Diabetes Mellitus and Acute Metabolic Emergencies — WACS Viva & Clinical Scenarios (Endocrinology, Diabetes, and Metabolism)

Exam-style diabetes mellitus and acute metabolic emergencies viva scenarios with examiner probes and model answers for Internal Medicine candidates.

Scenarios covered

• SCENARIO 1: A 24-year-old female with known Type 1 diabetes presents to the emergency department with a 2-day history of persistent vomiting, generalized abdominal pain, deep rapid breathing, and progressive lethargy following an untreated urinary tract infection. On examination, she is dehydrated, blood pressure is 95/60 mmHg, heart rate is 118 beats per minute, respiratory rate is 32 breaths per minute (Kussmaul breathing), and Glasgow Coma Scale is 13/15. Point-of-care capillary glucose is 26.4 mmol/L, capillary blood ketones are 4.8 mmol/L, arterial blood gas shows pH 7.12, serum bicarbonate 9 mmol/L,
• SCENARIO 2: A 68-year-old male with poorly controlled Type 2 diabetes is brought to the medical ward with acute confusion, extreme lethargy, and profound dehydration following a 1-week history of low-grade fever and productive cough. Laboratory analysis reveals a random plasma glucose of 42.0 mmol/L, serum sodium of 152 mmol/L, serum potassium of 4.8 mmol/L, blood urea of 21.4 mmol/L, serum creatinine of 188 µmol/L, arterial blood gas pH of 7.36, serum bicarbonate of 20 mmol/L, and trace urinary ketones. Detail the diagnostic calculation of effective serum osmolality, initial fluid selection and replaceme
• SCENARIO 3: A 58-year-old male with a 12-year history of Type 2 diabetes presents with an infected, non-healing ulcer over the plantar aspect of the first metatarsal head of the right foot. You are required to perform a comprehensive neurovascular and local foot examination, classify the lesion using the University of Texas or Wagner staging system, formulate an investigation plan to evaluate underlying osteomyelitis and peripheral arterial disease, and design a multi-disciplinary limb-salvage strategy including wound bed debridement, offloading, and empirical antibiotic therapy.
• SCENARIO 4: A 45-year-old male presents with recurrent episodes of diaphoresis, palpitations, tremors, and cognitive dysfunction occurring primarily during early morning fasting, which are rapidly relieved by carbohydrate intake. Outline the components of the Whipple triad, differential diagnosis of fasting versus postprandial hypoglycaemia in non-diabetic individuals, the 72-hour prolonged fast protocol, interpretation of paired serum insulin, C-peptide, and beta-hydroxybutyrate measurements, and the emergency pharmacological protocol for severe neuroglycopenic collapse.
• SCENARIO 5: A 62-year-old female with a 9-year history of Type 2 diabetes, established ischaemic heart disease, and stage 3b chronic kidney disease (estimated glomerular filtration rate 38 mL/min/1.73 m², urine albumin-to-creatinine ratio 32 mg/mmol) has an HbA1c of 8.9% despite taking maximum tolerated doses of metformin. Discuss the pharmacological selection, mechanisms of action, renal dosage thresholds, cardiovascular outcome benefits, and safety profiles of sodium-glucose co-transporter-2 (SGLT-2) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists, dipeptidyl peptidase-4 (DPP-4) inhibitors