1.25: The Pancreas- Function and Chemical Pathology
- Page ID
- 38605
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- All of the following hormones are produced primarily in pancreatic islets EXCEPT:
- Gastrin
- Glucagon
- Insulin
- Pancreatic polypeptide
- Somatostatin
- Which of the following statements concerning islet cell function is correct?
- Insulin is the initial protein product of pancreatic beta cells
- Insulin is co-secreted with glucagon
- Insulin and C-peptide are produced in equimolar amounts
- Alpha cells are the major source of somatostatin in the pancreas
- Delta cells produce pancreatic polypeptide and vasoactive intestinal peptide
- All of the following enzymes are produced in their active forms by the pancreas EXCEPT:
- Amylase
- Cholesterol esterase
- Lipase
- Ribonuclease
- Trypsin
- Which of the following statements concerning pancreatic exocrine function is correct?
- Amylase is activated in the duodenum by the action of gastric acid and trypsin
- Exocrine secretion produces 8-10 liters of pancreatic juice daily
- Gastric acid is critical in inactivation of pancreatic enzymes
- Pancreatic bicarbonate production is critical to the digestive process
- The amount of amylase and lipase in pancreatic secretions is about 100 times plasma levels
- Which of the following statements concerning hypoglycemia and insulinoma is correct?
- Hypoglycemia is most commonly due to insulinoma.
- Insulinoma is typically a highly aggressive tumor, with early metastasis to the liver and lungs.
- Insulinoma can be distinguished from sulfonylurea ingestion because C-peptide is increased only in the former
- Insulin injection is not associated with elevated C-peptide.
- Ratio of insulin to glucose > 20 suggests that excess insulin is the cause of hypoglycemia.
- Which of the following statements concerning islet cell tumors is INCORRECT?
- Gastrin production in excess (Zollinger-Ellison syndrome) is usually caused by an islet cell
tumor of the pancreas - Glucagonoma usually presents with hyperglycemia, weight loss, and skin rash
- PPomas usually present with watery diarrhea and weight loss
- Somatostatinomas are usually large, malingant tumors with minimal or non-specific syndromes
- VIPomas are associated with watery diarrhea, hypokalemia, and achlorhydria
- Gastrin production in excess (Zollinger-Ellison syndrome) is usually caused by an islet cell
- The most efficient marker for the diagnosis of acute pancreatitis is
- Amylase in serum
- Amylase in urine
- Lipase
- Pancreatic amylase isoenzyme
- Trypsinogen (immunoreactive trypsin)
- Which of the following statements concerning tests of acute pancreatic injury is correct?
- Amylase and lipase are highly specific for pancreatitis, but not very sensitive
- Elevation of both amylase and lipase to more than 5 times upper reference limits with rise and fall over 48 hours is highly suggestive of pancreatitis
- Lipase will generally return to normal earlier than amylase because of its shorter half-life
- Renal insufficiency is associated with reductions in both amylase and lipase
- With optimized lipase assays, lipase activity is typically about 1/4th that of amylase
- Factors associated with a poor prognosis in acute pancreatitis include all of the following EXCEPT:
- Amylase over 10 times the upper reference limit
- Calcium decrease to less than 80 mg/L (2 mmol/L) over the first 48 hours
- Glucose over 2000 mg/dL at the time of admission
- Hematocrit decrease over 10% over the first 48 hours
- Partial pressure of oxygen < 50 mm Hg over the first 48 hours
- Causes of increased salivary amylase include all of the following EXCEPT:
- Coronary artery bypass surgery
- Diabetic ketoacidosis
- Ectopic pregnancy
- Intestinal ischemia
- Mumps
- The most sensitive test of pancreatic insufficiency is
- Amylase
- Bicarbonate level in duodenal fluid after secretin administration (secretin test)
- Fecal fat excretion
- Immunoreactive trypsin in serum
- Trypsin catalytic activity in stool
- Answer
-
- a (p. 539)
- c (p. 538)
- e (p. 540)
- d (p. 539)
- d (p. 541)
- c (p. 541-542)
- e (p. 543)
- b (p. 543)
- a (p. 544)
- d (p. 544-545)
- b (p. 546)