Acromegaly its causes and newest treatment

1. Physiology :

a. Hormone : G.H.

b. Gland : Pituitary gland.

c. Function of the hormone :

i. CHO : hyperglycemia.

ii. fat : lipolysis.

iii. protein : anabolic (bone, muscle & viscera).

iv. minerals : ↑ all i minerals ( Na, K, Ca & PO4).

d. Regulation of this hormone :

i. ↑ G.H. :

1. GHRF. (growth hormone releasing factor)

2. hypoglycemia.

3. sleep.

ii. ↓ G.H. :

1. GHRIF. (growth hormone release inhibiting factor)

2. hyperglycemia.

3. stress & exercise.

2. Etiology :

a. Adenoma.

b. Hyperplasia.

c. Exogenous intake.
_

3. C / P :

a. C / p of i cause :

i. Adenoma → ↑ ICT.

ii. Homonyms hemianopia.

b. C / p of i hormone :

i. CHO : D.M. in 30% of cases.

ii. Fat : excess lipolysis

→ loss of s.c fat

→ wrinkling of i skin

→ hyperlipidemia.

iii. Protein : excess growth of - bone,

- muscles

- viscera

1. bone

a. face : Ape like

i. enlarged nose, ears, lips & tongue.

ii. bone : big skull,

prominent : - supra-orbital ridges

& - mastoid processes.

iii. prognathism : prominent

lower jaw é separated teeth.

iv. hypertrophy of larynx é hollow deep

voice.

b. hands & feet:

i. spade hands & enlargement of feet.

ii. frequent change in rings & shoes.

iii. Osteoarthritis.

2. visceromegaly :

a. hepatosplenomegaly.

b. cardiomegaly.

3. muscle power :

a. ↑↑ early.

b. ↓↓ late.

iv. Minerals :

_ Na. retention → HTN.

N.B. : HTN is due to :

· Endothelial hyperplasia.

· Na retention.

v. Associated endocrinal manifestation :

1. hyperprolactinaemia in 30% of cases.

2. DM in 30% of cases.

vi. Others :

1. neurological manifestations :

a. depression.

b. peripheral neuritis due to :

i. interstitial neuropathy.

ii. carpal tunnel syndrome.

iii. diabetic neuropathy.

2. pressure manifestations :

4. Investigation :

a. Inv. for i cause :

i. Imaging for i gland :

1. X-ray on skull.

2. C.T. & M.R.I. for skull.

b. Assay of i hormone level :

i. In blood :

1. ↑ G.H. [ normal < 5 n.gm/ml.]

2. ↑ insulin growth factor ( IGF-1) → ↑↑ in

acromegaly.

3. ↑ prolactin in 1/3 of cases.

N.B. :

GH is difficult to measure because of its pulsatile secretions

So , insulin growth factor ( IGF-1 ) produced by liver in

response to GH is measured instead.

c. Inv. of i function of i hormone :

i. Blood :

1. ↑ glucose.

2. ↑ free fatty acids.

3. ↑ Ca. & ↑ P.

ii. X-ray :

1. skull :

a. thickening of cortex.

b. prognathism.

2. hand :

_ mushroom shape.

d. Suppression test :

_ material : glucose I.V.

1. normal → ↓ G.H. level.

2. in acromegaly → no change.

5. Treatment :

a. Surgery : hypophysectomy

  b. Irradiation.

c. Antagonism :

i. Somatostatine analogue [GHRIF] : octereotide.

d. Symptomatic ttt : of

i. D.M.

                                                                             ii. Hypertension