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PubMed This is a summary of 24 peer-reviewed journal articles Updated
Pediatrics

Recognizing the Signs of Congenital Syphilis

At a Glance

Most babies born with congenital syphilis show no symptoms at birth, making medical testing essential. Early signs can include an infectious runny nose called 'snuffles' or painful bone inflammation, but completing early treatment entirely prevents permanent late-stage bone and dental deformities.

Identifying the symptoms of congenital syphilis is challenging because the infection can look very different from one baby to the next. Many babies are born appearing completely healthy, which is why doctors rely on testing rather than just a physical exam [1][2].

If your baby does show signs, they are generally divided into three stages: signs seen before birth, “early” signs (birth to age 2), and “late” signs (after age 2).

Signs Seen Before Birth

During pregnancy, a doctor might see signs of infection on a fetal ultrasound (a specialized imaging test used to see the baby in the womb). These signs do not appear in every case, but when they do, they are important clues [3]. Common findings include:

  • Placentomegaly: An abnormally large or heavy placenta [4][3].
  • Fetal Hydrops: A serious condition where large amounts of fluid build up in the baby’s tissues and organs [5].
  • Hepatomegaly: An enlarged liver in the fetus [3][4].
  • Intrauterine Growth Restriction (IUGR): When the baby is not growing at the expected rate for their age [3].

Early Symptoms (Birth to 2 Years)

Most babies (60-90%) with congenital syphilis appear asymptomatic (showing no symptoms) at birth [1][6]. This happens because the infection may still be in its very early stages or suppressed by the mother’s immune system. However, if left untreated, symptoms usually appear within the first few weeks or months [7].

  • Mucocutaneous Lesions: These are rashes or sores. A common early sign is pemphigus syphiliticus, which involves blisters or peeling skin, especially on the palms of the hands and soles of the feet [8][9].
  • Snuffles: A persistent, heavy nasal discharge (runny nose) that is highly infectious because it contains the bacteria [7].
    • Infection Control Tip: You can safely handle your baby! However, practice strict hygiene: wash your hands frequently with soap and water, wear disposable gloves when wiping the baby’s nose or handling soiled tissues, and safely discard tissues immediately.
  • Hepatosplenomegaly: Swelling or enlargement of the liver and spleen [10][11].
  • Pseudoparalysis of Parrot: A condition where a baby stops moving an arm or leg because their bones are so inflamed and painful that it feels like the limb is paralyzed [12][13].
  • Bone Changes: Inflammation of the bones (osteochondritis) can be seen on X-rays, often appearing as symmetric patterns on both sides of the body [14][15].

Late Symptoms (After 2 Years)

If the infection is not treated early, it can cause permanent physical changes known as stigmata [16][17]. Remember: Completing the 10-day early treatment entirely prevents these late-stage manifestations from occurring.

  • Dental Changes: These include Hutchinson’s incisors (pegged or notched front teeth) and mulberry molars (back teeth with many small bumps instead of a flat surface) [18][19].
  • Skeletal Changes: Such as a “saddle nose” (a collapsed bridge of the nose) or “saber shins” (an outward curving of the shin bones) [17].
  • Hutchinson’s Triad: A rare combination of notched teeth, interstitial keratitis (inflammation of the eye), and sensorineural hearing loss [20][17].

Why It Is Often Misunderstood

Congenital syphilis is a “great mimicker.” Its symptoms—like a fever, low energy, or difficulty breathing—can look exactly like bacterial sepsis (a severe blood infection) or other common newborn illnesses [21][22]. This is why doctors must maintain a “high index of suspicion,” testing for syphilis even when a baby seems to have a different infection [6][23]. Timely testing and treatment are the only ways to prevent these symptoms from progressing [24].

Common questions in this guide

Why didn't my baby have any symptoms of congenital syphilis at birth?
Most babies with congenital syphilis appear completely healthy at birth because the infection may be in its very early stages or temporarily suppressed by the mother's immune system. This is why doctors rely on specific blood tests rather than just a physical exam to diagnose the infection.
What are 'snuffles' in a baby with congenital syphilis?
'Snuffles' is a persistent, heavy runny nose that is a common early sign of congenital syphilis. The nasal discharge is highly infectious, so caregivers must practice strict hygiene, including frequent handwashing and wearing disposable gloves when wiping the baby's nose.
What are the long-term effects if congenital syphilis isn't treated?
If the infection is not treated early, it can cause permanent physical changes known as stigmata. These late-stage symptoms can include dental issues like notched front teeth, bone changes such as a collapsed nasal bridge, and even hearing or vision problems.
How can doctors tell if my unborn baby might have congenital syphilis?
Doctors can sometimes spot signs of the infection on a fetal ultrasound during pregnancy. These clues may include an abnormally large placenta, fluid buildup in the baby's tissues, an enlarged liver, or slower-than-expected growth.
Why is congenital syphilis sometimes mistaken for other newborn illnesses?
Congenital syphilis is known as a 'great mimicker' because its general symptoms, such as fever, low energy, and difficulty breathing, look exactly like bacterial sepsis and other common newborn infections.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Since many babies are asymptomatic at birth, what specific tests are you using to confirm whether my baby is infected?
  2. 2.Does my baby need a skeletal survey (bone X-rays) to check for signs of bone inflammation or fractures?
  3. 3.Are my baby's enlarged liver or spleen (if present) typical for this condition, and how will we monitor them?
  4. 4.What signs should I look for in the next few months that might suggest an early-stage symptom like 'snuffles' or pseudoparalysis?
  5. 5.If my baby tests negative now but was exposed, what is the follow-up schedule to ensure late-stage symptoms don't develop later?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (24)
  1. 1

    Clinical-Demographic and Laboratory Profile of the Mother-Child Binomial With Syphilis in a Tertiary-Level Hospital in Mexico.

    Pérez Cavazos S, Molina de la Garza JF, Rodríguez Saldivar MM, et al.

    Sexually transmitted diseases 2024; (51(1)):11-14 doi:10.1097/OLQ.0000000000001878.

    PMID: 37889942
  2. 2

    How to interpret syphilis testing.

    Ali F, Ye S, Meesters K

    Archives of disease in childhood. Education and practice edition 2026; (111(2)):71-77 doi:10.1136/archdischild-2025-329055.

    PMID: 40962432
  3. 3

    Fetal and neonatal abnormalities due to congenital syphilis: A literature review.

    David M, Hcini N, Mandelbrot L, et al.

    Prenatal diagnosis 2022; (42(5)):643-655 doi:10.1002/pd.6135.

    PMID: 35352829
  4. 4

    Placental weights of neonates born with symptomatic congenital syphilis.

    Pillay S, Horn AR, Tooke L

    Frontiers in pediatrics 2023; (11()):1215387 doi:10.3389/fped.2023.1215387.

    PMID: 37868268
  5. 5

    Non-immune Hydrops Fetalis and Hepatic Dysfunction in a Preterm Infant With Congenital Syphilis.

    Duby J, Bitnun A, Shah V, et al.

    Frontiers in pediatrics 2019; (7()):508 doi:10.3389/fped.2019.00508.

    PMID: 31921721
  6. 6

    The nurse's role in preventing and treating congenital syphilis.

    Mersiovsky A

    Nursing 2026; (56(1)):24-32 doi:10.1097/NSG.0000000000000312.

    PMID: 41437465
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    Congenital Syphilis-An Illustrative Review.

    Sankaran D, Partridge E, Lakshminrusimha S

    Children (Basel, Switzerland) 2023; (10(8)) doi:10.3390/children10081310.

    PMID: 37628309
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    Pemphigus syphiliticus with Jarisch-Herxheimer reaction in a newborn.

    Pañgan EAC, Asetre-Luna I, Uy MEV, Esguerra AKM

    Pediatric dermatology 2024; (41(1)):153-155 doi:10.1111/pde.15428.

    PMID: 37675915
  9. 9

    Congenital Bullous Syphilis: A Case Report from Italy and a Comprehensive Literature Review.

    Cammarata E, Esposto E, Di Cristo N, et al.

    Medicina (Kaunas, Lithuania) 2025; (61(1)) doi:10.3390/medicina61010158.

    PMID: 39859140
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    'Unveiling the hidden threat: Delayed presentation of congenital syphilis'.

    Mishra N, Shukla A, Gupta A

    Tropical doctor 2025; (55(2)):150-151 doi:10.1177/00494755251325318.

    PMID: 40033933
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    An analysis of the clinical features of children with early congenital Syphilis and Syphilitic Hepatitis.

    Yang H, Zhang H, Wang C, Pang L

    BMC pediatrics 2021; (21(1)):498 doi:10.1186/s12887-021-02932-5.

    PMID: 34753447
  12. 12

    Early limb paralysis in infants: do not forget about congenital syphilis.

    Scarcella A, Bortone B, Tersigni C, et al.

    International journal of STD & AIDS 2021; (32(8)):768-770 doi:10.1177/0956462420987442.

    PMID: 33533292
  13. 13

    An unusual presentation of early congenital syphilis with annular configuration of blisters resembling "string-of-pearls".

    Mathews J, Naseem JA, Neupane N, et al.

    Pediatric dermatology 2019; (36(5)):735-736 doi:10.1111/pde.13880.

    PMID: 31177579
  14. 14

    Congenital syphilis as the cause of multiple bone fractures in a young infant case report.

    Koliou M, Chatzicharalampous E, Charalambous M, Aristeidou K

    BMC pediatrics 2022; (22(1)):728 doi:10.1186/s12887-022-03789-y.

    PMID: 36539748
  15. 15

    Clinical and Imaging Features of Syphilis from Head to Toe.

    Kano S, Inoue A, Masuoka S, et al.

    Radiographics : a review publication of the Radiological Society of North America, Inc 2025; (45(6)):e240170 doi:10.1148/rg.240170.

    PMID: 40338795
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    An inscrutable entity: A case report of late congenital syphilis.

    Rathwa PK, Chauhan J, Patel NP, et al.

    Indian journal of sexually transmitted diseases and AIDS 2022; (43(2)):192-193 doi:10.4103/ijstd.ijstd_1_22.

    PMID: 36743077
  17. 17

    Congenital Syphilis: A Threat to Neonatal Health.

    Holland M, Steger A, Jnah A

    Neonatal network : NN 2025; (44(6)):376-388 doi:10.1891/NN-2025-0020.

    PMID: 41371975
  18. 18

    Dental Stigmata of Congenital Syphilis: A Historic Review With Present Day Relevance.

    Nissanka-Jayasuriya EH, Odell EW, Phillips C

    Head and neck pathology 2016; (10(3)):327-31 doi:10.1007/s12105-016-0703-z.

    PMID: 26897633
  19. 19

    A unique case report of mulberry second molar in a non-syphilitic patient.

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    Medicine 2024; (103(30)):e39127 doi:10.1097/MD.0000000000039127.

    PMID: 39058872
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    Syphilis.

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  21. 21

    Congenital neurosyphilis presenting as neonatal sepsis.

    Iskandar W, Permatagalih V, Primadi A, Gamayani U

    Journal of infection in developing countries 2022; (16(6)):1113-1117 doi:10.3855/jidc.15662.

    PMID: 35797308
  22. 22

    Congenital syphilis: the re-emergence of a forgotten disease.

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    BMJ case reports 2024; (17(1)) doi:10.1136/bcr-2023-257694.

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  23. 23

    Increase in congenital syphilis in a tertiary-care centre from Madrid, Spain: Back to the classics.

    Maldonado-Barrueco A, Sanz-González C, Falces-Romero I, et al.

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  24. 24

    Long bone radiographic abnormalities of congenital syphilis in a preterm infant.

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    PMID: 35078780

This page is for informational purposes only and does not replace professional medical advice. Always consult your pediatrician immediately if you suspect your baby has been exposed to syphilis or is showing symptoms.

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