Endocrine Flashcards
1
Q
What is the clinical chemistry and PTH levels in hypoparathyroidism?
A
Low PTH
Low Calcium
High/Normal PO3
Inappropriate response
2
Q
List the primary and secondary causes of hypoparathyroidism?
A
Primary- Gland failure
* Autoimmune
* DiGeorge syndrome
Secondary- Gland removal
* Low Magnesium
3
Q
List the sx of hypocalcaemia?
A
Convulsions
Arrhythmias
Tetany
Spasms
Numbness
4
Q
List the signs of hypocalcaemia?
A
Chvosteks sign- tapping over parotid causes facial muscles to twitch
Trousseaus sign- ‘Italian hand’
ECG- QT prolongation
5
Q
What is the clinical chemistry and PTH levels in pseudohypoparathyroidism?
A
High PTH
Low calcium
Appropriate response
6
Q
What is pseudohypoparathyroidism?
A
Genetic disorder in which the body is resistant to PTH because of mutations
7
Q
List the features of pseudohypoparathyroidism?
A
Short 4th and 5th metacarpals
Low IQ
Short
Round obesity
8
Q
What is the clinical chemistry and PTH levels in primary hyperparathyroidism?
A
High PTH
High Calcium
Low PO3
Inappropriate response
9
Q
List the most common cause of primary hyperparathyroidism?
A
Solitary adenoma (80%)
10
Q
List the causes of primary hyperparathyroidism?
A
Solitary adenoma
Hyperplasia (15%)
Multiple adenoma/carcinoma
11
Q
List the sx of hypercalcaemia?
A
BONES, STONES, MOANS, THRONES, GROANS
Bone pain/fractures
Renal stones
depression
polydipsia/polyuria
Abdo pain/constipation/N+V, Pancreatitis, peptic ulceration etc
12
Q
What is the Gs tx of primary hyperparathyroidism?
A
Parathyroidectomy
13
Q
What is secondary hyperparathyroidism?
A
Parathyroid hyperplasia due to vit d deficiency or CKD
14
Q
What is the clinical chemistry and PTH levels in secondary hyperparathyroidism?
A
High PTH
Low Calcium
High/N PO3
Low Vit D
Appropriate response
15
Q
What is tertiary hyperparathyroidism?
A
Prolonged secondary hyperparathyroidism causes gland to autonomously undergo hyperplasia
16
Q
What is the clinical chemistry and PTH levels in tertiary hyperparathyroidism?
A
Very High PTH
High calcium
17
Q
List 5 causes of hypercalcaemia?
A
90% = malignancy + primary hyperparathyroidism
Sarcoidosis
Multiple myeloma
Acromegaly
Thiazides
Thyrotoxicosis
18
Q
What is the mx of hypercalcaemia?
A
IV fluids (0.9 NaCl) w/ crystalloid
1st line- Bisphosphonates for a week
2nd- calcitonin
19
Q
What is mx for mild and severe hypocalcaemia?
A
Mild
* Oral supplements
severe
* IV calcium gluconate (10ml of 10% solution over 10 mins) in 100mls sodium chloride 0.9% or glucose 5%
* + ECG monitoring
20
Q
List 3 causes of pituitary adenomas?
A
Prolactinoma
Acromegaly
Cushing’s syndrome
21
Q
What is a prolactinoma?
A
A benign adenoma secreting prolactin
22
Q
What substance inhibits prolactin secretion?
A
Dopamine
23
Q
List 2 functions of prolactin?
A
Stimulates breast development in puberty
Stimulates milk production
24
Q
What substances are inhibited by the secretion of prolactin?
A
Sex hormones (oestrogen and testosterone)
25
List 5 sx of a prolactinoma?
Galactorrohoea
Amenorrhoea/Oligo menorrhoea
ED/Loss of libido/Infertility
Bitemporal hemianopia/Headaches
26
What is the 1st line and Gs Ix in prolactinoma?
1st line- serum prolactin
Gs- MRI/CT pituitary
27
What is the 1st line and Gs mx of prolactinoma?
1st line- Cabergoline- Dopamine agonist
Gs- Transphenoidal surgery
28
What is the difference between acromegaly and gigantism?
Gigantism- excess GH in children (before the fusion of growth plates)
Acromegaly- excess GH in adults
29
List 5sx of acromegaly?
* Frontal bossing
* Large tongue/nose/jaw/hands/feet
* Skin tags
* OSA
* Headaches/Bitemporal hemianopia
30
What substance inhibits the release of GH?
Somatostatin
31
What is the 1st line Ix of acromegaly?
Serum IGF-1 levels (elevated)
32
What is the Gs Ix for acromegaly?
OGTT- High levels of Glucose should suppress GH
33
What is the mx of acromegaly (1st - 4th line)
1st line- TSS
2nd line- Somatostatin analogue e.g. octreotide
3rd- GH receptor antagonist e.g. pigvisomant
4th line- Dopamine agonist e.g. bromocriptine/cabergoline
34
What is Cushing's syndrome?
Excess glucocorticoids resulting in distinguished clinical signs and sx
35
What is Cushing's disease?
Glucocorticoid excess caused by ACTH pituitary tumour
36
List the causes of Cushing's?
ACTH dependent-Pituitary tumours and Ectopic ACTH tumour
ACTH independent-Adrenal adenoma/carcinoma, exogenous steroids
37
List 5 sx or signs of Cushing's?
Moon face
obesity
Purple striae
Buffalo hump
Acne
Hirsutism
Mood changes
Irregular menses/ED
WG
High BG/HTN
38
What is the Ix for Cushing's?
39
What are the sick day rules regarding patients taking steroids?
Patients on long term steroids should have double the dose during intercurrent illness
40
What drugs can cause gynaecomastia?
Spironolactone
Digoxin
Oestrogen
Anabolic steroids
Finasteride
GnRH analogues- gosrelin
41
What is subclinical hyperthyroidism, and what conditions is it associated with?
Normal T4/T3
Low TSH (<0.1mu/L)
Associated with AFib and Osteoporosis
42
What is cranial diabetes insipidus?
Decrease secretion of ADH from pituitary gland
43
What is nephrogenic diabetes insipidus?
Insensitivity to ADH
44
Where is ADH produced?
Supra-optic nucleus in the hypothalamus
45
Where is ADH released from?
Posterior pituitary
46
How does ADH respond to dehydration/thirst?
High ECF osmolality detected by hypothalamus > release of ADH from post. pit > renal water retention >decrease in ECF osmolality
47
What is the 1st line and gold standard Ix in diabetes insipidus?
1st line-Water deprivation test (confirms the presence of DI)
GS- Desmopressin stimulation test (differentiates between NDI and CDI)
48
What results in the water deprivation test would be indicative of DI?
Urine osmolality- Low
Serum Osmolality- High
49
What would the results of the desmopressin simulation test be in those with CDI and in NDI?
CDI-
serum osmolality- low
Urine osmolality- high
NDI
serum osmolality- high
Urine osmolality- low
50
List the signs of graves disease?
Thyroid acropachy (digital clubbing, soft tissue swelling of the hands and feet, and periosteal new bone formation)
Exophthalmos
Pretibial myxoedema
Smooth enlarged non tender goitre
50
List 5 causes of hyperthyroidism?
Toxic multinodular goitre
Iodine excess
Drugs- Amiodarone, Lithium
Gestational
Toxic adenoma
Graves
51
What is the mx of hyperthyroidism?
Carbimazole or Propythiouracil
Thyroidectomy
52
What is the Ix for Graves disease?
TSH/T4 levels (Low TSH, High T4)
Anti TSH antibodies
53
List the 4 stages in De-quervains thyroiditis?
1- hyperthyroidism (painful goitre and high ESR)
2- Euthyroid
3- Hypothyroidism
4- Normalcy
54
What is the Ix that is used to diagnose De-Quervains/subacute thyroiditis?
Thyroid Scintigraphy- globally reduced uptake of I2-131
55
What is the most common type of thyroid cancer?
Papillary (70%)
56
List 5 sx and signs of hypothyroidism?
Cold intolerance
Constipation
Lethargy
Menorrhagia
Dry/coarse hair
Loss of lateral 1/3 eyebrow
Carpal tunnel syndrome
Dry skin
WG
57
What is the mx of hypothyroidism?
Levothyroxine
58
What Ix relevant to Hashimoto's?
Anti TPO
TSH/T4 (High TSH, low t4)
59
What is SIADH?
Syndrome where too much ADH is released
60
List 5 causes of SIADH?
Malignancy (ectopic/pituitary)
Neurological (stroke/SAH/meningitis)
Infections
Post-operative
Drugs
61
What drugs can cause SIADH?
CARDISH
Chemotherapy
Antidepressants
Recreational
Diuretics
Inhibitors (SSRIs, ACEIs)
Sulfonyureas
Hormones (Desmopressin)
62
What is the triad of features that is present in SIADH?
Hyponatraemia
High urine Na+
Euvolaemia
63
What ix are conducted to make a diagnosis of SIADH?
SIADH is a diagnosis of exclusion.
Addison's disease must be excluded via short synACTHen test
Urine osmolality-high
Serum Osmolality-low
64
List the sx of SIADH?
* Absence of hypo/hypervolaemia
* Nausea and Vomiting
* Headaches
* Fatigue
* Muscle cramps and aches
65
What is Addison's disease?
Autoimmune destruction of adrenal glands thus decrease secretion of cortisol and aldosterone
66
What is the most common cause of Addison's in the world?
TB
67
What is the most common cause of Addison's in the UK/Developed world?
Autoimmune
68
List the layers of the adrenal glands and what hormones are subsequently released?
Medulla - Adrenaline and noradrenaline
Cortex:
1. Zona Glomerulosa- Mineralocorticoids (Aldosterone)
2. Zona Fasiculata- Glucocorticoids (Cortisol)
3. Zona Reticularis- Sex hormones (DHEA)
69
List the sx of Addison's disease?
Tanned
Lean
Palmar hyperpigmentation
WL
Hypotension
N+V
70
What is the Ix's for Addison's disease?
Short Synacthen Test-
give synthetic ACTH, in healthy pts cortisol should be produced (x2 of baseline), however in Addison's since the glands are damaged no/little cortisol is produced.
Electrolytes- Hyponatraemia, Hyperkalaemia, Hypoglycaemia
High renin, High ACTH, Low cortisol, Low aldosterone
71
What is the mx of Addison's disease?
Lifelong Fludrocotisone and Hydrocortisone
72
What are signs of Addison's crisis?
Hypotension
Altered consciousness
Hyponatraemia, Hyperkalaemia
73
What is the mx of Addison's crisis?
IV hydrocortisone
IV fluids resus
Correct hypoglycaemia
74
What is Conn's syndrome?
Primary hyperaldosteronism
75
List the 2 most common causes of Conn's syndrome?
Adrenal adenoma
Bilateral adrenal hyperplasia (*)
76
What is the job of aldosterone?
1. Acts on distal tubule which increases Na+ reabsorption
2. Acts on distal tubule which increases K+ secretion
77
What are the sx of Conn's syndrome?
HTN**
Lethargy
mood disturbances
Nocturia
Polyuria
Metabolic alkalosis
78
What is the first line Ix of Conn's syndrome?
Aldosterone:Renin ratio
Primary-High Aldosterone to Renin ratio
Secondary-Low aldosterone to renin ratio
79
What is the mx for Conn's Syndrome?
Adrenal adenoma- Surgery
BL adrenal hyperplasia- Spironolactone (aldosterone antagonist)
80
What is secondary adrenal insufficiency?
Affects pituitary therefore low ACTH production thus less cortisol but normal aldosterone and renin
81
What Ix and results would indicate secondary adrenal insufficiency?
Short synacthen test- Give synthetic ACTH and cortisol would increase
Low cortisol, Low ACTH, Normal renin and Normal Aldosterone
82
What is carcinoid syndrome?
The release of serotonin into systemic circulation from a carcinoid tumour
83
Where do carcinoid tumours commonly arise from?
1. GI tract
2. Lungs
3. Liver
4. Ovaries
5. Thymus
84
What is the most common GI site for carcinoid tumours?
Appendix
85
What is the most common site for carcinoid mets?
Liver
86
List sx and signs of carcinoid syndrome?
Flushing
Diarrhoea
Bronchospasm- Wheezing
Pulmonary stenosis
Abdo pain
Pellagra (Niacin/B3 deficiency)
87
What is the triad of sx in pellagra?
Diarrhoea
Dementia
Dermatitis
88
What is the first line Ix of Carcinoid syndrome?
1st- High urinary 5-hydroxyindoloacetic acid
89
What is the GS ix for Carcinoid syndrome?
Chromogranin A and Octreoscan
90
What is the mx of carcinoid syndrome?
Somatostatin analogue- Octreotide
Surgery
91
What amino acid is converted into serotonin?
Tryptophan
92
What is a carcinoid crisis?
When a tumour outgrows its blood supply. It is a life-threatening crisis which causes Vasodilation, Hypotension, Tachycardia, Bronchoconstriction and hyperglycaemia
93
94
What is serotonin syndrome?
Excess synaptic serotonin in CNS that clinically manifests as a triad of sx (Neuromuscular excitation, Autonomic effects and altered mental status)
94
What is phaechromocytoma?
A tumour arising from catecholamine producing chromaffin cells of adrenal glands (Adrenaline and Noradrenaline)
94
List the sx of phaechromocytoma?
5Ps
Perspiration
Palpitations
Pallor
High BP
Pain (headache)
95
What is the 1st line and other important Ix for phaechromocytoma?
1st line- 24 hour collection of catecholamines- High
Other- CT/MRI abdo
96
What is the mx of phaechromocytoma?
Alpha and Beta Blockers
GS- Surgery
97
What is the primary anion in the ECF
Cl-
98
What is the primary cation in ECF?
Na+
99
What is the primary cation in ICF?
K+
100
What is T1DM?
Autoimmune destruction of beta cells of the pancreas resulting in absolute deficiency of insulin, thus increasing glucose levels.
101
Where is glucagon released from and what does it do?
Glucagon released from alpha cells (Turns Glycogen into Glucose)
102
Where is insulin released from and what does it do?
Beta cells (Glucose to glycogen)
103
What are the Ix necessary to diagnose T1DM?
Fasting glucose >7.0mmol/L
Random glucose >11.1mmol/L
HbA1c >48mmol/L
104
What is the Tx for T1DM?
Insulin and Education
105
What are the complications of T1DM?
Lipodystrophy, Hypoglycaemia, WG, micro/macro vascular complications, DKA
106
How does insulin work?
Insulin activates insulin-receptors on the membranes of insulin-responsive tissues (e.g. peripheral muscle and adipose tissue), stimulating the migration of glucose transporters to the cell membrane to facilitate uptake of circulating glucose into these tissues.
In the absence of insulin (as in T1DM), glucose cannot be taken up by insulin-responsive tissues, causing hyperglycaemia.
107
list the micro and macrovascular complications of diabetes?
Micro- nephropathy, retinopathy and neuropathy
Macro- Cardiovascular, cerebrovascualr, aor peripheral vascualr disease
108
List the sx of T1DM?
Polydipsia
Polyuria
Nocturia
WL
Fatigue
Blurred vision
109
What is DKA?
Complication of T1DM
110
What is the pathophysiology of DKA?
DKA is caused by uncontrolled lipolysis, which results in an excess of free fatty acids that are ultimately converted to ketone bodies
111
List the clinical features of DKA?
Abdominal pain
Polyuria, polydipsia, dehydration
Kussmaul respiration (deep hyperventilation)
pear drop smelling breath
112
What is the diagnostic criteria for DKA?
Random glucose >11mmol/L
pH <7.3
Bicarbonate <15mmol/L
Ketone >3mmol/l or ++ urinary ketones
113
What is the mx of DKA?
1. Fluid replacement- Isotonic saline
2. Insulin infusion (start on 0.1unit/kg/hour)
- Once blood glucose is < 14 mmol/l an infusion of 10% dextrose should be started at 125 mls/hr in addition to the 0.9% sodium chloride regime
3. Correction of electrolyte disturbances
4. Long acting insulin should be continued, short-acting insulin should be stopped
114
What is T2DM?
A polygenic disorder in which there is progressive relative insulin deficiency and cells become insulin resistance
115
List the RF for T2DM diabetes?
Obesity, Male, South Asians, Lack of exercise, FHx
116
What is pre-diabetes?
HbA1c level of 42-47 mmol/mol
117
What are the 2 types of impaired glucose regulation?
Impaired fasting glucose (IFG) - due to hepatic insulin resistance
Impaired glucose tolerance (IGT) - due to muscle insulin resistance
118
What is IFG?
IFG is defined by elevated blood glucose levels after an overnight fast but not high enough to be classified as diabetes.
fasting glucose greater than or equal to 6.1 but less than 7.0 mmol/l implies impaired fasting glucose (IFG)
119
What is IGT?
IGT is characterized by elevated blood glucose levels after consuming a glucose-rich drink (oral glucose tolerance test) but not high enough to be classified as diabetes.
fasting plasma glucose less than 7.0 mmol/l and OGTT 2-hour value greater than or equal to 7.8 mmol/l but less than 11.1 mmol/l
120
What is HHS?
a metabolic emergency of uncontrolled T2DM
121
List the sx of HHS?
Hypovolaemia
Marked hyperglycaemia
Raised serum osmolarity
Fatigue
N+V
Altered level conciousness
Dehydration
Hypotension/Tachy
122
What is the mx of HHS?
Normalise Osmolality
1. Replace fluid and electrolytes (IV 0.9 Saline)
2. Insulin
3. VTE Prophylaxis
123
What are the causes of hyperglycaemia?
Reduced Insulin Secretion
Reduced insulin utilisation
Increase glucose production
Pancreatitis
124
What are the causes of hypoglycaemia?
Diabetes
Non diabetic causes (EXPLAIN)
Exogenous drugs
Pituitary Insufficiency
Liver failure
Addisons
Insulinoma
Non pancreatic neoplasm
125
List the ECG changes seen in Hypokalaemia?
Small/Inverted T waves
Prominent U waves
Long PR interval
Depressed ST segment
126
List the ECG changes seen in Hyperkalaemia?
Tall tented T waves
Small/Absent P waves
Wide QRS complex
Prolonged PR interval
127
What is the mx of hyperkalaemia?
if cardiotoxicity- IV calcium gluconate
if no cardiotoxic and no ECG-Insulin dextrose infusion w/ nebulised salbutamol
128
What’s the 1st line thx for DMT2
Lifestyle modifications
129
What drug class does metformin belong to?
Biguanide
130
What is the MOA of metformin?
Increases insulin sensitivity and decreases hepatic gluconeogenesis
131
What are the side effects of metformin
Lactic acidosis*
| GI upset
132
What is the MOA of sulfonylureas
Stimulate beta pancreatic cells to produce insulin by binding to ATPk channels on beta cells
133
What is the side effects of sulfonylureas
Weight gain
Hypoglycaemia*
Hyponatremia
GI upset
134
What do sulfonylureas drugs end in
Glimepride
| Glicazide
135
What is the MOA of thiazolidinediones
Promote adipogenesis and ffa uptake
136
What are the side effects of thiazolidinediones
Weight gain
| Fluid retention
137
Name a thiazolidinediones drug
Pioglitazone
138
What is the MOA do DPP-4 inhibitors
Increase incretin levels which inhibit glucagon secretion
139
What are the side effects of DPP-4 Inhibitors
Generally well tolerated but increase risk of pancreatitis
140
What to DPP-4 inhibitors drugs name end in
Gliptins
141
What is the MOA of SGLT2- inhibitors
Inhibit reabsorption of glucose in the kidneys
142
What are the side effects of SGLT2-Inhibitors
Weight loss, UTI
143
What do SGLT2-Inhibitors drug name end in
Gliflozins
144
What is the MOA of GLP-1 agonists
Incretin mimetic thus inhibit glucagon secretion (s/c)
145
Side effects of GLP-1 agonists
Weight loss, N+V, Pancreatitis
146
What do glp-1 agonist drugs end in
-tides
147
What test can differentiate between Cushing's and pseudo-cushing's?
Insulin stress test
148
High-dose dexamethasone suppression test shows:
Cortisol- not suppressed
ACTH- suppressed
What is the most likely diagnosis?
Adrenal adenoma
149
High-dose dexamethasone suppression test shows:
Cortisol- suppressed
ACTH- suppressed
What is the most likely diagnosis?
Cushing's Disease- Pituitary adenoma
150
High-dose dexamethasone suppression test shows:
Cortisol- not suppressed
ACTH- not suppressed
What is the most likely diagnosis?
Ectopic ACTH syndrome
151
What is congenital adrenal hyperplasia?
An autosomal recessive disorder that impairs adrenal steroid biosynthesis
152
What is the most common cause of CAH?
21 hydroxylase deficiency
also, 11 beta hydroxylase deficiency, and 17 hydroxylase deficiency
153
List the sx present in CAH?
Ambiguous genitalia
Salt wasting crisis
Precocious puberty
Infertility
Height and growth abnormalities
154
What is the Ix of choice for diagnosing CAH?
ACTH stimulation test
155
What is the thyroid function test results in sick euthyroid syndrome?
Acute illness
Normal TSH
Low T3/T4
156
What is the preferred tx for MODY?
Gliclazide
157
What is kallman's syndrome?
X linked recessive disorder causing delayed puberty secondary to hypogonadotropic hypogonadism
158
List the sx associated with kallmans?
Anosmia
delayed puberty
Low sex hormones
Low FSH, LH
159
What is the HbA1c Target in order to start a second drug in T2DM mx?
>58mmol/L
160
What is the maximum dose of metformin in T2DM?
2g/day
161
What are features associated with MEN type 1?
3Ps
Parathyroid- hyperparathyroidism
Pituitary
Pancreas- insulinoma, gastrinoma. Recurrent peptic ulceration
162
What are the features of MEN type IIa?
Medullary thyroid cancer
2Ps
Parathyroid
Phaechromocytoma
163
What are the features MEN type IIb?
Medullary thyroid cancer
Phaechromocytoma
Marfanoid body habitus, Neuroma
164
What is the MOA of carbimazole?
Inhibits thyroid peroxidase
165
What malignancy is closely linked with acromegaly?
Colorectal cancer
166
In unexplained hypoglycaemia, what further test can you perform to differentiate between exogenous and endogenous insulin?
C-Peptide and Proinsulin
High serum insulin and High C peptide and proinsulin = Endogenous e.g. insulinoma
High serum insulin and low C peptide and proinsulin = Exogenous
167
What is the sick day rules for T1DM?
Continue taking insulin as normal, but check BMs more regularly
168
What are the T1DM blood glucose targets?
5-7mmol/l on waking
4-7mmol/l before meals and other times
169
How does hyperthyroidism and hypothyroidism affect menses?
Hyperthyroidism- Oligo menorrhoea/Amenorrhoea
Hypothyroidism- Menorrhagia
