Endocrinology only Flashcards
(230 cards)
1
Q
Give an example of a water-soluble hormone
A
Peptides
TRH, LH, FSH
2
Q
Are water-soluble hormones stored in vesicles or synthesized on demand?
A
Stored in vesicles
3
Q
How do water soluble hormones like peptides get into a cell?
A
Bind to cell surface receptors
4
Q
Give an example of a fat soluble hormone
A
Steroids, like cortisol
5
Q
Are fat-soluble hormones stored in vesicles or synthesized on demand?
A
Synthesised on demand
6
Q
Give an example of an amine hormone
A
Noradrenaline and adrenaline
7
Q
Describe the pathway for noradrenaline synthesis
A
Phenylalanine->L-tyrosine->L dopa->NAd and Ad
8
Q
Name 2 enzymes that break down catecholamines
A
MAO and COMT
9
Q
What are noradrenaline and adrenaline broken down into?
A
Normetadrenaline and metadrenaline
10
Q
Where in a cell are the peptide cell receptors located?
A
Located on the cell membrane
11
Q
Where in a cell are steroid cell receptors located?
A
Located in the cytoplasm
12
Q
Where in a cell are the thyroid/vitamin A and D cell receptors located?
A
Act on nuclear receptors
13
Q
Give 5 ways in which hormone action is controlled
A
- Hormone metabolism
- Hormone receptor induction
- Hormone receptor down-regulation
- Synergism, like glucagon and adrenaline
- Antagonism like glucagon and insulin
14
Q
What layer of the trilaminar disc is the anterior pituitary derived from?
A
Ectoderm-Rathke’s pouch
15
Q
Name 6 hormones produced by the anterior pituitary
A
- TSH
- FSH
- LH
- ACTH
- Prolactin
- GH
16
Q
What is the posterior pituitary derived from?
A
The floor of the ventricles
17
Q
Where are the posterior pituitary hormones synthesized?
A
Synthesized in the para-ventricular and supra-optic nuclei
18
Q
Name 2 hormones released from the posterior pituitary
A
- Oxytocin
- ADH
19
Q
What is the function of ADH?
A
Acts on the collecting ducts of the nephron and increases insertion of aquaporin 2 channels to increase H2O retention
20
Q
Give 2 functions of oxytocin
A
- Milk secretion
- Uterine contraction
21
Q
Which has a longer half-life: triiodothyronine or thyroxine?
A
Thyroxine: 5-7 days
Triiodothyronine: 1 day
22
Q
Describe the thyroid axis
A
Hypothalamus->TRH->AP->TSH->thyroid->T3 and T4
T3 and T4 have a negative feedback effect on the hypothalamus and anterior pituitary
23
Q
What would be the effect on TSH if you had an underactive thyroid?
A
TSH would be raised as you have less T3/T4 being produced so no negative feedback
24
Q
What would a low TSH tell you about the action of the thyroid?
A
Low TSH: over-active thyroid
Lots of T3 and T4 being produced so more negative feedback on the pituitary and less TSH
25
Describe the mechanism of action of ACTH
Hypothalamus->CRH->AP->ACTH->adrenal cortex (zona fasciculata)->glucocorticoid synthesis like cortisol
Cortisol has a negative feedback effect on the hypothalamus and the anterior pituitary
26
Give 3 functions of thyroid hormones (T3/T4)
1. Food metabolism
2. Protein synthesis
3, Increased sympathetic action like CO and HR
4. Heat production
5. Growth and development
27
Give 3 functions of cortisol in response to stress
1. Mobilises energy sources->lipolysis, gluconeogenesis, and protein breakdown
2. Vasoconstriction
3. Suppresses inflammatory and immune responses
4. inhibits non-essential functions like growth and reproduction
28
Briefly describe the mechanism of FSH and LH
Hypothalamus->GnRH->AP->FSH/LH->ovaries/testes
FSH acts on granulosa cells to produce oestrogen and Sertoli cells to stimulate spermatogenesis
LH acts on theca cells to produce androgens or Leydig cells to produce testosterone
29
What cells does FSH act on?
In the ovaries: granulosa cells
In the testes: sertoli cells
30
What cells does LH act on?
In the ovaries: theca cells
In the testes: leydig cells
31
What is the function of theca cells?
Stimulated by LH to produce androgens that diffuse into granulosa cells to be converted into oestrogen
32
What is the function of granulosa cells?
Stimulated by FSH to convert androgens into oestrogen using aromatose
33
What is the function of Sertoli cells?
Produce MIF(Mullerian inhibiting factor) and inhibin and activin which act on the pituitary gland to regulate FSH
34
What is the function of Leydig cells?
Stimulated by LH to produce testosterone
35
Describe the GH/IGF-1 axis
Hypothalamus->GHRH or SMS->AP->GH->liver->IGF-1
36
What is the function of IGF-1?
Induces cell division, cartilage and skeletal growth and protein synthesis
37
Briefly describe the mechanism of action of prolactin
Hypothalamus->dopamine->AP->prolactin
Prolactin acts on the mammary glands to produce milk
38
What would happen to serum prolactin levels if something was to impact on the pituitary stalk and block dopamine release?
Prolactin levels would increase
39
Give 3 potential consequences of a pituitary tumour
1. Pressure on local structures like an optic chiasm
Hypo-pituitary
Functioning tumours like in Cushing's, gigantism, prolactinoma
40
Give 2 causes of prolactinoma
1. Pituitary adenoma
2, Anti-dopaminergic drugs
41
Give 5 signs of prolactinoma
1. Infertility
2. Galactorrhea
3. Amenorrhoea
4. Loss of libido
5. Visual field defects due to local effect of the tumour
42
What investigation would you do on someone presenting with difficulty getting pregnant, galactorrhoea, amenorrhea, loss of libido and headaches?
Measure serum prolactin: symptoms of prolactinoma
43
Describe the treatment for prolactinoma
Dopamine agonist like cabergoline
44
Describe growth hormone secretion from the anterior pituitary
Secreted in a pulsatile fashion and increases during deep sleep
45
What can cause acromegaly?
Benign pituitary adenoma producing excess GH
46
Give 5 symptoms of acromegaly
1. Changes in appearance
2, increase in the size of hands and feet
3, Excessive sweating
4. Headache
5. Tiredness
6. Weight gain
7. Amenorrhoea
8. Deep voice
9. Goitre
47
Give 5 signs of acromegaly
1. Prognathism
2. Interdental separation
3. Large tongue
4. Spade-like hands and feet
5. Tight rings
6. Bi-temporal hemianopia
48
What co-morbidities are associated with acromegaly?
1. Arthritis
2. Cerebrovascular events
3. Hypertension and heart disease
4. Sleep apnea
5. T2DM
49
What investigations might you do on someone who you suspect has acromegaly?
1. Plasma GH-can exclude acromegaly
2. Serum IGF-1 levels-raised
3. Oral glucose tolerance test-diagnostic
4. MRI of pituitary
50
What test is diagnostic for acromegaly?
Oral glucose tolerance test-failure of glucose to suppress serum GH
51
Describe the treatment for acromegaly
1. Trans-sphenoidal surgical resection
2. Radiotherapy
3. Medical therapy: somatostatin analogues, dopamine agonists like cabergoline
52
Give 3 potential complications of trans-sphenoidal surgical resection for the treatment of acromegaly
1. Hypopituitarism
2. Diabetes insipidus
3. Haemorrhage
4. CNS injury
5. Meningitis
53
Give 3 advantages of using dopamine agonists in the treatment of acromegaly
1. No hypopituitarism
2. Oral administration
3. Rapid onset
54
Give 2 disadvantages of using dopamine agonists in the treatment of acromegaly
1. Can be ineffective
2. Risk of side effects
55
Name a dopamine agonist that can be used in the treatment of acromegaly
Cabergoline
56
Give 5 causes of hypothyroidism
1. Autoimmune thyroiditis like Hashimoto's thyroiditis and atrophic thyroiditis
2. Post-partum thyroiditis
3. Iatrogenic thyroidectomy
4. Drug-induced: carbimazole, amiodarone, lithium
Iodine deficiency
57
Name 3 antibodies that may be present in the serum of someone with autoimmune thyroiditis
1. TPO(thyroid peroxidase)
2. Thyroglobulin
3. TSH receptor
58
Give an example of a transient cause of hypothyroidism
Post-partum thyroiditis
59
Give 2 examples of iatrogenic causes of hypothyroidism
1. Thyroidectomy
2. Radioiodine therapy
60
Name 3 drugs that can cause hypothyroidism
1. Carbimazole
2. Amiodarone
3. Lithium
61
How can amiodarone cause hypo-hyperthyroidism
Because it is iodine rich
62
Give 5 symptoms of hypothyroidism
1. Menorrhagia: heavy bleeding
2. Obesity/weight gain
3. Malar flush
4. Fatigue
5. Cold intolerance
6. Eyebrow loss
7. Goitre
8. Depression
9. Dry skin/hair
63
Give 5 signs of hypothyroidism
1. Mental slowness
2. Dry, thin hair
3. Bradycardia
4. Anaemia
5. Hypertension
6. Loss of eyebrows
7. Cold peripheries
8. Carpal tunnel syndrome
64
What investigations might you do in someone you suspect has hypothyroidism?
-TFT's-serum TSH will be raised and T3/T4 will be low
-Thyroid antibodies
65
Describe the management for hypothyroidism
Levothyroxine
66
What is thyrotoxicosis?
Excess thyroid hormone due to any cause
67
Give 5 causes of thyrotoxicosis
1. Increased production like Grave's, toxic adenoma
2. Leakage of T3/T4 due to follicular damage
3. Ingestion
4. Thyroiditis
5. Drug induced
68
Give 2 causes of hyperthyroidism
1. Grave's disease
2. Toxic adenoma
69
Briefly describe the pathophysiology of Grave's disease
Autoimmune
TSH receptor antibodies stimulate thyroid hormone production->hyperthyroidism
70
Give 5 symptoms of Grave's disease that don't include ophthalmopathy signs
1. Weight loss
2. Increased appetite
3. Irritability
4. Tremors
5. Palpitations
6. Goitre
7. Diarrhoea
8. Heat intolerance
9. Malaise
10. Vomiting
71
Give 5 signs of Grave's disease that don't include ophthalmopathy signs
1. Tachycardia
2. Arrhythmias like AF
3. Warm peripheries
4. Muscle spasms
5. Pre-tibial myxoedema(raised purple lesions over the shins)
6. Thyroid acropachy (clubbing and swollen fingers)
72
With what disease would you associate pre-tibial myxoedema ad thyroid acropachy?
Grave's disease
73
Give 5 Grave's ophthalmopathy signs
1. Exophthalmos (bulging eyes)
2. Lid lag stare
3. Redness
4. Conjunctivitis
5. Pre-orbital edema
6. Bilateral
7. Extra-ocular muscle swelling
74
What investigations might you do in someone who you suspect has hypothyroidism?
TFT's: TSH suppressed and T3/T4 elevated
75
What would you see histologically in someone with Grave's disease?
Lymphocyte infiltration and thyroid follicle destruction
76
Describe the treatment for Grave's disease
1. Anti-thyroid drugs like carbimazole
2. Radioiodine drugs
3. Surgery-partial thyroidectomy
77
How does carbimazole work in treating Grave's disease?
Targets thyroid peroxidase so prevents the formation of T3/T4
78
Give a potentially serious side effect of taking carbimazole to treat Grave's disease
Agranulocytosis
79
What advice should you give a patient when prescribing carbimazole to treat Grave's disease
Seek medical attention if they develop an unexplained sore throat or fever-signs of agranulocytosis
80
How do radioiodine drugs work in treating Grave's disease?
Radioiodine drugs emit beta particles that destroy thyroid follicles so thyroid hormone production is decreased
81
Give 3 potential complications of a partial thyroidectomy
1. Bleeding
2. Hypocalcaemia
3. Hyporthyroidism
4. Recurrent laryngeal nerve palsy
82
What disease would you treat with carbimazole?
Grave's disease
83
What disease would you treat with levothyroxine?
Hypothyroidism
84
Give 5 metabolic changes that occur in pregnancy
1. Increased EPO, cortisol and NAd
2. High CO
3. High cholesterol and triglycerides
4. Pro thrombotic and inflammatory state
5. Insulin resistance
85
Give 5 gestational syndromes
1. Pre-eclampsia
2. Gestational diabetes
3. Obstetric cholestasis
4. Gestational thyrotoxicosis
5. Postnatal depression
6. Post partum thyroiditis
86
At what week are foetal thyroid follicles and T4 synthesised?
Week 10
87
Why can HCG activate TSH receptors and cause hyperthyroidism?
HCG and TSH are glycoprotein hormoens with very similar structures so HCG can activate TSH receptors
88
Is hypothyroidism or thyrotoxicosis more common in pregnancy?
Hypothyroidism more common
89
How can you differentiate between Grave's disease and gestational thyrotoxicosis?
Grave's: symptoms predate pregnancy and get more severe during pregnancy: goitre and TSH-R antibodies present
Gestational thyrotoxicosis: symptoms don't predate pregnancy, lots of N/V-hyperemesis gravidarum associated. No goitre or TSH-R
90
Give 3 potential consequences of untreated hypothyroidism in pregnancy
1. Gestational hypertension
2. Placenta abruption
3. Post partum haemorrhage
4. Low birth weight
5. Neonatal goitre
91
Give 3 potential consequences of untreated hyperthyroidism in pregnancy
1. Intra-uterine growth restriction
2. Low birth weight
3. Pre-eclampia
4. Risk of still birth/miscarriage
92
What is diabetes mellitus?
Disorder of carbohydrate metabolism characterised by hyperglycaemia
93
Which 4 cells make up the islets of Langerhans?
1. Beta cells (70%)
2. Alpha cells (20%)
3. Delta cells (8%)
4. Polypeptide secreting cells
94
What do beta cells produce?
Insulin
95
What do alpha cells produce?
Glucagon
96
What do delta cells produce?
Somatostatin
97
What is the importance of the alpha and beta cells being located next to each other in the islets of langerhans?
Enables them to 'cross talk'-insulin and glucagon show reciprocal action
98
Describe the mechanism of insulin secretion form beta cells
Glucose binds to beta cells->glucose 6 phosphate->ADP->ATP->K+ channels close->membrane depolarisation->Ca2+ channels open, influx->insulin release
99
Describe the physiological processes that occur in the fasting state in response to low blood glucose
Low blood glucose=high glucagon and low insulin
-Glycogenolysis and gluconeogenesis
-Reduced peripheral glucose uptake
-Stimulates the release of gluconeogenic precursors
Lipolysis and muscle breakdown
100
Describe the effect on insulin and glucagon secretion in the fasting state
Fasting state=low blood glucose
Raised glucagon and low insulin
101
How many carbon precursors are needed for gluconeogenesis?
3
102
Describe the physiological processes that occur after feeding in response to high blood glucose
High blood glucose = high insulin and low glucagon
-Glycogenolysis and gluconeogenesis are suppressed
-Glucose taken up by peripheral muscle and fat cells
-Lipolysis and muscle breakdown suppressed
103
Describe the effect on insulin and glucagon secretion after feeding
Insulin is high and glucagon is low
104
What would a persons fasting plasma glucose be if they were diabetic?
Fasting plasma glucose >7mmol/L
105
What would a persons random plasma glucose be if they were diabetic?
Random plasma glucose >11mmol/L
106
What would the results of the oral glucose tolerance test be if someone was diabetic?
Fasting plasma glucose >7mmol/L
2 hour value >11mmol/L
107
What would someones HbA1c be if they have diabetes?
>48mmol/mol
108
What is the effect of cortisol on insulin and glucagon?
Cortisol inhibits insulin and activates glucagon
109
Describe the aetiology of T1DM
Beta cells express HLA antigens
Autoimmune destruction->beta cells loss->impaired insulin secretion
110
Is T1DM characterized by a problem with insulin secretion, insulin resistance, or both?
Impaired insulin secretion-severe insulin deficiency
111
At what age do people with T1DM present?
Most often in childhood
112
Give 2 potential consequences of T1DM
1. Hyperglycaemia
2. Ketoacidosis
113
Describe the natural history of T1DM
Genetic predisposition + trigger->insulitis, beta cell injury->pre-diabetes->diabetes
114
Describe the pathophysiological consequence of impaired insulin secretion in T1DM
Severe insuline deficiency->glycogenolysis/gluconeogenesis/lipolysis all not suppressed and reduced peripheral glucose uptake->hyperglycaemia and glycosuria.
Perceived stress-?cortisol and Ad secretion-?catabolic state-?increased plasma ketones
115
Give 3 symptoms of T1DM
1. Weight loss
2. thirst (fluid and electrolyte losses)
3. polyuria (due to osmotic diuresis)
116
Is ketoacidosis associated with T1 or T2 dm?
Type 1-occurs due to absence of insulin
117
Describe the pathophysiology of DKA
No insulin->lipolysis->free fatty acids->oxidised in liver->ketone bodies and ketoacidosis
118
Name 3 ketone bodies
-Acetoacetate
-Acetone
-beta hydroxybutarate
119
Where does ketogenesis occur?
In the liver
120
Give 4 signs of DKA
1. Hypotension
2. Tachycardia
3. Kussmaul's respiration
4. Breath smells of ketones
5. Dehydration
121
Describe the treatment for T1DM
1. Education: make sure patient understands benefits of good glycaemic control
2. Healthy diet: low in sugar, high in carbohydrates
3. Regular activity, healthy BMI
4. BP and hyperlipidemia control
5. Insulin
122
How is insulin administered in someone with T1DM?
Injected into SC fat
123
Other than SC injections, how else can insulin be administered?
Insulin pump
124
Give 4 potential complications of insulin therapy
1. Hypoglycaemia
2. Lipohypertrophy at ejection site
3. Insulin resistance
4. Weight gain
5. Interference with life style
125
Is T2DM a problem with insulin secretion, resistance or both?
Impaired insulin secretion and insulin resistance
126
Describe the aetiology of T2DM
Genetic predisposition and environmental factors like obesity and lack of exercise
127
Why is insulin secretion impaired in T2DM?
Thought to be due to lipid deposition in the pancreatic islets
128
Describe the pathophysiology of T2DM
Impaired insulin secretion and resistance->IGT->T2DM->hyperglycaemia and high FFA's
129
Is insulin secretion or insulin resistance the driving force of hyperglycaemia in T2DM?
Hepatic insulin resistance is driving force of hyperglycaemia
130
Give 3 risk factors for insulin resistance in T2DM
1. Obesity
2. Physical inactivity
3. Family history
131
What happens to insulin resistance, insulin secretion and glucose levels in T2DM?
-Insulin resistance increases
-Insulin secretion decreases
-Fasting and post prandial glucose increase
132
Why do you rarely see DKA in T2DM
Insulin secretion is impaired but there are still low levels of plasma insulin. Even low levels of insulin can prevent muscle catabolism and ketogenesis
133
Describe the treatment pathway for T2DM
1. Lifestyle changes: lose weight, exercise, healthy diet
2. Metformin
3. Metformin + sulfonylurea
4. Metformin + sulfonylurea + insulin
5. Increase insulin dose as required
134
How does metformin work in treating T2DM?
Increases insulin sensitivity and inhibits glucose production
135
How does sulfonylurea work in treating T2DM?
Stimulates insulin release
136
Give a potential consequence of taking sulfonylurea for the treatment of T2DM
Hypoglycaemia
Sulfonylurea stimulates insulin release
137
Give 3 microvascular complications of diabetes mellitus
1. Diabetic retinopathy
2. Diabetic nephropathy
3. Diabetic peripheral neuropathy
138
Give a macrovascular complication of diabetes mellitus
CV disease and stroke
139
What is the main risk factor for diabetic complications?
Poor glycaemia control
140
Give a potential consequence of acute hyperglycemia
DKA and hyperosmolar coma
141
Give a potential consequence of chronic hyperglycemia.
Micro/macrovascular complications like diabetic retinopathy, nephropathy, neuropathy, CV disease etc
142
What is the commonest form of diabetic neuropathy?
Distal symmetrical polyneuropathy
143
Give 3 major consequences of diabetic neuropathy
1. Pain
2. Autonomic neuropathy
3. Insensitivity
144
Describe the pain associated with diabetic neuropathy
-Burning
-Paraesthesia
-Nocturnal exacerbation
145
What is autonomic neuropathy?
Damage to the nerves that supply body structures that regulate functions like BP, HR , bowel, bladder emptying
146
Give 5 signs of autonomic neuropathy
1. Hypotension
2. HR affected
3. Diarrhoea/constipation
4. Incontinence
5. Erectile dysfunction
6. Dry skin
147
What are the consequences of insensitivity as a result of diabetic neuropathy?
Insensitivity->foot ulceration->infection->amputation
148
Describe the distribution of insensitivity as a result of diabetic neuropathy
Insensitivity starts in the toes and moves proximally
Glove and stocking distribution
149
Give 5 risk factors for diabetic neuropathy
1. Poor glycaemic control
2. Hypertension
3. Smoking
4. HbA1c
5. Overweight
6. Long duration of DM
150
Describe the treatments for diabetic neuropathy
1. Improve glycaemic control
2. Antidepressants
3. Pain relief
151
PVD is a potential complication of diabetes. Give 6 signs of acute ischaemia
1. Pulseless
2. pale
3. perishing cold
4. Pain
5. paralysis
6. paraesthesia
152
Give 5 ways in which amputation can be avoided in someone with diabetic neuropathy
1. Screening for insensitivity
2. Education
3. MDT foot clinic
4. Pressure relieving footwear
5. Podiatry
6. Revascularisation and antibiotics
153
Would there be increased or decreased pulses in a diabetic neuropathic foot?
Increased foot pulses
154
Give 5 risk factors for diabetic retinopathy
1. Long duration DM
2. Poor glycaemic control
3. Hypertension
4. Insulin treatment
5. Pregnancy
6. High HbA1c
155
Describe the pathophysiology of diabetic retinopathy
Micro-aneurysms->pericyte loss and protein leakage->occlusion->ischaemia
156
How can diabetic retinopathy be sub-divided?
Can be divided into:
-Proliferative: evidence of neovascularization in the retina
-Non-proliferative
157
What would you see in someone with an R1 retinopathy grade?
R1-non-proliferative/background
-Micro-aneurysms
-Intraretinal haemorrhage
-Exudates
158
What would you see in someone with an R2 retinopathy grade?
R2-pre proliferative
-Venous bleeding
-Growth of new vessels
159
What would you see in someone with an R3 retinopathy grade?
R3-proliferative
-New blood vessel on disc
160
What is the treatment for diabetic retinopathy?
-Regular screening to assess visual acuity
-Laser therapy treats neovascularisation
161
What is the hallmark of diabetic nephropathy?
Development of proteinuria and progressive decline in renal function
162
What happens to the glomerular basement membrane in someone with diabetic nephropathy?
On microscopy there is thickening of the glomerular basement membrane
163
Give one way in which the presentation of diabetic nephropathy differs between T2 and T2DM
T1DM: microalbuminuria develops 5-10 year after diagnosis
T2DM: microalbuminuria often present at diagnosis
164
Describe the treatment for diabetic nephropathy
1. Glycaemia and BP control
2. ARB/ACEi
3. Proteinuria and cholesterol control
165
Name the suprasellar neoplasm that can result from benign cysts and calcification of Rathke's pouch?
Craniopharyngioma
166
Give 4 signs of craniopharyngioma
1. Raised ICP
2. Vision affected
3. Growth failure
4. Puberty affected
167
Give 4 local effects of pituitary adenoma
1. Headaches
2. Visual field defects-bitemporal hemianopia
3. CN palsy and temporal lobe epilepsy
4. CSF rhinorrhoea
168
What is the effect of hypothyroidism on TSH and T4 levels?
High TSH
Low T4
169
What is the affect of hyperthyroidism on TSH and T4 levels?
Low TSH
High T4
170
What is the affect of hypopituitarism on TSH and T4 levels?
Low TSH
Low T4
171
What is the treatment for thyroid hypopituitarism?
Levothyroxine
172
Give a cause of primary hypogonadism.
Klinefelter's syndrome-extra X chromosome
173
What is the effect of primary hypogonadism on testosterone and FSH/LH levels?
Testosterone will be low
FSH/LH will be low
174
What is the effect of hypopituitarism on testosterone and FSH/LH levels?
Low testosterone
Low FSH/LH
175
When should serum testosterone be measured?
At 9am due to circadian rhythm
176
Give 5 consequences of androgen deficiency in a male
1. Loss of libido
2. High pitched voice
3. Loss of facial, axillary, limb and pubic hair
4. loss of erection
5. Poorly developed scrotum and penis
177
What is the treatment for hypogonadism?
Testosterone gel/injection
Can improve BMD, QOL and libido etc
178
What syndrome is characterised by a congenital deficiency of GnRH
Kallmann's syndrome
179
Are the levels of oestradiol and FSH/LH low or high before puberty?
Before puberty: very low levels of these hormones in the serum
180
What is the effect of primary ovarian failure on oestradiol and FSH/LH levels?
FSH/LH high
Oestradiol is low
181
What is the effect of hypopituitarism on oestradiol and FSH/LH levels?
FSH/LH low
Oestradiol low
182
What is the effect of primary adrenal insufficiency on cortisol and ACTH levels?
Low cortisol
High ACTH
183
What is the effect of hypopituitarism on cortisol and ACTH levels?
Low cortisol
Low ACTH
184
What can lead to elevated levels of prolactin?
1. Stress
2. Drugs
3. Pressure on the pituitary stalk
185
What stimulates the posterior pituitary to release ADH?
Osmoreceptors in the hypothalamus detect raised plasma osmolarity->posterior pituitary is signalled to release ADH
186
Give 5 signs of diabetes insipidus
1. Excessive urine production (>3L/24hrs)
2. Very dilute urine <300mOsmol/kg
3. Severe thirst
4. Hypernatraemia
5. Dehydration
187
What investigations might you do to determine if someone has diabetes insipidus?
1. Measure 24 hr urine volume >3L/24 hr
2. Plasma biochemistry -hypernatraemia
Water deprivation test-urine won't concentrate when asked not to drink
188
What is the treatment for neurological diabetes insipidus?
Desmopression
189
Give 4 causes of polyuria
1. Hypokalaemia
2. Hypercalcaemia
3. Hyperglycaemia
4. Diabetes insipidus
190
Would TSH and T4 be high or low in someone with sub-clinical hypothyroidism?
High TSH but normal T4-often asymptomatic patients
191
What is Cushing's syndrome?
A set of signs/symptoms resulting from chronic glucocorticoid excess with a loss of normal feedback mechanisms
192
What can cause Cushing's syndrome?
1. Adrenal tumour (adenoma or carcinoma)
2. Pituitary tumour (Cushing's disease)
3. Exogenous steroids
4. Ectopic ACTH syndrome
193
What is Cushing's disease?
A set of signs/symptoms resulting from inappropriate ACTH secretion form the pituitary
ACTH dependent
194
Give 7 signs/symptoms of Cushing's disease
1. Central obesity
2. Moon face
3. Hypertension
4. Skin thinning
5. Abdominal striae
6. Mood changes
7. Osteoporosis
8. Muscle thinning
9. Weight gain
195
What investigations might you do in someone with Cushing's syndrome?
1. Overnight dexamethasone suppression test-failure to suppress cortisol
2. Late-night salivary cortisol -loss of circadian rhythm
3. Urinary free cortisol raised
4. Loss of circadian rhythm
196
What is the treatment for Cushing's syndrome
1. Surgical removal of pituitary tumours
2. Drugs to inhibit cortisol synthesis like metyrapone, ketoconazole
197
What is SIADH?
Syndrome of inappropriate ADH secretion
Too much ADH-very concentrated urine and hyponatraemia
198
Give 3 symptoms of SIADH
1. Anorexia
2. Nausea
3. Malaise
4. Headache
5. Confusion
199
Give 3 causes of SIADH
1. Malignancy
2, CNS disorders: meningitis, brain tumors, cerebral hemorrhages
3. TB
4. Pneumonia
5. Drugs
200
Describe the treatment for SIADH
1. Restrict fluid
2. Give salt
3. loop diuretics like furosemide
4. ADH-R antagonists like vaptans-useful when fluid restriction is challenging
201
What is Conn's syndrome?
Primary hyperaldosteronism-high aldosterone levels independent of RAAS activation->H2o sodium retention and potassium excretion
202
What are the 2 main signs of Conn's syndrome?
1. Hypertension
2. Hypokalaemia
Sodium will be normal or slightly raised
203
Give 3 symptoms of Conn's syndrome? Which electrolyte deficiency causes these symptoms?
1. Muscle weakness
2. Tiredness
3. Polyuria
Due to potassium deficiency-hypokalaemia
204
What can cause Conn's syndrome?
Adrenal adenoma
205
What hormone is raised in Conn's syndrome and what hormone is reduced? Where are these hormones synthesised?
1. Aldosterone is raised-synthesized in zona glomerulosa
2. Renin is reduced-synthesised by juxtaglomerular cells
206
What investigations might you do in someone to confirm a diagnosis of Conn's syndrome?
1. Bloods: U&E, renin (low) and aldosterone (high)
2. Plasma aldosterone renin ratio can be used as an initial screening test-raised result indicates the need for more tests
207
Give 4 ECG changes you might see in someone with Conn's syndrome
1. INcreased amplitude and width of P waves
2. Flat T waves
3. ST depression
4. Prolonged QT interval
5. U waves
208
What is the treatment for Conn's syndrome?
1. Laparoscopic adrenalectomy
2. Sprionolactone (aldosterone antagonist)
209
What does the parathyroid control?
Serum calcium levels
A low serum calcium triggers release of PTH and a high serum calcium triggers c-cells to release calcitonin
210
What hormone does the parathyroid secrete and what is its function?
PTH-secreted in response to low serum calcium
PTH increases bone resorption, increases calcium reabsorption at the kidney and activates vitamin D which then acts on the intestines to increase calcium absorption
211
What is released by c-cells in the parathyroid in response to high serum calcium?
Calcitonin
212
What is the effect of hyperparathyroidism on serum calcium levels?
Hyperparathyroidism->hypercalcaemia
213
Give 5 symptoms of hyperparathyroidism
Hyperparathyroidism->hypercalcaemia
1. Renal/biliary stones
2. Bone pain
3. Abdominal pain
4. Polyuria
5. Depression, anxiety, malaise
Stones, bones, groans, thrones, moans
214
Give 3 causes of hyperparathyroidism
1. Primary: parathyroid adenoma: high PTH, high calcium, low phosphate
2. Secondary: physiological hypertrophy in an attempt to correct low calcium
3. Prolonged uncorrected hypertrophy
215
Describe the treatment for hyperparathyroidism
1. High fluid intake, low calcium diet
2. Excision of adenoma
3. Correct the underlying cause
4. Parathyroidectomy
216
What is the effect of hypoparathyroidism on serum calcium levels?
Hypoparathyroidism->hypocalcaemia
217
Give 5 symptoms of hypoparathyroidism
Hypoparathyroidism->hypocalcaemia
1. Spasm
2. Paraesthesia around mouths and lips
3. Anxious and irritable
4. Seizures
5. Increased muscle tone
6. Confusion
7. Dermatitis
8. Impetigo herpetiformiis
9. QT prolongation
218
What is the treatment for hypoparathyroidism
Calcium supplements
219
Give 5 causes of hypocalcaemia
1. Dietary insufficiency
2. Anticonvulsant therapy
3. CKD
4. Vitamin D defieiceny
5. Osteomalacia
6. Hypoparathyroidism
220
Give 2 ECG changes that you might see in someone with hyperparathyroidism
Hyperparathyroidism->hypercalcaemia so:
-Tall T waves
-Shorted QT interval
221
Give 2 ECG changes that you might see in someone with hypoparathyroidism
Hypoparathyroidism->hypocalcaemia
-Small T waves
-Long QT interval
222
What is phaeochromocytoma?
A rare catecholamine secreting tumour in the adrenal medulla
223
Give 5 symptoms of phaeochromocytoma
Classic triad of:
-Headache
-Sweating
-Tachycardia
Also:
-Hypertension
-Palpitations
-Tremor
-Arrhythmia
-Confusion
224
What investigation might you do in order to diagnose someone with having a phaeochromocytoma
Bloods-raised WCC, increased plasma metadrenaline and normetadrenaline
225
What is the treatment for phaeochromocytoma?
1. Alpha blocker like phenoxybenzamine
2. Beta-blockers
3. Surgical resection of a tumour
226
What is the major concern in someone with pheochromocytoma?
Dangerous but treatable cause of hypertension
227
Describe the different types of SC insulins that can be given to people with T1DM
1. Ultra-fast acting like Humalog taken before eating in conjunction with long-acting insulin at night
2. Long-acting insulin like insulin glargine before going to bed
3. Pre-mixed insulin like NovoMix taken twice daily
228
What is adrenal insufficiency?
Adrenocortical insufficiency resulting in a reduction of a mineralocorticoids and glucocorticoids and androgens
229
Give 6 symptoms of adrenal insufficiency
1. Tanned pigmentation
2. Tired
3. Tearful
4. Thin-weight loss
5. Headaches
6. Abdominal cramps
7. Myalgia
8. Throwing up
9. Weakness
230
Give 5 primary causes of adrenal insufficiency
1. Addison's disease
2. Congenital adrenal hyperplasia
3. TB
4. Adrenal metastases
5. Drugs
6. Haemorrhage
7. Infection
