Endocrinology Lectures Flashcards
(156 cards)
1
Q
What BMI range is normal?
A
18.5 - 24.9
2
Q
What BMI range is overweight?
A
25.0 - 29.9
3
Q
What BMI range is obese?
A
30.0 - 39.9
4
Q
What BMI range is morbidly obese?
A
> 40
5
Q
List 7 risks of obesity.
A
1) type 2 diabetes
2) hypertension
3) coronary heart disease
4) stroke
5) osteoarthritis
6) obstructive sleep apnoea
7) cancer
6
Q
List 4 cancers linked to obesity.
A
1) breast
2) endometrium
3) prostate
4) colon
7
Q
What is appetite regulation a balance between?
A
Energy intake and energy expenditure.
8
Q
List 3 ‘organs’ that release hormones that regulate appetite.
A
1) brain
2) gastrointestinal tract
3) adipose tissue
9
Q
What part of the brain is crucial in appetite regulation?
A
Hypothalamus.
10
Q
Where is the hunger centre?
A
Lateral hypothalamus.
11
Q
Where is the satiety centre?
A
Ventromedial hypothalamic nucleus.
12
Q
List 4 hormones that affect appetite.
A
1) leptin
2) insulin
3) ghrelin
4) PYY
13
Q
What is the effect of leptin? (2)
A
1) decreases appetite
2) increases satiety
14
Q
What is the effect of insulin? (appetite) (2)
A
1) decreases appetite
2) increases satiety
15
Q
What is the effect of ghrelin? (2)
A
1) increases appetite
2) stimulates growth hormone release
16
Q
What is the effect of PYY? (2)
A
1) decreases appetite
2) inhibits gastric motility
17
Q
What is the pituitary gland close to?
A
Optic chiasm.
18
Q
How does the anterior pituitary receive blood?
A
Hypophyseal portal system —> from the hypothalamus.
19
Q
List the 6 pituitary hormones.
A
1) GH
2) TSH
3) ACTH
4) LH
5) FSH
6) PRL
20
Q
List 5 diseases of the pituitary gland.
A
1) pituitary adenoma - very common —> generally don’t present
2) craniopharygioma
3) traumatic brain injury
4) Sheehan’s syndrome
5) sarcoidosis - pituitary granulomas
21
Q
What is Sheehan’s syndrome.
A
Postpartum pituitary gland ischaemic necrosis.
22
Q
List 3 things pituitary tumours cause.
A
1) pressure on local structures
2) pressure on normal pituitary gland - hypopituitarism
3) functioning tumour
23
Q
Give an example of a local structure pressured by a pituitary tumour.
A
Optic chiasm, causing bitemporal hemianopia.
24
Q
List 3 conditions caused by a functioning pituitary tumour.
A
1) prolactinoma
2) acromegaly
3) Cushing’s disease
25
What is IGF-1?
Insulin-like growth factor 1. Anabolic hormone, carries out peripheral activity of GH.
26
Where is IGF-1 produced?
Liver.
27
What is glucose’s effect on GH?
Suppress GH secretion.
28
List 6 objectives of acromegaly treatment.
1) restore GH and IGF-1 to normal levels
2) relieve symptoms
3) reverse visual changes
4) reverse soft tissue changes
5) prevent further skeletal deformity
6) normalise pituitary function
29
List 3 therapeutic options for acromegaly.
1) pituitary surgery*
2) medical therapy
3) radiotherapy
30
List 3 types of medical therapy for acromegaly.
1) dopamine agonists
2) somatostatin analogues
3) GH receptor antagonists
31
What is cortisol function? (2)
Stress hormone.
1) stimulate gluconeogenesis
2) suppress immune system
32
What does cortisol circadian rhythm parallel?
Energy levels.
33
What is the time period of the circadian rhythm?
24.2 hours.
34
List 2 biochemical features that indicate adrenal insufficiency.
1) hyponatraemia
| 2) hyperkalaemia
35
Why are cortisol levels measured at 9:00 am?
Measures cortisol levels when they are at their highest.
36
What is the pharmaceutical name for cortisol?
Hydrocortisone.
37
Define adrenal crisis.
Medical emergency caused by severe cortisol insufficiency.
38
What happens in an adrenal crisis? (3)
1) hypotension
2) decreased organ perfusion
3) death
39
List 7 signs and symptoms of adrenal crisis.
1) shock
2) hypotension
3) hypoglycaemia
4) hyponatraemia
5) hyperkalaemia
6) fever
7) fatigue
40
What do you always immediately administer in adrenal crisis?
Hydrocortisone (if in doubt).
41
What is the prevalence of thyroid diseases in females compared to males?
5-10 times higher.
42
List 3 thyroid autoantibodies.
1) thyroid peroxidase
2) thyroglobulin
3) thyroid receptor
43
What is the main mechanism of thyroid autoimmunity.
Cytotoxic T cell mediated.
44
List 2 genetic factors increasing risk of thyroid autoimmunity.
1) female
| 2) HLA-DR3
45
List 4 environmental factors increasing risk of thyroid autoimmunity.
1) postpartum
2) stress
3) smoking
4) high iodine intake
46
List 8 autoimmune diseases associated with thyroid autoimmunity.
1) type 1 diabetes
2) Addison’s disease
3) pernicious anaemia
4) vitiligo
5) alopecia areata
6) coeliac disease
7) rheumatoid arthritis
8) myasthenia gravis
47
What is the cause of thyroid autoimmunity associated ophthalmopathy? (3)
1) extraocular muscle autoantigen identical to thyroid autoantigen
2) thyroid autoantibody reacts with extraocular muscle autoantigen
3) extraocular muscle swelling
48
Define goitre.
Palpable and visible thyroid enlargement.
49
List 4 types of goitre.
1) diffuse
2) solitary nodule
3) multinodular
4) dominant nodule
50
List the 3 mechanisms causing hyperthyroidism.
1) excessive T3/T4 production
2) leakage of preformed T3/T4
3) excessive T3/T4 ingestion
51
How does iodine 131 work as hyperthyroidism treatment? (4)
1) α particle emission
2) thyroid cells ionise
3) direct damage to DNA and enzymes
4) indirect damage via free radicals
52
What is the main type of hypothyroidism.
Primary hypothyroidism (99%).
53
List 3 hormones that affect serum calcium and their effect.
1) PTH —> increase serum calcium
2) calcitriol —> increase serum calcium
3) calcitonin —> decrease serum calcium
54
List 3 reasons why calcium is important.
1) calcification in ossification (bone formation)
2) nerve functioning
3) muscle functioning
55
Define corrected calcium.
Measure of serum calcium that accounts for albumin bound calcium.
56
Corrected calcium formula.
corrected calcium = total serum calcium + 0.02 x (40 - serum albumin)
57
What is Chvostek’s sign? (3)
1) sign of hypocalcaemia
2) tap facial nerve (near external carotid artery)
3) facial muscle spasm
58
What is Trousseau’s sign? (3)
1) sign of hypocalcaemia
2) inflate blood pressure cuff 20mmHg above systolic for 5 minutes
3) hand muscle spasm - claw
59
What is the characteristic sign of pseudohypoparathyroidism?
Short 4th and 5th metacarpals.
60
List 2 things that can mimic hypercalcaemia.
1) tourniquet on for too long
| 2) old, haemolysed blood sample
61
Define puberty.
Physiological, morphological and behavioural changes when gonads develop into adult form.
62
What is the definitive sign of puberty in females?
Menarche - first menstruation.
63
What is the definitive sign of puberty in males?
First ejaculation.
64
Define secondary sexual characteristics.
Features that develop in puberty.
65
List 4 female secondary sexual characteristics.
1) uterus and vagina growth
2) pubic hair growth
3) breast growth
4) wider hips
66
List 4 male secondary sexual characteristics.
1) penis grows
2) pubic hair growth
3) larynx and laryngeal muscles enlarge - voice breaks
4) musclier body
67
What testes size is pre-pubertal? (2)
1) volume < 3ml
| 2) diameter < 2.5cm
68
What is the first ‘visible’ female change in puberty.
Breast development - breast bud.
69
List 3 effects of oestrogen on the breast.
1) ducal proliferation
2) adipose deposition
3) areola and nipple enlargement
70
List 4 hormones involved in breast development.
1) oestrogen - majority
2) prolactin
3) glucocorticoids - cortisol
4) insulin
71
Define precocious puberty.
Onset of secondary sexual characteristics before 8 years in females and 9 years in males.
72
Define delayed puberty.
Absence of secondary sexual characteristics by 14 years in females and 16 years in males.
73
List 2 complications of delayed puberty.
1) reduced peak bone mass
| 2) osteoporosis
74
Define adrenarche.
Maturation of the adrenal glands resulting in the formation of the zona reticularis.
75
List 4 features of adrenarche.
1) axillary hair
2) oily skin
3) mild acne
4) body odour
76
Describe body water distribution. (4)
1) intracellular fluid - 28L
2) extracellular fluid - 14L
3) interstitial fluid - 11L (ECF)
4) intravascular fluid - 3L (ECF)
77
List 2 responses to low plasma osmolality.
1) decrease thirst
| 2) decrease ADH secretion
78
List 2 responses to high plasma osmolality.
1) increase thirst
| 2) increase ADH secretion
79
List the 3 ADH receptors, their location and function.
1) V1a - vasculature - vasoconstriction
2) V1b - pituitary gland - ACTH release
3) V2 - renal collecting duct - water reabsorption
80
List 2 main determinants of osmolality.
1) total body water
| 2) serum sodium
81
Formula for calculated osmolality.
calculated osmolality = glucose + urea + 2 x sodium
82
What is the normal osmolality range?
282 mmol/l - 295 mmol/l
83
What is the limiting factor of plasma osmolality? (2)
urine osmolality
1) cannot increase beyond 1200mOsmol/kg
2) irrespective of ADH
84
What is hyponatraemia range?
Serum sodium < 135mmol/l.
85
What is the severe hyponatraemia range?
Serum sodium < 125mmol/l.
86
What is the mortality of hyponatraemia and it’s caveat?
1 in 3. Generally due to underlying cause.
87
List the order of checking SIADH causes. (4)
1) drugs
2) respiratory
3) central nervous system
4) tumours
88
What is the most common intracranial tumour.
Pituitary adenoma.
89
What percentage of non-functioning pituitary adenomas are incidenalomas?
50%
90
List 3 reasons why testing pituitary function is complex.
1) many hormones
2) may have borderline deficiencies
3) pulsatile and affected circadian rhythm
91
What should diabetes mellitus be thought of as?
A vascular disease.
92
Which form of diabetes mellitus has a higher genetic component? (2)
Type 2.
1) type 1 - 30% concordance in twins
2) type 2 - 80% concordance in twins
93
2 out which 3 features indicate type 1 diabetes mellitus and immediate insulin treatment? (3)
1) weight loss
2) high ketones (blood or urine)
3) short history of hyperglycaemic symptoms (week)
94
List 3 reasons differentiating type 1 and type 2 diabetes mellitus is hard.
1) type 1 patients can be obese
2) type 2 patients can be young
3) uncontrolled type 2 can present with weight loss and ketouria
95
What geographical parameter increases risk of type 1 diabetes mellitus?
Distance from equator.
96
List 4 antibodies associated with type 1 diabetes.
1) pancreatic islet cell
2) islet antigen 2
3) zinc transporter 8
4) glutamic acid decarboxylase
97
Describe the onset of diabetic ketoacidosis. (8)
1) decreased insulin secretion / decreased insulin efficacy
2) decreased cellular glucose uptake
3) hyperglycaemia
4) increased lipolysis
5) increased free fatty acids
6) increased hepatic fatty acid metabolism
7) increased plasma ketone bodies
8) decreased plasma pH
98
List the 3 main features of diabetic ketoacidosis.
1) hyperglycaemia
2) ketones
3) acidosis
99
List 2 things type 1 diabetes mellitus patients should aware of during insulin treatment.
1) carbohydrate intake
| 2) exercise
100
List the 5 stages of hypoglycaemia.
1) 4.6mM - inhibition of insulin secretion
2) 3.8mM - glucagon and adrenaline secretion
3) 3.8-2.8mM - autonomic symptoms
4) < 2.8mM - neuroglycopenic symptoms
5) < 1.5mM - severe neuroglycopenic
101
List 3 autonomic symptoms of hypoglycaemia.
1) sweating
2) tremor
3) palpitations
102
List 5 neuroglycopenic symptoms of hypoglycaemia.
1) confusion
2) drowsiness
3) altered behaviour
4) speech difficulty
5) incoordination
103
List 2 severe neuroglycopenic symptoms of hypoglycaemia.
1) convulsions
| 2) coma
104
What is dilemma for type 1 diabetes mellitus patients?
Balancing hypoglycaemia symptoms against diabetic complications.
105
List 4 factors making type 1 diabetes mellitus self-management hard.
1) difficulty
2) hypoglycaemia
3) lifestyle interference
4) lack of training
106
List 4 other causes of diabetes mellitus.
1) monogenic
2) exocrine pancreas pathology
3) endocrine pathology
4) drug induced
107
List 3 mechanisms by which diabetes mellitus causes morbidity and mortality.
1) acute hyperglycaemia —> diabetic ketoacidosis and hyperosmolar coma
2) chronic hyperglycaemia —> tissue complications
3) hypoglycaemia (treatment side effects)
108
List 3 clinical consequences of diabetic neuropathy.
1) pain, e.g. burning and paraesthesia
2) autonomic pathology, e.g. incontinence or erectile dysfunction
3) insensitivity - numbness
109
What is the pattern of sensory loss in diabetic neuropathy?
Glove and stocking.
110
List the 2 causes of a diabetic foot amputation.
1) neuropathy —> decreased sensation
| 2) vascular disease —> decreased perfusion
111
List 4 signs of diabetic vascular disease.
1) decreased/absent pedal pulse
2) cold feet and toes
3) poor skin and nails
4) absence of hair on feet and legs
112
List 5 ways to decrease diabetic amputation.
1) screening
2) education
3) orthotic shoes
4) MDT feet clinics
5) revascularisation
113
What is the most common cause of end stage renal disease?
Diabetic nephropathy.
114
List 4 modifiable risk factors for diabetes mellitus complications.
1) blood glucose
2) blood pressure
3) smoking
4) high cholesterol
115
Where does ingested glucose go? (2)
1) peripheries (e.g. muscles) - 60%
| 2) liver - 40%
116
List 5 effects of insulin.
1) decreased hepatic glycogenolysis
2) decreased hepatic gluconeogenesis
3) increased glucose uptake in insulin sensitive tissues (fat and muscle)
4) decreased lipolysis
5) decreased muscle breakdown
117
List 5 effects of glucagon.
1) increased hepatic glycogenolysis
2) increased hepatic gluconeogenesis
3) decreased glucose uptake in peripheries
4) increased lipolysis
5) increased muscle breakdown
118
At a cellular level when is the clinical onset of type 1 diabetes mellitus?
10% of β cells remain.
119
Why doesn’t type 2 diabetes mellitus generally lead to diabetic ketoacidosis?
Low insulin levels prevent ketogenesis.
120
What are the hypoglycaemia classifications? (3)
1) level 1 - no symptoms alert value, plasma glucose < 3.9mM
2) level 2 - mild symptoms, plasma glucose < 3.0mM
3) level 3 - severe symptoms, plasma glucose < 3.0mM
121
What is the distinction between mild and severe hypoglycaemia? (2)
1) mild hypoglycaemia - self-treatable
| 2) severe hypoglycaemia - require help
122
What is the average number of severe hypoglycaemic episode for a patient in a year?
1.
123
List 6 risk factors for severe hypoglycaemia in type 1 diabetes mellitus patients.
1) HbA1c < 48mmol/mol
2) history of severe episodes
3) long duration
4) extreme ages
5) renal impairment
6) impaired awareness of hypoglycaemia
124
List 6 risk factors for severe hypoglycaemia in type 2 diabetes mellitus patients.
1) aggressive treatment
2) long duration of insulin therapy
3) old age
4) cognitive impairment
5) renal impairment
6) impaired awareness of hypoglycaemia
125
How do you treat hypoglycaemia? (6)
1) recognise symptoms
2) check blood glucose (alert value < 3.9mM)
3) 15g fast-acting carbohydrate - relieve symptoms
4) recheck blood glucose (> 4.0mM)
5) 15g fast-acting carbohydrate - if < 4.0mM
6) long acting carbohydrate - prevent recurrence of symptoms
126
List 4 ways medications for type 2 diabetes mellitus work.
1) replace - insulin injections
2) secrete - increase insulin secretion
3) sensitise - increase response to insulin
4) excrete - decrease renal reabsorption of glucose
127
List 3 type 2 diabetes mellitus drugs that work by increasing insulin secretion.
1) sulphonylurea
2) DDP-4 inhibitors
3) GLP-1 receptor agonists
128
List 2 type 2 diabetes drugs that work by increasing response to insulin.
1) metformin
| 2) pioglitazone
129
What type 2 diabetes mellitus drugs works by decreasing renal reabsorption of glucose?
SGLT2 inhibitors.
130
What is the first drug prescribed for type 2 diabetes mellitus?
Metformin.
131
What fasting blood glucose does basal insulin aim to achieve?
5mM - 7mM.
132
What type of basal insulin is better and why? (2)
1) synthetic basal analogues are better than human basal analogues
2) steady insulin action - no peak
133
What is the best insulin treatment for type 1 diabetes mellitus?
Basal-bolus insulin therapy.
134
Describe management progression of type 2 diabetes mellitus. (5)
1) lifestyle changes
2) metformin
3) add one of pioglitazone, suphonylurea, DPP-4 inhibitor, GLP-1 receptor agonist, SGLT2 inhibitor
4) add another one of pioglitazone, suphonylurea, DPP-4 inhibitor, GLP-1 receptor agonist, SGLT2 inhibitor
5) insulin therapy
135
What effect does metformin have on weight?
Weight loss.
136
What effect does sulphonylurea have on weight?
Weight gain.
137
What effect do DPP4 inhibitors have on weight?
No effect.
138
What effect does plioglitazone have on weight?
Weight gain.
139
What age does pseudoparathyroidism generally present in?
Childhood.
140
What condition is associated with Albright hereditary osteodystrophy?
Pseudoparathyroidism.
141
List 3 features of Albright’s hereditary osteodystrophy.
1) short 4th and 5th metacarpals
2) round face
3) short stature
142
What percent of hypercalcaemia is caused by either malignancy or primary hyperparathyroidism
90%.
143
List 5 causes of hypocalcaemia with elevated serum phosphates.
1) chronic renal failure
2) hypoparathyroidism
3) pseudoparathyroidism
4) parathyroidectomy
5) thyroidectomy
144
List 3 causes of hypocalcaemia with low serum phosphate.
1) acute pancreatitis
2) vitamin D deficiency
3) osteomalacia
145
How do NSAIDs treat nephrogenic diabetes insipidus? (4)
1) NSAIDs inhibit prostaglandin synthase
2) decreased prostaglandin inhibition of ADH action
3) increased water retention
4) decreased urine production
146
List 2 common places to develop hypernatraemia.
1) hospital
| 2) care home
147
What is the HbA1c target range for type 1 diabetes mellitus?
48-55.
148
What is the myocardial infarction risk increase for diabetics?
X4.
149
What is the stroke risk increase for diabetics?
X2.
150
List the 2 methods of antithyroid drug administration.
1) block and replace
| 2) titrate
151
What method of antithyroid drug administration is preferred and why?
Block and replace, less likely to progress to hypothyroidism.
152
What is the difference between hyperthyroidism and thyrotoxicosis? (2)
1) hyperthyroidism —> excess thyroid stimulation
| 2) thyrotoxicosis —> excess T3/T4 in blood
153
What term is used to describe sever hypothyroidism?
Myxoedema coma.
154
List 5 features of a myxoedema coma.
1) hypothermia
2) hypoventilation
3) hyponatraemia
4) hypoglycaemia
5) heart failure
155
List 7 features of a thyroid storm.
1) hyperpyrexia
2) tachycardia
3) jaundice
4) diarrhoea
5) vomiting
6) confusion
7) coma
156
List the 4 stages of diabetic retinopathy.
1) preproliferative retinopathy
2) proliferative retinopathy
3) maculopathy
4) cataracts
