Week 3 (2) Flashcards
What is the commonest cause of hypo/hyper thyroidism?
Autoimmune thyroid disease
What has low TSH, high T4 and T3?
Hyperthyroidism
What has high TSH, and low T4/T3?
Hypothyroidism
What condition has high TSH and high T4/3?
TSH oma (rare - pituitary disease secondary hyper/hypothyroidism)
What condition has low TSH and T4/3?
Pituitary gland failure
What refers to either severe hypothyroidism e.g. myxoedema coma or to accumulation of hydrophilic mucopolysaccharides in the ground substance of the dermis and other tissues-doughly induration of the skin classical seen in the shins = pretibial myxoedema which is seen in graves disease?
Myxoedema
Give two goitrous causes of primary hypothyroidism?
- Chronic thyroiditis - hashimotos thyroiditis (autoimmune)
2. Iodine deficiency
Name a drug which causes iodine deficiency?
Amiodarone, lithium, IL-2
Give four non-goitrous causes of primary hypothyroidism?
- Congenital developmental defect
- Atrophic thyroiditis
- Post-ablative (radioiodine)
- Postradiation
Give four hypothalmic causes of secondary hypothyroidism?
- Congenital
- Infection: encephalitis
- Infiltration: sarcoidosis
- Malignancy: craniopharyngioma
What is characterised by: presence of thyroid peroxidase antibodies in blood and T-cell infiltrate and inflammation on microscopy?
Autoimmune hypothyroidism aka Hashimoto’s thyroiditis
What intolerance do hypothyroidism patients have?
Cold intolerance
What type of fluid retention do hypothyroidism people get?
Pitting oedema
Give a cutaneous association wit hhypothyroidism?
Vitiligo
Name four cardiac symptoms of hypothyroidism?
- Reduced heart rate
- Cardiac dilatation
- Pericardial effusion
- Worsening of heart failure
Name one metabolic sign of hypothyroidism?
Hyperlipidaemia
Decreased appetite
Weight gain
Name three GI signs of hypothyroidism?
- Constipation
- Megacolon
- Ascites
Give three respiratory signs of hypothyroidism?
- Deep hoarse voice
- Macroglossia
- Obstructive sleep apnoea
What are these symptoms seen in: decreased intellectual and motor activities, dpression and psychosis, muscle stiffness, peripheral neuropathy and prolongation of tendon jerks?
Hypothyroidism
What condition of the wrist is seen in hypothyroidism?
Carpal tunnel syndrome
Give three gynaecology issues with hypothyroidism?
- Menorrhagia
- Later oligo-or amenorrhoea
- Hyperprolactinaemia - increase TRH causes, increase prolactin secretion
What is macrocytosis typical in and what should be ruled out?
Hypothyroidism and rule out a concurrent vitamin B12 deficiency
In hypothyroidism - is LDL cholesterol and CK increased or decreased?
Increased
What condition has 70-80% anti-TPO antibody, 30-50% anti-thyroglobulin antibody and 70-100% TSH receptor antibody?
Graves disease
What thyroid condition has 95% anti-TPO antibody, 60% anti-thyroglobulin antibody and 10-20% TSH receptor antibody?
Autoimmune hypothyroidism
What should be given to younger patients with hypothyroidism?
Thyroxine 50-100 ug daily
What should be given to elderly patients with IHD and hypothyroidism?
Thyroxine at 25-50ug daily, adjusted every 4 weeks to response
What should be checked in hypothyroidism patients adter 2 months of any dose change?
TSH
When might thyroxine (T4) doses by increased in a patient?
By 25-50% in pregnancy - increased TBG
What is the difference between primary and secondary hypothyroidism?
- TSH reflects tissue thyroid hormone actions in primary and it is not a useful in secondary as it will remain low if T4 therapy is commenced.
- TSH is an index of therapeutic success and potential toxicity in primary and T4 is used to monitor treatment in secondary.
What affects elderly women with long standing but frequently unrecognized or untreated hypothyroidism
Myxoedema coma
In relation to hypothyroidism - what does ECG: bradycardia, low voltage complexes, varying degrees of heart block, Twave inversion and prolongation of QT interval suggest?
Myxoedema coma
Name two cardiac symptoms and two sympathetic symptoms of hyperthyroidism?
1, Palpitations/AF
- Cardiac failure
- Tremor
- Sweating
Give three vision symptoms of hyperthyroidism?
- Lid retraction
- Double vision
- Eyes that bulge out or protrude in patients with Graves
What happens to menstrual cycle in hyperthyroidism?
- Lighter bleeding and less frequent periods
Name an autoimmune cause of Hyperthyroidism?
Graves disease
Name two nodular thyroid causes of hyperthyroidism?
- Multinodular goitre
2. Toxic nodule
Name two thyroiditis (inflammation) causes of hyperthyroidism?
Subacute and post-partum
Name two medications and one supplement which cause hyperthyroidism (iodine causes)?
Amiodarone, thyroxine and kelp
What antibody is positive in Graves?
TRAbs - TSH receptor antibody
What test other than TSH and antibody positive is used for Graves?
- Smooth symmetrical goitre - scintigraphy - high uptake/ultrasound
What is Graves natural progression?
At 18 months 50% will have burnt out and 50% will relapse
What do lid retraction, lid lag, chemosis, proptosis, visual loss and diplopia signs of?
Graves
What cause of hyperthyroidism are older patients more likely to get
Nodular thyroid disease
Name two tests other than TSH that are used for Nodular thyroid disease?
- Antibody negative TRAbs
2. Assymetrical goitre
How is a thyroid storm treatd?
- Lugols iodine
- Glucocorticoids
- PTU
- B-blockers
- fluids and monitoring
Name two medications used to treat hyperthyroidsim?
- Carbimazole
2. Propylthiouracil (preferred in pregnancy)
What is there a risk of with medication for hyperthyroidism?
Agranullocytosis
What can be used to treat symptoms in hyperthyroidism?
Beta-blockers
What type of thyroiditis is viral triggered and may be associated with throat/fever/other viral symptoms?
De Quervains
What tests are there for De Quervains/ sub-acute thyroiditis?
- T4- high in early stage, low in late
- TSH - low in early stage, high in late
- Scintigraphy Scan - low uptake
What areas does amiodarone induced thyrotoxicosi occur more frequently in?
Low iodine intake
What areas does amiodarone induced hypothyroidism occur more frequenly in?
High iodine intake
What embryological thyroid abnormalities result from failure of descent? excessive descent? thyroglossal duct cyst?
Linguial thyroid
Retrosternal location in mediastinum
thyroglossal duct cyst
What is the thyroid composed of?
Follicles
What are each follcie surrounded by in the thyroid?
Flat to cuboidal follicular epithelial cells
What is in the centre of each follicle?
Thyroglobulin
What cells present in the thyroid are large with a clear cytoplasm, secrete calcitonion and reult in lower serum Ca levels?
Parafollicular C cells
What do polymorphisms in CTLA-4 nad PTPN-22 cause?
Autoimmune thyroditis
What are the triad of features in graves disease?
- Hyperthyroidism with diffuse enlargement of the thyroid
- Eye changes
- Pretibial myxoedema
What two anti-thyroid antibodies are found in hashimotos thyroiditis#?
- Anti-thyroglobulin
2. Anti-peroxidase
In Hashimotos thyroiditis = what cells may mediate destruction of thyroid epithelium?
CD8+
What do orphan ani nuclei make the diagnosis of?
Papillary carcinoma
What does a medullary carcinoma come from?
C cell hyperplasia
What is parathyroid composed of?
Chief cells - secrete PTH, act on Ca homeostasis
What is the parathyroid supported by?
Oxyphil cells - slightly larger cells with acidophilic cytoplasm
What does chronic hypocalcaemia cause?
Compensatory over activity of parathhyroid glands
What type of hperparathyroidism is associated with hypercalcaemia?
Tertiary
What do bone disease, nephrolithiasis (stones), constipation, depression and weakn ess and fatigue suggeest?
Hyperparathyroidism
What might suggest hypoparathyroidism on ECG?
Prolonged QT interval
What are the three key events in ovarian cycle?
- Follicular growth
- Ovulation
- Luteal function
What hormone is produced when follicle is present in pregnancy?
Oestradiol
What hormone is produced when follicle is implanted in pregnancy?
HCG - pregnancy test
What hormone is released when corpus luteum is left in pregnancy?
Progesterone
What hormone is released when placenta is in place during pregnancy?
Human Placental Lactogen
What hormone does pituitary release in pregnancy?
Prolactin
What two hormines increase insulin resistance in the mother?
- Progesterones
2. Human Placenta Lactogen
When does gestational diabetes usually come?
In last third of pregnancy
When does foetal organogensis start?
At 5 weeks
Name three complications of gestational diabetes?
- Macrosomia
- Polyhydramnios
- Intrauterine death
Name three complications of type I and II diabetes in pregnancy?
- Congenital malformation
- Prematurity
- Intra-uterine growth retardation
What does foetal hyperinsulinemia lead to?
Macrosomia
What two drugs should be avoided in type I and Ii diabetic prenancy management>
- Statins
2. ACE inhibitors
Name a drug used to treat MODY?
Glibenclamide
What should be done 6 weeks post natal in gestational diabetic patients?
Glucose tolerance testing
If you get gestational diabetes what are the chances of becoming type II diabetic after 10-15 years?
50%
Name a good drug to control blood pressure in gestational diabetes?
Methyldopa
What causes anovulatory cycles?
Hypo/hyperthyroidism
What can HCG lower and increase in pregnancy?
Low TSH and increase fT4
What does a high HCG in pregnancy cause?
Morning sickness and extreme vomiting
Does the thyroid get bigger in pregnancy?
Yed
In a hypothyroidism pregnant patient - what levels should TSH be aimed for in first trimestter and second/third?
First -
What do TSH and HCG do to thyroxine?
Increase it
What condition in pregnancy causes infertility, spontaneous miscarriage, stillbirth, thyroid criss in labour and transietn neonatal thyrotoxicosis?
Hyperthyroidism
If using drugs to treat hyperthyroidism in pregnancy - what two should be used and when?
Propylthiouracil in first rimester
Carbimazole in second and third
Give some complications of carnbimazole?
- Scalp abnormalities
2. Choanal anf oesophageal atresia
Give two complications of propylthiouracil?
1.rISK OF LIVER TOXICITY
What is caused when TRAb antibodies cross the placenta?
Neonatal transient hyperthyroidism
Name two hormones released from hypothalamus and stored in posterior pituitary?
- vASOPRESSIN
2. Oxytocin
What does CRH cause release of in the pituitary?
ACTH
What does TRH cause release of in the pituitary?
TSH
What does GnRH cause release of in pituitary?
LH/FSH
What does GHRH cause release of in the pituitary?
GH
What does DA cause release of in pituirtary?
PRL
What hormones pair with LH/FSH in the peripheral?
Testosterone or estradiol
What hormone pairs with GH in peripheral?
IGF-1
Name a dynamic pituitary test?
Insulin Stress Test
In a water deprivation test if ur/serum osmol ration is >2 what does it mean?
Normal
What dynamic pituitary function test would you do (stimulation_ of IHD patients?
Prolonged glucagon test
What is the cause of compression on optic chiasm, compression on cranil nerves, hypoadrenalism, hypothyroidism, hypogonadism, DI and GH deficiency?
Non functioning pituitary adenoma
What does dopamine inhibit?
PROLACTIN
Name a dopamine antagonist which raises prolactin?
Metoclopramide
Do antidepressants raise prolactin?
YES
Name three pathological causes of raised prolactin?
- Hypothyroidism
- Stalk lesions
- Prolactinoma
Do females or males present first with prolactinoma?
Females first
What does galactorrhoea, menstrual irregularity, ammenorrhoea and infertility suggest?
Prolactinoma
What drugs are used to treat prolactinoma?
Dopamine agonists- bromocriptine, quinagolide and cabergoline
Name two local pituitary effects acromegaly patients get?
Visual fields and hypopituitarism
What are two tests for acromegaly?
IGF-1 and GTT
What are cabergoline, octreotide and pegvisomant used to treat?
Acromegaly
What drugs used in acromegaly reduce GH in mosy patients?
Somatostatin analogues
Name a few side effects of somatostatin analogues?
- Local stinging
- Flatulemce, diarrhoea, abdo pain
- Gastritis
- Gallstones
Name a GH antagonist used in acromegaly?
Pegvisomant - last line as so expensive