Histopath - Endocrine Flashcards
Hypothalamic- pituitary feedback axis
What are the 6 anterior pituitary hormones?
- Prolactin
- TSH
- ACTH
- GH
- FSH
- LH
Hyperpituitarism
Excess hormone secretion due to a functional adenoma (based on hormone secreted)
(Panhyperpituitarism also exists but rare)
Which type of functional adenoma is most common?
Prolactinoma
Prolactinoma presentation
- Amenorrhoea
- Galactorrhoea
- Loss of libido
- Infertility
GH adenoma presentation
- Gigantism or acromegaly
- DM, muscle weakness, HTN, CCF
ACTH adenoma presentation
Cushing’s syndrome
Cushing’s disease even - as coming from pituitary.
Most common type of hypopituitarism
Pan-hypopituitarism
Causes of hypopituitarism
- Non-secreting/functional pituitary adenoma (compression)
- Ischaemic necrosis
- Sheehan’s syndrome (bleeding into pituitary)
- DIC
- shock
- Iatrogenic
- Surgery
- Irradiation
(Pan-)hypopituitarism presentation
- GH deficiency
- Growth failure in children
- GnRH deficiency (V SIMILAR syx TO PROLACTINOMA)
- Amenorrhoea
- Infertility
- Decreased libido
- Impotence
- TSH and ACTH deficiency
- Hypothyroidism
- Hypoadrenalism
- Prolactin deficiency
- Failure of PP lactation
What can large pituitary tumours cause?
- Bitemporal hemianopia due to compression of optic chiasm
- Signs + syx of raised intracranial pressure
Which 2 hormones are secreted from the posterior pituitary?
Oxytocin and ADH
What does excess ADH release result in?
SIADH
Euvolaemic hyponatraemia
What does ADH deficiency result in?
Diabetes insipidus
- Absolute deficiency -> cranial cause*
- Resistance -> nephrogenic cause*
Hypothalamus - ant pit - thyroid axis
Hyperthyroidism presentation
- Weight loss (or gain)
- Increased sweating/heat intolerance
- Diarrhoea
- Nervousness/anxiety
- Light and short periods
Hypothyroidism presentation
- Cold intolerance
- Weight gain
- Constipation
- Depression and irritability
- Irregular and heavy periods
Hyperthyroidism causes
- Primary (issue with thyroid)
- Grave’s disease
- MOST COMMON
- Multinodular goitre/hyperfunctioning adenoma
- Thyroiditis (inflammed -> loads of thyroxine produced and then all released so hypo after)
- DeQuervain’s
- Viral
- Grave’s disease
- Secondary (issue with pituitary)
- TSH producing adenoma (rare)
- Other
- Exogenous thyroid intake
Iodide uptake scan results for Grave’s, multinodular and thryoiditis
- Grave’s: diffuse increased uptake
- Multinodular: one or multiple hot nodules
- Thyroiditis: no change
Grave’s disease presentation
- Thyrotoxicosis
- Exophthalmos
- Pretibial myxoedema
F>M, younger adults
Grave’s associated antibody
Anti-TSHr antibodies
Which autoimmune disorders are associated with Grave’s disease?
- SLE
- Pernicious anemia
- T1DM
- Addisons
Hypothyroidism causes
Primary
- Iatrogenic
- post treatment for hyperthyroidism
- Autoimmune -> Hashimoto’s
- Most common cause in UK
- 45-65y/o, F>M
- Painless enlargement
- Iodine deficiency
- Most common cause worldwide
Secondary
- Pituitary failure (rare)
What are the 4 types of thyroid carcinoma?
- Papillary
- Follicular
- Medullary
- Anaplastic
*Which thyoid carcinoma is most common?
Papillary
*Histopath of papillary thyroid carcinoma
Psammoma bodies
*Histopath of medullary thyroid carcinoma
From parafollicular C cells
*What syndrome is medullary thyroid carcinoma associated with?
MEN syndrome
*Which is the most aggressive type of thyroid carcinoma?
Anaplastic
Parathyroid functions + feedback loop
Responsible for Ca homeostasis
Hyperparathyroidism causes
- Primary
- Solitary adenoma > gland hyperplasia > carcinoma
- Secondary
- Most commonly due to renal failure
Biochemistry for primary and secondary hyperparathyroidism (PTH and Ca)
Primary: high PTH, high Ca2+
Secondary: high PTH, low Ca2+
Hyperparathyroidism presentation
Same as hypercalcaemia
- (Painful) bones
- (Renal) stones
- (Abdominal) groans
- (Psychic) moans
Hypoparathyroidism causes
- Iatrogenic
- Congenital absence
- Autoimmune
Hypoparathyroidism presentation
CATS
- Convulsions
- Arrhythmias
- Tetany
- Spasms
What are the 4 zones of the adrenal cortex? (From outermost)
- Zona glomerulosa
- Zona fasciculata
- Zona reticularis
Which hormones are released from the Zona glomerulosa?
Mineralocorticoids
e.g., Aldosterone
Which hormones are released from the Zona fasciculata?
Gluccocorticoids
e.g., Cortisol
Which hormones are released from the Zona reticularis?
Androgens
e.g., Dehydroepiandrosterone
Which hormones are released from the adrenal medulla?
Stress hormones
e.g., epinephrine/adrenalin
What is Conn’s syndrome?
Hyperaldosteronism due to
Aldosterone secreting adenoma (in adrenal)
Hyperaldosteronism causes
- Conn’s syndrome (aldosterone secreting adenoma)
- Bilateral adrenal hyperplasia (more common)
Hyperaldosteronism presentation
- Hypertension
- Hypokalaemia
- Aldosterone resp for secr potassium in urine
What is Cushing’s syndrome?
Too much cortisol
Causes of Cushing’s syndrome
- Exogenous
- MOST COMMON - toomuchsteroids
- Endogenous
- Cushing’s disease -> ACTH producing adenoma (in pituitary)
- Adrenal causes -> adenoma/carcinoma/bilateral hyperplasia
- Ectopic ACTH production -> small cell carcinoma of the lung
Cushing’s syndrome presentation
- Truncal obesity
- Moon facies
- Buffalo hump/ dorsocervical fat pad
- Cutaneous striae
- HTN
What happens to adrenals in 1) Cushing’s disease (/pituitary cushing syndrome), 2) Adrenal cushing syndrome, 3) paraneoplastic cushing syndrome, 4) iatrogenic/exogenous
- Adrenal hyperplasia
- Tumour, or nodular hyperplasia
- Adrenal hyperplasia
- Adrenal atrophy
Adrenal insufficiency causes
Acute
- Sudden withdrawal of long-term steroids
- Sepsis with DIC (Waterhouse-Friderichson syndrome)
- Insufficient blood supply -> ischaemic -> unable to produce hormones
- Haemorrhage
- Insufficient blood supply -> ischaemic -> unable to produce hormones
Chronic
- Autoiummune -> Addison’s
- Most common in the UK
- TB
- Most common worldwide
What is Addison’s?
Autoimmune adrenal insufficiency
What is a pathology of the adrenal medulla?
Phaeochromocytoma
What is phaeochromocytoma?
Excess catecholamine secretion (adrenaline, noradrenaline)
Phaeochromoctymoa presentation
- Resistant HTN
- Episodic palpitations
- Abdo pain
Often young pt
What is the rule of 10s in Phaeochromocytoma?
10% familial syndromes
10% bilateral
10% malignant
*Which thyroid ca most likely to spread via blood?
Follicular
