Endocrinology Flashcards
1
Q
Diabetes Mellitus Type 1
A
Autoimmune destruction of pancreatic beta cells leading to complete insulin deficiency
2
Q
Diabetes Mellitus Type 2
A
Combination of peripheral insulin resistance and less severe insulin deficiency
3
Q
Diabetic Ketoacidosis
A
A state of uncontrolled catabolism associated with insulin deficiency
4
Q
Hyperosmolar Hyperglycaemic State
A
A combination of diabetes mellitus with high blood sugar levels to high osmolarity without significant ketoacidosis
5
Q
Hyperthyroidism
A
Overactivity of the thyroid gland leading to excess thyroid hormones
6
Q
Hypothyroidism
A
Underactivity of thyroid gland leading to deficiency of thyroid hormones
7
Q
Grave’s Disease
A
Autoimmune disorder characterised by autoantibodies to TSH- receptor and is the leading cause of hyperthyroidism
8
Q
Hashimoto’s Thyroiditis
A
Chronic autoimmune thyroiditis which is the leading cause of hypothyroidism
9
Q
Thyroid Cancer
A
Malignant neoplasm of the thyroid gland
10
Q
Cushing’s Syndrome
A
Chronic excess of cortisol hormone released by adrenal glands leading to symptoms due to prolonged exposure
11
Q
Acromegaly
A
Excessive production of growth hormone occurring in adults after fusion of the epiphyseal plates
12
Q
Conn’s Syndrome
A
Excess aldosterone due to autonomous overproduction that is independent of the renin-angiotensin 2 system = PRIMARY HYPERALDOSTERONISM
13
Q
Pituitary Adenoma
A
Benign tumours that often arise sporadically in the anterior pituitary gland
14
Q
Addison’s Disease
A
Primary adrenal insufficiency due to inability of adrenal glands to produce enough steroid hormones
15
Q
Secondary Adrenal Insufficiency
A
Inadequate stimulation of adrenal cortex by the pituitary or hypothalamus
16
Q
SIADH
A
Syndrome of inappropriate ADH secretion is caused by increased ADH secretion from the pituitary gland despite a normal plasma volume, causing the body to retain too much water.
17
Q
Hyperkalaemia
A
High serum potassium over 5.5mmol/L
18
Q
Hypokalaemia
A
Low serum potassium under 3.5mmol/L
19
Q
Diabetes Insipidus
A
Passage of large volumes of dilute urine causing rapid dehydration
20
Q
Hypercalcaemia
A
High calcium levels over 10.5mg/dL in blood serum
21
Q
Hypocalcaemia
A
Low calcium levels under 8.5mg/dL in blood serum
22
Q
Thyroid Storm
A
An acute, life threatening, hyper metabolic state induced by excessive release of thyroid hormones - Acute exacerbation of hyperthyroidism
23
Q
Hyperparathyroidism
A
Abnormally high PTH levels in the blood due to overactivity of the parathyroid glands
24
Q
Hypoparathyroidism
A
RARE disorder of low PTH levels due to under activity of the parathyroid glands
25
Neuroendocrine Tumour
Carcinoid tumours are the most common
| Small, slow growing tumours synthesising a variety of hormones (especially serotonin)
26
Pheochromocytoma
Adrenal medullary tumour that secretes catecholamine
27
Prolactinoma
An adenoma of the anterior pituitary gland causing increased production of prolactin
28
DM Type 1 signs & symptoms
- polydipsia
- polyuria
- weight loss
USUALLY SHORT HISTORY OF SEVERE SYMPTOMS
29
DM Type 1 diagnosis
- young
- BMI < 25
- signs and symptoms
- personal or FHx of autoimmune disease
- random plasma glucose > 11mmol/L
30
DM Type 1 pathophysiology
- Autoimmune destruction of beta cells in Islets of Langerhans by autoantibodies
- insulin deficiency and continued breakdown of liver glycogen
- Muscles/tissues think they are starving
31
DM Type 1 treatment
INSULIN
32
DM Type 2 pathophysiology
- Insulin resistance due to B cell dysfunction
| - Beta cell hypertrophy and hyperplasia result in more insulin in order to remove glucose from blood
33
DM Type 2 signs and symptoms
- ASYMPTOMATIC
- develop signs of hyperglycaemia if severe (polyuria and polydipsia)
- glycosuria
- central obesity
- slow onset
34
DM Type 2 diagnosis
- HbA1C test
- blood glucose test
- random higher than 11.1 mol/L
35
DM Type 2 treatment
- lifestyle modification
- 1st line therapy = metformin
- 2nd line = dual therapy
36
DKA pathophysiology
- complete absence of insulin leads to unrestrained increased hepatic gluconeogenesis
- hyperglycaemia caused
- osmotic diuresis in kidneys causing dehydration
- peripheral lipolysis increases FFA and these are oxidised to ketones in liver
- LEADS TO METABOLIC ACIDOSIS
37
DKA characterised triad
- hyperglycaemia
- raised plasma ketones
- metabolic acidosis
38
DKA signs
- reduced tissue turgor
- Kussmaul's breathing - deep and rapid
- fruity breath
- hypotension
- tachycardia
39
DKA symptoms
- diabetes symptoms
- nausea and vomiting
- weight loss
- drowsy/confused
- abdominal pain
- sunken eyes/dry tongue
- dehydration
40
DKA diagnosis
- random plasma glucose > 11.1mmol/L
- plasma ketones > 3mmol/L
- pH < 7.35
- bicarbonate < 15mmol/L
- urine dipstick shows glycosuria and ketouria
- U&E often raised when dehydrated
41
DKA treatment
- ABC
- fluid replacement
- IV insulin
- restore electrolytes
42
DKA complications
- coma
- cerebral oedema
- thromboembolism
- aspiration pneumonia
- death
43
Hyperosmolar hyperglycaemic state pathophysiology
Decreased insulin levels insufficient to inhibit hepatic glucose production but sufficient to inhibit hepatic ketogenesis
44
HHS signs and symptoms
- decreased levels of conciousness
- severe dehydration
- hyperglycaemia
- hyperosmolality
- no ketones in blood/urine
45
HHS diagnosis
- random plasma glucose > 11mmol/L
- urine dipstick = glycosuria
- high plasma osmolality
46
HHS treatment
- same as DKA
- fluid replacement
- LMWH - reduce thromboembolism risk
- restore electrolytes
- insulin if severe
47
Hyperthyroidism pathophysiology
```
PRIMARY = excess T3/4 production from thyroid leads to compensatory decrease of TSH secretion
SECONDARY = excess TSH secretion from pituitary leads to excess T3/4 production from thyroid (RARE)
```
48
Hyperthyroidism signs and symptoms
- weight loss despite increased appetite
- palpitations
- tachycardia
- tremor
- diarrhoea
- anxiety/agitation
- sweaty skin
- heat intolerance
- proximal muscle weakness
- oligomenorrhoea
49
Hyperthyroidism diagnosis
- identify cause
- check thyroid antibodies (Graves)
- look for goitre/nodules
- radioactive iodine uptake test (RAIU) - greater uptake in Graves
- thyroid function tests
PRIMARY = low TSH, high T3/4
SECONDARY = high TSH, high T3/4
50
Hyperthyroidism treatment
- B blockers decrease somatic nervous system action
- Carbimazole = antithyroid drug
- Radioiodine therapy - destruction of thyroid tissue
- Thyroidectomy
51
Hypothyroidism pathophysiology
- PRIMARY = insufficient thyroid hormone production from the thyroid gland
- SECONDARY = insufficient TSH production from pituitary gland (RARE)
52
Most common causes of hypothyroidism in developed and developing countries
```
Developed = Hashimoto's thyroiditis
Developing = iodine deficiency
```
53
Hypothyroidism signs
- bradycardia
- slow reflexes
- ataxia
- cold peripheries
- ascites
- round, puffy face
54
Hypothyroidism symptoms
- hoarse voice
- goitre
- weight gain
- constipation
- cold intolerance
- menorrhagia
- tiredness
- lethargy
55
Hypothyroidism diagnosis
- TFT
PRIMARY = high TSH, low T3/4
SECONDARY = low TSH, low T3/4
- thyroid antibodies - TPO in Hashimoto's
56
Hypothyroidism treatment
- lifelong oral levothyroxine (T4)
57
Grave's disease pathophysiology
- Beta cells produce IgG antibodies against TSH receptor
- stimulating antibodies cause stimulation of thyroid gland to release T3/4
- leads to increased thyroid function and thyroid hyperplasia (goiter)
58
Graves triad
- hyperthyroidism
- pretibial myxedema
- opthalmopathy
59
Grave's signs and symptoms
- diffuse, smooth goiter
| - hyperthyroidism symptoms
60
Grave's diagnosis
- usually apparent on clinical examination
- detecting TSH receptor antibodies
- TFTs = low TSH, high T3/4
61
Grave's treatment
- beta blockers to control symptoms
- Carbimazole or propylthiouracil (PTU)
- radioactive iodine therapy
62
Hashimoto's pathophysiology
- B lymphocytes produce antibodies against TPO and thyroglobulin
- autoimmune destruction causes inflammation and therefore eventual destruction of gland
63
Hashimoto's signs and symptoms
- hypothyroidism symptoms
| NON TENDER, PAINLESS RUBBERY GOITER WITH SYMMETRICAL ENLARGEMENT
64
Hashimoto's diagnosis
- TFTs = high TSH, low T3/4
- antibody screen
anti-TPO antibody = positive
anti- Tg antibody = positive
65
Hashimoto's treatment
- levothyroxine for moderate/severe (synthetic T4)
| - monitor if mild
66
Thyroid cancer types
- Papillary carcinoma
- follicular carcinoma
- anaplastic carcinoma
- medullary carcinoma
67
Well differentiated thyroid cancers
- papillary
| - follicular
68
Poorly differentiated thyroid cancers
- medullary
| - anaplastic
69
Thyroid cancers affecting thyrocytes
- follicular
- anaplastic
- papillary
70
Thyroid cancer affecting parafollicular cells
- medullary
71
Thyroid cancer signs and symptoms
- asymptomatic nodule
- firm and painless nodule
- neck lymph nodes may be swollen
- tracheal deviation potentially present
- late stage = dysphagia, hoarseness
72
Thyroid cancer diagnosis
- normal TSH level
- Ultrasound shows nodular with irregular margins
- Tumour markers
thyroglobulin or calcitonin (in medullary)
73
Thyroid cancer treatment
- surgery
- followed by radioactive iodine ablation
- TSH suppression with levothyroxine
74
Thyroid cancer prognosis
- almost 100% 5y survival rate for thyrocyte cancers that are well differentiated
- very poor prognosis (30% 5ySR) for localised anaplastic
75
Cushing's pathophysiology
ACTH dependent - excessive ACTH secretion by pituitary gland
| ACTH independent - adrenal adenomas causing excess cortisol production
76
Cushing's signs and symptoms
- central obesity
- plethoric complexion
- moon face
- stretchmarks
- osteoporosis
- diabetes/insulin resistance
- thin skin
- easy bruising
77
Cushing's diagnosis
- drug history (mainly caused by oral steroids)
- random plasma cortisol screening
- 24hr urinary free cortisol levels
- overnight dexamethasone suppression test
- test plasma ACTH
78
Cushing's treatment
- dependent on cause
- pituitary adenoma = transsphenoidal surgical resection
- adrenal adenoma = adrenalectomy
79
Acromegaly pathophysiology
- too much GH excreted due to pituitary adenoma
- GH travels to tissues such as liver causing increase in IGF-1
- stimulates skeletal muscle and soft tissue growth
80
Acromegaly signs
- acral enlargement
- big tongue
- prominent supraorbital ridge
- puffy lips, eyes, skin
- obstructive sleep apnoea
- hypertension
- insulin resistance
81
Acromegaly symptoms
- headaches
- bitemporal hemianopia
- hypopituitarism
- sweating
- decreased libido
- amenorrhoea
- galactorrhoea
82
Acromegaly diagnosis
- serum IGF-1 levels (raised)
- oral glucose tolerance test (GH remains high)
- changes in ring/shoe size
- MRI of pituitary fossa
83
Acromegaly treatment
- transsphenoidal surgical resection
| - Medical therapy (somatostatin analogues or dopamine agonists)
84
Conn's pathophysiology
- excess aldosterone produced
- increased Na+ resorption and K+ secretion
- hypertension and potential hypokalaemia
85
Conn's signs and symptoms
- hypertension
- hypokalaemia
- mood disturbance
- difficulty concentrating
- polyuria and polydipsia
86
Conn's diagnosis
- low plasma potassium
- high aldosterone/renin ratio
- CT/MRI of adrenal glands - looking for adenomas/hyperplasia
- selective adrenal venous sampling (G Standard)
87
Conn's treatment
- benign tumour = unilateral adrenalectomy
| - bilateral hyperplasia = aldosterone antagonists (spironolactone)
88
Pituitary adenoma pathophysiology
- tumour with good margins
| - secretory can cause hyperpituitarism
89
Pituitary adenoma signs and symptoms
- hyperpituitarism if microcytic
- hypopituitarism if macrocytic non secretory
- headache
- bitemporal hemianopia
- diplopia
90
Pituitary adenoma diagnosis
- cranial contrast MRI
- CT scan
- hormone assays
91
Pituitary adenoma treatment
- non secretory/asymptomatic = monitor
- 1st line = transsphenoidal hyposectomy
- 2nd line = pituitary irradiation
92
Addison's pathophysiology
- usually damage to the adrenal cortex or metabolic failure in hormone production
93
Addison's signs and symptoms
- hyperpigmentation
- postural hypertension
- hypoglycaemia
- fatigue
- weight loss
- weakness
94
Addison's diagnosis
- low serum calcium
- high serum potassium
- low serum glucose
- anaemia
- adrenal CT or MRI
- morning serum cortisol is reduced
95
Addison's treatment
- if hypoadrenalism suspected = 100mg of hydrocortisone and saline immediately!
- glucocorticoids and mineralocorticoids
- treat underlying cause
96
Addisonian crisis
- severe hypotension and dehydration often after illness or trauma
- high dose hydrocortisone given
97
Secondary adrenal insufficiency pathophysiology
- hypothalamic pituitary disease leading to decreased ACTH production
- long term steroid therapy leading to hypothalamic pituitary suppression
98
2nd adrenal insufficiency signs and symptoms
- same as addison's apart from no hyperpigmentation
- fatigue
- weight loss
- N&V
- weakness
99
2nd adrenal insufficiency diagnosis
- same as Addison's but more focused on ACTH level
- ACTH stimulation test - not a large enough rise in cortisol
- ACTH level = very low (Addison's will be high)
100
2nd adrenal insufficiency treatment
- steroid therapies
- replacement glucocorticoids and mineralocorticoids
- education on long term steroid use
101
SIADH pathophysiology
- increased ADH secretion leads to receptor-mediated signalling cascade in distal convoluted tubules and collecting duct
- build up of additional aquaporin 2 in luminal cell membrane
- water drawn out of urine into tissues
- release of ADH no longer inhibited by fall in plasma osmolality
102
SIADH signs
- raised JVP
- oedema
- ascites
- cheyne-stokes respiration
- mild hyponatraemia
- fits/coma if severe
103
SIADH symptoms
- N&V
- headache
- lethargy
- cramps
- weakness
- confusion
104
SIADH diagnosis
- ADH levels elevated
- U&E's show low sodium, high or normal potassium
- decreased serum osmolality
105
SIADH treatment
- fluid restriction
- increased salt intake
- increased osmolality
- treat underlying cause
