INI-CET 2022 — Physiology

Q: Which of the following represents a normal response to an OGTT?

Graph D. ***Graph D*** - Graph D shows a **fasting glucose level** below 100 mg/dL, a peak below the renal threshold around 1 hour, and a return to baseline or below within 2-2.5 hours. This pattern is characteristic of normal glucose regulation. - A healthy individual can efficiently clear the glucose load from circulation, preventing sustained hyperglycemia. *Graph A* - Graph A shows significantly **elevated fasting glucose levels** (above 200 mg/dL) and a sustained, very high blood glucose response, peaking above 350 mg/dL and remaining well above the renal threshold. - This pattern is indicative of **diabetes mellitus**, where insulin production or sensitivity is severely impaired. *Graph B* - Graph B displays a high fasting glucose level (above 125 mg/dL) and a blood glucose curve that peaks very high (above 250 mg/dL), staying significantly above the renal threshold even at 2.5 hours. - This profile is suggestive of **impaired glucose tolerance** or **diabetes mellitus**, as the body struggles to effectively lower blood glucose after the glucose load. *Graph C* - Graph C shows a normal fasting glucose level but an **extremely rapid and high peak** much earlier than usual, followed by a precipitous drop below normal fasting levels after 1.5 hours, indicating **reactive hypoglycemia**. - This rapid rise and fall, with a nadir below fasting levels, is not a normal response and may be seen in conditions like **dumping syndrome** or early-stage diabetes with a delayed insulin response.

11 Questions — Page 2 of 2

Q11

Which of the following represents a normal response to an OGTT?