Practice questions answers II Pathology of endocrine pancreas
Practice questions answers
Pathology of endocrine pancreas II
© Jun Wang, MD, PhD
1. E. Dizziness and sweating are
commonly seen in patient with hypoglycemia,
the most common acute complication in patient with diabetes.
It can be confirmed with abnormally low blood glucose. Diabetic
ketoacidosis has lower arterial pH and elevated ketone in urine, as
well as hyperglycemia. Diabetic
nephropathy has proteinuria and is more likely a chronic process
without sudden onset of neurological symptoms, and does not cause hypoglycemia.
Diabetic
neuropathy is a chronic process involving both motor and sensory functions,
but does not cause hypoglycemia.
Hyperosmolar
hyperosmotic syndrome has a blood glucose > 600 mg/dl.
2. D. The most common causes of hypoglycemia
in patients with diabetes
include skipping meals, excessive exercise, excess insulin administration, etc.
Excess fatty acid metabolism is seen in diabetic
ketoacidosis. Glucagonoma
causes hyperglycemia, not hypoglycemia.
Insulinoma
may cause hypoglycemia, but not elevated HbA1c. Osmotic diuresis is seen in hyperosmolar
hyperosmotic syndrome with a blood glucose > 600 mg/dl.
3. D. Macrovascular complications are the
most common cause of mortality in patients with long standing diabetes.
The pathogenesis include consequences of advance glycation end products and associated
vascular inflammation and smooth muscle proliferation, alteration of
extracellular matrix, PKC activation, oxidative stress and disturbance of
polyol pathways. Smooth muscle proliferation, although is common in
atherosclerosis caused by other disorders, is largely accelerated in patients
with diabetes
through advanced glycation end products. Atherosclerosis associated with endothelial
injury caused by hypertension are more commonly seen in larger arteries. In
patients with diabetes,
the production of intracellular fructose is indeed increased. The
ulcers/gangrenes in patients with diabetes
are usually ischemic, due to atherosclerosis, not infection.
4. B. Diabetic
nephropathy is a common complication of diabetes,
especially in those with early onset of microalbuminuria. It is the leading
cause of end stage renal disease. Diabetic
ketoacidosis is a major life-threatening complication, but it is
more commonly associated with type
I diabetes. Hypoglycemia
is the most common acute complication in
patient with diabetes.
Both are much less common than diabetic
nephropathy. Lung cancer and sepsis are not major concerns of diabetes.
5. B. See discussion in question 4.
6. C. Sole proteinuria in a patient with
diabetes
is most consistent with diabetic
nephropathy, commonly with diffuse and nodular glomerulosclerosis,
diffuse mesangial sclerosis, diffuse capillary basement membrane thickening, or
pyelonephritic type changes, such as tubular atrophy, interstitial fibrosis and
inflammation. Benign cyst formation, interstitial fibrosis and interstitial
inflammation can be seen in autosomal
dominant (adult) polycystic kidney disease. Diffuse neutrophilic and
lymphocytic infiltration is more likely associated with pyelonephritis.
Epithelial proliferation of Bowman’s capsule with crescent formation is seen in
rapidly progressive glomerulonephritis. Smooth muscle presentation may be seen
in atherosclerosis, but is less common
in diabetic
nephropathy.
7. E. Diabetic
nephropathy is associated with increased glomerular extracellular
matrix, resulted from hyperglycemia. Autoimmune glomerular injury is usually associated
with nephritis, characterized by hematuria. Epithelial proliferation of Bowman’s
capsule with crescent formation is seen in rapidly progressive
glomerulonephritis.
8. B. Sole proteinuria in a patient with
diabetes
is most consistent with diabetic
nephropathy. Most nephritis usually has hematuria. End stage renal
disease has elevated BUN and creatinine. Membranous glomerulonephritis has
nephrotic syndrome, characterized by marked proteinuria, hyperlipidemia, edema
and hypoalbuminemia.
9. B. Diabetic
nephropathy is the leading cause of end stage renal disease.
Impaired renal function is usually associated with hypocalcemia and secondary
hyperparathyroidism. Severe osteoporosis is more commonly associated with primary
hyperparathyroidism, not end stage renal disease.
10. C. Progressive blurring vision in a
patient with diabetes,
without optic disc and lens abnormalities are most suggestive of diabetic
retinopathy, especially with the presence of cotton
wool spots. Cataract is lens abnormality. Diabetic optic neuropathy usually
has edematous changes of the optic disc. Glaucoma has elevated intraocular
pressure. Thyroid
oculopathy is characterized by changes outside the eyes, not retina.
11. A. Recurrent hypoglycemia associated
with increase insulin production (suggested by high insulin and C-peptide) is
suggestive of insulinoma
of pancreas. Drug effects, brain disorders and arrhythmia associated syncope
usually do not have increase insulin production. Glucose tolerance test is for diabetes.
12. B. See discussion in question 11.
13. B. Benign appearing pancreas
epithelial tumor in the background of elevated insulin production is most
likely insulinoma.
Glucagonoma
is commonly associated with hyperglycemia, not hypoglycemia. Pancreas
adenocarcinoma with solid cords are high grade tumor, and usually have marked
cytological atypia. Plasmacytoma
and small
lymphocytic lymphoma are negative for cytokeratin.
14. D. Pancreas tumor in a patient with
presentations of diabetes
and necrolytic
migratory erythema is highly suggestive of Glucagonoma.
Elevated C peptide and insulin are usually associated with hypoglycemia, insulinoma,
or early stage type
II diabetes. CA19.9 is associated with biliary/pancreas
adenocarcinoma and mucinous
cystadenocarcinoma of ovary. Elevated gastrin is seen in Zollinger-Ellison
Syndrome, characterized by multiple gastric or duodenal benign ulcers.
15. A. See discussion in question 14.
16. E. See discussion in question 14.
Peptic ulcers are commonly associated with helicobacter infections.
17. E. Patient with pancreas tumor and
clinical presentation of WDHA syndrome (Watery Diarrhea, Hypokalemia,
Achlorhydria) is likely to have VIPoma,
a tumor producing vasoactive intestinal polypeptide. It should be suspected in
patients with unexplained high-volume secretory diarrhea. Also see discussion
in question 14.
18. D. See discussion in questions 14
and 17. Chronic gastroenteritis usually does not have markedly elevated vasoactive
intestinal polypeptide.
Back to pathology
of endocrine pancreas
Back to pathology
of endocrine system
Back to contents
Comments
Post a Comment