pathology of pituitary and adrenal Flashcards
where is the anterior pituitary gland derived from?
rathke’s pouch
what is secreted from the anterior pituitary?
TSH, ACTH, FSH, LH
GH and Prolactin
what is secreted from the posterior pituitary?
ADH (vasopressin) and oxytocin
what causes hyperfunction of the anterior pituitary?
Adenoma
Carcinoma
what causes hypofunction of the anterior pituitary gland?
Surgery/radiation
Sudden Haemorrhage into gland
Ischaemic necrosis
-Sheehan Syndrome
Tumours extending into sella
Inflammatory conditions (Sarcoidosis)
what is the most common pituitary adenoma?
prolactinoma
what are the symptoms of prolactinoma?
Infertility, lack of libido, amenorrhea (25% amenorrhoea)
what do growth hormone secreting adenomas do?
Stimulates growth of bone, cartilage and connective tissue
what are the symptoms of a growth hormone adenoma?
Gigantism or acromegaly
what is seen in an ACTH secreting tumour?
Cushing’s disease – wide range of signs and symptoms
Usually a micro-adenoma
Bilateral adrenocortical hyperplasia
what are the features of craniopharyngioma?
Slow growing, often cystic, may calcify
Some arise within the sella but most suprasellar
Bimodal incidence
5 -15 years age
6th – 7th decades
what are the symptoms of a craniopharyngioma?
headaches and visual growth disturbance
(children may have growth retardation)
true or false, craniopharyngioma have a poor prognosis
False
excellent prognosis esp if <5cm
what is an example of a posterior pituitary syndrome?
diabetes insipidus
what causes diabetes insipidus?
ADH deficiency
Trauma (including surgery), tumours and inflammatory disorders of hypothalamus and pituitary
are adrenal glands bilateral?
yes
where are the adrenal glands?
sit superiorly and medially to the upper pole of the kidneys
what are the three zones of the adrenal gland cortex?
zona glomerulosa
zona fasciculata
zona reticularis
what is secreted from the zona glomerulosa?
Mineralocorticoids
Aldosterone
what is secreted from the zona fasciculata?
Glucocorticoids
Cortisol
what is secreted from the zona reticularis?
sex steroids
glucocorticoids
what is the medulla of the adrenal gland?
the central core
what is the medulla innervated by?
pre-synaptic fibres from sympathetic nervous system
what do neuroendocrine (chromaffin) cells secrete?
secrete catecholamines
who is usually affected by adrenocortical tumours?
mainly adults
males and females are affected equally
how do adrenocortical tumours usually present?
Incidental finding (radiology, autopsy)
Hormonal effects
Mass lesion
Carcinomas with necrosis can cause fever
which is more common, an adrenocortical carcinoma or adenoma?
adenoma
what are features suggestive of an adrenocortical carcinoma?
Large size (>50g, often >20cm)
Haemorrhage and necrosis
Frequent mitoses, atypical mitoses
Lack of clear cells
Capsular or vascular invasion
what are the symptoms of addisons disease?
Weakness, fatigue, anorexia, nausea, vomiting, weight loss, diarrhoea
Pigmentation (raised POMC) – not seen in hypopituitarism
does addisons disease decrease mineral corticosteroids?
yes
Hyperkalaemia, hyponatraemia, volume depletion and hypotension
what does addisons crisis look like?
Stress – infection, trauma, surgery
Vomiting, abdominal pain, hypotension, shock and death
when is a neuroblastoma ususally diagnosed?
18 months, 40% diagnosed in infancy
what % of neuroblastomas arise in the adrenal medulla?
40%
what predicts a poor outcome in a neuroblastoma?
Amplification of N-myc & expression of telomerase predict a poor outcome
what is the 10% tumour?
phaeochromocytoma
why is phaeochromocytoma known as the 10% tumour?
10% are extra adrenal
10% are bilateral
10% are biologically malignant
10% are not associated with hypertension
what % of phaeochromocytoma are familial?
25%
