2. PITUITARY DISORDERS
Pituitary tumours
ďPituitary tumors are responsible for most hormone abnormalities involving the
pituitary gland (PG) â Adenoma
ď3 histological types of pituitary tumour, all âadenomasâ.
ďMost (80% are benign)
ďThe pituitary lies directly below the optic chiasma
ďPituitary tumours tend to grow upwards â OCULAR COMPLICATIONS
ďA pituitary tumor can cause the (PG) to produce too much or too few
hormones, which can cause problems in the body.
ďPituitary tumours may produce illness by:
1.Local pressure related to size and location
2.Secretion of hormones in unusual amounts
3.Hypopituirism
3. ACROMEGALY/GIGANTISM
ďRare -hypersecretion of growth hormone (GH) by Somatotrophs ( a growth
hormone achieves development of the human body). These are released
by the Pituitary Gland
ďUsually forms a pituitary adenoma.
ďAffects - 20 and 40 years of age.
ďAcromegaly: hypersecretion during adulthood â overgrowth of bone and
tissue
ďGigantism: hypersecretion during childhood â induced skeletal (bone) growth
still maintaining normal shape and proportion
4. Clinical Features
ďIncrease in size of skull
ďThick, spade shaped fingers, increasing shoe size and vertebral enlargement
ďEnlarged tongue, heart, liver and thyroid.
ďHeadache (the dura is stretched as skull enlarges).
ďVoice deepens.
ďHypertension , heart failure, diabetes, joint pain, proximal muscle weakness may
also develop.
5. ACROMEGALY/GIGANTISM
Management:
ďDestruction of the tissue producing the excess
hormone.
ďThe choice between surgery, external irradiation and
radioactive implant depends on the age and health of
the patient.
ďUntreated, the life expectancy of a person with
acromegaly is halved.
ďBromocriptine reduces GH levels -useful additional
treatment.
6. Hyperprolactinaema
ďStimulates breast development and milk production in women.
ďCommonest condition caused by pituitary dysfunction
ďPatients usually presents to the gynaecologists in the guise of
menstrual disturbance, and infertility.
ďProlactin is a Hormone secreted by the Pituitary gland for production of
milk. It goes with the name lactose. It is found in both male and
females.
ďIncreased blood prolactin levels also produce acne, galactorrhoea,(milk
discharge from nipples) â libido and (in males) impotence.
7. Hyperprolactinaema
Other causes of â prolactin are:
ďPregnancy, breast feeding, stress and sleep
ďDrugs- phenothiazines and haloperidol (used in control of psychosis),
methyldopa and oestrogens.
ďChronic renal failure
Management:
ďDepends on underlying cause.
ďBromocriptine or Cabergoline
ďSurgery +/â radiation
ďThese tumours are very slow-growing and sometimes require no
treatment
8. Cushing Syndrome
Hypersecretion of cortisol
⢠Presents with:
â Hypertension
â Obesity
â Diabetes
â Skin marks (striate)
â Excess body and facial hair
â Alterations in mental function
10. Hypopituitarism
Under-activity of the pituitary gland.
Aetiology:
ďSurgery.
ďRadiation.
ďAdenoma.
ďPost partum (after giving birth) haemorrhage.
ďSecondary malignancy.
11. Anterior Pituitary Hypofunction
⢠Failure of pituitary secretion may affect one or several
hormones: Lack of:
â TSH: Hypothyroidism
â Prolactin: Hyperprolactinemia
â ACTH ( adrenocorticotropic Hormone)
â Gonadotrophin
12. Anterior Pituitary Hypofunction:
Hypoprolactinemia
Clinical features:
ďInability to lactate
ďChildren â âPeter Panâ dwarfism (look young when old).
ďAdults â A variety of hormone problems including menstrual
disturbance, adrenal insufficiency, hypothyroidism and decreased
body hair.
Treatment:
ď Hormone replacement (e.g. âthe pillâ, cortisone, thyroxine).
13. Thyroid disease
ďThe thyroid gland and the pituitary gland work together.
ďThe pituitary âmaster gland,â - makes, stores, and releases thyroid-
stimulating hormone (TSH)- tells the thyroid how much hormone
triiodothyronine (T3) thyroxine (T4) .
ďIodine from blood (diet) + tyrosine (amino acid) by action of TSH produce
T3 and T4
ďThyroid hormones affect every cell and all the organs of the body.
14. Function of T3 +T4
1.Controls the rate of metabolism. : â basal metabolic rate (BMR)
2.Slows down or speed up your heartbeat.
3.Raises or lowers your body temperature.
4.Change how fast food moves through your digestive tract.
5.Affect muscle strength.
ďToo much thyroid hormone speeds things up and too little thyroid hormone
slows things down.
16. Types
of Thyroid
lesions
Graves Disease :
â˘Toxic Nodular Goitre < 10%
â˘Toxic Adenoma < 5%
â˘Acute or painless
thyroiditis: inflammation
of the thyroid gland due
either to virus or taking
too much of thyroid
hormone in tablet form
17. OCULAR MANIFESTATIONS
ďAutoimmune attack specifically on the eye muscles and
connective tissues within the socket
-tissues contain protein like those found in the immune system
ďCauses inflammation
⢠Swelling of muscles and surrounding tissue
⢠Restricted eye movement
⢠Pain
⢠Eyes bulge forward â Proptosis
⢠2° complications
⢠May impinge on the Optic Nerve
⢠Blurred vision
18. Hypothyroidism
Ocular signs
ď Usually, rare
ďLoss of lateral 1/3 of eyebrow
ďPeri-orbital oedema
1.Decrease TSH - increase in mucus like protein deposit in the deeper skin
2.Resolves with treatment
ďPtosis
1.Decrease TSH decreases nerve stimulation of eyelids - drooping
ďLenticular opacities
ďKCS
19. Adrenal Glands
ďItâs the structure on top of kidney
Adrenal gland:
ď§ Adrenal medulla secretes adrenaline and noradrenaline
(catecholamines).
ď§ Adrenal cortex produces 3 steroid hormones (corticosteroids):
1. Glucocorticoids (cortisol) which raise blood sugar, antagonize
insulin, facilitate the action of catecholamines on the heart and
blood vessels, supress the inflammatory response, break down
protein, reduce the white cell count and cause sodium retention and
potassium loss.
2. Mineralocorticoids (aldosterone) which cause sodium retention
and potassium loss.
3. Repro. hormones-testosterone and oestrogens.
20. Adrenal Disorders
Disorders of the adrenal cortex
Clinical features include:
⢠Moon face
⢠Acne
⢠Fat body Âą âbuffaloâ hump on back
⢠Muscle weakness
⢠Purple stretch marks (striae) on abdomen, thighs and buttocks (ânormalâ stretch marks are pink)
⢠Easy bruising
⢠Osteoporosis (leading to back ache and, sometimes, vertebral collapse)
⢠Diabetes, Hypertension,
⢠Sodium retention, Potassium loss
⢠Kidney stones,
⢠Mental disturbance,
⢠Masculinization of females
21. Disorders of the adrenal medulla
ďąNeuroblastoma - Cancer of immature nerve cells arising from the adrenal gland,
nerve ganglia or the neck. This causes abdominal pain, diarrhea or constipation,
lumps of tissue under the skin, wheezing and weight loss.
ďąPheochromocytoma
⢠Tumour mainly of adrenal medulla or extra-adrenal tumour around
sympathetic ganglia.
⢠Produces excess adrenaline.
⢠Remember: adrenaline maintain normal BP and helps us cope with stressful
situations
⢠Clinical manifestation reflect:
⢠elevated circulating catecholamines.
⢠90% of these patients have dramatic hypertension in the region
220/150mHg.
⢠May present retinal and cerebellar haemangiomas
22. Symptoms of Medulla disorder
ďheadaches,
ďsweating,
ďracing heart( tachycardia and palpitations),
ďnausea,
ďweight loss
ďheat intolerance
ďSurgery is definitive treatment