| name | es-acthd-diagnostic-procedure |
| description | This skill determines the appropriate screening and dynamic testing procedures (e.g., insulin tolerance test, standard or high-dose ACTH stimulation) for diagnosing adrenocorticotropic hormone deficiency in childhood cancer survivors, recommending the same methods used in the noncancer population. Triggers include clinician questions such as “How should I test for ACTHD in this survivor?” or “What dynamic test is appropriate for adrenal insufficiency evaluation?” |
Select ACTHD diagnostic method
STEP 1 — Gather Information
Collect history of hypothalamic–pituitary radiation dose ≥30 Gy, tumor/surgery involving the HP region, presence of other pituitary hormone deficits, and clinical symptoms suggestive of ACTHD (e.g., chronic fatigue, hypotension, hyponatremia, hypoglycemia, weight loss). Also verify prior annual screening results if available.
STEP 2 — Rule In / Rule Out
If the survivor has risk factors and/or symptoms, proceed to dynamic testing; if no risk factors and asymptomatic, routine annual screening suffices and no further testing is needed.
STEP 3 — Classify or Stratify
Choose the insulin tolerance test (ITT) as the preferred dynamic test when safe; if ITT is contraindicated (e.g., seizure disorder, ischemic heart disease), use a standard- or high-dose ACTH stimulation test instead.
STEP 4 — Decide
Perform the selected test and interpret using established cutoffs (ITT: peak cortisol <5 µg/dL indicates ACTHD; ACTH stimulation: peak cortisol <18 µg/dL after 250 µg cosyntropin indicates deficiency). Confirm diagnosis and initiate glucocorticoid replacement education and stress‑dose planning.
Clinical Guardrails / Mimics / Pitfalls
Do not rely on basal cortisol or low‑dose ACTH stimulation to rule out ACTHD; be aware that oral estrogen raises total cortisol‑binding globulin, potentially masking free cortisol deficiency; avoid CRH or glucagon stimulation as primary tests; ITT is contraindicated in uncontrolled epilepsy or significant coronary artery disease.
Concrete Clinical Example
A 16‑year‑old survivor of craniopharyngioma treated with 35 Gy cranial radiation reports fatigue and mild hyponatremia. Annual screening shows a low morning cortisol. An ITT is performed; cortisol fails to rise above 4 µg/dL, confirming ACTHD. The patient receives glucocorticoid replacement instructions and an emergency card.
Source: Hypothalamic Pituitary and Growth Disorders in Survivors of Childhood Cancer: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2018, DOI:10.1210/jc.2018-01175
