Endocrine Flashcards
list the 6 hormones produced by the ANTERIOR pituitary
TSH: Thyroid-stimulating hormone or thyrotropin
PRL: Prolactin
ACTH: adenocorticotropic hormone or corticotropin
GH: Growth hormone
FSH: Follicle stimulating hormone
LH: Luteinizing hormone
the ______ pituitary is composed of modified glial cells and axonal processes extending from hypothalamic neurons
posterior
which hormones are produced by the posterior pituitary gland?
Oxytocin antidiuretic hormone (ADH)
Anterior pituitary hyperfunction is almost always associated with _______
adenoma
what conditions are associated with Hyperfunction of ACTH?
Cushings syndrome
Nelson syndrome
what conditions are associated with Hyperfunction of Growth hormone?
- Gigantism (children)
- Acromegaly (adults)
overproduction of Prolactin causes what conditions?
- Galactorrhea and amenorrhea (females)
- Sexual dysfunction, infertility
overproduction of TSH causes what condition?
Hyperthryoidism
overproduction of FSH and LH causes what conditions?
- Hypogonadism
- mass effects
- hypopituitarism
what are the 3 possible causes of Pituitary hypo-function?
A) Nonfunctional pituitary adenoma
B) Postpartum ischemic necrosis
(Need over 75% destruction)
C)Ablation/destruction by surgery, radiation, or adjacent tumor
What conditions result from a LACK of GH? Prolactin ? TSH ? ACTH ?
GH- dwarfism
Prolactin- no post-partum lactation
TSH- hypothryoidism
ACTH- Hypoadrenalism
what conditions can occur due to a lack of Gonadotropin production?
- Amenorrhea and infertility in women
- Decreased libido, impotence, and lack of pubic/axillary hair in men
there is no clinical manifestations for a lack of which hormone?
Oxytocin
a lack of ADH is associated with what disease?
Diabetes insipidus
Hypothalamic neurons produce which 2 hormones?
oxytocin
antidiuretic hormone (ADH)
the ________ pituitary is derived from neuroectoderm
posterior
_________ cells of the anterior pituitary produce growth hormone
somatotroph
Gigantism occurs before closure of what structures?
epiphyseal plates (growth plates) in the long bones
clinical features of gigantism:
Generalized increase in the size of the body
Arms and legs are disproportionately long
how is gigantism/acromegaly treated?
surgical removal of the adenoma
clinical features of acromegaly:
- Enlarged bones of the hands, feet, and face
- Prognathism, development of a diastema
- Hypertension and congestive heart failure may be seen
T/F: the prognosis for acromegaly is generally better than gigantism
FALSE
- acromegaly can cause congestive heart failure
- acromegaly = guarded prognosis
name the causes and features of dwarfism:
Causes:
- Failure of pituitary gland to produce growth hormone
- Lack of response to growth hormone by the patient’s tissues
Treatment:
- Short stature
- Small jaws and teeth
how can dwarfism be treated?
if lack of production of growth hormone is the problem, then hormone replacement therapy works
what is the normal histology of the thyroid glad?
Follicles filled with colloid
the thyroid gland Produces hormones that regulate what?
the RATE at which the body carries out its necessary functions
- “the bodies thermostat”
where is the thyroid gland located?
Located in the middle of the LOWER NECK, below the larynx and above the clavicles
- has bow-tie shape
T/F: You can’t always palpate a normal thyroid gland
True
how is PRIMARY hyperthyroidism diagnosed?
which hormones are reduced/increased
- Elevated TH
- decreased TSH
what causes Synthroid ?
Ingestion of exogenous thyroid hormone
what is graves disease?
AKA what is its etiologic characteristic
Diffuse toxic hyperplasia of the thyroid tissue
clinical features of hyperthyroidism are the result of what?
due to hypermetabolic state and overactivity of the sympathetic nervous system
clinical features of hyperthyroidism:
A) Hypermobility B) G-I hypermotility, malabsorption C) Tachycardia D) Nervousness, tremor, irritability E) Heat intolerance and excessive sweating F) Soft, warm, flushed skin
what clinical sign is indicative of Graves Disease?
Exophthalmos
bulging of the eyes
What is a “thyroid storm”? why can it be deadly?
- sudden onset of severe hyperthyroidism, usually triggered by stress.
- A medical emergency—patients often die of cardiac arrhythmias if untreated
______________ can be used to destroy overactive thyroid tissue
reactive iodine
_____________ is also known as diffuse toxic hyperplasia of the thyroid gland
Graves Disease
what groups are at risk for Graves disease?
** females
= 7X more likely
manifestations of graves disease:
A) Hyperthyroidism
B) Exophthalmos (40%)
C) Skin lesions
** pretibial myxedema ** (rash below knee)
what 3 things can cause a decrease in thyroid hormone production?
1) Iodine deficiency
2) Autoimmune destruction of thyroid
3) Ablation by surgery or radiation therapy
Autoimmune destruction of the thyroid leads to what disease?
Hashimoto’s thyroiditis
clinical features of hypothyroidism:
1) creatinism - if infant or early childhood
2) Mydxema - older children and adults
features of Myxedema:
late childhood & adult hypothyroidism
Generalized apathy Mental sluggishness—can mimic depression Obesity Cold intolerance Enlarged tongue
In HYPOthyroidism, when are serum TSH levels increased? when are they not increased?
A) Increased in primary cases
B) Not increased in cases caused by hypothalamic or pituitary disease
why must hypothyroidism be treated quickly in younger patients?
The damage to skeletal and nervous systems could become permanent
(creatinism)
characteristics of Hashimoto Thyroiditis :
- Female predominance (older women, genetic risk)
- Autoimmune; progressive destruction of gland
- Patients usually at risk for other autoimmune diseases and B-cell Non-Hodgkin lymphomas
characteristics of Hashimoto Thyroiditis :
- Female predominance (older women, genetic risk)
- Autoimmune; progressive destruction of gland
- Patients usually at risk for other autoimmune diseases and B-cell Non-Hodgkin lymphomas
T/F: patients with Hashimoto Thryoiditis have no established risk of development of thyroid neoplasm
True
__________ are the most common manifestation of thyroid disease
Goiters
enlargements of the thyroid gland
what causes goiters?
impaired synthesis of thyroid hormone
- Most often due to dietary deficiency of iodine
what are the most common clinical features of goiters?
** due to mass effects ** (growth of tissue masses)
Cosmetic problem
Airway obstruction
Dysphagia
Compression of vessels
what causes a “toxic goiter”?
occur when a hyper-functioning nodule develops within a longstanding goiter
- results in HYPERthyroidism
Characteristics of Thyroid neoplasms:
- Thyroid nodules are common
- Most nodules are non-neoplastic disease
- 1% of nodules are carcinomas
T/F: Thyroid Nodules in females and young patients are more likely to be neoplastic
FALSE
- males and young patients more likely to be neoplastic
what is the only known environmental link for thyroid neoplasms?
exposure to radiation in first 2 decades
what groups are at the highest risk for PAPILLARY Thyroid Carcinoma’s?
- ** Most common type of thyroid cancer
- FEMALES
- peaks in 30s-50s
which onconogene is mutated in patients with Papillary Thyroid Carcinomas?
RET proto-oncogene mutation
PATHOLOGY of Papillary Thyroid Carcinomas:
A) microscopically characterized by papillary projections
B) nuclear clearing - ORPHAN ANNIE nuclei
C) nuclear grooves
Follicular Thyroid Carcinoma s make up ___% of all thyroid neoplasms
10-20%
characteristics of Follicular Thyroid carcinomas:
- Older age than papillary; areas with dietary iodine deficiency
- May resemble a Follicular Adenoma
what type of thyroid neoplasm is Derived from the parafollicular (C) cells?
Medullary Thyroid Carcinoma
the course of Medullary thyroid carcinomas may be _____ or familial
sporadic
Both _________ and ___________ thyroid carcinoma types will show a mutation of the RET proto-onconogene
1) Papillary thyroid carcinoma
2) Medullary Thyroid Carcinoma
Patients with Medullary Thyroid Carcinomas will show an elevation of what hormone?
Increased serum calcitonin
makes sense- medullary carcinomas derived from PARAFOLLICULAR cells….. they secrete calcitonin
to diagnose FOLLICULAR thyroid carcinoma, you must see invasion through ____________, or into the _____________
- through the capsule
- into the blood vessels
