Endocrinology Flashcards
Basal rate of insulin changes throughout the day. When is it highest?
Pre-dawn hours
Insulin pumps use which type of insulin?
Rapid acting insulin (Lispro)
CSII is recommended by the AACE for patients:
treated with insulin for T2DM
The pump reservoir holds how many days worth of insulin? Where is the insulin delivered?
2 - 3 days. Subcutaneous tissue.
Where are the infusion set sites?
Abdomen, arm, thighs, hip/buttocks
When might a patient need to program an insulin pump to DECREASE basal rate delivery?
Before exercise
When might a patient need to program an insulin pump to INCREASE basal rate delivery?
During illness, infection, on steroids
What factors are necessary to calculate bolus for an insulin pump? Meal bolus? Correction bolus?
Meal bolus: insulin-to-carb ratio, carbs in meal, activity level
Correction: Insulin sensitivity factor, blood glucose target, pre-meal blood glucose, active insulin
CGM device should be worn for how long?
3 days at least (in lecture said 7 days is best to get an idea of patient’s behavior/patterns)
For which patients is CGM recommended?
Elevated A1c (>6.5-7%) in pts with diabetes on insulin therapy
If better understanding of postprandial and overnight glucose is needed
Pregnancy
A1c levels inconsistent with meter logs
For a patient receiving CSII, what should peak blood glucose values be for postprandial period (3 hours after food intake)?
Less than 135 - 180 mg/dL
What can the MiniMed Paradigm device do for a patient?
It is an insulin pump plus CGM that can alert patient when thresholds for blood glucose are reached
With combined CGM and CSII, finger sticks are needed for?
Therapy modification
Calibration
BMI =
weight (kg)/height (m)2
Above which BMI does the risk for comorbidities begin to rise?
Above 25
Waist to hip ratio for men and women?
Women > 0.9, men > 1.0
Hormone that is an important regulator of appetite, energy expenditure, and neuroendocrine fx in the hypothalamus?
Leptin
GLP-1 is produced in the gut and has what effect?
Decreased food intake
What is the stratification of energy expenditure?
Basal rate uses about 70%
Physical activity uses 5 - 10%
Genetic syndromes related to some cases of obesity:
Decreased leptin production Increased leptin resistance Cushing's syndrome Hypothyroidism Insulinoma >> overeating Craniopharyngioma and other hypothalamic disorders
How does obesity affect the reproductive axis for males?
Hypogonadism, increased adipose tissue with pattern of distribution more commonly seen in women
How does obesity affect the reproductive axis in females?
Menstrual abnormalities, esp with upper body obesity
What are the molecular markers of increased risk for cancer in obesity?
Increased insulin, Leptin, adiponectin, and IGF-1
Obesity class for patient with BMI of 30.0 - 34.9
Class I: high risk of disease
Obesity class for patient with BMI of 35.0 - 39.9
Class II: very high risk of disease
Obesity class for patient with BMI > or = to 40
Class III: extremely high risk of disease
A patient with a BMI of 25.0 - 29.9 is
overweight
A patient with a BMI
Underweight
How many calories in a very low calorie diet?
How much exercise is recommended?
150min/wk moderate intensity
What obese patients are candidates for pharmacotherapy?
BMI > 30
BMI > 27 with morbid conditions
Obesity drug that stimulates norepinephrine release or blocks its uptake:
Phentermine
Obesity drug that functions as a serotonin and norepinephrine reuptake inhibitor that is not on market anymore:
Sibutramine (Meridia)
Obesity drug that is an NE reuptake inhibitor and opioid receptor antagonist.
Has dopamine effect, decreases pleasure derivation from food.
Contrave (buproprion; naltrexone)
Obesity drug that is a 5-HT2C receptor agonist
Lorasecin
Qsymia is a combination of which two drugs?
Phentermine and topiramate
Obesity drug that is a GLP-1 analogue, given byy injection.
-Weight loss, decreased oral intake, decreased gastric emptying. Nausea.
Saxenda (Liraglutide)
When is surgery indicated for an obese patient?
BMI > 40
BMI > 35 with medical comorbidities
Which surgery to correct obesity involves cutting out part of stomach or putting band around stomach to decrease volume?
Restrictive:
-Sleeve gastrectomy
Which surgery to correct obesity involves removing part of the stomach or placing a band AND a part of the small intestine is removed?
Restrictive-malabsorptive:
-Roux-en-Y gastric bypass (RYGB) MC bypass
-Biliopancreatic diversion (BPD)
Biliopancreatic diversion with duodenal switch (BPDDS)
Multiple Endocrine Neoplasia syndrome that is:
Autosomal dominant
Occurs in 1 in 30,000
Covers the “3 P’s”
MEN 1 or Wermer’s syndrome
What are the three P’s of Wermer’s syndrome?
Pituitary adenoma
Parathyroid hyperplasia
Pancreatic tumor
What is the MC feature of MEN 1?
Hyperparathyroidism
The P of MEN 1 that occurs in 25% of patients, is rarely malignant, and can be functional or nonfunctional:
Pituitary adenoma
What hormone stimulates calcium reabsorption in the distal tubule and inhibits phosphorus reabsorption in proximal and distal tubules?
Parathyroid hormone
In MEN 1, parathyroid hyperplasia usually involves how many glands?
All four
What might distinguish MEN 1 hyperparathyroidism from sporadic hyperPTH?
MEN 1 hyper PTH occurs about 2 decades sooner (2nd - 4th decade)
What are the different neuroendocrine tumors that could form in the pancreas with MEN1 (5)?
Gastrinoma Insulinoma Glucagonoma VIPoma Somatostatinoma
Of the pancreatic neuroendocrine tumor types, which is the most common? What resultant syndrome is it associated with?
Gastrinoma (40 - 60%); associated with Zollinger-Ellison syndrome.
How is a gastrinoma diagnosed?
Secretin stimulation test: gastrin will be secreted in a gastrinoma in response to secretin but not in normal tissue
What is the second MC pancreatic neuroendocrine tumor in MEN1? How often are they malignant?
Insulinoma (20%)
Malignancy: 10%
How does one test for an insunlinoma?
Check serum during 72 hour fast in the hospital; monitor for elevated insulin/c-peptide levels with hypoglycemia
What are treatment options for an insulinoma?
Surgical resection OR Diazoxide to suppress insulin secretion
Of the MEN1 pancreatic tumors, which are more often malignant than not? (2)
Glucagonomas and somatostatinomas
In which MEN 1 pancreatic tumor does the patient present with Necrolytic Migratory Erythema (NME)?
Glucagonoma; affects limbs, lips, lower abdomen, buttocks, perineum, groin
How does one diagnose a glucagonoma?
Clinical presentation with HYPERglycemia, hyperproteinemia, elevated fasting glucagon
Which MEN 1 pancreatic tumor presents with pancreatic cholera syndrome (Watery Diarrhea, Hypokalemia, Achlorydria)?
VIPomas
What is the clinical presentation of a VIPoma?
High-volume diarrhea, muscle weakness, lethargy, hyperglycemia, hypercalcemia, cutaneous flushing; episodic secretion, must measure multiple fasting levels
How does a somatostatinoma present?
Steatorrhea, diabetes, gallstones
How is a somatostatinoma diagnosed?
Elevated fasting somatostatin levels
How should one approach imaging modalities for neuroendocrine tumors? (Sequence, choice)
After biochemical confirmation, start with CT/MRI, then consider octreotide scan if a mass can’t be localized.
What is an octreotide scan?
Octreotide, a synthetic bioactive peptide similar to somatostatin, that can bind somatostatin receptors (which most neuroendocrine tumors express)
Treatment approach to neuroendocrine tumors?
Surgical resection, octreotide injection for VIPomas (and off-label use for insulinomas, glucagonomas, gastrinomas)
Multiple endocrine neoplasia syndrome that is: Autosomal dominant 1-10/100,000 Has an A and B subclassification Associated with defect in RET
MEN 2
What are the three parts of Sipple’s syndrome? (3) Which MEN is it associated with?
Hyperparathyroidism, pheochromocytoma, medullary thyroid carcinoma.
MEN 2A
What are the associated tumors in MEN2B? (4)
Pheochromocytoma, medullary thyroid carcinoma, mucosal neuromas, and Marfanoid habitus
A catecholamine-secreting tumor that arises from chromaffin cells of the adrenal medulla, associated with which syndrome?
Pheochromocytoma, MEN 2
A catecholamine-secreting tumor that arises in the sympathetic ganglia outside of the adrenal gland?
Paraganglioma
What is the classic triad of symptoms with a pheochromocytoma?
Episodic hypertension, headaches, diaphoresis
Rule of 10’s for pheochromocytoma (6):
10%: bilateral malignant familial in children extra-adrenal not associated with HTN
How does one screen for pheochromocytoma? (2 screening recommended)
Fractionated plasma metanephrines.
24 hour urine catecholamines + franctionated metanephrines.
Pheochromocytoma may be treated with:
Surgical resection with preoperative alpha-adrenergic blockade a week leading up to surgery (phenoxybenazmine)
then beta-adrenergic blockade after alpha blockade
In treating pheochromocytoma, why must one first administer an adequate alpha-blockade?
Unopposed alpha-adrenergic stimulation can lead to severe elevation in blood pressure and possibly a hypertensive crisis
A neoplasm of the parafollicular cells of the thyroid:
Medullary thyroid carcinoma
What does a MTC secrete?
Calcitonin
Treatment of MTC:
First screen for pheo before performing total thyroidectomy.
A polyglandular autoimmune syndrome that is: Autosomal recessive Linked to AIRE Has equal gender distribution Onset in infancy
Type I PGA
A polyglandular autoimmune syndrome that is: Polygenic Has some HLA association Higher prevalence in females Onset ages 20 - 40
Type II PGA
PGA where:
+Addison’s disease is seen in 60 - 72% of patients
+HypoPTH is common
+Hashimoto’s is rare
+T1DM is about 14%
+Primary hypogonadism is more common in females
+No hypophysitis reported
Type I PGA
PGA where: \+Addison's disease is see in 70% of patients \+HypoPTH is rare \+Hashimoto's is frequent \+T1D occurs in >50% of patients Primary hypogonadism is less frequent Hypophysitis is reported
Type II PGA
In which PGA type does one see:
Myasthenia gravis, stiff-man syndrome, and Parkinson’s?
Type II PGA
In which PGA type does one see:
Enamel hypoplasia, nail dystrophy, and tympanic membrane calcification?
Type I PGA
PGA I is also known as
Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED)
Need 2/3 of the following for diagnosis of PGA I:
Chronic mucocutaneous candidiasis
Autoimmune hypoPTH
Primary adrenal insufficiency
Less commonly occurring autoimmune diseases associated with PGA I:
Primary hypogonadism autoimmune hepatitis T1DM Vitiligo Autoimmune thyroid disease Pernicious anemia
Chvostek’s sign tests:
Hypocalcemia by tapping facial nerve to elicit contraction of facial muscles
Trousseau’s sign tests:
Hypocalcemia by eliciting carpal spasm with blood pressure cuff at 20mmHg above systolic BP for 3 minutes
An autoimmune process directed against melanocytes resulting in skin depigmentation
Vitiligo
Schmidt’s syndrome, which is more common in women and has no identifiable pattern of inheritance is also known as:
PGA II
Need 2/3 of the following to make a diagnosis of PGA II:
DM1 (GAD)
Addison’s disease
Autoimmune thyroid disease (TPO for hypo, TSI for hyper)
Less commonly occurring autoimmune diseases associated with PGA II:
Primary hypogonadism Myasthenia gravis Celiac disease Pernicious anemia Alopecia Vitiligo Hypophysitis
What are the three layers of the adrenal cortex and what do they produce?
Zona Glomerulosa: Mineralocorticoids
Zona Fasciculata: Glucocorticoids
Zona Reticularis: Adrenal androgens
Screening for adrenal insufficiency:
8 am cortisol
Normal is >10ng/dL
Diagnostic tests once cortisol screening indicates potential for adrenal insufficiency:
Rapid cosyntropin stimulation: administered IV or IM and cortisol is checked at 30 and 60 minutes. Normal >18ng/dL
If secondary is suspected:
Insulin-induced hypoglycemia test (dangerous, must be done with physician present)
Matyrapone stimulation test blocks 11 B-hydroxylase lowering cortisol levels and stimulating CRH to increase ACTH
Treatment of adrenal insufficiency with:
Glucocorticoids, prednisone
