Tom,

 

Like you, I also think they should be able to tell if it’s a type of HA or a type of PHA, by measuring the levels of aldosterone. Didn’t you say in one of your earlier posts---when they still thought it was CAH---that you thought it was odd that they were giving your son sodium, but not florinef? That one of the doctors had told you the results of your son’s urine test showed he didn’t need it? (florinef)?  Maybe you hit the nail on the head with that thought.  Perhaps his urine showed normal levels of aldosterone, which would then favor the PHA theory.  Maybe it’s something to ask the doctors about again. However, I know you also said the doctors recently started your son on florinef, after all.  Did they give you an explanation why the sudden about-face?   

 

The two types of HA that you mentioned, caused by defects of the CYP11B2 gene, are also commonly referred to as AME (Apparent Mineralocorticoid Excess) or Aldosterone Synthase Deficiency.  You’ll be able to find a considerable amount written in the medical literature, if you also search using those two names.  AME is also EXTREMELY rare....I think only 40+ diagnosed cases, since the 1990’s.  Any way you look at it, it appears you may have "won" the lottery. 

 

Aside from the aldosterone issue, however, there are other distinguishing features between AME and types of PHA, so it seems to me that they should also be able to figure out which one it is, by looking at some of the other results from the bloodtests.  For example:

 

AME would result in:  low aldosterone, low sodium, high blood pressure, low potassium

PHA would result in:  normal/high aldosterone, low sodium, low blood pressure, high potassium

 

Your son’s potassium was on the high side, wasn’t it?  If his aldosterone levels were also normal, it seems like it would stack things up in the PHA column even further.  I think those with AME also often have high calcium levels. 

 

I do believe that "autosomal dominant" would mean that either you or your wife would have to have the condition.  "Autosomal" means that it is not sex-linked, meaning that both sexes would have equal chance of inheriting the condition (unlike something like hemophilia, for example, which is also dominant, but is sex-linked so only males get it.)  "Dominant" means that only one parent has to carry genes for the condition. 

 

I’m not sure what the likelihood is that either you or your wife could be walking around with PHA type 1, yet not know it.  On the other hand, it seems possible to "outgrow" PHA type 1, or be asymptomatic, so I suppose it’s possible.  If that is the case, it might mean that your son could also eventually outgrow his condition.

 

One other small consolation, if your son IS found to have some form of PHA: the doctor of the emedicine article is at the Texas Health Sciences Center.  Isn’t that in your neck-of-the woods?  One of the things I like about emedicine.com is that articles generally

appear to be written by those who have significant reputations in their fields.  So, if your son IS found to have some form of PHA, perhaps one of the "experts" in the field is actually at your back door???

 

Lastly, it seems to me that HA and PHA are just "umbrella categories" used to describe a variety of different conditions.  For example, both CAH and Addison’s disease would also be examples of "hypoaldosteronism." It also seems to me that conditions to do with hypoaldosteronism are more "endocrine" problems, while conditions to do with pseudo-hypoaldosteronism are more "nephrology" problems, i.e. to do with the kidney.  As a result, it seems to me that---if some form of PHA is a real possibility here---consultation with a pediatric nephrologist is as important as, if not more important than, consultation with a pediatric endocrinologist. Maybe it’s also worth trying to talk to one?