Skip to main content
STI 2024 Prevention Conference Main banner
Final Program


Abstract Book
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.

Poster Session I: Congenital Syphilis & Syphilis in Pregnancy

(P9) ECHOES OF THE PAST: EXPLORING DELAYED DIAGNOSIS OF CONGENITAL SYPHILIS IN THE LAST 20 YEARS

Tuesday, September 17, 2024
4:15 PM - 5:15 PM EST
Background:
Congenital syphilis (CS) is usually diagnosed at delivery through documentation of inadequate treatment of the birthing parent or presence of signs/symptoms of infection in the neonate; however, congenital infection may be diagnosed months/years after delivery, delaying treatment and potentially resulting in serious clinical complications. Using national CS case notification data, we investigated delayed diagnoses of congenital infection in the United States.

Methods:
We reviewed CS case notifications provided to CDC through the National Notifiable Diseases Surveillance System as of March 2024. To allow for 15 months of follow-up, we identified CS cases with birth years 2003-2022, determined the likely date of infant diagnosis based on earliest infant laboratory date, and described those with a delayed diagnosis (defined as ≥6 months after delivery).

Results:
Of the 18,971 CS cases with a birth year of 2003-2022, 13,329 (70%) had information available to estimate diagnosis date. Of those 13,329 cases, 60 (0.5%) had a delayed diagnosis; 25% of these were born in the most recent 2 years (2021-2022). Of delayed diagnoses, the mean age at diagnosis was 16 months (IQR: 8-17 months); 18 cases were diagnosed at 12–23 months, and 7 cases at ≥24 months. Among delayed diagnoses, the largest proportion of cases were in the Midwest (30%) and 20% had radiographic long bone findings consistent with CS, the most frequent non-laboratory sign of CS. Of the 42 cases with a reported titer, the mode was 1:128. Overall, 93% of delayed diagnoses were reported as treated.

Conclusion:
Although diagnosis of CS can occur months to years after delivery, late diagnosis is rare in the United States. Further investigation into delayed diagnoses is needed to understand root causes, including lack of testing in the birth parent or infant at delivery, incubating syphilis at delivery, or breakthrough cases where the pregnant person was appropriately treated.