Thyroid and other endocrine DO Flashcards
The clinical diagnosis of ______disease
is usually obvious with the features of exophthalmos,
hyperkinesis and a large goitre but if the eye and
neck signs are absent it can be misdiagnosed as an
anxiety state
classical Graves
_______ often
has a gradual onset with general symptoms such as
constipation and lethargy.
Hypothyroidism
If with suspected thyroid problems, serum ____ and ______should be requested
thyroid stimulating hormone
(TSH) or thyrotropin
The \_\_\_\_\_level is the most sensitive index of thyroid function and is the preferred test for suspected thyroid dysfunction.
serum TSH
How often to repeat TSH
If necessary repeat TSH in 3–6 months
Serum tri-iodothyronine (T 3 ) measurement and
serum free thyroxine (T 4 ) can be useful in suspected
T 3 toxicosis where ______ level may be normal,
and for monitoring patients with treated thyroid
dysfunction
serum T 4
Raised autoantibodies (antimicrosomal or antithyroid peroxidase) are suggestive of \_\_\_\_\_\_
Hashimoto thyroiditis (autoimmune thyroiditis
_____, _______, _______ are
elevated in Graves disease, the TSH receptor antibody
being very specific for Graves disease
Antithyroglobulin, antithyroid
peroxidase and TSH receptor antibodies
This is the single most cost-effective investigation in the
diagnosis of thyroid nodules. It is the best way to assess
a nodule for malignancy
FNAB
The scan may help in the differential diagnosis of
thyroid nodules and in hyperthyroidism
Thyroid isotope scan
A functioning nodule is said to be less likely to be _______ than a non-functioning nodule
malignant
A _______is usually more sensitive in the
detection of thyroid nodules
thyroid ultrasound
T or F
A multinodular goitre is said to be less likely to be malignant than
a solitary thyroid nodule.
T
_____ of the thyroid may be used particularly to
determine if there is significant compression in the
neck from a large multinodular goitre with retrosternal
extension
CT scan
________ which is relatively common, is
more prevalent in elderly women (up to 5%).
Hypothyroidism,
The
term _____ refers to the accumulation of
mucopolysaccharide in subcutaneous tissues
myxoedema
Dx?
tiredness + husky voice + cold
intolerance
myxoedema
Pts at risk for hypothyroidism
1
2
3
4
• previous Graves disease • autoimmune disorders (e.g. rheumatoid arthritis, type 1 diabetes) • Down syndrome • Turner syndrome
Drugs that may cause hypothyroidism
lithium, amiodarone, interferon
Other conditions that may cause hypothyroidism
• previous thyroid or neck surgery
• previous radioactive iodine treatment of the
thyroid
_______, which is an autoimmune
thyroiditis, is the commonest cause of bilateral nonthyrotoxic
goitre in Australia
Hashimoto thyroiditis
Clinical features of Hashimoto:
- bilateral _____
- classically described as____ and ____
goitre
firm and rubbery
T or F
In patients with Hashimoto:
patients may be hypothyroid or euthyroid with a
possible early period of thyrotoxicosis
T
Hashimoto:
Diagnosis is confirmed by a strongly positive
_______ titre and/or fine
needle aspiration cytology.
antithyroid microsomal antibody
Hashimoto thyroiditis may present as _______
The hypothyroidism may resolve in
____ months or may be permanent.
postpartum hypothyroidism.
6–12
Laboratory diagnosis of hypothyroidism
- T 4 —______
- TSH—______
subnormal
elevated (>10 is clear gland failure)
If T 4 is low and TSH is low or normal, consider
____ and _____
pituitary dysfunction (secondary hypothyroidism) or sick euthyroid syndrome.
A raised TSH
and T 4 in normal range denotes______ and treatment is appropriate albeit
controversial.
‘subclinical’
hypothyroidism
Other diagnostics for Hashimoto:
- Serum cholesterol level elevated
- Anaemia: usually _____
- ECG: _____
normocytic; may be macrocytic
sinus bradycardia, low voltage, flat T waves
Tx of Hashimoto:
Exclude coexisting _____ and _____before T 4 replacement.
hypoadrenalism and ischaemic
heart disease
Tx of Hashimoto:
Treatment as primary hypothyroidism when
hypopituitarism is the cause may precipitate ____
adrenal
crisis
How to give Thyroxine
Thyroxine 100–150 mcg daily (once daily)
Thyroxine:
Start with low doses (25–50 mcg daily) in
____ and ________and
50–100 mcg in others
elderly and those with ischaemic heart disease
TSH level in Hashimoto to say its treated:
Aim to achieve TSH levels of 0.5–2 mU/L.
How long is the tx for Hashimoto
When stable on
optimum dose of T 4 , monitor every 2–3 years.
Treatment is usually lifelong.
Hashimoto Tx:
Ischaemic heart disease. Rapid thyroxine
replacement can precipitate _______ especially in the elderly
myocardial infarction,
Hashimoto Tx:
Pregnancy and postpartum. Continue thyroxine
during pregnancy; watch for ______ (an
increased dose of T 4 is often required).
hypothyroidism
Elective surgery. If euthyroid, can stop thyroxine
for ______ If subthyroid, defer surgery until
euthyroid
one week.
____. Urgent hospitalisation under
specialist care is required. Intensive treatment
is required, which may involve parenteral T 4
or T 3 .
Myxoedema coma
Misdiagnosing this serious condition leads to failure to
thrive, retarded growth and poor school performance.
Neonatal hypothyroidism
If neonatal hypothy (NH) is not treated, what is the cx?
If untreated it leads to permanent intellectual damage
(cretinism
Dx of NH
It is detected by routine neonatal heel prick blood
testing.
Clinical features of NH
The clinical features of the newborn
include coarse features, dry skin, supra-orbital oedema,
jaundice, harsh cry, slow feeding and umbilical hernia
In NH, Thyroxine replacement should be started as
soon as possible, at least before _____weeks of age to avert
intellectual retardation.
2
_____ is also relatively common and may
affect up to 2% of women, who are affected four to
five times more often than men
Hyperthyroidism
_____ is the most common cause Hyperthyroidism followed closely by
_____
Graves disease
nodular thyroid disease
Other causes of hyperthyroidism
- Autonomous functioning nodules
- Subacute thyroiditis or ________—
viral origin
3.Excessive intake of thyroid hormones—
_______ - Iodine excess
- ______(beware of this drug)
(de Quervain thyroiditis)
thyrotoxicosis factitia
Amiodarone
T or F, in patients with hyperthyroidism:
The classic symptoms may be lacking in elderly
patients who may have only cardiovascular
manifestations (e.g. unexplained heart failure or
cardiac arrhythmias).
T
Care has to be taken not to dismiss hyperthyroidism
as severe _____
anxiety.
anxiety + weight loss + weakness
thyrotoxicosis
4 eye signs of hyperthyroidism
• Lid retraction (small area of sclera seen above iris) • Lid lag • Exophthalmos • Ophthalmoplegia in severe cases
Investigation for thyrotoxicosis
- T 4 (and T 3 ) _____
- TSH level ____
- Radioisotope scan
- Antithyroid peroxidase
elevated
suppressed
The isotope scan enables a diagnosis of Graves
disease to be made when the scan shows ___
uniform increased uptake
Isotope scan:
Increased irregular uptake would
suggest a ______, while there is
poor or no uptake with _____ and ______
toxic multinodular goitre
Quervain thyroiditis and
thyrotoxicosis factitia.
Management of thyrotoxicosis
• Establish the precise cause before initiating
treatment.
• Educate patients and emphasise the possibility
of development of _____ and _____ and the need for lifelong
monitoring.
• Monitor for _____ and _____
recurrent hyperthyroidism
or hypothyroidism
cardiovascular complications and
osteoporosis
Therapy of thyrotoxicosis
- _____
- Thionamide antithyroid drugs
RAI
Initial doses of antithyroid drugs
— \_\_\_\_\_\_ 10–45 mg (o) daily in divided doses or —\_\_\_\_\_\_ 200–600 mg (o) daily in divided doses
carbimazole
propylthiouracil
Adjunctive drugs for thyrotoxicosis
— beta blockers (for symptoms in acute florid phase, e.g. propranolol 10–40 mg, 6 to 8 hourly); \_\_\_\_\_ and \_\_\_\_\_\_are alternatives — \_\_\_\_\_\_(rarely used when there is intolerance to thionamides) — \_\_\_\_\_\_\_ mainly used prior to surgery
diltiazem or atenolol
lithium carbonate
Lugol’s iodine:
Type of surgery for thyrotoxicosis
• Surgery
— subtotal thyroidectomy
or
— total thyroidectomy
Guidelines for Mx of Graves
Younger patients with small goitres and mild
case—_______
Older patients with small goitres—as above or
_____ (preferably when euthyroid)
18-month course antithyroid drugs
radioiodine
Large goitres or moderate-to-severe cases—
antithyroid drugs until euthyroid, then ____ or _____
surgery
or 131 I
Hyperthyroidism is usually transient and follows
a surge of thyroxine after a viral-type illness.
Symptoms include pain and/or tenderness over the
goitre (especially on swallowing) and fever
subacute thyroiditis
Tx of acute phase of subacute thyroiditis
In the
acute phase treatment is based on rest, analgesics (aspirin 600 mg (o) 4–6 hourly) and soft foods.
What to give if with severe pain in subacute thyroiditis
Rarely, when pain is severe, corticosteroids may be
used.
Clinical features are marked anxiety, weight
loss, weakness, proximal muscle weakness,
hyperpyrexia, tachycardia (>150 per minute),
heart failure and arrhythmias. It is usually
precipitated by surgery or an infection in an
undiagnosed patient
Thyroid crisis (thyroid storm
A _______ is defined as a discrete lesion on
palpation and/or ultrasonography that is distinct
from the rest of the thyroid gland.
thyroid nodule
Etiology of thyroid nodules
• Dominant nodule in a multinodular goitre (most
likely)
• Colloid cyst
• True solitary nodule: adenoma, carcinoma
(papillary or follicular
Dxtics for thyroid nodule
1
2
3
- Ultrasound imaging
- Fine-needle aspiration cytology
- Thyroid function tests
________ is the most common malignancy.
Although rare compared with non-malignant lesions
(such as colloid nodules, cysts, haemorrhage and
benign adenomas), it is important not to miss
carcinoma because of the very high cure rate with
treatment.
Papillary carcinoma
Dx of thyroid CA
Fineneedle
aspiration is the investigation of choice.
Pituitary tumors:
These are invariably benign _____ They can
present with hormone deficiencies, features of
_______ syndromes (e.g. prolactin, GH, ACTH)
or by local tumour mass symptoms (e.g. headache,
visual field loss
adenomas.
hypersecretory
The main causes (of many) are a pituitary adenoma
(micro- or macro), pituitary stalk damage, drugs—
such as antipsychotics, various antidepressants,
metoclopramide, cimetidine, oestrogens, opiates,
marijuana—and physiological causes such as
pregnancy and breastfeeding
Hyperprolactinaemia
SSx of hyperprolactinemia
• Symptoms common to males and females:
reduced libido, subfertility, ______ (mainly
females)
• Females: ______
• Males: erectile dysfunction, reduced facial hair
galactorrhoea
Amenorrhoea/oligomenorrhoea
hyperprolactinemia
- Serum ____ and _____ assays
- MRI: consider if headache, etc
prolactin and macroprolactin
Hyperprolactinemia
Refer for management, which may include
a dopamine agonist such as _____ and _____
cabergoline or
bromocriptine
Dx
nasal problems + fitting problems ( e. g.
rings, shoes ) + sweating
acromegaly
Dx of acromegaly
- Plasma ____ excess
- Elevated ____—the key test
- X-ray skull and hands
- MRI scanning pituitary
- Consider associated __________
growth hormone
insulin-like growth factor 1 (IGF-1)
(somatomedin)
impaired glucose tolerance/
diabetes
Impaired secretion of vasopressin (antidiuretic
hormone) from the posterior pituitary leads to
polyuria, nocturia and compensatory polydipsia
resulting in the passage of 3–20 L of dilute urine per
day
DI
In ______the kidney
tubules are insensitive to vasopressin
nephrogenic DI
DDx for nephrogenic DI
compulsive (psychogenic) water
drinking
The______ is caused by cancer
(e.g. lung, lymphomas, kidney, pancreas), pulmonary
disorders, various intracranial lesions and drugs such
as carbamazepine and many antipsychotic agents
syndrome of secretion of inappropriate antidiuretic hormone (SIADH)
Tx of SIADH
Management of SIADH is essentially fluid restriction
weakness + polyuria + polydipsia
diabetes insipidus
What is the dx?
- a history of postpartum haemorrhage
- symptoms of hypothyroidism
- symptoms of adrenal insufficiency
- symptoms suggestive of a pituitary tumour
- thin, wrinkled skin: ‘monkey face’
- pale ‘alabaster’ skin/hairlessness
Hypopituitarism 7
( female ): amenorrhoea + loss of
axillary and pubic hair + breast atrophy
Hypopituitarism
( male ): ↓ libido + impotence + loss of
body hair
Hypopituitarism
Hypopituitarism:
Investigate with serum pituitary hormones,
imaging and ____
triple stimulation test
Uncommon disorders of the adrenal cortex
_______ deficiency of cortisol and aldosterone
________—cortisol excess
• primary hyperaldosteronism
chronic adrenal insufficiency (Addison disease)
• Cushing syndrome
Autoimmune destruction of the adrenals is the most
common cause.
Addison disease
What is the dx?
Clinical features
• Lethargy/excessive fatigue/weakness • Anorexia and nausea • Diarrhoea/abdominal pain • Weight loss • Dizziness/funny turns, syncope: hypoglycaemia (rare); postural hypotension (common) • Hyperpigmentation, especially mucous membranes of mouth and hard palate, skin creases of hands
Addison Disease
If Addison disease remains undiagnosed, wasting
leading to death may occur. _________can
be a feature
Severe dehydration
fatigue + a / n / v + abdominal pain
± skin discolouration
Addison disease
Dx of Addison
Elevated serum ____, low serum____
• Low plasma ______level (fails to respond to
synthetic adrenocorticotropic hormone [ACTH])
potassium, sodium
cortisol
Dx of Addison
• The short_______test is the
definitive test
• Consider adrenal autoantibodies and imaging
calcification of adrenals
synacthen stimulation
Tx of Addison
corticosteroid replacement—
hydrocortisone/fludrocortisone acetate
An______ develops because of an inability
to increase cortisol in response to stress, which may
include intercurrent infection, surgery or trauma.
Addisonian crisis
SSx of Addisonian crisis
- Nausea and vomiting
- Acute abdominal pain
- Severe hypotension progressing to shock
- Weakness, drowsiness progressing to coma
The five main causes of Cushings are: \_\_\_\_\_\_—chronic corticosteroid administration \_\_\_\_\_\_ excess (Cushing disease) • bilateral adrenal hyperplasia • adrenal tumour (adenoma, adenocarcinoma) \_\_\_\_\_\_\_ or (rarely) corticotrophin-releasing hormone (CRH) from nonendocrine tumours (e.g. oat cell carcinoma of lung)
- iatrogenic
- pituitary ACTH
- ectopic ACTH
plethoric moon face + thin extremities +
muscle weakness
Cushing syndrome
Diagnosis (apart from iatrogenic cause) of Cushing
• Cortisol excess (plasma or 24-hour urinary cortisol) • \_\_\_\_\_\_\_test • \_\_\_\_\_\_\_ sampling • Serum ACTH • Radiological localisation: MRI for ACTHproducing pituitary tumours; CT scanning for adrenal tumours
Dexamethasone suppression
Inferior petrosal sinus
Primary hyperaldosteronism is usually from?
Most commonly due to an adrenal adenoma
Usually asymptomatic but any symptoms are features
of hypokalaemia
- weakness
- cramps
- paraesthesia
- polyuria and polydipsia
Conn syndrome
A dangerous tumour of the adrenal medulla
Phaeochromocytoma
Ssx of Phaeochromocytoma
• hypertension • headache (throbbing) • sweating • palpitations • pallor/skin blanching • rising sensation of tightness in upper chest and throat (angina can occur
Phaeochromocytoma
• Series of three 24-hour ___ and inc in ______
• Abdominal CT or MRI scan
free catecholamines
↑ VMA
Tx of Phaeochromocytoma
Excise tumour, cover with ___ and ____
alpha and beta
blockers
An AR condition with 21-hydroxylase deficiency
being the most common of several forms. There is
inadequate synthesis of cortisol and aldosterone with
increased androgenisation
Congenital adrenal hyperplasia
adrenogenital syndrome
In CAH,
Major problem is adrenal
failure ± _____
salt-losing state (SLS).
CAH in females:
In females, ____ and ______ before puberty
usually occurs.
ambiguity
of external genitalia and hirsutism
CAH in males
Males may have normal urogenital development but ______ is a concern
SLS
CAH in infants
Infants of either
sex may present with_____ and _____ and
dehydration (SLS).
failure to thrive or vomiting
Tx of CAH
Lifelong glucocorticoid treatment
is required.
Other term for adrenal tumors
‘incidentalomas’
example of adrenal tumors
adrenal carcinoma,
phaeochromocytoma, neuroblastoma, glucocorticoid
or a mineral corticoid secreting tumour
Suspect___________if there is weakness, tiredness,
malaise, anorexia, nausea or vomiting, abdominal
pain, constipation, thirst, polyuria, drowsiness,
dizziness, personality changes, muscle aches and
pains, visual disturbances
hypercalcaemia
MC causes of primary hyperparathyroidism
familial hypercalciuric hypercalcaemia and neoplasia,
Other causes of primary hyperparathyroidism
include Paget disease,
sarcoidosis and milk-alkali syndrome
Investigations for primary hyperparathyroidism
ESR, serum parathyroid hormone (N: 1.0–7 pmol/L), serum ACE levels, serum alkaline phosphatase, chest X-ray,
What scans are used in primary hyperparathyroidism
Sestamibi scan and bone scan
weakness + constipation + polyuria
hypercalcaemia
cramps + confusion + tetany
hypocalcaemia
Hyperparathyroidism is caused by an excessive
secretion of parathyroid hormone and is usually due
to a _____
parathyroid adenoma.
The classic clinical features
of hyperparathyroidism are due to the effects of
_______
hypercalcaemia.
Rarely, a_________ in a
misdiagnosed patient may result in death from severe
hypercalcaemia.
parathyroid crisis
Dx of Primary hyperparathyroidism
1
2
- Serum parathyroid hormone (elevated)
* TC-99m Sestamibi scan to detect tumour
This usually presents with tetany or more
generalised neuromuscular hyperexcitability and
neuropsychiatric manifestations
Hypocalcaemia
The sensory
equivalents are paraesthesia in the hands, feet and
around the mouth (distinguish from tetany seen in
the_________).
respiratory alkalosis of hyperventilation
Hypocalcemia
The diagnosis is by
measurement of serum total calcium concentration in
relation to serum ____
albumin
Two important signs of hypocalcemia are:
• ______ occlusion of the brachial artery
with BP cuff precipitates carpopedal spasm (wrist
flexion and fingers drawn together)
• ________ tapping over parotid (facial nerve)
causes twitching in facial muscles
Trousseau sign:
Chvostek sign:
Tx of Hypocalcemia
Treatment involves careful adjustments in dosage
of calcitriol and calcium to correct hypocalcaemia and
avoid hypercalcaemia and hypercalciuria
Hypoparathyroidism is the most common cause
of ______
hypocalcaemia
Causes of Hypoparathyroidism
- postoperative thyroidectomy and parathyroidectomy,
- congenital deficiency (DiGeorge syndrome) and
- idiopathic (autoimmune) hypoparathyroidism
Main ssx of Hypoparathyroidism
1
2
3
neuromuscular hyperexcitability, tetany
and neuropsychiatric manifestations
