| name | es-ghd-provocative-test |
| description | This skill guides selection of an appropriate provocative test for growth hormone deficiency (GHD) diagnosis in childhood cancer survivors when clinicians ask, "What test should I use to diagnose GHD in this survivor?" or "Which provocative test is appropriate for GHD evaluation?" It recommends using the same testing modalities as in the noncancer population, tailored to patient-specific contraindications. |
Select provocative test for GHD diagnosis
STEP 1 — Gather Information
Collect history of cranial/spinal radiation dose, presence of seizure disorder or significant cardiac disease, symptoms of GHD (growth deceleration, low IGF-I, increased fat mass), baseline IGF-I level, and number of other confirmed anterior pituitary hormone deficits.
STEP 2 — Rule In / Rule Out
If the patient has three or more other confirmed anterior pituitary hormone deficits, skip provocative testing for GHD (per 2.6); otherwise proceed to evaluate test options.
STEP 3 — Classify or Stratify
Classify test suitability: avoid insulin tolerance test (ITT) in seizure disorder or coronary artery disease; avoid glucagon test in insulinoma; avoid GHRH alone if hypothalamic-pituitary radiation damage is suspected; otherwise prefer ITT (most reliable) or glucagon/arginine as alternatives.
STEP 4 — Decide
Order the selected provocative test using established GH cut-offs (e.g., ITT peak GH <5 µg/L, glucagon <3 µg/L, arginine <0.4 µg/L) to confirm or exclude GHD.
Clinical Guardrails / Mimics / Pitfalls
Do not use ITT in patients with uncontrolled seizure disorder or significant cardiac disease; do not use glucagon in insulinoma; do not rely on GHRH alone after hypothalamic radiation; do not use spontaneous GH secretion as a diagnostic test; do not rely solely on IGF-I levels for diagnosis.
Concrete Clinical Example
A 16-year-old medulloblastoma survivor who received 24 Gy craniospinal radiation presents with slowed growth velocity and low IGF-I. No seizures or cardiac disease. Three other hormone deficits are absent. ITT is selected as the preferred test due to its reliability and absence of contraindications.
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
