PUID: 42 || Vitamin D Deficiency in PLAB 2: Diagnosis, Safety Netting, and Effective Consultation, a PLAB 2 Mock- Attempt 1

Practice a case with the AI patient 🤖

Summary:

This scenario involves a patient presenting with tiredness and constipation, with investigations revealing vitamin D deficiency and mild hypocalcemia. The station tests your ability to integrate clinical reasoning, safety netting, and structured data gathering without prematurely fixating on results.

Key Points:

Presenting Complaint: Tiredness and Constipation

• Always start data gathering with presenting symptoms before discussing results.

• Explore tiredness systematically: thyroid, anemia, malignancy, depression, sleep hygiene, chronic diseases.

• For constipation, consider red flags:

  • Alternating bowel habits (e.g. constipation with intermittent diarrhea suggests colorectal pathology).

  • Weight loss.

  • Blood in stool or change in stool calibre.

Investigations Interpretation

• Avoid tunnelling based on results alone; gather full history to guide interpretation.

• Vitamin D deficiency and hypocalcemia often co-exist due to impaired calcium absorption.

• Relevant investigations:

  • Vitamin D (25-OH) levels

  • Calcium levels

  • Renal function tests (for vitamin D activation)

  • Consider malabsorption causes (e.g. coeliac disease, IBD).

Vitamin D Metabolism

• Synthesised in skin (7-hydroxycholesterol → D3) under UV light.

• Activated via:

  • Liver (25-hydroxylation → 25-OH Vitamin D)

  • Kidney (1-alpha hydroxylation → active calcitriol)

• Facilitates calcium absorption in gut and reabsorption in kidneys; deficiency leads to hypocalcemia and poor bone mineralisation.

Important Considerations:

• Always assess sunlight exposure and dietary intake.

• Consider malabsorption as a cause of deficiency (e.g. GI pathology).

• Hypocalcemia requires vitamin D correction before calcium replacement for effective management.

• In the UK, vitamin D deficiency is common due to limited sun exposure; supplements are often required.

• Do not force-fit a diagnosis if unsure; admit limitations and escalate to seniors appropriately.

Diagnostic Approach:

1. Data Gathering

   • Explore tiredness comprehensively.

   • Assess constipation: bowel habits, red flags.

   • Review dietary intake, sun exposure, GI symptoms.

2. Interpret Results

   • Correlate history with results systematically.

   • Confirm vitamin D deficiency and assess calcium impact.

3. Differential Diagnosis

   • Hypocalcemia secondary to vitamin D deficiency.

   • Malabsorption syndromes.

   • Less likely: Hypoparathyroidism, renal disease (if relevant results normal).

Management:

Immediate:

• Explain results in simple terms, ensuring patient understanding.

• Safety net: advise to seek urgent care if symptoms worsen (e.g. chest pain, severe dizziness).

• Provide patient leaflets on tiredness and vitamin D deficiency.

Definitive:

• Prescribe vitamin D supplementation as per UK guidelines (loading dose if deficient, then maintenance).

• Dietary advice: vitamin D-rich foods.

• Discuss calcium supplementation if symptomatic hypocalcemia persists after vitamin D repletion.

• Set a follow-up appointment to monitor symptom improvement and biochemical correction.

Communication Skills:

• Start consultation by confirming reason for visit before diving into results.

• Avoid medical jargon; explain results clearly.

• Safety net effectively by explaining red flag symptoms requiring urgent review.

• Use NHS-appropriate methods: leaflets, follow-up, escalation when needed.

• Avoid stock phrases and demonstrate genuine, structured empathy.

Ethical Considerations:

• Recognise competence limitations; involve seniors when unsure (maintains patient safety).

• Maintain honest, transparent communication with patients regarding diagnosis and management.

• Uphold Good Medical Practice standards by providing care within your competence and ensuring patient-centred consultations.

Additional Resources:

• NICE Guidelines on vitamin D deficiency management

• GMC Good Medical Practice (2024) for communication and safety netting standards

• BMJ Best Practice: Hypocalcemia and Vitamin D deficiency