Cases/Haematology

Tiredness, Macrocytic Anaemia, and Hypercholesterolaemia — Free SCA Practice Case

Woman with tiredness, macrocytic anaemia, and hypercholesterolaemia

Station Timer

12:00

Golden Minute

Initial Introduction

•Introduce yourself

•Ask an open question — "How can I help you today?"

•Listen — don't interrupt

•Catch early cues

Data Gathering

History, ICE & Diagnosis

Clinical Management

Diagnosis, Plan & Decisions

Safety Net

Follow-up & Close

12:00

Golden Minute

Materials for Candidate

Please review before starting the consultation

Patient Profile

Full Name

Susan Davies

Age

52 years

Consultation Type

Video

Age

52 (DOB: 12/04/1973)

Situation

Video Consultation.

Reason for Encounter

"Follow-up to discuss recent blood test results. Patient initially presented 2 weeks ago with profound tiredness and lethargy."

Medical Records

●PMH: Nil significant.
●Medications: None.
●Allergies: NKDA.

Recent Notes

●Blood Results (Returned yesterday):
●FBC: Hb 104 g/L (Low), MCV 106 fL (High - Macrocytic).
●Haematinics: B12 normal, Folate normal, Ferritin normal.
●Lipids: Total Cholesterol 7.8 mmol/L (High), Triglycerides 2.4 mmol/L.
●U&Es / LFTs / HbA1c: Normal.
●TFTs: TSH 38.5 mU/L (High), Free T4 6.2 pmol/L (Low).

Patient Script

For the friend playing the patient role

Character Overview: You are Susan.

You are utterly exhausted. You struggle to get out of bed, your brain feels "foggy", and you've been feeling miserable for months. You looked at your NHS app this morning and saw the red exclamation marks next to "Anaemia" and "High Cholesterol." You are highly anxious. You think the anaemia means you have a blood cancer, and the high cholesterol means you are going to have a heart attack. Opening Sentence: "Hello Doctor. Thank you for calling. I saw my blood results on the app this morning and I've been in a state all day. It says I'm anaemic and my cholesterol is through the roof. With how exhausted I feel, is it something serious? Do I have leukaemia? Am I going to have a heart attack?"

History if Asked (Data Gathering Phase)

●The Fatigue: "I feel so exhausted. I sleep for 10 hours and wake up exhausted."
●
Hypothyroid Symptoms (The Clues):
- ●Temperature: "I am freezing all the time. I have the heating on and I'm wearing a fleece while my husband is in a t-shirt."
- ●Weight: "I've put on about a stone in the last 6 months, even though I hardly have the appetite to eat."
- ●Bowels: "I'm very constipated. I only go maybe twice a week now."
- ●Skin/Hair: "My skin is like sandpaper, and my hair is definitely thinning out."
- ●Menstruation: "My periods stopped about a year ago. I just assumed all this was the menopause."
●
Red Flags (Rule out other causes):
- ●"No blood in my poo, no black stools." (Ruling out GI bleed for anaemia, though MCV is high, not low).
- ●"No night sweats, no lumps or bumps."

ICE — Ideas, Concerns, Expectations

●
Ideas: Susan is convinced she has two serious, separate problems. She saw the red flags on her NHS app and has jumped to the worst conclusions — she thinks the anaemia means she has leukaemia or some kind of blood cancer, and the high cholesterol means she is at imminent risk of a heart attack. She has no awareness of thyroid disease and has never considered that all her symptoms could be connected by a single cause. If the candidate explores her thinking, she will say: "I looked it up online and anaemia can be a sign of cancer, can't it? And cholesterol that high — that's heart attack territory. I've been sitting here all day thinking I'm falling apart."
●
Concerns: Her deepest worry is that she has something life-threatening and that she's been ignoring it for months by putting everything down to the menopause. She is also worried about the impact on her family — she has two teenage children and feels she has been "useless" to them for months. If asked directly: "I'm terrified, honestly. I keep thinking — what if I'd come in sooner? What if something's been brewing and I've just been ignoring it? My kids need me. I can't be ill."
●
Expectations: Susan wants a clear, honest explanation of what the results mean in plain language. She wants to be told whether she has something serious, and if so, what happens next. She is hoping for reassurance but is bracing for bad news. If asked: "I just want you to tell me straight — what's going on with me? And is there something you can actually do about it, or is this something I'm stuck with?"

If Asked — Medical History and Medications

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Past Medical History: "No, I've never really been ill. I've been lucky, to be honest — never had anything serious, no operations, nothing. That's partly why this has scared me so much. I'm not used to being told something's wrong."
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Medications: "No, I don't take anything. Not even a multivitamin. I've never needed to."
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Allergies: "No allergies that I know of."
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Family History (if asked): "My mum had an underactive thyroid, actually — she's been on tablets for years. I never really thought about it. My dad had high blood pressure but he's fine on his tablets. No cancer in the family that I know of."
●
Blood results on the NHS app: "I saw the results come up on my phone this morning. There were red exclamation marks next to a few things — it said anaemia and high cholesterol. I didn't really understand the numbers, but the red marks panicked me. I've been googling ever since and I wish I hadn't."

Social History and Lifestyle Impact

●
Occupation: Susan works as a part-time teaching assistant at a local primary school, three days a week. She enjoys the job and has done it for eight years.
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Family: She is married and has two teenage children (15 and 17). Her husband works full-time as an electrician.
●
Lifestyle impact of the condition: The fatigue has profoundly disrupted Susan's daily life. She should convey this naturally and specifically if the conversation opens up to it:
- ●"I've had to call in sick to school three times in the last month because I physically couldn't get out of bed. I've never done that before — I feel awful about it. The other staff are covering for me and I can see they're getting fed up."
- ●"At home I'm useless. The kids come in from school and I'm asleep on the sofa. My husband's been doing all the cooking and the washing because I just can't face it. I feel like I'm letting everyone down."
- ●"I used to walk the dog every morning — a good 40 minutes round the park. I haven't managed that in weeks. My husband's had to take over. Even going up the stairs leaves me out of breath now."
●
Alcohol: "I barely drink. Maybe a glass of wine at the weekend, but to be honest I've gone off it recently because it makes me feel even more tired."
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Smoking: "No, I've never smoked."
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Diet: "I try to eat well but I've had no appetite for months. I'm living on toast and tea. My husband keeps telling me I need to eat properly but I just can't face it."

If Asked — Associated Symptoms

●
If asked about mood or depression: "I wouldn't say I'm depressed exactly, but I'm definitely not myself. I feel flat and miserable, but I think that's because I'm so tired all the time, not the other way round. I don't feel hopeless or anything like that — I just want to feel normal again."
●
If asked about muscle aches or joint pain: "Actually, yes — my muscles do ache. My calves especially. I just put it down to not moving enough, but now you mention it, it has been worse lately."
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If asked about neck swelling or a lump in the throat: "No, I haven't noticed anything like that. No lump or swelling."
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If asked about difficulty swallowing: "No, swallowing is fine."
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If asked about voice changes or hoarseness: "I don't think so. My husband hasn't said anything."
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If asked about palpitations or chest pain: "No palpitations. No chest pain. That's partly why the cholesterol result shocked me — I didn't think there was anything wrong with my heart."
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If asked about shortness of breath: "Only when I exert myself — like going up the stairs. But not at rest, no."
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If asked about swelling in the legs or face: "Funny you mention that — my face does look a bit puffy in the mornings. I thought it was just because I'd been sleeping so much. My ankles are fine though."
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If asked about tingling or numbness in the hands: "No, nothing like that."
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If asked about memory or concentration problems: "Yes, definitely. My brain is like mush. I forget what I was saying mid-sentence. At work I have to read things three times before they go in. It's embarrassing."
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If asked about visual changes or headaches: "No headaches, and my eyes are fine."
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If asked about heavy or prolonged periods (before they stopped): "They were getting heavier in the year or so before they stopped, but I assumed that was just perimenopause."
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If asked about bleeding from anywhere: "No, no unusual bleeding at all."
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If asked about alcohol intake in detail: "Barely anything. A glass of wine at the weekend, sometimes not even that. I've never been a big drinker."
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If asked about any dietary restrictions or vegan/vegetarian diet: "No, I eat everything. Well, I used to — I just haven't had much appetite recently."
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If asked about previous stomach or bowel surgery: "No, never had any surgery."
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If asked about bruising easily: "No more than usual, no."
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If asked about fevers or infections: "No fevers. I had a cold a few weeks ago that took ages to shift, but nothing serious."

Responses to Management (The Negotiation Phase)

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If the Doctor explains it is an Underactive Thyroid (Hypothyroidism):
- ●Reaction: "The thyroid? But what about the anaemia and the cholesterol? Are they all connected, or do I have three different diseases?"
●
If the Doctor suggests starting a Statin for the cholesterol:
- ●Reaction: "My friend is on a statin and she gets terrible muscle aches. Do I really need it? Can I not just change my diet?" (Note: Starting a statin here is a clinical error).
●
If the Doctor suggests Iron tablets:
- ●Reaction: "But my iron was normal on the app? Why do I need iron?" (Note: Prescribing iron for macrocytic anaemia is a clinical error).
●
If the Doctor explains Levothyroxine will fix everything:
- ●Reaction: Huge relief. "So one tablet will sort the tiredness, the blood count, and the cholesterol? That makes so much sense. How long will it take to work?"

Mark Scheme

Domain 1: Data Gathering and Diagnosis

0 / 22 indicators checked+0−0

Positive (0/11)

Negative (0/11)

Domain 2: Clinical Management and Medical Complexity

0 / 32 indicators checked+0−0

Positive (0/16)

Negative (0/16)

Domain 3: Relating to Others

0 / 20 indicators checked+0−0

Positive (0/10)

Negative (0/10)

Clinical Learning Points

The Unifying Diagnosis — Recognising the Pattern

This case tests the ability to avoid siloed medicine. The three abnormal results (raised TSH with low fT4, macrocytic anaemia, hypercholesterolaemia) represent a single pathological process, not three separate diagnoses.

●Hypothyroidism and hypercholesterolaemia: Thyroid hormone upregulates hepatic LDL receptor expression. In hypothyroidism, LDL clearance falls, producing secondary hypercholesterolaemia. This is reversible with thyroid replacement — the cholesterol does not require independent treatment.
●Hypothyroidism and macrocytic anaemia: Thyroid hormones stimulate erythropoiesis. Deficiency causes a mild, normochromic macrocytosis (MCV typically 100–110 fL) with normal B12, folate, and ferritin — as seen here. This is a direct haematological consequence of the hypothyroid state and resolves with treatment.
●The diagnostic pitfall: Candidates who treat the results in isolation risk prescribing a statin, initiating iron supplements, or requesting unnecessary specialist referrals — all of which are clinical errors in this case.

Macrocytic Anaemia — Differential and Interpretation

Not all macrocytosis has the same cause. In this case, the key is what is normal as much as what is not.

●Normal B12, folate, and ferritin exclude the commonest nutritional causes — B12 deficiency and folate deficiency — which should always be checked first.
●Other causes of macrocytosis to consider and exclude: alcohol excess (minimal here), liver disease (LFTs normal), haematological malignancy (no night sweats, lymphadenopathy, or weight loss; no cause for suspicion), and medications (e.g. methotrexate, hydroxycarbamide — not applicable here).
●Do not prescribe iron for macrocytic anaemia. Iron deficiency causes microcytic anaemia (low MCV). Prescribing iron for a raised MCV demonstrates a fundamental misreading of the blood results and would not address the underlying cause.

Initiating Levothyroxine (NICE CKS)

●Healthy adults under 65 years with no cardiovascular disease: Start at 50–100 micrograms once daily. For a 52-year-old with no cardiac history (as here), 50 mcg is a reasonable and safe starting point.
●Adults over 65, or those with cardiovascular disease: Start cautiously at 12.5–25 micrograms once daily to avoid precipitating angina or arrhythmia — cardiac demand increases as metabolism normalises.
●Administration: Take on an empty stomach, 30–60 minutes before breakfast or at bedtime (at least 2 hours after the last meal). Absorption is significantly reduced by calcium supplements, iron supplements, and antacids/PPIs — these should be taken at least 4 hours apart.
●This is a lifelong medication. Levothyroxine replaces a hormone the thyroid can no longer produce adequately. Most patients require it indefinitely. Setting this expectation clearly at initiation avoids premature self-discontinuation.

The Statin Trap

Never start a statin in a patient with significant, untreated hypothyroidism.

●Why: Hypothyroidism itself elevates creatine kinase (CK) and causes myalgia. Statins inhibit the mevalonate pathway, impairing mitochondrial function in muscle. In the context of hypothyroidism, this synergy substantially increases the risk of statin-induced myopathy and rhabdomyolysis.
●The current cholesterol does not reflect the patient's true cardiovascular risk. It is artefactually elevated by the hypothyroid state. A formal cardiovascular risk assessment (QRISK3) performed now would generate a misleadingly high score — deferral is correct practice.
●Management: Treat the thyroid first. Recheck the fasting lipid profile 3–6 months after the patient is confirmed euthyroid (TSH in normal range, symptoms resolved). In most cases, the cholesterol will normalise without a statin. If hyperlipidaemia persists after euthyroidism is achieved, then formal cardiovascular risk assessment and consideration of a statin are appropriate.

Monitoring and Dose Titration

Levothyroxine has a half-life of approximately 7 days. Steady-state serum levels are not reached until 4–6 weeks after a dose change.

●Recheck TSH (and free T4) at 6–8 weeks after initiating or adjusting the dose. Checking earlier gives a misleading result and may prompt premature dose escalation.
●Target TSH: Most patients feel well with a TSH in the lower half of the reference range — NICE CKS recommends aiming for 0.4–2.5 mU/L in most patients on replacement therapy. The target should be individualised if symptoms persist despite a normal TSH.
●Dose titration: Increase in increments of 25–50 mcg every 6–8 weeks until the TSH is within the target range and symptoms have resolved.
●Recheck FBC alongside TFTs at the 6–8 week review to confirm that the macrocytic anaemia is improving. If it fails to resolve with thyroid replacement, reconsider the differential — including early B12 deficiency not yet reflected in serum levels, or an independent haematological cause.
●Recheck the fasting lipid profile 3–6 months after achieving stable euthyroidism, before making any decision about statin therapy.

Safety Netting

●Advise the patient to contact the surgery before the planned follow-up if symptoms significantly worsen, or if she develops chest pain, palpitations, or marked deterioration in mood.
●Palpitations and chest pain in this context would raise the possibility of over-replacement (iatrogenic thyrotoxicosis) — though this is unlikely at initiation doses, it is important to flag.
●Hypothyroidism can cause or worsen depression. If low mood deteriorates beyond what is expected from fatigue, this warrants earlier review.
●Reassure that some improvement in energy may be perceptible within 2–4 weeks, but full benefit typically takes 2–3 months and several dose adjustments.

Menopause as a Diagnostic Distractor

●Hypothyroidism and the perimenopause share multiple symptoms: fatigue, weight gain, mood changes, irregular or heavy periods, cognitive difficulties, and hair changes. This is why Susan attributed her symptoms to menopause for several months — and why this attribution is entirely understandable.
●The blood tests are the diagnostic discriminator. Menopause does not cause a raised TSH, a low fT4, macrocytosis, or significant secondary hypercholesterolaemia. When the clinical picture is ambiguous, thyroid function tests should be checked before attributing symptoms to perimenopause.
●Candidates should acknowledge the menopause attribution explicitly — not to correct the patient, but to validate her reasoning and help her understand why the blood tests changed the picture. This prevents future delays in help-seeking if symptoms recur.

Free MRCGP SCA practice case for GP registrars covering Tiredness, Macrocytic Anaemia, and Hypercholesterolaemia — Haematology. Includes candidate brief, patient script, marking scheme mapped to the RCGP SCA marking domains, and learning points. Built directly from the RCGP curriculum topic stations listed under "How this might be tested in the MRCGP SCA," part of a free library of 79 SCA practice cases for simulated consultation assessment preparation.

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