PHARM 7 Therapy of Pituitary/Adrenal Disease

Question 1

________________:peripheral visual field loss due to compression of optic chiasm by pituitary gland mass

Answer 1

Bitemporal Hemianopia: peripheral visual field loss due to compression of optic chiasm by pituitary gland mass

Question 1

________________: Sudden pituitary mass effect due to bleed into infarct leading to sudden vision loss, severe headache, bitemporal hemianopia

Investigations/Treatment?

Answer 1

Apoplexy: Sudden pituitary mass effect due to bleed into infarct leading to sudden vision loss, severe headache, bitemporal hemianopia

Investigations:

• MR pituitary
• Investigate for hormone deficiencies

Treatment: IV hydrocortisone (URGENT)

Question 2

Complications of Pituitary Surgery?

Answer 2

• Hypopituitarism: ALWAYS hydrocortisone cover peri-/postop
• Hypothalamic damage (LARGE Pituitary tumour) => Hypothalamic Obesity (Obesity in 2/3 craniopharyngioma post-op)
• Diabetes Insipidus (Deficiency of ADH- Vasopressin; Polyuric (pee a lot))

Question 3

Sequence of hormonal failure in Hypopituitarism?

Answer 3

First LH/FSH /GH deficiency

Then ACTH, TSH +/- ADH deficiency

Question 4

Consequences of LH/FSH deficiency? (Anterior Hypopituitarism)

Therapy?

Answer 4

central / secondary hypogonadism

• If fertility pursued, injectable / pump gonadotropins
• If not, sex steroid replacement – note safety monitoring (Increase in EPO)

Question 5

Consequences of TSH deficiency? (Anterior Hypopituitarism)

Answer 5

Secondary hypothyroidism

Treated with T4 (thyroxine) replacement

Question 6

Consequences of ACTH deficiency? (Anterior Hypopituitarism)

Answer 6

Central Adrenal Insufficiency

Treated with Hydrocortisone (glucocorticoid)

Question 7

Pathogenesis/Diagnosis of Diabetes Insipidus?

Answer 7

Posterior pituitary damage: AVP reduced; urine dilute

1) Polyuria (>3 litres urine per day)

2) Polydipsia

3) Hypernatremia & increased serum osmolality if cannot drink enough to replace losses

Diagnosis: dilute urine & concentrated plasma (cannot measure AVP)

Question 8

Consequences of Pituitary Hormone Excess?

ACTH –___________________

GH – ____________________

LH / FSH – Very rare! Might cause amenorrhea

TSH – Leads to secondary thyrotoxicosis. Very rare!

Prolactin – _______________

Answer 8

ACTH – Inc cortisol levels (Cushing’s disease)

GH – Inc GH & IGF-1 levels (Gigantism / Acromegaly)

LH / FSH – Very rare! Might cause amenorrhea

TSH – Leads to secondary thyrotoxicosis. Very rare!

Prolactin – (MOST COMMON) Leads to galactorrhoea, amenorrhoea, infertility, ED

Question 9

Diagnosis of Cushing’s Disease?

Answer 9

Detected by:

• high cortisol production
• loss diurnal rhythm of cortisol
• loss of negative feedback of glucocorticoids on pituitary

Pituitary origin: ACTH levels will be detectable

Question 10

Pathogenesis of Gigantism / Acromegaly?

Symptoms/Clinical Features?

Answer 10

GH excess leads to increased Insulin-like Growth Factor-1 production by liver

Both GH and IGF1 increase growth of a range of soft & hard tissues

> 98% due to a pituitary tumour, often large

Question 11

Diagnosis/Treatment of Gigantism/Acromegaly?

Answer 11

Diagnose:

• Oral Glucose Tolerance Test
• OGTT also reveals pre-diabetes and diabetes for which acromegaly is a risk factor

Medical Treatment:

• Dopamine agonists: (cabergoline / bromocriptine); hypotension, valvulopathy in long term high dose cases (>3mg/week)
• Somatostatin analogues (somatostatin natural inhibitor of GH production). Monthly injection. GI S/Es, inc glucose, gallstone formation
• GH receptor antagonist (Pegvisomant). Daily injection; cannot use for tumour size control, v expensive

Surgery – debulks large tumours; risk new hormone deficiency

Radiotherapy – effect delayed

Question 12

Management of Hyperprolactiemia?

Answer 12

• MRI scan to rule out macroadenoma
• Treated medically with dopamine agonists
• Prolactinoma patients don’t need surgical referral EVEN IF MASS EFFECT SIGNS
• Remember: cover with hydrocortisone until cortisol level back from lab

Question 13

General Approach to Piuitary Management?

Answer 13

Asses for Mass Effects: Physical exam, MRI

Asses for Hormone Deficiency

Cover with Hydrocortisone

Question 14

Adrenal Insufficiency (aka, ______________) Hormones Impacted/Clinical Presentation?

Answer 14

Adrenal Insufficiency (aka, Addison’s Disease)

Hormones Impacted

• Low Cortisol
• Low Aldosterone
• High ACTH

Presentation

• Collapse
• Hyponatremia w/ Hyperkalemia
• Hyperpigmentation
• Hypoglycemia

Question 15

Treatment of Hypoadrenalism (Addison’s Disease)?

Answer 15

IV Hydrocortisone => Oral

Replace Fluids

Sick Day Rules: Double if Temp/Antibiotics

Question 16

Management of Adrenal Lesions?

Answer 16

Cortisol Producing: Hydrocortisone pre/post op

Aldosterone Producing: Pre-op Spironolactone

Pheochromocytoma: Pre-Op Alpha Blockade

Question 17

Adrenal Syndromes?

Answer 17

Conn’s (Hyperaldosterone): Hypertension and Hypokalemia

Cushing’s (Hypercortisolism): Weight gain and more body fat

Androgen Excess (DHEA): Virilization of females

Pheochromocytoma (Grows from chromaffin cells=> excess epinephrine/norepinephrine): Hypertension, Flushing/Sweating, Anxiety/Panic