Station 45
Sarah Burkitt
Age: 32 years old female
Examiner
Marking Scheme
Data Gathering and Diagnosis
- Ask about tiredness — whether it has changed or worsened since the last consultation with the colleague
- Ask about associated B12 deficiency symptoms: Memory problems or difficulty concentrating (possible cognitive changes from B12 deficiency), headache, blurred vision (possible optic neuropathy), mouth ulcers (e.g. angular cheilitis), tingling or numbness in hands/feet or other parts of the body (peripheral neuropathy due to B12 deficiency), palpitations, chest pain, or shortness of breath (anaemia-related symptoms)
- Ask about gastrointestinal symptoms that may suggest malabsorption — e.g. diarrhoea, bloating, vomiting (to consider underlying cause, especially as patient is taking oral supplements and B12 levels are still low)
- Ask about any personal or family history of autoimmune conditions (e.g. pernicious anaemia)
- Ask about dietary habits — whether the patient is vegan or vegetarian
- Ask how the tiredness is affecting her daily life (function, work, wellbeing)
- Ask social history, including smoking, alcohol, recreational drug use (especially nitrous oxide, which can inactivate B12) and occupation
- Ask about any prescribed medications (e.g. metformin, PPIs) not listed on patient’s note, or over-the-counter medications (e.g. OTC esomeprazole)
- Give a diagnosis of anaemia caused by B12 and folate deficiency.
Example of explanation to patient
Sarah, I’ve had a look at your blood results, and I think we’ve found a reason why you’ve been feeling so tired.
Your haemoglobin, which is the part of your blood that carries oxygen around your body, is a bit low — this is called anaemia. That could definitely explain your tiredness.
Now, we’ve also found that your vitamin B12 and folate levels are very low, and that’s likely the main reason your haemoglobin is low. B12 and folate are important vitamins that help your body make healthy red blood cells.
I know you’ve been taking supplements and eating well, so the fact that your levels are still low makes me wonder whether your body is struggling to absorb B12 from food or tablets. One possible cause is something called pernicious anaemia, where the immune system accidentally affects your stomach’s ability to absorb B12. If this is the case, you might need B12 injections instead of tablets, and possibly long term.
So, what we’ll do next is arrange a blood test to check for pernicious anaemia. This will help us find the exact cause and guide the best treatment.
In the meantime, because your B12 level is very low and you’re showing symptoms, I’d recommend we start you on B12 injections, which will be more effective than tablets as it seems the tablets aren’t working. The injections will usually be given three times a week for two weeks to begin with, and then we reassess. If we find a long-term absorption problem like pernicious anaemia, these may need to be continued regularly for life, but we’ll discuss that based on the results of your further tests.
We’ll start the folate treatment after the B12 course has begun, as it’s important not to treat folate alone when B12 is very low.
I’ll also arrange follow-up blood tests about 7–10 days after starting the injections, to check that your blood count is improving, and again after 8 weeks, to monitor your progress.
You mentioned it’s affecting your work, and I completely understand that. If you need, I can provide a fit note or amended duties note for your employer while we begin treatment.
Lastly, if you notice any new symptoms like tingling in your hands or feet, balance problems, or changes in your memory or mood, please seek urgent medical advice — these can be signs that the nerves are being affected.
Management
- Offer a blood test for intrinsic factor antibodies to assess for pernicious anaemia. If this is normal, refer to gastroenterology for further tests such as a gastroscopy and colonoscopy to check for gut-related causes of malabsorption. If those are also normal, refer to haematology for further specialist evaluation.
- Start treatment with Vitamin B12 (Hydroxocobalamin) injections at a dose of 1 mg intramuscularly three times a week for 2 weeks. Folate replacement can be initiated after B12 treatment has started, typically 24 to 48 hours later.
- Arrange a full blood count and reticulocyte count within 7–10 days of starting treatment to check for response and repeat again after 8 weeks to confirm ongoing improvement.
- Explain that if no reversible cause is found, treatment with B12 injections may be lifelong.
- Advise she should continue eating food rich in b12 and folate.
- Offer a Fit Note with amended duties or workplace adjustments, as the patient’s symptoms are currently impacting their ability to work
- Safety net and advise the patient to seek urgent medical attention if they develop new symptoms such as tingling in the hands or feet, balance problems, or changes in memory or mood, as these may indicate nerve involvement.
Learning point from this station:
Deficiency of vitamin B12 or folate is the most common cause of megaloblastic anaemia. In the UK, pernicious anaemia is the leading cause of severe B12 deficiency. Other causes include:
- Drugs (e.g. metformin, colchicine, proton pump inhibitors)
- Intestinal causes (e.g. malabsorption, ileal resection, Crohn’s disease)
- Nutritional causes (e.g. malnutrition, vegan diet)
When a patient continues to have low B12 levels despite taking oral supplements, this should raise suspicion of malabsorptionas the underlying issue.
It is essential during history-taking to ask about possible neurological complications such as ataxia, paraesthesia, visual changes (e.g. optic neuropathy), and cognitive decline or loss of physical drive. If any of these are present, urgent specialist advice from a neurologist and/or haematologist should be sought.
If immediate specialist input is unavailable, treatment should begin with hydroxocobalamin 1 mg intramuscularly on alternate days until there is no further improvement, then switch to 1 mg every 2 months for maintenance.
When both B12 and folate deficiencies are present, B12 should be started first. Folate can usually be added 24–48 hours after B12 replacement has begun, to avoid the risk of worsening or unmasking neurological complications.