History Taking · Foundation · Infectious Diseases

Painless Genital Ulcer in a 34-Year-Old Man

Practise this PLAB 2 history taking station on Primary Syphilis. 8-minute voice AI simulation with feedback on all 3 marking domains.

Clinical scenario

You are an FY2 doctor in a sexual health clinic. Mr Winston Lawson, a 34-year-old man, has come to see you with a painless ulcer on his penis that appeared three weeks ago. He is concerned about what this might be and is keen to understand testing and treatment options. Please take a focused sexual history and discuss investigation and management.

Background notes: PMH: Appendicitis (appendectomy at age 22), Otherwise fit and well

What this station tests

  • Painless genital ulcer as the hallmark of primary syphilis: painless distinguishes from herpes (painful vesicles) and chancroid (painful ulcer)
  • Single dose IM benzathine penicillin as first-line treatment for primary syphilis
  • Jarisch-Herxheimer reaction warning: fever, headache, myalgia within 24 hours of treatment, self-resolving
  • Partner notification as mandatory public health requirement: contact, test, and treat
  • Follow-up serology at 3, 6, 12 months: RPR titre decline confirms treatment response

How to use your 8 minutes

  • 0-1 min — Introduction: Introduce yourself, confirm identity, open question. 'What's brought you in today?'
  • 1-4 min — Systematic History: Presenting complaint detail (SOCRATES for pain, timeline, severity). Systems review. PMH, medications, allergies.
  • 4-6 min — Context and ICE: Social history (smoking, alcohol, occupation, living situation). Family history. Ideas, Concerns, Expectations.
  • 6-7 min — Summary and Plan: Summarise findings back to patient. Share differential/working diagnosis. Outline investigation and management plan.
  • 7-8 min — Closing: Safety netting with specific red flags. Arrange follow-up. Check for questions.

Consultation approach

The opening

A painless genital ulcer is syphilis until proven otherwise. The candidate must take a sexual history, arrange appropriate testing, provide treatment, and initiate partner notification. Mr Lawson is 34, recently separated, presenting with a painless penile ulcer for 3 weeks. Open with: 'Mr Lawson, thank you for coming in. A painless ulcer like this needs investigation. Tell me about what you have noticed.'

Core approach

Characterise the ulcer. Painless (the key distinguishing feature), single, indurated (firm), well-demarcated, on the penile shaft, present for 3 weeks. No discharge, no multiple vesicles (excludes herpes), no pain (excludes chancroid). This is a classic syphilitic chancre. Inguinal lymphadenopathy may be present (tender, mobile, discrete).

Sexual history. Recently separated, now dating. Unprotected sex with a new partner approximately 4 weeks ago. The 3-week incubation fits (chancre appears 10 to 90 days after exposure, median 21 days). Ask about MSM (men who have sex with men) activity, number of partners, previous STIs.

Testing: syphilis serology (RPR or VDRL as screening, confirmed with FTA-ABS or TPHA). Dark-field microscopy of the chancre (if available, can provide immediate diagnosis). Offer full STI screen: HIV, hepatitis B/C, gonorrhoea, chlamydia. HIV co-testing is particularly important as syphilis facilitates HIV transmission.

The chancre will heal spontaneously in 3 to 12 weeks even without treatment, but the infection progresses to secondary syphilis. Treatment must not wait for the chancre to resolve.

Closing and safety netting

Treatment: single dose IM benzathine penicillin G 2.4 million units (first-line for primary syphilis). If penicillin allergic: doxycycline 100mg BD for 14 days. Warn about the Jarisch-Herxheimer reaction: 'Within 24 hours of treatment you may develop fever, headache, and muscle aches. This is a normal reaction and resolves within 48 hours.'

Partner notification: the recent sexual partner must be contacted, tested, and treated. The sexual health clinic can assist with anonymous notification. Abstain from sex until treatment is complete and follow-up serology shows response.

Follow-up: repeat serology at 3, 6, and 12 months to confirm treatment response (RPR titre should decline fourfold). Safety net: 'If you develop a widespread rash, mouth ulcers, or patchy hair loss in the coming weeks, come back urgently as these could indicate the infection progressing.' GUM clinic referral for specialist follow-up.

How examiners mark this station

Examiners will focus on the thoroughness and structure of your history taking for primary syphilis. Domain 1 (Data Gathering) carries the most weight: expect marks for systematic coverage of presenting complaint, red flags, PMH, medications, social and family history. Domain 2 (Clinical Management) requires a clear differential, appropriate investigations, and a safe management plan with safety netting. Domain 3 (Interpersonal Skills) is assessed throughout: genuine exploration of ICE, active listening, empathic responses, and clear communication without jargon.

Domain 1: Data Gathering, Technical and Assessment Skills (Primary focus)

Scores well: Painless ulcer characterised (indurated, single, well-demarcated). Sexual history taken. Incubation period fits. Full STI screen including HIV offered. Lymphadenopathy checked.

Costs marks: Not noting painlessness. No sexual history. No full STI screen. Not offering HIV test.

Domain 2: Clinical Management Skills (Primary focus)

Scores well: IM benzathine penicillin prescribed. Jarisch-Herxheimer warned. Partner notification arranged. Follow-up serology at 3/6/12 months. Secondary syphilis safety netting. GUM referral.

Costs marks: Wrong antibiotic. No JH warning. No partner notification. No follow-up serology.

Domain 3: Interpersonal Skills (Throughout)

Scores well: Non-judgmental about sexual activity. Sensitive partner notification discussion. Explaining syphilis without stigma. Confidentiality established.

Costs marks: Judgmental. Making partner notification feel punitive. Stigmatising. Not establishing confidentiality.

Common examiner feedback (and how to fix it)

Did not gather sufficient information to make an adequate assessment of the patient's condition

Fix: Use a consistent framework for every history. After covering the presenting complaint, systematically move through PMH, drug history, social history, family history, and ICE. Keep a mental checklist.

Did not identify the patient's problems and/or did not develop a management plan adequately

Fix: Reserve the final 2 minutes to summarise your findings, share your working diagnosis with the patient, and outline your investigation and management plan including safety netting.

Common mistakes in this station

  1. Not recognising the painless ulcer as syphilis. The painlessness is the diagnostic clue. Herpes causes painful vesicles. Chancroid causes painful ulcers. Candidates who do not note the painless nature miss the key differential.
  2. Not warning about Jarisch-Herxheimer reaction. Patients who develop fever after treatment may think the antibiotic has caused a new infection and stop treatment. Warning them in advance prevents this.
  3. Not arranging partner notification. Syphilis is a notifiable disease and partner tracing is essential. Candidates who treat without addressing the sexual partner allow ongoing transmission.

Resitting PLAB 2?

If you have previously struggled with history taking stations, focus on building a consistent systematic framework that you apply to every case. Practise structuring your history into clear phases (presenting complaint, systems review, PMH, social, ICE) so that even under pressure, you cover all domains. Many resitters lose marks not on knowledge but on organisation and time management.

Example opening

Good morning/afternoon, my name is Dr [Name], I'm one of the doctors here today. Could I confirm your name and date of birth please? Thank you. So, what's brought you in to see me today?

Frequently asked questions

How should I structure the primary syphilis history in this PLAB 2 station?

A painless genital ulcer is syphilis until proven otherwise. The candidate must take a sexual history, arrange appropriate testing, provide treatment, and initiate partner notification. Mr Lawson is 34, recently separated, presenting with a painless penile ulcer for 3 weeks.

What are examiners marking in this primary syphilis station?

Marks are won for: Painless ulcer characterised (indurated, single, well-demarcated). Sexual history taken. Incubation period fits. Full STI screen including HIV offered. Marks are lost for: Not noting painlessness. No sexual history. No full STI screen. Not offering HIV test.

What is the most common mistake candidates make in this primary syphilis station?

Not recognising the painless ulcer as syphilis. The painlessness is the diagnostic clue. Herpes causes painful vesicles.

How do I prepare for this station if I have not managed primary syphilis in clinical practice?

Structure beats experience here. Focus on single dose IM benzathine penicillin as first-line treatment for primary syphilis. Work through the consultation approach above, then rehearse it aloud under the 8-minute time pressure so the structure holds up in the exam.

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