infection can be confirmed by demonstration of treponema pallidum on dark ground microscopy on specimens from lesions on skin, placenta or other tissues.
- A fourfold rise in the baby’s antibody titre over the first three months is considered diagnostic.
Other tests for syphilis
Other tests include:
- liver function tests
- syphilis serology
- urinalysis for proteinuria
- x-rays of long bones
- lumbar puncture
- CSF abnormalities should be considered suggestive of CNS infection.
- A positive CSF VDRL titre or treponema PCR is diagnostic of CNS involvement.
Ongoing follow-up will be needed and if follow up cannot be assured, the baby should be treated.
Issues to note about management of infants with suspected or confirmed syphilis infection:
- Babies born to mothers who have not been adequately treated should be considered as infected.
- Infants with suspected or confirmed infection should be treated with penicillin for at least 10 days:
- benzyl penicillin, 50 mg/kg per dose 12-hourly, IV for 10 days
- procaine penicillin, 50 mg/kg daily, IM for 10 days.
- Infants with low antibody levels whose mother was treated appropriately and has evidence of falling RPR/VDRL titres, is unlikely to be at risk.
- Ongoing follow-up will be needed and if follow up cannot be assured, the baby should be treated.
Prevention relies upon adequate antenatal services and screening facilities.
Follow-up for neonatal syphilis infection includes:
- Follow up serology at 1, 2, 4, 6, 12 months of age or until non-reactive on 2 occasions.
- In cases of neurosyphilis, repeat CSF examination at 6 months.
- Re-treatment is needed if persistently reactive serology or abnormal CSF.
- Isaacs D, Moxon ER. ‘Handbook of Neonatal Infections - a practical guide’. WB Saunders, London. 1999.
- Remington JS, Klein JO. ‘Infectious Diseases of the Fetus and Newborn Infant’ 5Th Ed. WB Saunders, Philadelphia. 2000.
- Davies EG, Elliman DAC, et al. ‘Manual of Childhood Infections’. WB Saunders, London, 1996.
- Jeffries DG, Hudson CN. ‘Viral infections in Obstetrics and Gynaecology’. Arnold, London, 1999.
- Murph JR. 'Rubella and syphilis: continuing causes of congenital infection in the 1990s.' Seminars in Pediatric Neurology. 1(1):26-35, 1994 Sep.
- Hollier LM. Cox SM. 'Syphilis'. Seminars in Perinatology. 22(4):323-31, 1998 Aug
- Merck Manuals
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First published: May 2014
Review by: May 2017