- Flashcards
(147 cards)
1
Q
what is polyuria
A
pee more than usual
2
Q
what happens to blood pressure in adrenal insufficiency
A
decreases
3
Q
conductor of the endocrine orchestra
A
pituitary
4
Q
structures of hormones
A
polypeptide, glycoprotein, steroid or amine
5
Q
what causes release of hormones
A
intracellular calcium
6
Q
hypothalamic releasing hormones are released into the
A
pituitary portal system
7
Q
only unbound/bound hormone is biologically active
A
unbound
8
Q
cell surface receptors contain – secretions
A
hydrophobic
9
Q
most peptide hormones activate via
A
G protein coupled receptors
10
Q
steroid and thyroid hormones act via
A
nuclear receptors
11
Q
TRH and TSH increases release of
A
T3 and T4
12
Q
Role of TSH
A
stimulates increased iodine uptake by the thyroid
13
Q
t3 and t4 bind to what kind of receptors
A
nuclear
14
Q
secondary gland failure is due to
A
pituitary disease
15
Q
in secondary gland failure, the pituitary hormone is not
A
suppressed so negative feedback not really working in pituitary disease
16
Q
hormones are measured by
A
biochemical assays in lab
17
Q
not possible to measure
A
hypothalamic hormones
18
Q
circulating levels of most hormones are
A
very low
19
Q
how do immunoassays work
A
highly specific antibodies bind to hormone and this interaction is measured
20
Q
immunoassays definitely have their
A
limitations
21
Q
in women who are pregnant or on the pill can give false impression of
A
22
Q
in women who are pregnant or on the pill can give false impression of
A
hypercortisolaemia due to high oestrogen levels
23
Q
in people with diabetes mellitus may give impression of
A
androgen deficiency due to Low testosterone levels
23
Q
in people with diabetes mellitus may give impression of
A
androgen deficiency due to Low testosterone levels
24
thyroid hormones show what kind of secretion
continuous with very little variation
25
GH, Lh and FSH show
pulsatile secretion
26
cortisol levels vary greatly with highest levels being in the morning and lowest
overnight
27
stress increases
acth and cortisol, GH, prolactin, adrenaline and noradrenaline
28
secretion of -- and -- is increased during sleep
GH and prolactin
29
what 2 hormones decreases after digestion of food
testosterone and GH
30
testosterone should be. measured
before 11am in the fasting state
31
cortisol should be checked
between 8 and 10 am to exclude hypoadrenalism and and at midnight to exclude cushings
32
what hormones vary with menstrual cycle
Lh/FSH, oestrogen and progesterone
33
renin and aldosterone vary with
sodium , age and posture
34
dexamethasone decreases
cortisol
35
dopamine restricts production of
prolactin
36
ADH and oxytocin are secreted in hypothalamus but are stored in
posterior pituitary
37
oxytocin produces
milk ejection and uterine myometrial contraction
38
most common cause of pituitary disease
pituitary tumours
39
most common presentation of prolactinoma
galactorrhea(milky nipple discharge), amenorrhoea (lack of period), erectile dysfunction, hypogonadism(sex glands produced little if any sex hormones)
40
central obesity associated with
cushings disease
41
nelsons syndrome occurs
post adrenalectomy
42
excess acth secretion occurs in
cushings disease and nelsons syndrome
43
acidophil
acromegaly
44
basophil
Cushings disease and nelson syndrome
45
usual treatment of choice for pituitary tumour
surgery via transphenoidal route and large tumours through trans cranial route usually transfrontal
46
what drugs can cause shrinkage of particular tumour types
somatostatin analogue eg octreotide and or dopamine agonists eg cabergoline particularly in prolactinomas
47
replacement therapy for adrenal
hydrocortisone
48
replacement for deficiency in gonadal in male and what for female
male - testosterone and female - oestrogen/ progestogen
49
replacement for fertility
HCG plus FSH
50
if thirsty given
desmopressin
51
if breasr deficiency eg prolactin inhibition give
dopamine agonist eg cabergoline
52
reduction of excess hormone for acromegaly treatment drug
somatostatin analogue
53
dopamine agonists for
prolactinomas
54
most common mass lesion of pituitary
pituitary adenomas
55
another pituitary mass lesion
craniopharyngioma
56
arises from rathkes pouch
craniopharyngioma and is a cystic tumour
57
often from tumour growth where there is multiple deficeiceis in these hormones what hormones first affected
GH and gonadatrophins
58
last affected
tsh and acth
59
hypoadrenalism causes
mild hypotension, hyponatraemia and cardiovascular collapse during severe intercurrent stressful illness
60
-- leads to loss of libido (sex drive), sexual hair, amenorrhoea dn erectile dysfunction and eventually osteoporosis
hypogonadism
61
pallor with hairlessness
panhypopituitarism
62
loss of smell
kallmanns syndrome
63
3 zones of the adrenal cortex
zona glomerulosa, fasciculata and reticularis
64
zona glomerulsoa secretes
aldosterone
65
inner medulla synthesises, stores and secretes
catecholamines
66
zona fasciculata and reticularis produce
glucocorticoids, cortisol, sex steroids and androgen
67
catecholamines such as
adrenaline and noradrenaline
68
main role of mineralocorticoids
on extracellular balance of sodium and potassium in kidney
69
glucocorticoids main effects on
carbohydrate metabolism
70
what contains melanocytes stimulating hormone
ACTH
71
circulatimg acth stimulates -- in the adrenal
cortisol
72
crH - acth - -----
cortisol
73
following adrenalectomy or other adrenal damage eg Addisons disease, cortisol secretion is absent or reduced and acth levels will
rise
74
--- secretion is mainly controlled by the renin angiotensin system
mineralcorticodi
75
-- increases in response to stress
cortisol
76
administration of dexamethasone does what to CRH and ACTH levels and thus cortisol
decreases them
77
dexamethasone test for
cushings syndrome
78
for stimulation tests what is given
synthetic ACTH to stimulate adrenal cortisol production
79
cushings syndrome most often iatrogenic Fromm administering what
steroids
80
Cushings disease is caused by excess secretion of ACTH from a
pituitary adenoma
81
cushings syndrome divided into 2 categories
1. increased circulating ACTH from the pituitary known as cushings disease (65%) or ectopic non pituitary tumour acth producing tumour from elsewhere in the body (10%)
2. excess of cortisol secretion by an adrenal tumour(25%)
82
pigmentation in cushings only occurs
with acth dependent causes most frequently in ectopic acth syndrome
83
-- is common in all causes of cushings syndrome
hypertension
84
what is common with ectopic acth secretion in cushings
hypokalaemia and impaired glucose tolerance and pigmentation
85
signs more specific to Cushings
plethora (moon face), thin skin, bruising, proximal myopathy
86
confirm diagnosis for cushings with
48hr low dose dexamethasone test
87
why is overnight dexamethasone test used as more of an initial screening test in cushings
as has a higher false positive rate and takes less time.
88
tests for cushings
48hr low dose dexamethasone test
24hr urinary free cortisol measurements
circadian rhythm
89
classic ectopic acth syndrome of cushings is
pigmentation ,weight loss, hypokalaemia, diabetes and plasma acth levels above 200ng/L
90
in cushings severe hirsutism suggests
adrenal tumour
91
for a dexamethasone test, failure of significant plasma cortisol suppression suggests an
ectopic source of acth ( or an adrenal tumour)
92
exaggerated ACTH and cortisol response to CRH suggests
pituitary dependent cushings disease
93
untreated cushings syndrome can cause death from
venous thromboembolism, hypertension, MI, infection and heart failure
94
drugs to control cortisol hypersecretion prior to surgery
usual drug is metyrapone but ketocanazole can also be given
95
treatment of choice for cushings disease
transphenoidal removal of the tumour
96
what is mainly used after failed pituitary surgery in
external pituitary irradiation
97
what is last resort in treatment of cushings disease
bilateral adrenalectomy
98
cushions due to adrenal adenomas should be
resected laparoscopically
99
if source of acth is not clear in cushings , cortisol hyperesecretion should eb controlled with medical therapy until diagnosis eg
metyrapone or ketoconazole
100
what occurs after 20% of cases after bilateral adrenalectomy for cushings disease
nelson syndrome
101
when is there destruction of the entire adrenal cortex
Addisons disease
102
if entire adrenal cortex is destructed then what are reduced
glucocorticoid, mineralocorticoid and sex steroid production
103
what generally remains intact in hypothermic pituitary disease
mineralocorticoid secretion also sex steroid
104
in Addisons disease, reduced cortisol levels lead through feedback to increased CRH and __ production, the latter being directly responsible for the hyperpigmentation
ACTH
105
Addisons disease is usually caused by
autoimmune disease
106
most common cause of primary adrenal insufficiency in kids is
congenital adrenal hyperplasia
106
most common cause of primary adrenal insufficiency in kids is
congenital adrenal hyperplasia
107
what is the predominant sign in Addisons
pigmentation (dull, slaty, grey-brown) especially of new scars and palmar creases and postural systolic hypotension
108
if adddisons disease is suspected, investigation is
urgent
109
what is given to suspected add-ons disease if hypotensive or seriously ill
hydrocortisone and IV saline
110
random cortisol. measurement of below -- during the day is highly suggestive of Addisons
100nmol/L
111
ACTH stimulation test should be performed in
Addisons
112
absent or impaired cortisol response to acth stimulation test confirms presence of hypoadrenalism but does not
differentiate Addisons from acth deficiency or iatrogenic suppression by steroid medication
113
what may be normal but classical seen in Addisons
hyponatraemia, hyperkalaemia and high urea
114
long term treatment of Addisons is with
glucocorticoid and mineralocorticoid replacement
115
is measuring cortisol levels during the day for Addisons while on replacement therapy recommended as an assessment for dose adequacy
NO
116
patients should double dose of steroid in Addisons during
intercurrent illness
117
long term steroid therapy can lead to
acth suppression
118
hydrocortisone needs to be started before
t4 replacement
119
in secondary hypoadrenalism, acth levels are
low
120
disorder resulting in a defiency of an enzyme in the cortisol synthetic pathway
congenital adrenal hyperplasia
121
in CAH, as cortisol secretion is reduced,
acth is increased causing adrenal hyperplasia
122
what test for congenital adrenal hyperplasia
synacthen test
123
long term steroids (greater than 3 weeks) will often mimic
cushings syndrome
124
steroids can affect endocrine system by causing what
weight gain and glycosuria(urine contains lots of glucose)/hyperglycaemia/ diabetes
125
what accounts for 5-10% of all hypertension
primary hyperaldosteronism
126
what is characterised by excess aldosterone, leading to sodium retention, potassium loss and the combination of hypokalaemia and hypertension
primary hyperaldosteronism
127
secondary aldosteronism is when there is
excess renin
128
most common cause of primary hyperaldosteronism
bilateral adrenal hyperplasia followed by conns syndrome ( adrenal adenomas)
129
usually presentation for primary hyper aldosteronism is simply
hypertension
130
screening test for primary hyperaldosteronism
plasma aldosterone :renin ratio
131
2 main causes of hyperaldosteronism
adrenal adenoma or hyperplasia
132
how to treat an adenoma and hypoerplasia causing primary hyperaldosteronism
adenoma - laparoscopically
hyperplasia- aldosterone anatoginst (spironolactone)
133
increase in levels in urine of --- is a marker of abnormal hyper secretion of them
catecholamines
134
rare tumours of the sympathetic nervous system
pheochromocytoma and paraganglioma
135
metabolism of virtually all nucleated cells of many tissues is controlled by the
thyroid hormones
136
thyroid gland moves on
swallowing
137
embryonically what originates from the base of the tongue and descends into the middle of the neck
thyroid gland
138
does thyroid gland have rich blood supply
yes
139
thyroid gland consists of
follicles
140
colloid is the
iodinated glycoprotein thyroglobulin
141
parafollicular cells contain
c cells
142
what is a prohorome
T4
143
iodine + thyroglobulin =
T3 and t4
144
majority of t3 and t4 in plasma is bound to hormone binding proteins
true
145
only -- hormone is available for action in the target tissues where t3 binds to nuclear receptors
free
