Diseases of the Endocrine System Flashcards

(68 cards)

1
Q

What is the role of the endocrine glands?

What is paracrine and autocrine secretion?

A

endocrine glands secrete hormones directly into the blood stream and act systemically

paracrine system secretes hormones that act locally

autocrine secretion affects the cell secreting the protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where is the pituitary gland situated?

What does it weigh?

A

situated in the sella turcica beneath the hypothalamus

it weighs between 500 - 1000 mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the 2 parts of the pituitary gland?

A

anterior:

  • 75% of the gland is formed by the anterior lobe
  • this is formed by an outpouching of the oral cavity (Rathke’s pouch)

posterior:

  • 25% of the pituitary gland is the posterior lobe
  • this is formed by downgrowth of the hypothalamus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is adenohypophysis?

A

it is another term for the anterior part of the pituitary gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is meant by neurohypophysis?

A

another term for the posterior lobe of the pituitary gland

it stores and releases oxytocin and vasopressin produced in the hypothalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the different causes of anterior pituitary hypofunction?

A
  1. tumours - non-secretory adenoma, metastatic carcinoma
  2. trauma
  3. infarction
  4. inflammation - granulomatous, autoimmune, other infections
  5. iatrogenic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the majority of primary pituitary tumours?

What causes the effects of the tumour?

A

the vast majority of adenomas are benign

they may be derived from any hormone producing cell

if functional, the clinical effect is secondary to the hormone being produced

local effects are due to pressure on the optic chiasma or adjacent pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 3 different types of anterior pituitary adenoma?

A

prolactinoma:

  • this is common
  • causes galactorrhoea and menstrual disturbance

growth hormone secreting:

  • causes gigantism in children and acromegaly in adults

ACTH secreting:

  • Cushing’s syndrome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the anatomy of the thyroid gland like?

How much does it weigh?

A

bilobed organ joined by an isthmus encased in a thin fibrous capsule

it is located at the level of the 5th, 6th and 7th vertebrae in the anterior neck and in close proximity to the trachea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the weight of the thyroid gland?

A

average weight is 18g in adult males and 15g in adult females

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the anatomical relationships of the thyroid gland?

A

abuts the thyroid cartilage of the larynx

the recurrent laryngeal nerve is located in the tracheo-oesophageal groove close to the posterior aspect of the lateral lobes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Label the diagram

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Label the diagram

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the origin of the thyroid gland like?

A

it has 2 parts

the main part migrates from the foregut to the anterior neck

the ultimobranchial body forms in branchial arches and fuses with the main bit laterally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does the remnant of the thyroid gland in the foregut form?

A

foramen caecum

this is at the junction between the anterior 2/3 and posterior 1/3 of the tongue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is Hashimoto’s?

(chronic lymphocytic thyroiditis)

Who is more commonly affected?

A

an autoimmune chronic inflammatory disorder associated with diffuse enlargement and thyroid autoantibodies

it is more common in females

peak age is 59 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens in Hashimoto’s disease?

A

there is a diffusely enlarged non-tender gland

lymphocytic infiltration of thyroid parenchyma, often with germinal centre formation

many patients become hypothyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What clinical feature is raised in Hashimoto’s?

What are the increased risks associated with this condition?

A

serum thyroid antibodies are elevated

there is an 80 fold increased risk of thyroid lymphoma

there is an increased risk of papillary carcinoma of the thyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is diffuse hyperplasia (Graves’ disease)?

Who tends to be more affected?

A

an autoimmune process results in clinical hyperthyroidism and diffuse hyperplasia of the follicular epithelium

it is more common in females

peak in third and fourth decades

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the physical findings in Graves’ disease?

A
  1. pretibial myxoedema
  2. hair loss
  3. wide-eyed stare or proptosis
  4. tachycardia
  5. hyperactive reflexes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the signs of Graves’ disease?

What clinical marker will be elevated?

A

the thyroid is diffusely enlarged

T3 and T4 will be elevated

TSH will be suppressed

There will be thyroid autoantibodies, especially thyroid stimulating immunoglobulin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is meant by multinodular goitre?

A

enlargement of the thyroid with varying degrees of nodularity

1 or more thyroid nodules discovered by a patient or health care provider

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the signs of multinodular goitre?

What may it be mistaken for?

A

most patients are euthyroid

the dominant nodule may be mistaken clinically for thyroid carcinoma

large nodules may cause tracheal compression or dysphagia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does euthyroid mean?

A

having a normally functioning thyroid gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is follicular adenoma? Who does it usually affect?
benign encapsulated tumour with evidence of follicular cell differentiation it affects more females there is a wide age range, usually from fifth to sixth decade
26
What are the symptoms of follicular adenoma? How is it usually detected?
painless neck mass, often present for years there is a solitary nodule involving only one lobe it is usually cold nodule on radioactive iodine imaging
27
What are the different types of malignant tumours of the thyroid?
* differentiated thyroid carcinoma * medullary carcinoma * anaplastic carcinoma * malignant lymphoma
28
What is the most commonest type of thyroid carcinoma? What people are most commonly affected?
papillary carcinoma female predominance is 2.5:1 it has a wide age range mean of 43 years
29
What is papillary carcinoma? What conditions is it associated with?
familial, autosomal dominant non-medullary thyroid carcinoma seen in FAP and Cowden's syndrome treated by therapeutic irradiation
30
What genetically causes papillary carcinoma?
activation of RET or NTRK1 this is caused by a variety of chromosomal translocations or inversions fusion of RET tyrosine kinase regions with constitutively expressed thyroid proteins BRAF V600E mutation RAS mutations
31
What is the macroscopic appearance of papillary carcinoma like?
* ill defined, infiltrative * some encapsulated * may be cystic * granular
32
33
What are the 5 different types of follicular neoplasms?
* follicular adenoma * minimally invasive follicular carcinoma * widely invasive follicular carcinoma * hurthle cell neoplasms * Ras mutations
34
WHat % of thyroid cancers are follicular carcinomas? How do patients present?
10-20% of all thyroid cancers 90% present with a solitary nodule in the thyroid 10% present with distant metastasis
35
What is the difference between a minimally invasive and widely invasive follicular carcinoma?
minimally invasive \< 5% metastasis widely invasive is \> 60% metastasis
36
What is Hurthle cell carcinoma? Who does it usually affect?
accounts for 3% of all differentiated thyroid carcinomas the median age is 53 (range of 24 - 85 years) sex ratio of F:M is 7 : 3
37
What is the clinical behaviour of Hurthle cell carcinoma? What are the most common haematogenous sites?
unlike follicular carcinoma there is a significant incidence of cervical lymph node metastases common haematogenous sites are bone, liver and lung
38
What is primary hyperparathyroidism?
excessive secretion of parathyroid hormone from one or more glands
39
What is meant by secondary hyperparathyroidism?
hyperplasia of glands with elevated PTH in response to hypocalcaemia this is from renal insufficiency, malabsorption or vitamin D deficiency
40
What is meant by tertiary hyperparathyroidism?
this occurs in association with longstanding secondary hyperparathyroidism
41
What is the incidence of primary hyperparathyroidism?
25-28 cases per 100,000 population Caucasian women over 60 - 190/100,000
42
What is the pathogenesis of primary hyperparathyroidism?
1. aging, tumorigenesis in general 2. association with ionising irradiation 3. MEN 2a
43
What is primary hyperparathyroidism associated with?
1. asymptomatic 2. arterial hypertension 3. psychiatric problems 4. hypercalcaemia 5. decreased renal function 6. osteoporosis 7. hyperparathyroid bone disease 8. hypercalcaemia symptoms 9. urolithiasis
44
What malignancies is primary hyperparathyroidism associated with?
1. single adenoma - 85-90% 2. diffuse chief or clear cell hyperplasia - 10-15% 3. carcinoma - 1%
45
What is parathyroid adenoma? How many people does it affect and how does it present?
an encapsulated benign neoplasm of parathyroid cells it affects 1 per 1000 people it presents with symptoms of hypercalcaemia
46
What is parathyroid adenoma associated with?
associated with MEN1 and MEN2 syndrome , hyperparathyroidism and jaw tumour syndrome it involves a single enlarged parathyroid gland all the other remaining glands are suppressed and small
47
What is secondary and tertiary hyperparathyroidism? In what patients is it common?
non-neoplastic increase in parathyroid parenchymal cell mass within all parathyroid tissue with a known stimulus it is common in patients with renal failure and on dialysis it has identical pathological features to primary hyperplasia and may be associated with massive gland enlargement
48
What is parathyroid carcinoma? What are the symptoms related to?
malignant tumour derived from parathyroid parenchymal cells symptoms are referable to excess calcium
49
How is parathyroid carcinoma treated? What is the survival like?
it is indolent with recurrences common (about 50% of cases) treated with surgery 50% of cases have 10-year survival
50
Label the adrenal gland
51
What is Cushing's syndrome?
a collection of signs and symptoms due to prolonged exposure to cortisol paraneoplastic Cushing's is seen in small cell lung carcinoma
52
What are the endogenous and exogenous causes of Cushing's syndrome?
**exogenous causes:** * excessive glucocorticoid medication **endogenous causes:** * adrenal cortical tumours * adrenal cortical hyperplasia * ACTH secreting pituitary adenoma
53
What are the signs and symptoms of Cushing's syndrome?
* hypertension * moon face * central obesity * buffalo hump * weak muscles * osteoporosis * insomnia * excessive sweating * mood swings * headaches * chronic fatigue Women may have increased hair growth (hirsuitism) and irregular menstruation
54
What is Conn's syndrome?
hyperaldosteronism - primary and secondary more common in women and those 30-50 years old excess production of the hormone aldosterone by the adrenal cortex leads to low renin levels this is controlled by the renin-angiotensin system
55
What are the symptoms and signs of Conn's syndrome?
* high blood pressure * headache * muscular weakness * muscle spasms * excessive urination * cardiac arrhythmias
56
What is the aetiology of Conn's syndrome?
aetiology includes adrenal cortical hyperplasia, adenoma and familial hyperaldosteronism
57
What is addison's disease?
primary adrenal cortical insufficiency caused by adrenal dysgenesis, adrenal destruction, autoimmune adrenalitis, tuberculosis secondary is due to failure of ACTH secretion
58
What are the symptoms of Addison's disease?
the autoimmune form is the most common triad of hyperpigmentation, postural hypotension and hyponatraemia
59
What is the treatment for Addison's disease?
treatment with long term steroid replacement it has a high mortality is it is not diagnosed
60
What is an adrenal cortical nodule? Who is more commonly affected?
a benign non-functional nodule of the adrenal cortex it affects between 1.5 and 3% of the population it is higher in elderly, hypotensive and diabetic patietns
61
What are the symptoms of adrenal cortical nodule? What is the treatment?
there are no clinical symptoms and it is an incidental discovery on radiographic studies no treatment is required
62
What is adrenal cortical adenoma? What is the incidence like?
benign neoplastic proliferation of adrenal cortical tissue symptoms are related to endocrine hyperfunction incidence between 1-5% of the population
63
What are the symptoms of adrenal cortical adenoma?
aldosterone prodicing tumours cause Conn's syndrome cortisol-producing tumours cause Cushing's syndrome rare tumours cause virilisation
64
What is adrenal cortical carcinoma?
a malignant counterpart of the adrenal cortical adenoma it accounts for 3% of endocrine neoplasms
65
What are the symptoms of adrenal cortical carcinoma? What is the prognosis like?
symptoms are related to hormone excess abdominal mass is present prognosis is age and state dependent 5-year survival rate is about 70%
66
WHat is phaeochromocytoma? What are the different types and causes?
catecholamine-secreting tumour arising from the adrenal medulla 10% are bilateral, 10% are extra-adrenal, 10% are malignant, 10% are familial and 10% are seen in children most cases are sporadic but familial syndromes MEN2a and 2b, von Recklinghausen's disease and vin Hippel-Lindau disease
67
What are the symptoms of phaeochromocytoma? What is prognosis like?
symptoms of hypertension, palpitation, headaches and anxiety elevated urine catecholamines, adrenaline and noradrenaline excellent prognosis when benign and properly managed surgically malignant tumour may pursue an aggressive course
68