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+--- Thread: Addison vs. adenoma of pituitary - somber (/showthread.php?tid=72202)
Addison vs. adenoma of pituitary - somber - ArchivalUser - 01-29-2006
do they both present with cushing? since ACTH is high, and cortisol low? also do they both cause hyperpigmentation? how can you really distinghuish one from the other?
thanks in advance
0 - ArchivalUser - 01-29-2006
what i think is with Addison problem is in adrenal cortex ( thus low cortisol) , low cortisol causes positive feedback to increase pituitary secretion of ACTH. In pit adenoma problem is at pituitary ( excess pdtion of ACTH) which causes causes increased cortisol. Cushing occurs in hypercortisolism thus in pit adenoma, but not in addison.
In addison there is hyperpigmentation ( aka Nelson syndrome) because the excess ACTH pdtion which has similar sequence to melanocyte stimulating hormone.
Not sure if same occurs in pit adenoma
0 - ArchivalUser - 01-29-2006
thank you, yes I can see that better now =)