Cushings, hypopituitarism and diabetes insipidus

Question 1

What is cushings syndrome?

Answer 1

Excess cortisol

Question 2

What are the clinical manifestations of protein loss in cushings?

Answer 2

Proximal myopathy
Osteoporosis
Thin skin: striae, bruising

Question 3

What are the clinical manifestations of altered carb/lipid metabolism in cushings?

Answer 3

Diabetes mellitus

Obesty

Question 4

What are the clinical manifestations of altered psyche in cushings?

Answer 4

Psychosis

Depression

Question 5

What are the clinical manifestation of excess mineralocorticoid activity in cushings?

Answer 5

Hypertension

Oedema

Question 6

What are the clinical manifestations of excess androgen production in cushings syndrome?

Answer 6

Virilism
Hirsutsm
Acne
Oligo/amenorrhoea

Question 7

How can you differentiate cushings from obesity?

Answer 7

Cushings: 
Thin skin
Proximal myopathy
Frontal balding
Conjunctival oedema
Osteoporosis

Question 8

What is the test for cushings?

Answer 8

Exogenous dexamethasone which in normal people would result in a low serum cortisol

Question 9

What are the screening tests for cushings?

Answer 9

Overnight 1mg dexamethasone suppression test: cortisol >100nmol/l cushings
Urine free cortisol (24hr urine collection): >250 abnormal, cortisol/creatinine ration >25 normal
Diurinal cortisol variation (midnight/8am)

Question 10

What is the definitive test for cushings?

Answer 10

2 day 2mg/day dexa test

Cortisol >130, defos cushings

Question 11

What is the aetiology of cushings syndrome?

Answer 11

Pituitary adenoma - cushings disease
Adenoma of adrenal gland
Ectopic ACHT production (thymus, lung and pancreatic cancer)
Pseudo - alcohol and depression, steroid medication

Question 12

What will cushings syndrome of pituitary origin (cushings disease) show upon tests

Answer 12

Abnormal low dose dexa test
ACTH <300
Suppression by 50% of high dose dexa test

Question 13

What will cushings syndrome of adrenal origin show upon tests?

Answer 13

Abnormal Low dose dexa test
ACTH levels <1
No suppression upon high dose dexa test

Question 14

What will cushings syndrome of ectopic ACTH origin show upon tests?

Answer 14

Abnormal low dose dexa test
ACTH >300
No suppression on high dose dexa test

Question 15

What will the CRH test show in cushings disease?

Answer 15

50% increase in ACTH

20% increase in cortisol

Question 16

What is the treatment of cushings disease?

Answer 16

Hypophysectomy and external radiation if recurs

Bilateral adrenalectomy

Question 17

What is the treatment of cushings syndrome of adrenal origin?

Answer 17

Adrenalectomy

Question 18

What is the treatment of cushings syndrome of ectopic ACTH origin?

Answer 18

Removal or source e.g. SCC of lung

Bilateral adrenalectomy

Question 19

What is the drug treatment for cushings?

Answer 19

Metyrapone (acts on steroid axis) if surgery fails or whilst waiting for radiotherapy to work

Question 20

What are common S/E of metyrapone?

Answer 20

N+V
Dizziness
Headache
Hypotension 
Sedation

Question 21

What other drug treatments are avaliable if metyrapone fails?

Answer 21

Ketoconzaole

Pasireotide LAR which is a somatostatin analogue

Question 22

What can result from panhypopituitarism?

Answer 22

Ant pit: 
GH (growth failure) 
TSH (thyroidism) 
LH/FSH (hypogonadism) 
ACTH (hypoadrenal) 
Prolactin
Post Pit: 
Diabetes insipidus

Question 23

What can cause hypopituitarism?

Answer 23

Pituitary tumours
Secondary met lesions (lung, breast)
Local brain tumours (astrocytome, meningioma, glioma)
Granulomatous disease (TB, histocytosis, sarcoidosis)
Trauma (RTA, skull fracture)
Hypothalamic disease (syphilis, meningitis)
Iatrogenic; surgery
Autoimmune; sheenan
Infection; meningitis

Question 24

What are symptoms and signs of anterior hypopituitarism?

Answer 24

Menstrual irregulatities
Infertility, impotence
Gynaecomastic
Abdominal obesity
Loss of facial hair
Loss of axillary and pubic hair
Dry skin and hair
Hypothyroid face (moon face) 
Growth retardation

Question 25

What tests are best for the steroid axis?

Answer 25

Synacthen test | Insulin tolerance test

Question 26

What should the levels of LH and FSH be like in post-menopausal women?

Answer 26

High and therefore if the levels are normal or low this suggest pituitary pathology

Question 27

What are the replacement therapies in place for hypopituitarism?

Answer 27

``` Thyroxine 100-150 mcg/day Hydrocortisone 10-25 mg/day ADH - desmospray or tablets Gh - GH nightly SC Sex steroids - HRT/Oest/Prog pill Testosterone for males ```

Question 28

What will GH do in adults?

Answer 28

``` Decreases abdo fat Increases muscle mass, strength and exercise capacity and stamina Improves cardiac function Decreases cholesterol and increases HDL Increases bone density ```

Question 29

What are risks of testosterone replacement?

Answer 29

Prostate enlargement Polycythaemia Hepatitis

Question 30

What should be performed prior to testosterone replacement therapy?

Answer 30

PR exam and PSA - makes prostate grow FBC for polycythaemia LFTs for hepatitis

Question 31

What can cause cranial diabetes insipidus?

Answer 31

Familal: isolated in most cases, DIDMOAD Acquired: idiopathic, RTA, surgery, skull fracture RARE: tumour, sarcoid, ext irradiation, meningitis

Question 32

What is DIDMOAD?

Answer 32

DI; diabetes insipidus DM; diabetes mellitus OA; optic atrophy D; deaf

Question 33

What is the treatment for DI?

Answer 33

Desmospray Desmopression oral tablets (100-1000mcg per day) Desmopressin injection (emergency or post pituitary surgery)