Overview
Definition:
Congenital syphilis is a multisystemic infection caused by the spirochete Treponema pallidum, transmitted from an infected pregnant person to the fetus via the placenta
It can lead to severe morbidity and mortality if untreated.
Epidemiology:
Following decades of decline, congenital syphilis has seen a resurgence in many parts of the world, including India, linked to increased rates of maternal syphilis and inadequate prenatal screening and treatment
High-risk populations include those with limited access to healthcare, substance abuse, and multiple sexual partners.
Clinical Significance:
Congenital syphilis is a preventable cause of stillbirth, neonatal death, and long-term disability
Early diagnosis and treatment are crucial to prevent irreversible damage, including neurological impairment, vision loss, and skeletal abnormalities
This topic is vital for pediatricians managing neonates and infants, and for exam preparation.
Clinical Presentation
Early Congenital Syphilis:
Can be asymptomatic at birth or manifest within the first few weeks of life
Common findings include: Nasal discharge (snuffles)
Rash (maculopapular, often involving palms and soles, bullous lesions can occur)
Hepatosplenomegaly
Jaundice
Lymphadenopathy
Osteochondritis (pseudoparalysis of limbs)
Pneumonia alba (rare, severe form).
Late Congenital Syphilis:
Typically appears after 2 years of age, often due to inadequately treated or untreated early congenital syphilis
Manifestations include: Hutchinson's teeth (notched incisors)
Mulberry molars
Interstitial keratitis (leading to vision loss)
Sensorineural hearing loss (eighth nerve deafness)
Saddle nose deformity
Higoumenakis sign (enlarged lateral end of clavicle)
Frontal bossing
Rhagades (perioral and perineal fissures)..
Diagnostic Criteria:
Diagnosis is primarily based on a combination of maternal serological status, infant clinical findings, and infant serological tests
Definitive diagnosis requires positive darkfield microscopy or PCR of lesions or body fluids, or positive serological tests in the infant without maternal treatment
Two standardized approaches exist: one based on risk assessment for infants born to mothers with untreated or inadequately treated syphilis, and another based on specific serological criteria for infants born to mothers with treated syphilis.
Diagnostic Approach
History Taking:
Crucial history includes maternal history of syphilis or STIs, inadequate or absent prenatal care, lack of treatment for syphilis during pregnancy, partner's STI status, and any signs or symptoms in the mother that suggest syphilis
For the infant, inquire about birth weight, gestational age, and any symptoms observed since birth.
Physical Examination:
A thorough, systematic physical examination is paramount
Assess for: Skin lesions (type, distribution, characteristic features)
Mucous membranes (rhagades, snuffles)
Eyes (conjunctivitis, keratitis)
Ears (hearing assessment)
Bones (tenderness, pseudoparalysis)
Abdomen (hepatosplenomegaly)
Genitalia
Neurological assessment.
Investigations:
Infant investigations include: Quantitative VDRL or RPR: Must be performed on infant serum and cerebrospinal fluid (CSF)
A four-fold or greater decline in titer is expected with effective treatment
Treponema pallidum particle agglutination (TPPA) or fluorescent treponemal antibody absorption (FTA-ABS): Confirmatory tests, but do not reliably indicate active infection in infants
CSF examination: Cell count, protein, VDRL
Chest X-ray: May show osteochondritis or pneumonia
Skeletal survey: If specific bone abnormalities are suspected
PCR for Treponema pallidum: May be useful for direct detection in lesions or body fluids.
Differential Diagnosis:
Many conditions can mimic congenital syphilis
Early presentations may include other neonatal infections (e.g., sepsis, viral exanthems, TORCH infections)
Late manifestations can be confused with other causes of hearing loss, vision impairment, bone abnormalities, or dental anomalies
Conditions like congenital rubella syndrome, cytomegalovirus infection, neonatal herpes, and various genetic syndromes should be considered.
Management
Initial Management:
Immediate management is dictated by the infant's risk status and any clinical or laboratory evidence of infection
Infants born to mothers with untreated, inadequately treated, or inadequately documented syphilis treatment require thorough evaluation and often presumptive treatment
All infants diagnosed with congenital syphilis require hospitalization for treatment and monitoring.
Medical Management:
Penicillin is the treatment of choice
Aqueous crystalline penicillin G (IV) is the preferred regimen for neurosyphilis and for symptomatic early or late congenital syphilis
Procaine penicillin G (IM) is an alternative for asymptomatic early congenital syphilis without evidence of CNS involvement
Dosage and duration depend on the stage of the disease and presence of neurosyphilis
For neurosyphilis, treatment is typically 10-14 days of IV aqueous crystalline penicillin G
For non-neurosyphilitic congenital syphilis, treatment is typically 10 days of IV aqueous crystalline penicillin G or 10 days of IM procaine penicillin G
In some cases, a single dose of IM benzathine penicillin G may be considered for asymptomatic infants with no evidence of CNS involvement, but this is debated
Alternatives to penicillin (e.g., azithromycin) are used only in cases of severe penicillin allergy, with careful desensitization protocols required.
Supportive Care:
Supportive care is essential and includes monitoring vital signs, managing feeding difficulties, addressing respiratory distress, and providing appropriate skin care
Close follow-up is critical to assess treatment response and monitor for long-term sequelae.
Follow Up:
Follow-up is intensive
Infants require clinical examinations and serological testing (VDRL/RPR) at 1, 2, 3, 6, and 12 months of age
A four-fold or greater decrease in the titer is expected within 3-6 months
Failure to decline or a sustained rise in titer indicates treatment failure or reinfection and requires re-treatment
Audiological and ophthalmological evaluations are essential, especially in late congenital syphilis.
Complications
Early Complications:
Immediate complications can include failure to thrive, severe anemia, thrombocytopenia, hydrocephalus, meningitis, seizures, pneumonia, myocarditis, hepatitis, and renal abnormalities.
Late Complications:
Long-term sequelae are often irreversible and include neurosyphilis (leading to cognitive impairment, developmental delay), sensorineural hearing loss, interstitial keratitis (uveitis, blindness), Hutchinson's triad (dental abnormalities, eye and ear involvement), saddle nose deformity, and chronic arthritis.
Prevention Strategies:
The most effective prevention is preventing maternal syphilis infection through safe sexual practices and universal screening for syphilis in all pregnant individuals at the first prenatal visit and again in the third trimester if high-risk
Prompt and adequate treatment of maternal syphilis is crucial
Ensuring all pregnant individuals receive adequate prenatal care and are tested for syphilis is paramount
Partner notification and treatment are also key components of prevention.
Key Points
Exam Focus:
Remember that congenital syphilis is a preventable cause of infant mortality and morbidity
DNB/NEET SS questions often focus on diagnostic criteria, differentiating early vs
late manifestations, and the primary treatment of choice (penicillin), including dosage for neurosyphilis
Understand the follow-up serological monitoring requirements.
Clinical Pearls:
Always consider syphilis in any neonate presenting with unexplained rash, hepatosplenomegaly, or bony abnormalities, especially if the mother has a history of inadequate prenatal care
Quantitative maternal and infant serology is key for monitoring treatment response
Do not assume a negative maternal serology in the third trimester rules out congenital syphilis if treatment was inadequate or absent.
Common Mistakes:
Common errors include: Inadequate evaluation of infants born to mothers with inadequately treated syphilis
Failure to perform lumbar puncture for CSF VDRL in infants with signs of neurosyphilis or unexplained neurological symptoms
Incorrect interpretation of infant serology (e.g., relying on non-treponemal tests alone without considering maternal titers and timing)
Underestimating the importance of long-term follow-up for serological and clinical assessment.