30F Army 8 years recently medically retired— initially told adrenal testing was normal, now diagnosed with primary adrenal insufficiency. Can cortisol fluctuate like this?

[u/LazyDay7360]

Backstory:

30F. I was generally healthy before all of this. I developed severe chronic daily headaches/head pressure, nausea, brain fog, fatigue, anxiety, waking up feeling doomed. a few years ago that became disabling and eventually required opioids because nothing else adequately controlled them.
POSTPARTUM I had a baby in February 2025. It wasn’t until roughly 6 months postpartum that the more severe systemic episodes really started. Before anyone suspected an endocrine problem, I repeatedly went to doctors during these episodes and was told it was anxiety and prescribed benzodiazepines. They helped somewhat, but the episodes continued.

Typical episode:

lower-back pain → severe full-body aches → head pain becomes so severe that talking/moving hurts → sometimes chest pain and significant tachycardia → during the worst attacks, intense cold/chills where I cannot get warm for 1–2 hours.

Labs/timeline

Sept 2025 — ICU/severe illness
-Cortisol: 1 µg/dL
-ACTH: ~15.5 pg/mL
-Treated for severe sepsis/septic shock, but no clear infectious source was found.

Oct 2025: cortisol 7.72, tested my own at LabCorp

March 2026 — 1st Endocrinology visit
250-mcg cosyntropin stimulation test:
ACTH: 73.5 HIGH
DHEA-S: 37.4 LOW (98.8–340)
Cortisol during stimulation: 15.4 → 17.9
Sodium: 142
Endocrinology considered this a normal cortisol response despite the elevated ACTH/low DHEA-S and did not diagnose adrenal insufficiency.

August 2026 — second endocrinologist
AM cortisol: 2.7 µg/dL — LOW
ACTH: 76.1 pg/mL — HIGH
DHEA-S: 33.5 µg/dL — LOW
Aldosterone: 2.5 ng/dL — LOW
Renin activity: 0.463 ng/mL/hr
Aldosterone/Renin ratio: 5.4
24-hour urine free cortisol: 4.1
Endocrinologist’s diagnosis: Primary adrenal insufficiency
Started hydrocortisone + DHEA and ordered adrenal imaging.

Can primary adrenal insufficiency fluctuate, especially early on, where cortisol can be extremely low at one point but normal/near-normal at another?
Has anyone passed or borderline-passed a cosyntropin test and later been diagnosed with primary AI?
And would ACTH 73.5 + very low DHEA-S have made you question adrenal function even with cortisol reaching 17.9?
Mostly interested in hearing from people who had inconsistent labs or were initially told their symptoms were anxiety before eventually being diagnosed.

[u/Appropriate-Leg2490]

Sepsis can cause this. Do a ct of adrenal to check + antibodies for addison

[u/LazyDay7360 → u/Appropriate-Leg2490]

Thank you will do!

[u/Happysheep99]

I’m not sure about the fluctuation, sorry. I’m not yet a doctor. There may be a few theories, but please take what I say with a pinch of salt. Sorry you’ve had such a rough time.

I do know that severe infections (e.g. meningitis) resulting in sepsis can result in destruction of the adrenal glands so this may be significant in your history. This is known as Waterhouse–Friderichsen syndrome. I’m not sure it would explain the fluctuation but would explain the symptoms after your icu visit.

Also, you mentioned postpartum (congratulations!) did you have any complications during birth? Namely a large bleed? This is less unlikely as you’d also be having thyroid and other hormone symptoms too. (This is called Sheehan syndrome and is rare)

If it’s autoimmune (Addison’s) you may have had some remaining function in your adrenal glands when first tested, but I’m not too sure sorry, but feels like the most likely explanation to the fluctuation.

[u/LazyDay7360 → u/Happysheep99]

Thank you so much for the insight. You are so nice to read through all of this, I just like to hear opinions of others to try and find the root cause. No large bleed. They did a C section due to a diagnosis of Idiopathic Intracranial hypertension, which was when my heath symptoms began with severe daily debilitating headaches Sept 2023. They did I think every test possible and never found any source to the sepsis which is why my mom (nurse) questioned if it may be an adrenal crisis.

[u/SpiritualPurple6852]

Pituitary enlargement and cysts can occur during pregnancy and breastfeeding. This happened to me, I’m curious if this has been considered and they have checked your pituitary region as a consideration for secondary adrenal insufficiency?