Cushing's Syndrome.

-Cushing syndrome is a disorder that occurs when your body is exposed to high levels of the hormone cortisol. It may also occur if you take too much cortisol or other steroid hormones.
or
-chronic increased in free circulating level of glucocorticoids.

Causes:
ACTH dependent(80%)
-cushing's disease, ectopic ACTH syndrome(CA pulmonary, prostate,  ???
-ACTH administration
-
-
Non ACTH dependent
-adrenal gland adenoma, CA adrenal, glucocorticoids administration,alcohol
(pseudo-cushing disease)

Clinical signs and symptoms:

-ACTH independent:
                          -excessive cortisol--->increased in appetite--->deposition of fat in face-->full moon face, also, buffalo hump, truncal obesity
                          -increased boold level<----hepatic gluconeogenesis--->glucose intolerance
                          -increased susceptibility to infection, esp fungal<----decreased immunity

-ACTH dependent:--->all gluc, meniralco,,corticosteroids increased.
                        -hyperpigmentation
                        -hirsutism, acne, amenorrhoea, musculine voices, sodium and water retention<----hyperaldosteronism.
                         -weight gain and blodd pressure
                         -hypokaelemia alkalosis
                         
others:
-polyuria, muscle ache, 

Diagnosis:
after presenting with those cushingoid features , we do confirmatory Ix.,
-Investigation-
48 hour low dose dexamethasone Test.--high sensitivity--97%
0.5 mg 6 hourly(8 dose)
in normal, cortisol level- supression present-->  =<50nmol/L
-24 hr urinary cortisol level test.
-Circaian rhythm: pulsatility release, morning highest level(9pm-180-700nmol/L)---->measured at night when low.(<100nmol/L)...opposite to GH

In Cushing, midnight level will be >100nmol/L though 24 hour level may be normal.

-insulin stress test.
-desmopressin stimulation test.
CRH test.

Differential diagnosis:
-bichemical and radiological test:
-adrenal CT/MRI scan.
-plasma K+ level--if hypokalemia
-Plasma ACTH level.
-CRH test.

Treatment:...???..read!
iatrogenic- no treatment
transsphenoidal hypophysectomy
bilateral adrenalectomy.