Endocrine

Question 1

Name the mealtime insulin analogs

Describe their onset/ offset

Answer 1

Glulisine, Aspart, Lispro

They have rapid onset and offset of action, mimicking physiologic postprandial insulin secretion

Question 2

Describe the structure of the mealtime insulin analogs

Answer 2

AA substitution at the C terminal end of the B chain

Question 3

Major SEs of Corticosteroids

Answer 3

1. Immunosuppression (except with neutrophilia!!)
2. Corticosteroid-induced psychosis

Question 4

The 22q11.2 microdeletion associated with DiGeorge, causes what embryological component(s) not to develop?

Answer 4

3rd and 4th branchial pouches

Question 5

Describe the Chvostek sign and the Trousseasu sign associated with DiGeorge Syndrome

Answer 5

The hypocalcemia assc. with DGS leads to increased neuromuscular excitability.

Chvostek sign- tapping on the facial nerve elicits twitching of the nose and lips

Trousseau sign- inflation of the BP cuff leads to carpal spasm

Question 6

Tx of Acute Adrenal insufficiency

Answer 6

Hydrocortisone or dexamethasone

Question 7

Lung mass + hyponatremia, is suggestive of what?

Answer 7

SIADH (secondary to Small cell lung carcinoma)

Question 8

What is rT3 and what is it created from?

Answer 8

An inactive form of T3, that is generated almost entirely from peripheral conversion of T4

Question 9

What effect does expgenous steroid abuse have on hematocrit?

Answer 9

Increases hematocrit

Question 10

In Kallmann syndrome, there is an absence of GnRH secretory neurons in the _____________

Answer 10

hypothalamus

Question 11

Finasteride MOA and indication

Answer 11

MOA: 5-alpha-reductase inhibitor that suppresses conversion of testosterone to DHT

Ind: BPH, Androgenetic alopecia

Question 12

Hypoglycemia with an elevated insulin and low C-peptide level, suggests what?

High C-peptide level?

Answer 12

Low: exogenous insulin injection

High: insulin secretagogue or insulin-secreting tumor

Question 13

Xanthomas are found where? What are they associated with?

Answer 13

These yellowish macules/papules are found on the medial eyelids. They are accumulations of macrophages + cholesterol/ TG and are assc. with hyperlipidemia/ dyslipidemia

Question 14

Where is ADH synthesized? Is this the same location, or a different location from where it is stored?

Answer 14

In the hypothalamus. It is then transported, to the posterior pituitary for storage and later release into the circulation.

Only hypothalamic damage will be enough to cause central Diabetes insipidus

Question 15

Leuprolide MOA

Answer 15

Continuous GnRH agonist

Question 16

What is the most effective preventative intervention in almost all patients?

Answer 16

Smoking cessation

Question 17

How do chronically elevated FFA levels contribute to insulin resistance?

Answer 17

By impairing insulin-dependent glucose uptake and increasing hepatic gluconeogenesis

Question 18

How do OC treat hirsutism?

Answer 18

They suppress pituitary LH secretion and subsequently decrease ovarian androgen production

Question 19

What are the key effects of uncontrolled gestational diabetes on the fetus?

Answer 19

1. Beta cell hyperplasia due to increased trans-placental glucose delivery to the fetus (leads to hypoglycemia at birth)
2. Fetal macrosomia (large size at birth!)

Question 20

Familial Hypocalciuric Hypercalcemia (FHH)

What is it?

Describe the associated receptor?

Answer 20

A benign autosomal dominant disorder casued by a defective calcium-sensing receptor (G-protein coupled), which is suppose to regulate PTH secretion. Defect raises the Ca2+ threshold

Question 21

Elevated prolactin levels (from a prolactinoma), directly suppress what?

Answer 21

GnRH

Question 22

Following cleavage of pro-insulin, what is the fate of insulin and C-peptide?

Answer 22

They are both stored in islet cell secretory granules unti they are secreted in equimolar amounts

Question 23

Phosphorylation of what residues (and via what?), leads to insulin resistance?

Answer 23

Phosph. of serine and threonine residues of insulin receptor and insulin receptor substrate by serine kinase, leads to insulin resistance

Question 24

17a-hydroxylase def.

Presentation?

Answer 24

Boy appear phenotypically femaile at birth, but girls develop normally. (Result of dec. androgen, estrogen, and cortisol synthesis)

Patients present with hypogonadism, HTN, and hypokalemia