Rubin's 27: Endocrine Flashcards
Diabetes insipidus reflects a deficiency in what hormone?
ADH
What kind of brain tumor is commonly associated with diabetes insipidus?
Craniopharyngioma –> destruction of the posterior pituitary (neurohypophysis)
Small cell carcinoma of the lung is often associated with what paraneoplastic syndrome?
SIADH
What is Sheehan syndrome?
Hypopituitarism caused by infarction (ischemic necrosis) of the anterior pituitary Can happen during pregnancy when it enlarges
What is the most common endocrinopathy associated with pituitary adenoma?
Hyperprolactinemia Functional lactotrope adenomas lead to amenorrhea, galactorrhea and infertility Can cause loss of libido in men
The symptoms of hypoparathyroidism (decreased serum calcium and decreased PTH) result from hypocalcemia, and cause:
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
Lithium causes goiter how?
Suppresses thyroid hormone synthesis (nontoxic goiter)
CAH ie 21-hydroxylase deficiency may result in impaired synthesis of what hormone?
Aldosterone –> salt-wasting CAH –> hypotension and dehydration and hyponatremia/hyperkalemia, increased renin secretion
Name the dx: Sex-linked disease with severe immunodeficiency; Hypoplastic thymus; Eczema; Thrombocytopenia; Chronic RTIs, GI infections, Petechiae
Wiskott-Aldrich syndrome
What causes DiGeorge syndrome?
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
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
Primary hyperparathyroidism
What kind of cell is abundant in parathyroid neoplasm?
Chief cell
Secondary parathyroid hyperplasia is encountered principally in patients with :
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
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
MEN-2A aka Sipple syndrome Mutations in RET protooncogene
Name the dx: Adenoma of the pituitary; Parathyroid hyperplasia or adenoma; islet cell tumorsof the pancreas (insulinoma and gastrinoma)
MEN-1 aka Werner syndrome Mutation of the MEN-1 tumor suppressor gene
Gastrinoma of the endocrine pancreas is aka:
Zollinger-Ellison syndrome
How does hyperparathyroidism cause peptic ulcer disease?
Higher PTH –> higher serum calcium –> gastrin secretion up –> peptic ulcer disease
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
Cretinism
Name the dx: Renal retention of phosphate –> hypocalcemia –> bone deformities such as bone pain, fractures, cysts, “brown tumors”
Osteitis fibrosa cystica due to secondary hyperparathyroidism (from renal insufficiency)
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
Autoimmune thyroiditis
Name the dx: thyroiditis featuring multinucleated giant cells; granulomatous; caused by a viral infection; self-limited
subacute aka DeQuervain thyroiditis
Name the dx: thyroiditis featuring fibrosis and chronic inflammatory infiltrate; Progressive fibrosis in other locations possible; Patients complain of hoarseness or stridor;
Reidel thyroiditis
Name the dx: thyroiditis featuring lymphocytic infiltrates
Hashimoto thyroiditis
Older patients with nontoxic goiter sometimes go on to develop:
Hyperthyroidism
Name the dx: Most common thyroid tumor in younger women; tendency to metastasize to regional lymph nodes; Surgery is usually curative
Papillary carcinoma of the thyroid
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
Papillary carcinoma of the thyroid
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
Graves disease
Name the dx: Follicular hyperplasia with scalloping of colloid of thyroid gland
Graves disease
Name the dx: Most common tumor of the thyroid; Patient is euthyroid; Benign; Isolated small nodule; Proliferation of thyroid follicles
Follicular adenoma
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
Medullary thyroid carcinoma (MTC) Can occur in patients with MEN-2
Name the dx: Purely follicular thyroid cancer; Well-defined, encapsulated tumor; Resembles follicular adenoma, but with more microfollicles or trabecular pattern
Follicular thyroid carcinoma (FTC)
Name the dx: Large masses of the thyroid gland; Poorly circumscribed; Frequently extends into the soft tissue of the neck
Anaplastic carcinoma of the thyroid
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);
Neuroblastoma **amplification of n-myc
A dexamethasone suppression test that reduces corticotropes suggests what kind of tumor?
Pituitary (ACTH-secreting) adenoma
An unsuccessful dexamethasone test suggests a tumor where?
Adrenal cortex fasiculata - glomerulosa - aldosterone
