History Taking · Intermediate · Haematology

Fatigue and Numbness in a 62-Year-Old Woman

Practise this PLAB 2 history taking station on Vitamin B12 Deficiency Anaemia. 8-minute voice AI simulation with feedback on all 3 marking domains.

Clinical scenario

You are an FY2 doctor in a GP surgery. Mrs Isabel Meredith, a 62-year-old woman, presents with six months of progressive fatigue and paraesthesia in her feet. Recent bloods show macrocytic anaemia with low vitamin B12. Please take a focused history to determine the cause of B12 deficiency and discuss management.

Background notes: PMH: Osteopenia, GORD, Hypertension, Hypercholesterolaemia

What this station tests

  • Identifying the cause of B12 deficiency: pernicious anaemia (most likely), long-term PPI use, or dietary insufficiency
  • Recognising neurological involvement: foot paraesthesia as early subacute combined degeneration, which is reversible if treated promptly
  • Intrinsic factor antibodies as the confirmatory test for pernicious anaemia
  • Explaining lifelong treatment: hydroxocobalamin injections every 3 months if pernicious anaemia is confirmed
  • Reviewing PPI use: long-term omeprazole as a contributing factor to B12 malabsorption

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

B12 deficiency stations test whether the candidate can identify the cause (not just treat the deficiency), recognise neurological complications, and communicate the need for lifelong treatment if pernicious anaemia is confirmed. Mrs Meredith is 62, presenting with 6 months of progressive fatigue and foot paraesthesia. Bloods show macrocytic anaemia with low B12. Open with: 'Mrs Meredith, your blood tests have shown why you have been feeling so tired. Let me explain what we have found.'

Core approach

Explain the results clearly. 'Your blood test shows you are anaemic, which means you do not have enough red blood cells to carry oxygen efficiently. The cause is low vitamin B12. B12 is essential for making red blood cells and also for keeping your nerves healthy, which is why you have been getting the tingling in your feet.'

Identify the cause. She eats a normal diet (not vegan), so dietary deficiency is unlikely. She has been on long-term PPI (omeprazole for GORD), which can reduce B12 absorption. However, the most common cause in a well-nourished older woman is pernicious anaemia (autoimmune destruction of intrinsic factor). Check: any family history of autoimmune conditions? Any vitiligo, thyroid disease? Request intrinsic factor antibodies to confirm pernicious anaemia.

Assess neurological involvement. The foot paraesthesia indicates subacute combined degeneration of the spinal cord is a risk if untreated. Ask about balance, gait, proprioception, and cognitive changes. Neurological damage can be irreversible if treatment is delayed, so prompt treatment is essential. Ask: is she unsteady? Has she noticed memory changes? Any falls?

PPI use: long-term omeprazole reduces B12 absorption. This should be reviewed: is the PPI still needed, and can the dose be reduced?

Closing and safety netting

Treatment: B12 replacement injections. If pernicious anaemia is confirmed, treatment is lifelong (intramuscular hydroxocobalamin: loading doses every other day for 2 weeks, then every 3 months for life). If PPI-related or dietary: oral B12 supplementation may suffice after loading. She will likely feel significantly better within weeks as the anaemia corrects.

Address the neurological symptoms: 'The tingling in your feet should improve with treatment, but the sooner we start, the better the chance of full recovery.' If there are significant neurological signs, more intensive loading is needed. Check folate levels too (folate deficiency can coexist and masking folate deficiency while treating B12 alone can worsen neurological damage).

Safety net: 'If the tingling gets worse, you become unsteady on your feet, or you develop new symptoms like difficulty walking, come back urgently.' Follow-up: check FBC at 8 weeks to confirm response.

How examiners mark this station

Examiners will focus on the thoroughness and structure of your history taking for vitamin b12 deficiency anaemia. 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: B12 deficiency cause investigated: diet, PPI use, autoimmune history. Intrinsic factor antibodies requested. Neurological assessment: paraesthesia severity, balance, gait, cognition. PPI review. Folate checked.

Costs marks: Not investigating the cause. Not requesting IF antibodies. Not assessing neurological involvement. Not reviewing PPI.

Domain 2: Clinical Management Skills (Primary focus)

Scores well: B12 replacement initiated (loading doses then maintenance). Lifelong treatment explained if PA confirmed. Neurological urgency recognised. PPI review planned. Folate checked. Follow-up FBC at 8 weeks.

Costs marks: Oral B12 for suspected PA. Not explaining lifelong treatment. Not recognising neurological urgency. No follow-up.

Domain 3: Interpersonal Skills (Throughout)

Scores well: Connecting the diagnosis to her symptoms (fatigue and tingling explained). Providing hope about treatment response. Addressing her concern about the paraesthesia. Clear timeline for improvement.

Costs marks: Not connecting symptoms to diagnosis. Being vague about prognosis. Not addressing the tingling specifically.

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 the deficiency without identifying the cause. Prescribing B12 without checking intrinsic factor antibodies means the underlying diagnosis is missed. If it is pernicious anaemia, she needs lifelong injections. If PPI-related, dose reduction may be sufficient.
  2. Not recognising the neurological urgency. Foot paraesthesia from B12 deficiency indicates early spinal cord involvement. If treatment is delayed, neurological damage can become irreversible. Candidates who treat this as routine anaemia miss the urgency.
  3. Not reviewing the PPI. Long-term omeprazole reduces B12 absorption. Candidates who do not question whether the PPI is still needed miss a modifiable contributing factor.

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 vitamin B12 deficiency anaemia history in this PLAB 2 station?

B12 deficiency stations test whether the candidate can identify the cause (not just treat the deficiency), recognise neurological complications, and communicate the need for lifelong treatment if pernicious anaemia is confirmed. Mrs Meredith is 62, presenting with 6 months of progressive fatigue and foot paraesthesia. Bloods show macrocytic anaemia with low B12.

What are examiners marking in this vitamin B12 deficiency anaemia station?

Marks are won for: B12 deficiency cause investigated: diet, PPI use, autoimmune history. Intrinsic factor antibodies requested. Neurological assessment: paraesthesia severity, balance, gait, cognition. Marks are lost for: Not investigating the cause. Not requesting IF antibodies. Not assessing neurological involvement. Not reviewing PPI.

What is the most common mistake candidates make in this vitamin B12 deficiency anaemia station?

Treating the deficiency without identifying the cause. Prescribing B12 without checking intrinsic factor antibodies means the underlying diagnosis is missed. If it is pernicious anaemia, she needs lifelong injections.

How do I prepare for this station if I have not managed vitamin B12 deficiency anaemia in clinical practice?

This station rewards process over personal experience. The skill being assessed: Recognising neurological involvement: foot paraesthesia as early subacute combined degeneration, which is reversible if treated promptly. The written guidance on this page covers the full approach, and practising the consultation aloud builds the fluency the examiner is listening for.

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