Cushings and Hypopituitarism Flashcards Preview

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Flashcards in Cushings and Hypopituitarism Deck (37)
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1
Q

Screening Tests for Cushings

Definitive Tests for Cushings

A
Screening:
-1mg dexamethasone suppression test
-Urine free cortisol test (<250 is normal)
-Diurnal cortisol variation
Definitive:
2 day 2mg/day dexamethasone
2
Q

Aetiology of Cushings

A
Pituitary (80% plus)
Adenoma of adrenal
Benign
cancer
Ectopic
Thymus
Lung
Pancreas
Pseudo
Alcohol and Depression
Steroid medication
3
Q

When treatng cushings, what would you do if hypophysectomy did not work?

A

External radiotherapy

4
Q

How would you treat ectopic cushings?

A

Bilateral adrenalectomy if you cannot find source etc

5
Q

Drug treatment for cushings if other treatment does not work

A

Metyrapone- if other treatments fail - while waiting for radiotherapy to work- S/E common
Ketoconazole
Pasireotide- new somatostatin analogue

6
Q

Autoimmune causes of hypopituitarism

A

Sheehans

7
Q

Secondary metastatic lesions that could cause hypopituitarism

A

Breast, lung

8
Q

Local brain tumours

A

Astrocytoma
Meningioma
Glioma

9
Q

Granulomatous diseases that could cause hypopituitarism

A

TB
Sarcoidosis
Histiocytosis X

10
Q

Vascular disease that could cause hypopituitarism

A

Polyarteritis

11
Q

Hypothalamic diseases that could cause hypopituitarism

A

Syphilis

Meningites

12
Q

Causes of hypopituitarism

A
Pituitary Tumours
Secondary metastatic lesions
lung, breast
Local brain tumours
Astrocytoma, meningioma, glioma
Granulomatous diseases
TB, Histiocytosis X, sarcoidosis
Vascular diseases
Polyarteritis
Trauma
road accidents, skull fractures
Hypothalamic diseases
Syphilis, meningitis
Iatrogenic; surgery
Autoimmune;Sheehan – post pregnancy
Infection; meningitis
13
Q

Signs and symptoms of anterior hypopituitarism

A
Menstrual irregularities (F)
Infertility, impotence
Gynaecomastia (M) (testosterone deficiency)
Abdominal obesity
Loss of facial hair (M)
Loss of axillary and pubic hair (M&F)
Dry skin and hair
Hypothyroid faces
growth retardation (children)
14
Q

Testing for Hypopituitarism

Baseline pituitary function tests

A

fT4, TSH
Oestradiol/Testosterone, LH FSH
GH, IGF-1
Prolactin

15
Q

Replacement therapy for hypopituitarism

A
Thyroxine		 100-150mcg/day
Hydrocortisone 10-25 mg/day (am/pm)
ADH			 Desmospray (nasal) or tablets
GH			 GH nightly sc
Sex Steroids	 Oest/prog pill for F, Testosterone for males
16
Q

Growth hormone and bone density?

A

GH increases bone density

17
Q

Growth hormone and muscle mass?

A

GH increases muscle mass, strength, exercise capacity and stamina

18
Q

GH and abdominal obesity

A

GH decreases abdominal obesity

19
Q

GH and cardiac function

A

GH improves cardiac function

20
Q

GH and cholesterol and LDL

A

Decreases cholesterol and LDL

21
Q

How is GH administered?

A

Daily by subcutaneous injection

22
Q

Testosterone replacement

A
IM injection every 3-4 weeks (sustanon)
Skin gel (testogel, tostram)
Prolonged IM injection 10-14 wks (nebido)
(Oral tablets (restandol))
23
Q

Intramuscular injection that can be given as testosterone replacement?

A

Sustanon

-Given every 3-4 weeks

24
Q

Restandol is an oral testosterone replacement. What are the risks of tablet oral testosterone?

A

Hepatitis

25
Q

Risks of Testosterone Replacement

A

Prostate Enlargement. Does NOT cause prostate cancer but may make it grow - monitor PR exam and PSA
Polycythaemia - monitor FBC
Hepatitis (only for oral tablets) - monitor LFTs

26
Q

Causes of Cranial Diabetes Insipidus

A
Familial
isolated in most cases
DIDMOAD  (DI, DM, optic atrophy, deaf)
Acquired
Idiopathic in 50%
Trauma; road accidents, surgery, skull fracture
RARE
Tumour, sarcoid, ext irradiation, meningitis
27
Q

Most common type of pituitary gland tumour

A

Prolactinoma

28
Q

Symptoms of a prolactinoma

A

Headaches or reduced vision if prolactinoma is pressing on brain or nerves nearby

Irregular periods or no periods.
Reduced fertility.
Reduced sex drive.
Milk leaking from the breasts (known as galactorrhoea). The milk may leak out by itself, or may only show when the breast is squeezed. (Note: leakage of milk from the breasts is normal towards the end of pregnancy, with recent childbirth, if breast-feeding, and for some time after finishing breast-feeding.)
Increased growth of hair on the face or body.

MEN may have:
Reduced fertility.
Erectile dysfunction (difficulty having an erection).
Reduced sex drive (libido).
Breast enlargement (called gynaecomastia).
Very rarely, leakage of milk from the breasts.

29
Q

Normal levels of prolactin

A

5000mU/L

30
Q

Drugs that can increase prolactin levels

A

Risperidone, clopramide, domperidone

31
Q

Somatostatin and GH

A

Somatostatin analogues are currently used as treatment for GH acromegaly, they may also be used to shrink large tumours before surgery. They are synthetic analogues of somatostatin which inhibits GH production
-Injected every 2-4 weeks for effective treatment

32
Q

What type of receptor does TSH bind to?

A

Surface receptors
This then activates G proteins and conversion of GTP to GDP and production of cAMP
cAMP increases production and release of T3 and T4
T3 and T4 circulate in bound and free forms

On release T3 and T4 bind to receptor in target cells.
Complex translocates to the nucleus
Binds to Thyroid Response Elements on target genes
Stimulates transcription of these genes
Increase BMR

33
Q

Struma ovarri

A

“goitre of the ovary”

Contains thyroid tissue

34
Q

Can you get a TSH secreting adenoma?

A

Yes, but rare

35
Q

Causes of hyperthyroidism

A

Symptoms and signs occur as a result of excess T3 and T4
85% are due to Grave’s disease
Other causes include hyperfunctioning nodules/tumours and thyroiditis
TSH secreting pituitary adenoma (rare)
Ectopic production (struma ovarii)
Factitious (exogenous intake)

36
Q

DeQuervains Thyroiditis

A

De Quervains Thyroiditis: hyperthyroid then hypothyroid, euthyroid. Patients may suffer dysphagia. There are multi-nucleated giant cells on histology

37
Q

Difference between thyroiditis and Graves disease in radionucleotide isotope uptake?

A

Thyroiditis = decreased uptake

Graves disease = increased uptake