Explaining a positive antenatal syphilis screen — OSCE

Candidate instructions (8-minute station)

You are the paediatric or neonatal registrar meeting a woman in the antenatal clinic. She is 24 years old and 30 weeks pregnant. Her routine antenatal blood test has come back positive for syphilis. She is well and has no symptoms, and the pregnancy has been otherwise uncomplicated. She is frightened and worried about the baby, and she is upset and anxious about the stigma of a sexually transmitted infection. [11]

Your tasks are: [6]

1. Explain what the positive syphilis test means and what syphilis is, in plain, non-stigmatising language. [6]
2. Explain why she needs treatment now, what the treatment is (benzathine penicillin), and why it must be completed before delivery. [6]
3. Explain the Jarisch-Herxheimer reaction she may experience after treatment, so she is not frightened by it. [13]
4. Explain the plan for checking the baby after birth, partner testing and treatment, and how this is all preventable. [11]

You are not expected to manage her penicillin allergy yourself — flag that, if she reports one, the maternity team will arrange a safe alternative path. Use a trained interpreter if needed. [6]

Examiner prompt to the actor (patient)

"Is my baby going to be sick? I didn't even know I had this — how did I get it? Does this mean my partner has been cheating? And you want to give me an antibiotic now — is it safe for the baby? I've heard penicillin can be dangerous in pregnancy. Will my baby need to be in the special care nursery? I'm so embarrassed — I don't want anyone to know." [11]

Marking domains

• Frame and explanation (3): explains syphilis as a treatable bacterial infection detected by routine screening, names that she is well now, and frames the positive test as an opportunity to prevent harm to the baby — in plain, non-judgemental, non-stigmatising language; normalises screening and avoids blame. [6]
• Treatment and timing (3): explains that immediate benzathine penicillin treatment is safe in pregnancy and is the most effective way to prevent the baby being affected, that the full course needs to be finished at least four weeks before delivery, and that the maternity team will confirm the right dose for her stage; addresses the penicillin-safety worry directly. [6]
• The reaction and the neonatal plan (2): explains that she may feel briefly feverish and achy with some tightenings after treatment (the Jarisch-Herxheimer reaction), which is expected and self-limiting; explains that the baby will be examined and have a blood test after birth, and that a well baby whose mother was fully treated may not need intensive treatment. [13]
• Partner, prevention and communication (2): explains that her partner needs testing and treatment to prevent reinfection, that all of this is confidential, and that this is exactly why routine antenatal screening exists — to find and treat before the baby is harmed; checks understanding and addresses her embarrassment and the relationship worry sensitively without speculation about fidelity. [11]

Model answer — the explanatory script

"Thank you for coming in. I want to take this slowly and answer every question you have. The blood test you had at the clinic has come back positive for an infection called syphilis. I know that word can sound frightening, and I know it's an infection people associate with stigma — but I want you to hear the most important thing first: this is a bacterial infection, it is completely treatable, and because we found it on your routine screening test, we can treat it now and protect your baby. That is exactly what the test is for." [6]

"Syphilis is a bacterial infection that, if it's not treated in pregnancy, can pass across the placenta to the baby and cause serious problems — prematurity, or infection in the baby after birth. The good news is that we've found it before any of that has happened, you're well, and there is a very effective antibiotic that cures the infection and stops it reaching the baby. That antibiotic is penicillin — a single injection in most cases — and it is safe in pregnancy. I know people worry about medicines in pregnancy, but penicillin is one of the oldest and safest antibiotics we use, and it is the best treatment for this. We'll arrange the right dose for you with the maternity team today." [6]

"There's one thing I want you to expect, so it doesn't take you by surprise. Within a few hours of the injection, you may feel a bit feverish and achy, almost like a mild flu, and you might notice some tightenings in your tummy. That's called a Jarisch-Herxheimer reaction, and it's actually a sign that the antibiotic is working — the bacteria are dying off. It's short-lived, it settles on its own, and we'll keep an eye on you and the baby while it happens. It is not an allergic reaction, and it doesn't mean the treatment is wrong." [13]

"When your baby is born, we'll do a careful check and a blood test to make sure the treatment has done its job. Because you're being treated well before your due date, there's a very good chance your baby will be well and may not need any intensive treatment — but we always check to be certain. And we'll want to make sure your partner is tested and treated too, so that you don't get reinfected; that's a routine part of care, and it protects you and any future pregnancies." [11]

"On your question about how this happened — syphilis is a common infection, and finding it on a routine test doesn't tell us anything about you as a person, or about your relationship. It's passed on through sexual contact, but it can sit quietly in the body for a long time without causing symptoms, so it's not something to be embarrassed or ashamed about, and it's completely confidential. What matters is that we've found it, we can treat it, and we're going to protect your baby. That's the whole reason we screen every pregnancy." [6] [11]