Aldosterone Blood Test - Reasons why a doctor will order it...

I was tested for Aldosterone levels when I had my bloodwork done earlier this week.  I was curious what the test was for so I looked for information about it.  It is a blood test that is ordered sometimes when a patient has high blood pressure.  Especially if the person is young and the cause isn't yet known.  One disorder that the test is used to check for is Primary Hyperaldosteronism (Conn Syndrome).  It is also used to check for Secondary Hyperaldosteronism and Adrenal Insufficiency (Addison's Disease).  If the Aldosterone level is high then you could have a form of Hyperaldosteronism.  If the level of Aldosterone is low, then you can have Adrenal Insufficiency (Addison's Disease).  This article I found tells more in depth about this test and the causes of having high or low levels of Aldosterone....
http://labtestsonline.org/understanding/analytes/aldosterone/tab/test

Here is another article that goes more in depth about what Primary Hyperaldosteronism (Conn Syndrome) is....
http://emedicine.medscape.com/article/117280-overview#showall

This is another article that explains more about Primary and Secondary Hyperaldosteronism....
http://www.nlm.nih.gov/medlineplus/ency/article/000330.htm

This article goes into more depth about what Addison's Disease is....
http://www.mayoclinic.com/health/addisons-disease/DS00361