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CME Credit Offered
CME Credit Offered
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Abstract Award
Recording available 2/16-5/2
Recording available 2/16-5/2
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AIUM Credit
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Foundation Awardee
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Abstract Award
Abstract Award
Foundation Awardee
Foundation Awardee

Poster Session 3

Category: Infectious Diseases

Poster Session 3

(938) Ultrasound to predict congenital syphilis risk despite BPG: a tool, not a management strategy

Thursday, February 12, 2026
10:30 AM - 12:00 PM  
Objective:
Characterize and compare congenital syphilis (CS) outcomes among pregnancies with and without any abnormal ultrasound (US) findings prior to initiation of benzathine penicillin G (BPG).

Study Design:
Retrospective chart review of maternal syphilis diagnosed ≥18 weeks at a large public hospital. Among those with US for CS before BPG administration, we documented placentomegaly, polyhydramnios, hepatomegaly, ascites, and elevated MCA systolic velocity ( >1.5MoM). We compared syphilis characteristics and US findings among those with and without US abnormalities, and grouped isolated versus combinations of US findings with liveborn congenital syphilis outcomes.

Results:

From Jan 2010 through June 2025, 307 were diagnosed with syphilis ≥18 weeks; not all had US for CS findings. Of 125(40.7%) with US for CS, 119(95%) received BPG before delivery. Of those with US, 61(48.8%) had at least one finding of CS (hepatomegaly [67%]; placentomegaly [52%], MCA >1.5MoM [25%], polyhydramnios [8%], and ascites [7%]); 64(51.2%) had no abnormal US findings and most were treated in the clinic. There was no difference in maternal syphilis stage or initial RPR among those with vs without abnormal US. CS was higher among fetuses with at least hepatomegaly (OR 5.27, 95%CI, 2.05-14.5), but less likely if hepatomegaly was isolated or with one other finding, suggesting BPG was more likely to be effective before delivery. When multiple US abnormalities were identified in the late second or early third trimester, CS was frequent despite BPG. CS occurred in 2/2 stillborn and 2/2 of liveborn with ascites, suggesting this was a late finding and less reversible by BPG before delivery occurred.

Conclusion:
Most ultrasounds after 18 weeks in gravidas with syphilis are normal, facilitating efficient treatment outpatient. When US demonstrates combinations of multiple CS-associated abnormalities (particularly ascites) in the late second or early third trimester, BPG may not be successful in preventing a CS outcome before delivery occurs.