Watching with interest, as my husband and son (12) both have low cortisol/adrenal insufficiency. Frustratingly and worryingly, the care/treatment they are both receiving are poles apart.
Son's cortisol results for AM have been as low as ~80, but typically ~120 and he is struggling with school, depressed, exhausted, always run down...yet the endo consultant is of the 'watch and wait' attitiude, and the cons secretary is useless; forgets to send out blood forms, months of inaction, missed details in letters??
Same with his abnormal thyroid, autoimmune markers and low iron stores (which I spotted on lab report - cons missed it?) and abnormal MRI showing a 'partially empty sella' - a slightly squished pituitary gland. She doesn't think it is connected. I promise I am not making this up, I wish I was.
I have had to instruct the cons else nothing happens, push for specific blood tests, short synacthen test, MRI...the original response was to just monitor him and refer to a sleep clinic! Managed to organise a short synacthen test, which showed a normal response, so this cemented the theory that this issue was from the pituitary gland. This has dragged on for 2 years, and still we are fighting t get him treated. We now have a second opinion organised via the same team.
He is also high functioning autistic so life at school has been a battle as it is, and now this. We are on the cusp of complaining, yet again, as he has just been left, forgotten; his symptoms arose in 2019 yet we had to wait almost 2 years to be seen and still, here we are with zero treatment, sending endless emails, calls and a fear that he could collapse with an adrenal crisis. He also has a dangerous heart condition. GP hands tied. We feel as though nothing will change from their POV until he collapses/dies.
Husband - also chronically fatigue and was being told it was stress/lack of sleep etc...I suggested a cortisol screening via GP and these readings showed similar results to our son! Referall to a very proactive consultant who has carried out the short synacthen test (normal) but opted to treat the low cortisol, ordered an emergency steroid injection kit and treat the wonky thyroid. All within a year.
I looked into a private referall for our son despite being very low income, as was so terrified at the lack of care via the NHS yet seeing how my husband has been cared for, I now see that there is a serious failing by this particular endo. All I can say is, don't be fobbed off, do your research via trusted sources (NICE guidelines, endocrinologist organisations, charities that support those with adrenal insufficiency even if you don't have this, as it gives an idea of the pathways taken when there is a clinical suspicion).
Good luck with the investigations. I am not medically qualified. All I would say if I was in your situation is do your research via professional resources and go armed and prepared when you see the doctor/specialist; look into the day long cortisol screening, I believe this is the saliva test or even read up on the short synacthen test plus possible autoimmune screenings, and don't forget the thyroid function.