enda-test-pai-acutely-ill-symptoms

name	enda-test-pai-acutely-ill-symptoms
description	Recommends diagnostic testing to exclude primary adrenal insufficiency (PAI) in acutely ill patients presenting with otherwise unexplained volume depletion, hypotension, hyponatremia, hyperkalemia, fever, abdominal pain, hyperpigmentation, or hypoglycemia (especially in children). Use when clinical suspicion arises from these suggestive signs or symptoms suggestive of PAI.

Test for PAI in Acutely Ill Patients with Suggestive Symptoms

STEP 1 — Gather Information

Collect history of acute illness, vital signs (BP, HR, temp), physical exam for volume depletion, hyperpigmentation; order basic labs: serum Na+, K+, glucose, cortisol, ACTH if available.
If any suggestive symptom is present, advance to Step 2; otherwise, consider alternative diagnoses and do not pursue PAI testing.

STEP 2 — Rule In / Rule Out

Assess for presence of unexplained volume depletion, hypotension, hyponatremia, hyperkalemia, fever, abdominal pain, hyperpigmentation, or hypoglycemia (especially in children).
If at least one is present, proceed to Step 3; if none are present, consider other diagnoses and do not test for PAI.

STEP 3 — Classify or Stratify

Determine feasibility of short corticotropin stimulation test (250 µg ACTH).
If feasible, order the test; if not feasible, obtain morning plasma cortisol and ACTH as initial screening.

STEP 4 — Decide

Interpret results: short test peak cortisol <500 nmol/L (18 µg/dL) indicates PAI; morning cortisol <140 nmol/L (5 µg/dL) with ACTH >2× ULN suggests PAI.
If PAI confirmed, initiate stress-dose hydrocortisone and arrange definitive replacement; if not confirmed, exclude PAI and investigate other causes.

Clinical Guardrails / Mimics / Pitfalls

Do not delay empiric stress-dose hydrocortisone in suspected adrenal crisis while awaiting test results; avoid using random cortisol to rule out PAI; be cautious interpreting cortisol in pregnancy, estrogen therapy, or CBG deficiency; do not use dexamethasone for PAI treatment due to lack of mineralocorticoid activity and Cushingoid risk; do not rely solely on symptoms without biochemical confirmation.

Concrete Clinical Example

A 4‑year‑old with fever, vomiting, hypotension, hyponatremia, hyperkalemia, and hypoglycemia. Morning cortisol 80 nmol/L, ACTH 120 pmol/L (elevated). Short ACTH stim test: peak cortisol 300 nmol/L at 60 min (<500). Diagnosis PAI. Patient received IV hydrocortisone 50 mg/m² bolus then continuous infusion, with clinical improvement.

Source: Diagnosis and Treatment of Primary Adrenal Insufficiency: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2016, DOI:10.1210/jc.2015-1710