History Taking · Foundation · Infectious Diseases

Intense Itching Worse at Night in a 42-Year-Old Woman

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

Clinical scenario

You are an FY2 doctor in general practice. Mrs Elena Kazakov, a 42-year-old woman, has come to see you with intense itching that is worse at night. She describes the itching as unbearable, particularly on her wrists, between her fingers, and on her breasts. She has noticed similar symptoms in her family. Please take a focused history and discuss diagnosis and management.

Background notes: PMH: Hay fever (seasonal allergies), Otherwise fit and well

What this station tests

  • Distribution pattern: finger webs, wrists, breasts, lower abdomen, genitals with nocturnal predominance
  • Simultaneous treatment of ALL household contacts: even asymptomatic members, otherwise reinfection occurs
  • Two applications 7 days apart: the second application kills mites hatched from eggs that survived the first
  • Post-scabies itch: itching persists 2-4 weeks after successful treatment from immune response to dead mites
  • Decontamination: hot wash bedding/towels, seal non-washable items for 72 hours

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

Intense nocturnal itching affecting multiple household members is scabies until proven otherwise. The candidate must identify the distribution pattern, treat the patient AND all household contacts simultaneously, and provide practical decontamination advice. Mrs Kazakov is 42, with 4 weeks of unbearable nocturnal itching. Her husband and one child are also itching. Open with: 'Mrs Kazakov, the fact that your family members are also affected is an important clue. Tell me about the itching.'

Core approach

The distribution is diagnostic. Itching worst in the finger webs, wrists, around breasts, lower abdomen, and genital area. Worse at night (mites are more active in warmth). Duration 4 weeks (consistent with first infestation, where the immune response takes 2 to 6 weeks to develop). She may have noticed tiny linear burrows (pathognomonic) but they are often obscured by excoriation.

Multiple household members affected confirms person-to-person transmission. Her husband is scratching and one child (14 or 11) is also complaining of itching. This household pattern makes scabies almost certain. Ask about the other child: they may also be affected or asymptomatic carriers.

Distinguish from eczema (which she has considered). Eczema: typically in flexures, chronic relapsing, personal or family atopic history. Scabies: finger webs, wrists, genital area, nocturnal predominance, multiple household members, new onset. The distribution and household pattern are the key differentiators.

Ask about close contacts beyond the household: school friends (children), intimate contacts, elderly relatives in care homes.

Closing and safety netting

Treatment: permethrin 5% cream (first-line). Applied to entire body from chin down (including finger webs, under nails, genitals, soles of feet). Leave on for 8 to 12 hours (overnight), then wash off. Repeat after 7 days (to kill newly hatched mites from eggs that survived the first application). Critical: ALL household members must be treated simultaneously, even if asymptomatic, or reinfection will occur.

Decontamination: wash all bedding, towels, and clothing used in the past 3 days on a hot cycle (60C). Items that cannot be washed should be sealed in a bag for 72 hours (mites die without human contact within 72 hours). Explain: itching may persist for 2 to 4 weeks after successful treatment (post-scabies itch from immune reaction to dead mites). This does not mean treatment has failed.

School: children can return after the first treatment application. Safety net: 'If itching is not improving after 4 weeks, or new burrows appear, come back as re-treatment may be needed.' Antihistamine (cetirizine) for symptomatic itch relief.

How examiners mark this station

Examiners will focus on the thoroughness and structure of your history taking for scabies. 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: Diagnostic distribution identified. Nocturnal predominance noted. Household members affected (confirms transmission). Burrows sought. Differentials excluded (eczema, contact dermatitis). All contacts assessed.

Costs marks: Not identifying the distribution. Not asking about household members. Misdiagnosing as eczema.

Domain 2: Clinical Management Skills (Primary focus)

Scores well: Permethrin 5% prescribed correctly. Two applications 7 days apart. All household contacts treated. Decontamination advice. Post-scabies itch explained. School return advice. Antihistamine for symptomatic relief.

Costs marks: Treating patient only. Single application. No decontamination. Not explaining post-treatment itch.

Domain 3: Interpersonal Skills (Throughout)

Scores well: Not implying poor hygiene. Practical, clear instructions for the whole family. Reassuring about treatability. Explaining post-treatment itch to prevent unnecessary anxiety.

Costs marks: Implying hygiene issue. Overwhelming with information. Not explaining post-treatment itch.

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. Treating only the patient. All household contacts must be treated simultaneously. Treating Mrs Kazakov alone will result in reinfection from her untreated husband and children within days.
  2. Not advising the second application at 7 days. Permethrin kills mites but not all eggs. The second application at 7 days catches newly hatched mites. Candidates who prescribe a single application allow treatment failure.
  3. Interpreting persistent itch as treatment failure. Post-scabies itch (immune reaction to dead mites) lasts 2 to 4 weeks after successful treatment. Candidates who re-treat based on persistent itch alone over-treat.

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

What is the best way to take a scabies history in PLAB 2?

Intense nocturnal itching affecting multiple household members is scabies until proven otherwise. The candidate must identify the distribution pattern, treat the patient AND all household contacts simultaneously, and provide practical decontamination advice. Mrs Kazakov is 42, with 4 weeks of unbearable nocturnal itching.

Where are marks won and lost in this scabies station?

Examiners reward: Diagnostic distribution identified. Nocturnal predominance noted. Household members affected (confirms transmission). Burrows sought. Differentials excluded (eczema, contact dermatitis). Candidates are penalised for: Not identifying the distribution. Not asking about household members. Misdiagnosing as eczema.

Where do candidates most often go wrong in this station?

Treating only the patient. All household contacts must be treated simultaneously. Treating Mrs Kazakov alone will result in reinfection from her untreated husband and children within days.

Can I do well in this station without real-world experience of scabies?

This station rewards process over personal experience. The skill being assessed: Simultaneous treatment of ALL household contacts: even asymptomatic members, otherwise reinfection occurs. 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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