“Hypopituitarism? ”

Hello. I am deeply struggling with just being connected with everyday life due to persistent fatigue, brain fog causing depression and detachment from social and cognitive performance. I also have allergies and get sick easily with infections, but very hardly I get high body temperature. I am male, 43 years old, 177cm tall, 90kg. I progressively started experiencing this in young age, but now it is getting unbearable. Observing average people just living, I cannot believe they carry my same fatigue burden. I take antidepressants 6 years now. I also experience belly fat gain despite a very healty lifestyle commitment. I have a quite regular thyroid shape (ultrasound) and I extensively tested the thyroid blood values more times, always in ok range. One year ago an MRI found empy sella syndrome. The only 'pituary' hormone tested was ACTH. One year ago was 10.80 pg/ml [< 46]. Two weeks ago I tested it again and it is now <5 pg/ml [< 46]. Endocrinologist dismissed this as they believe it is a lab test mistake. But lab test ensures that the test is valid. Upon my insisting, the endocr. will have me repeat ACTH and cortisol tests only. Note that cortisol is always in ok range, but low in the range. And Vitamin D is always very too. I propose I may have some sort of hypopituarism and would like to test ACTH again but also GH and other related values. Am I right in wanting to suggest to the endocrinologist this idea? If yes, can you suggest which further tests I should ask for? Thank you.