Endocrine Part I Flashcards
What are factors released the pitutiary gland that stimualts the production of hrmones from endocrine glands?
Trophic factors
What are the general classification of ALL endocrine disorders?
Hypo/hyperfunctioning of the endocrine organ
Mass lesions/neoplasms
Autoimmune disorders
Infections —> these are rare
WHat is ADH for?
Water retention, Na excretion
What are the 4 clinical manifestations of pituitary diseases?
Hyperpituitarism
Hypopituitarism
Local mas effects
Decreaesd & Increased secretion of AHD
What are the 2 types of neoplasms of hyperitutarism? What is their difference?
Pituitary adenoma - functioning/non-functioning
Pitutiary carcinoma - hyperfuncitoning pituitary (PRL & ACTH)
What is the diff between functioning and non-functioning pituitary adenomas?
Functioning - hormone excess & clinical manifestations
Nonfunctioning - w/o clinical sx of hormone excess
What are the genetic alteration in pituitary hormones? There are 7 genes
GNAS - GH adenomas
PKAR1A - GH adenomas & PRL adenomas
CYclin D1 = Aggresive adenomas
HRAS = Pituitary adenomas
MEN1 = GH adenomas, PRL adenomas, ACTH adenomas
CDKN1B = ACTH adenomas
AIP = GH adenomas
RB (retinoblatoma) = Aggressive adenomas
What genetic alterations is one of the most common alterations seen in pituitary adenomas?
G-protein mutations
WHat is the gross morphology of pituitary adenomas?
Typical: soft & well-circumscribed
Smaller = confined to the sella turcica
Larger = extend superiorly thorugh the diaphram of sella into the suprasellar region
Invasive/Aggressive = could infiltrate the neighboring tissues
What is the histology of pituitary adenomas?
Only one typical cell
Uniform polygonal cells arranged in sheets or cords
Soft gelatinuous consistency
What is the key characterisitc of pituitary adenomas?
cellular monomorphism + absence of reticular network
What is the most common type of hyperfunctioning adenoma?
Lactotroph adenomas
What are the histological features of lactotroph adenoma?
Sparsely granulated
Has chromophobe cells
What are the diff pituitary adenomas?
Lactotoroph adenoma
Somatotroph adenomas
Corticotroph adenoma
GOnadotroph adenomas
Thyrotoph adenoma
Non-funcitoning adenoma
What is the clinical cours eof lactotoroph adenoma?
GAL = common in girls sooo…..
Galactorrhea
Amenorrhea
Loss of libido & sexual function
How do u differentiate physiologic hyperprolactinemia from Lactotroph hyperplasia?
If physiologic HYPERprolactinemia —> seen often in pregnancy & breastfeeding women
Lactototrph hyperplasia => Pathologic
What is the 2nd most common funcitoning adenoma and presents w/ GIGANTISM in children & ACROMEGALY in adults?
Somatotroph adenomas
-> remember sa GH to
What is the morphology of Somatotroph adenomas?
Monomorphic => Densely granulated
Sparsely granulated => Chromophobe cells
Bihormonal => Mammosomatotrophs (PRL & GH)
WHat are the causes of HYPOpitutarism?
Tumors & other masses
Traumatic brain injury & subarachnoid hemorrhage
Pituitary surgery or radiation
Pitutiary apoplexy
Ischemic necrosis or Sheehan’s syndrome
Rathke’s cleft cyst
Empty sella syndrome
Hypothalamic lesions
Inflammatory disorders & infections
Genetic Defects
What are the 2 types of Empty sella syndrome?
Primary empty sella => defect in the dipahragm sella allows the arachnoid mater & CSF to HERNIATE into the sella —> women w/ hx of multiple pregnancies
SEcondary empty sella => mass enlarges the sella —> loss of pitutiary function
What are the manfiestations of hypopituitarism?
Gonadotropin loss —> amenorrhea, inferitlity in women, loss of libido in men
TSH & ACTH def -> simialr to hypothyroidism
PRL deficiency
MSH deficiency
What are the different local mass effects in the pituitary gland?
Visual field abnormlaities
Elevated ICP —> headache, nausesa, vomiting
Obstructive hydrocephalus & seizures
Pituitary apoplexy —> acute hemorrhages into an adenoma —> rapid enlargement of lesion
What are the diff posterior pitutary syndromes?
Diabetes inspidus —> Central & Nephrogenic DI
SIADH
How do u diffenretiate Diabetes inspidus from SIADH?
Urinary output
= HIGH: Diabetes Inspidius
= LOW: SIADH
Levels of ADH
= HIGH: SIADH
= LOW: DI
Serum Na
= HIGH: DI
= LOW: SIADH
Hydration status
= HIGH (over hydrated): SIADH
= LOW: DI
Both will present with excessive thirst
What neoplasm may present as DI or SIADH? What are the common implicated tumors of this neoplasm?
Hypothalamic Suprasellar tumors
Implicated tumors:
- Gliomas
- Cranipharyngiomas
What are the different pathologies of the thyroid gland?
Hyperthyroidism
Hypothyroidism
Thyroiditis
Riedel’s thryoiditis
Graves’ disease
Goiters
Neoplams of the TG
How would u characterize thyrotoxicosis?
Elevated levels of free T3 & T4
Hypermetabolic state
What are the most common causes of thyrotoxicosis?
Diffuse hyperplasia of the thyroid assoc w/ Graves dis
Hyperfunctional multinodular goiter
Hyperfunctional thyroid adenoma
WHat are the clinical features of thyrotoxicosis?
INC in the basal metabolic rate
Cardiac manifestations
Overactivity of the sympathetic NS
Ocular changes
Thyroid storm
Apathetic hyperthyroidism
How do we diagnose px w/ THyrotoxicosis?
Low TSH, INC T3 & T4
What causes hypothyroidism?
structural or functional derangement that interferes with the production of thyroid hormone
WHat are the 3 causes of primary hypothyroidism?
Congenital hypothyroidism
Autoimmune hypothyroidism
Iatrogenic hypothyroidism
What are possible defective steps of congenital hypothyroidism? Other causes?
Iodide transport into thyrocytes
Organificaiton of iodine
Processing to form hormonally active T3&T4
Other causes:
- Complete absence of thyroid parenchyma (thyroid agenesis)
Whata causes secondary hypothyroidism?
Central hypothyroidism
Deficiencies of TSH
Deficiencies of TRH
What is cretinism? What are its clinical manfiestations?
hypothyroidism that developed during infancy/childhood
common in regions where dietary iodine deficiency is endemic
Severe intellectual disability, short stature, coarse facial features, protruding tongue, umbilical hernia
What type of hypothyroidism develops in older children/adult aka Gull’s disease? What are the clin manifestations of this dis?
Myxedema
Mimic depression
Listless, cold intolerant, frequently overweight, DEC sympathetic activity
What is the histologic feature of Myxedema?
Accumulation of Glycosaminoglycans, & hyaluronic acid
What are the 3 groups of thyroiditis?
Hashimoto’s thyroiditis
Granulomatous thyroiditis
Subacute lymphocytic thyroiditis
What type of thyroiditis is an autoimmune disorder that results in destruction of the TG & major cause of non-endemic goiter in the pediatric population?
Hashimoto’s thyroiditis
What causes Hashimoto’s thyroiditis?
Breakdown in self-tolerance to thyroid autoantigens
INC suscpetibility to CTLA4, PTPN22, & IL2RA
CD8 CTX Tcell med death
Cytokine-mediated cell death
What are the morphological features of Hashomoto’s thyrodiitis?
Gross:
- Thyroid is diffusely enlarge, capsule intact
Histology:
- Extensive inflammation of the parenchym
- Thyroid follicles are atrophic
- Hurthle cells w/ heterogenous lymphocytes
What cells are pathognomonic for Hashimotos thyroiditis?
Hurthle cells
What are the clinical features of Hashimotos thyroiditis?
painless enlargement of thyroid
INC T3, T4, uptake of radiactive iodine
DEC TSH
What is aka as De Quervain Thyroiditis & occurs less frequently as Hashimoto?
Granulomatous thyropiditis
What causes Granuloamtous thyroiditis? What is its morphology?
Viral infections (URTI)
Gross: unilateral or bilateral enlargement & firm TG
Histo
- patchy and depends on stage of disease
- multinucleated Giant cells enclose pools of coloid