BC ADM Comprehensive Diabetes Assessment & Diagnosis 3 — Questions and Answers
Question 1: A 34-year-old non-obese woman of South Asian descent is diagnosed with diabetes. GCK mutation is identified on genetic testing. Which subtype does she have?
- Type 2 diabetes
- MODY 2 (GCK-MODY) (Correct answer)
- LADA (latent autoimmune diabetes in adults)
- Type 1 diabetes
Correct answer: MODY 2 (GCK-MODY)
GCK-MODY (MODY 2) is caused by heterozygous glucokinase mutations that raise the glucose set-point, causing mild stable hyperglycemia that rarely requires pharmacotherapy.
Question 2: Which symptom is most characteristic of hyperosmolar hyperglycemic state (HHS) at presentation compared to diabetic ketoacidosis?
- Deep Kussmaul respirations
- Profound dehydration with minimal to no ketosis (Correct answer)
- Rapid-onset acidosis
- Serum bicarbonate < 15 mEq/L
Correct answer: Profound dehydration with minimal to no ketosis
HHS is characterized by extreme hyperglycemia (often >600 mg/dL), severe dehydration, and hyperosmolality without significant ketoacidosis.
Question 3: Which HbA1c value meets the ADA diagnostic threshold for diabetes in the absence of hyperglycemic symptoms?
- ≥5.7%
- ≥6.0%
- ≥6.5% (Correct answer)
- ≥7.0%
Correct answer: ≥6.5%
HbA1c ≥6.5% on two separate tests (or once with confirmatory testing) meets ADA criteria for diagnosing diabetes.
Question 4: A patient reports episodes of sweating, tremor, and confusion 3 hours after meals. Post-prandial glucose at 3 hours is 48 mg/dL. What condition should be evaluated?
- Dawn phenomenon
- Reactive hypoglycemia / postprandial hypoglycemia (Correct answer)
- Somogyi effect
- Diabetic autonomic gastroparesis
Correct answer: Reactive hypoglycemia / postprandial hypoglycemia
Reactive hypoglycemia presents with adrenergic and neuroglycopenic symptoms 2–5 hours after a meal, confirmed by low glucose during symptoms.
Question 5: Which laboratory finding distinguishes latent autoimmune diabetes in adults (LADA) from classic type 2 diabetes?
- Age of onset > 40 years
- Presence of GAD65 autoantibodies with low C-peptide (Correct answer)
- BMI > 30 kg/m²
- Response to metformin therapy
Correct answer: Presence of GAD65 autoantibodies with low C-peptide
Positive GAD65 autoantibodies combined with declining C-peptide distinguishes LADA from type 2 diabetes and signals eventual insulin dependence.
Question 6: In assessing diabetes management quality, time-in-range (TIR) refers to the percentage of CGM readings between which glucose values?
- 54–180 mg/dL
- 70–180 mg/dL (Correct answer)
- 80–140 mg/dL
- 70–200 mg/dL
Correct answer: 70–180 mg/dL
International consensus defines TIR as the percentage of time glucose remains within 70–180 mg/dL for most non-pregnant adults with diabetes.
Question 7: A 55-year-old man with type 2 diabetes has an eGFR of 38 mL/min/1.73m². Which drug class requires dose adjustment or discontinuation at this level?
- GLP-1 receptor agonists
- Metformin (Correct answer)
- DPP-4 inhibitors
- Thiazolidinediones
Correct answer: Metformin
Metformin is contraindicated when eGFR falls below 30 and should be used cautiously with dose adjustment when eGFR is 30–45 due to lactic acidosis risk.
BC ADM Comprehensive Diabetes Assessment & Diagnosis 3
A 34-year-old non-obese woman of South Asian descent is diagnosed with diabetes.
GCK mutation is identified on genetic testing.
Which subtype does she have?