Hypoglycemia Interpretation

Question 1

What condition is characterized by excessive insulin levels?

Answer 1

Hyperinsulinemia

This can be due to insulinoma, exogenous insulin, or sulfonylurea use.

Question 2

What is the plasma insulin concentration indicative of insulin excess?

Answer 2

≥23.0 plU/mL (≥20.8 pmol/L) with plasma glucose <55 mg/dL (<3.1 mmol/L)

This indicates hyperinsulinemia.

Question 3

What is the significance of measuring C-Peptide levels in diagnosing insulinoma?

Answer 3

C-Peptide levels help differentiate between endogenous and exogenous insulin sources.

Low C-Peptide levels suggest exogenous insulin.

Question 4

What are the C-Peptide level thresholds for diagnosing hyperinsulinemia?

Answer 4

≥0.6 ng/mL (≥0.20 nmol/L) indicates insulin excess; <0.6 ng/mL (<0.20 nmol/L) suggests exogenous insulin.

These levels help in confirming the source of insulin.

Question 5

What is the threshold for Proinsulin levels in diagnosing insulinoma?

Answer 5

≥44 pg/mL (≥5.0 pmol/L)

Normal or low levels are <44 pg/mL (<5 pmol/L).

Question 6

What does a 3-Hydroxybutyrate level of >2.7 mmol/L indicate?

Answer 6

Indicates insulinoma or sulfonylurea use.

Abdominal CT can be used for localization after ruling out sulfonylurea.

Question 7

What is the recommended screening for patients with suspected insulinoma?

Answer 7

Supervised fast and plasma insulin testing

This helps to confirm the diagnosis effectively.

Question 8

What is the role of the Cosyntropin-stimulation test in diagnosing insulinoma?

Answer 8

No role

It’s unnecessary in the context of hypoglycemia evaluation.

Question 9

What is the plasma insulin concentration indicative of sulfonylurea use?

Answer 9

≥23.0 ulU/mL (≥20.8 pmol/L)

This can overlap with insulinoma diagnosis.

Question 10

What is the guideline regarding the measurement of IGF-2 in insulinoma diagnosis?

Answer 10

Measurement of IGF-2 is not required

It is unnecessary if all necessary laboratory tests for hypoglycemia are already documented.

Question 11

Fill in the blank: Plasma insulin concentration indicating insulin excess is _______.

Answer 11

≥23.0 plU/mL (≥20.8 pmol/L) with plasma glucose <55 mg/dL (<3.1 mmol/L)

This indicates hyperinsulinemia.

Question 12

True or False: Proinsulin levels below 44 pg/mL are normal.

Answer 12

True

Normal or low Proinsulin levels are <44 pg/mL (<5 pmol/L).

Question 13

صورة المصدر

Answer 13

Question 14

What is the significance of suppressed B-hydroxybutyrate and increased glucose after glucagon in a patient?

Answer 14

Indicates a potential issue with glucose metabolism or hormone regulation

This observation can suggest an abnormal response to glucagon, possibly linked to hypoglycemia.

Question 15

What levels are noted in a patient with suspected hypoglycemia related to IGF-2?

Answer 15

Low insulin and C-peptide levels

These findings can help differentiate between endogenous and exogenous causes of hypoglycemia.

Question 16

What weight change is noted in patients with hypoglycemia related to IGF-2?

Answer 16

Weight loss noted

Weight loss can be a significant symptom in cases of malignancy or hormone imbalances.

Question 17

What is a possible diagnosis for a patient with excess circulating IGF-2?

Answer 17

Possible tumor producing excess circulating IGF-2

This condition may arise from an undiagnosed malignancy.

Question 18

What imaging technique is used to confirm the diagnosis of a tumor related to IGF-2?

Answer 18

Whole-body imaging

This is crucial for locating the tumor responsible for excess IGF-2 production.

Question 19

What ratio is measured to confirm tumor secretion of IGF-2?

Answer 19

IGF-2 to IGF-1 ratio

A ratio greater than 3 indicates tumor secretion of IGF-2.

Question 20

True or False: An IGF-2 to IGF-1 ratio of >3 indicates tumor secretion of IGF-2.

Answer 20

True

This finding is critical in diagnosing conditions related to IGF-2.

Question 21

What condition may cause impaired glucagon response due to low glucose stores?

Answer 21

Adrenal Insufficiency

This condition can complicate the picture of hypoglycemia.

Question 22

What is a characteristic finding in factitious insulin administration?

Answer 22

C-peptide usually undetectable

This finding helps to differentiate factitious causes from endogenous insulin production.

Question 23

What weight change is unexpected in cases of factitious insulin administration?

Answer 23

Weight loss not expected

Patients typically do not lose weight in factitious insulin cases, unlike those with malignancies.