Clinical Assessment and Diagnosis
What the exam expects
Clinical assessment in advanced diabetes practice blends diagnostic criteria with pattern recognition. Know the accepted glycemic diagnostic thresholds and the requirement for confirmation when a result is asymptomatic. Distinguish screening from diagnosis, and know which tests are valid in special populations (pregnancy, anemia, hemoglobinopathies, recent transfusion, chronic kidney disease). Understand that A1C reflects roughly three months of glycemia but is influenced by red cell turnover.
Concepts to master
- Fasting plasma glucose, 2-hour oral glucose tolerance test, random glucose with classic symptoms, and A1C as diagnostic pathways.
- Prediabetes categories and the rationale for annual rescreening.
- Differentiating type 1, type 2, and atypical diabetes (LADA, ketosis-prone, secondary to pancreatitis or steroids).
- History elements: polyuria, weight change, hypoglycemia pattern, medication adherence, sleep, mood, social determinants.
- Physical exam: foot inspection, injection sites, acanthosis nigricans, blood pressure, and retinal screening status.
Traps
Questions often present an asymptomatic patient with one abnormal value and ask for the next step; the answer is repeat testing, not immediate pharmacotherapy. Another trap is trusting A1C in a patient with sickle cell trait or recent blood loss. Watch for "normal A1C excludes diabetes" wording in someone with symptoms and a high random glucose.
Rule of thumb
If the patient has classic hyperglycemic symptoms plus a random glucose clearly in the diabetic range, the diagnosis is established; otherwise confirm with a second abnormal test on a separate day.
Worked example
A 46-year-old with obesity has a fasting glucose of 128 mg/dL and no symptoms. This is abnormal but not yet diagnostic alone; repeat testing (fasting glucose, A1C, or OGTT) confirms. If the repeat A1C is 6.6%, type 2 diabetes is diagnosed and management begins.