Rubin's 27: Endocrine

Question 1

Diabetes insipidus reflects a deficiency in what hormone?

Answer 1

ADH

Question 2

What kind of brain tumor is commonly associated with diabetes insipidus?

Answer 2

Craniopharyngioma –> destruction of the posterior pituitary (neurohypophysis)

Question 3

Small cell carcinoma of the lung is often associated with what paraneoplastic syndrome?

Answer 3

SIADH

Question 4

What is Sheehan syndrome?

Answer 4

Hypopituitarism caused by infarction (ischemic necrosis) of the anterior pituitary Can happen during pregnancy when it enlarges

Question 5

What is the most common endocrinopathy associated with pituitary adenoma?

Answer 5

Hyperprolactinemia Functional lactotrope adenomas lead to amenorrhea, galactorrhea and infertility Can cause loss of libido in men

Question 6

The symptoms of hypoparathyroidism (decreased serum calcium and decreased PTH) result from hypocalcemia, and cause:

Answer 6

Increased neuromuscular excitability: mild tingling in hands and feet, severe muscle cramps, laryngeal stridor, convulsions, as well as neuropsychiatric manifestations such as depression, paranoia, psychoses

Question 7

Lithium causes goiter how?

Answer 7

Suppresses thyroid hormone synthesis (nontoxic goiter)

Question 8

CAH ie 21-hydroxylase deficiency may result in impaired synthesis of what hormone?

Answer 8

Aldosterone –> salt-wasting CAH –> hypotension and dehydration and hyponatremia/hyperkalemia, increased renin secretion

Question 9

Name the dx: Sex-linked disease with severe immunodeficiency; Hypoplastic thymus; Eczema; Thrombocytopenia; Chronic RTIs, GI infections, Petechiae

Answer 9

Wiskott-Aldrich syndrome

Question 10

What causes DiGeorge syndrome?

Answer 10

Failure of development of the third and fourth branchial pouches resulting in agenesis or hypoplasia of the thymus and parathyroid glands, congenital heart defects, dysmorphic facies etc. Parathyroid agenesis –> convulsions (hypocalcemia) Thymic aplasia –> loss of T cells –> deficiency of cell-mediated immunity, particular susceptibility to candida infections

Question 11

Name the dx: Excessive secretion of PTH, such as from parathyroid adenoma; Stones in renal pelvis and/or ureter causing acute flank pain; Excessive loss of Ca from bones and enhanced Ca resorption by renal tubules; Can also be asymptomatic; Can be accompanied by mental changes such as depression, emotional lability, poor mentation and memory defects

Answer 11

Primary hyperparathyroidism

Question 12

What kind of cell is abundant in parathyroid neoplasm?

Answer 12

Chief cell

Question 13

Secondary parathyroid hyperplasia is encountered principally in patients with :

Answer 13

Chronic renal failure; –chronic hypocalcemia –> renal rention of phosphate –> compensatory hypersecretion of PTH –> parathyroid hyperplasia However… Vitamin D deficiency, intestinal malabsorption, Fanconi syndrome, renal tubular acidosis also possible

Question 14

Name the dx: C-cell-derived medullary thyroid carcinoma and chromaffin cell-derived pheochromocytoma; Hirschsprung disease (congenital megacolon); Variety of neural crest tumors; Elevated serum levels of PTH possible causing fractures

Answer 14

MEN-2A aka Sipple syndrome Mutations in RET protooncogene

Question 15

Name the dx: Adenoma of the pituitary; Parathyroid hyperplasia or adenoma; islet cell tumorsof the pancreas (insulinoma and gastrinoma)

Answer 15

MEN-1 aka Werner syndrome Mutation of the MEN-1 tumor suppressor gene

Question 16

Gastrinoma of the endocrine pancreas is aka:

Answer 16

Zollinger-Ellison syndrome

Question 17

How does hyperparathyroidism cause peptic ulcer disease?

Answer 17

Higher PTH –> higher serum calcium –> gastrin secretion up –> peptic ulcer disease

Question 18

Name the dx: umbilical hernia at birth; mental insufficiency secondary to congenital hypothyroidism; Can be due to lack of iodination of salt OR agenesis of the thyroid; Sluggishness; Low body temperature; Anemia

Answer 18

Cretinism

Question 19

Name the dx: Renal retention of phosphate –> hypocalcemia –> bone deformities such as bone pain, fractures, cysts, “brown tumors”

Answer 19

Osteitis fibrosa cystica due to secondary hyperparathyroidism (from renal insufficiency)

Question 20

Name the dx: Ovulatory failure; Progsterone deficiency; Irregular and excessive menstrual bleeding; ED/oligospermia in men Mxedema; Mental status changes; Coarse, brittle hair; Muscle weakness

Answer 20

Autoimmune thyroiditis

Question 21

Name the dx: thyroiditis featuring multinucleated giant cells; granulomatous; caused by a viral infection; self-limited

Answer 21

subacute aka DeQuervain thyroiditis

Question 22

Name the dx: thyroiditis featuring fibrosis and chronic inflammatory infiltrate; Progressive fibrosis in other locations possible; Patients complain of hoarseness or stridor;

Answer 22

Reidel thyroiditis

Question 23

Name the dx: thyroiditis featuring lymphocytic infiltrates

Answer 23

Hashimoto thyroiditis

Question 24

Older patients with nontoxic goiter sometimes go on to develop:

Answer 24

Hyperthyroidism

Question 25

Name the dx: Most common thyroid tumor in younger women; tendency to metastasize to regional lymph nodes; Surgery is usually curative

Answer 25

Papillary carcinoma of the thyroid

Question 26

Name the dx: Branching papillae lined by epithelial cells with clear (ground glass or Orphan Annie) nuclei and fibrovascular cores; Psamomma bodies (calcospherites) also possible

Answer 26

Papillary carcinoma of the thyroid

Question 27

Name the dx: Most frequent cause of hyperthyroidism in young adults; Diffuse goiter, exopthalmous; stimulating IgG antobodies that bind to TSH receptors on the pm of thyrocytes

Answer 27

Graves disease

Question 28

Name the dx: Follicular hyperplasia with scalloping of colloid of thyroid gland

Answer 28

Graves disease

Question 29

Name the dx: Most common tumor of the thyroid; Patient is euthyroid; Benign; Isolated small nodule; Proliferation of thyroid follicles

Answer 29

Follicular adenoma

Question 30

Name the dx: C-cell thyroid cancer; C-cells secrete calcitonin which lowers serum calcium; Polygonal, granular cells separated by distinct vascular stroma; Stromal amyloid is a distinct feature of this cancer (deposition of procalcitonin); Patients suffer multiple endocrine paraneoplastic syndromes including carcinoid syndrome and Cushing syndrome; Water diarrhea common

Answer 30

Medullary thyroid carcinoma (MTC) Can occur in patients with MEN-2

Question 31

Name the dx: Purely follicular thyroid cancer; Well-defined, encapsulated tumor; Resembles follicular adenoma, but with more microfollicles or trabecular pattern

Answer 31

Follicular thyroid carcinoma (FTC)

Question 32

Name the dx: Large masses of the thyroid gland; Poorly circumscribed; Frequently extends into the soft tissue of the neck

Answer 32

Anaplastic carcinoma of the thyroid

Question 33

Name the dx: Malignant tumor of the neural crest; Can originate in the adrenal medulla or sympathetic ganglia; Pseudorosettes featuring tumor cells frequently seen clustering around small vessels, “blue cell” appearance; Tumor cells may secrete catecholamines (excreted as vannilylmandelic acid in the urine);

Answer 33

Neuroblastoma **amplification of n-myc

Question 34

A dexamethasone suppression test that reduces corticotropes suggests what kind of tumor?

Answer 34

Pituitary (ACTH-secreting) adenoma

Question 35

An unsuccessful dexamethasone test suggests a tumor where?

Answer 35

Adrenal cortex fasiculata - glomerulosa - aldosterone