Diabetes Mellitus — Written Clinical Reasoning

SAQ 1 — Integrated Management (20 marks, 30 minutes)

Prompt: Outline your integrated management plan for this patient, addressing glycaemic control, cardiovascular risk reduction, nephropathy, neuropathy, retinopathy, and the diabetic foot ulcer. Justify each pharmacological decision with reference to evidence. ^[1]

Model Answer

Problem list (4 marks):

1. Type 2 diabetes with suboptimal glycaemic control (HbA1c 71 mmol/mol) on two oral agents
2. Diabetic nephropathy — stage 3B CKD (eGFR 42) with albuminuria (ACR 18 mg/mmol)
3. Ischaemic heart disease (NSTEMI 2 years ago, DES to RCA) — established ASCVD
4. Diabetic peripheral neuropathy with loss of protective sensation
5. Diabetic foot ulcer — neuropathic plantar ulcer under right first metatarsal head
6. Background diabetic retinopathy (microaneurysms, dot-blot haemorrhages)
7. Hypertension (148/86) — above target for a proteinuric diabetic patient
8. Obesity (BMI 33)
9. Occupation — commercial driver (hypoglycaemia and visual acuity implications) ^[1]

Glycaemic and pharmacological management (8 marks): ^[1]

This patient has established atherosclerotic cardiovascular disease (prior NSTEMI), diabetic nephropathy with albuminuria, and obesity — three factors that mandate an organ-protective agent, not just a glucose-lowering agent. The modern hierarchy: ^[1]

Target HbA1c: 53 to 58 mmol/mol (7.0 to 7.5%). He has established ASCVD and CKD but is relatively young (64) and active — a moderate target. Avoid aggressive targets below 48 given his occupation (hypoglycaemia while driving is catastrophic) and the ACCORD harm signal in patients with established cardiovascular disease. ^[1]

Cardiovascular risk reduction (3 marks):

• Blood pressure: target below 130/80 (albuminuric diabetic). Start ramipril 2.5mg daily (or any ACE inhibitor) — renoprotective in albuminuria, independent of blood pressure. Monitor creatinine and potassium at 1 to 2 weeks (accept rise up to 30%). Do not combine ACEi and ARB (ONTARGET harm).
• Lipids: already on atorvastatin 40mg — consider intensifying to 80mg (high-intensity statin for secondary prevention). All diabetics with established ASCVD should be on high-intensity statin.
• Antiplatelet: he should be on aspirin 100mg daily for secondary prevention (post-NSTEMI). Confirm adherence. Clopidogrel if aspirin-intolerant.
• Lifestyle: weight loss (GLP-1 RA will help), Mediterranean diet, 150 min/week exercise, smoking status (confirm). ^[1]

Nephropathy (2 marks):

• ACE inhibitor (ramipril) — reduces intraglomerular pressure and albuminuria.
• SGLT2 inhibitor (dapagliflozin) — DAPA-CKD showed 39% reduction in renal composite.
• Monitor eGFR and urine ACR every 3 to 6 months. Refer to nephrology if eGFR falls below 30 or rapid decline.
• Blood pressure target below 130/80. ^[1]

Diabetic foot ulcer (2 marks):

• This is a neuropathic plantar ulcer (palpable pulses implied by the scenario; loss of protective sensation; callus; no surrounding erythema suggesting no active infection).
• Offloading: total contact cast is the gold standard for plantar neuropathic ulcers.
• Debridement: sharp debridement of surrounding callus by a podiatrist or foot clinic.
• Wound care: appropriate dressing; monitor for infection.
• Multidisciplinary foot clinic referral — mandatory.
• Assess for ischaemia: ankle-brachial index (may be falsely elevated due to medial calcinosis — use toe pressures if abnormal), palpate pulses.
• Probe-to-bone test — if bone is reached, osteomyelitis is likely; confirm with MRI. ^[1]

Retinopathy and neuropathy (1 mark):

• Retinopathy: refer to ophthalmology for formal assessment. Background retinopathy — annual surveillance. Note: rapid glycaemic improvement can worsen retinopathy early — screen closely during therapy escalation.
• Neuropathy: loss of protective sensation confirmed — foot education, daily foot inspection, appropriate footwear (offloading insoles). Screen for autonomic neuropathy (orthostatic hypotension, erectile dysfunction, gastroparesis symptoms). ^[1]