| name | endo-hirsutism-screen-nccah-amenorrhea |
| description | Orders early morning 17‑hydroxyprogesterone to screen for nonclassic congenital adrenal hyperplasia due to 21‑hydroxylase deficiency in hyperandrogenemic women with amenorrhea or infrequent menses. Triggered by menstrual irregularity with hirsutism and a clinical request to rule out adrenal hyperplasia. |
Screen for NCCAH in amenorrheic or infrequent menses women
STEP 1 — Gather Information
Collect menstrual history (amenorrhea or <6 cycles/year), hirsutism assessment (Ferriman‑Gallwey score ≥8), signs of hyperandrogenism, family history of congenital adrenal hyperplasia, and ethnicity; order early morning (08:00–10:00) 17‑hydroxyprogesterone (17‑OHP) level.
STEP 2 — Rule In / Rule Out
Is the early morning 17‑OHP ≥ .170 ng/dL (5.15 nmol/L)?
- Yes → proceed to Step 3 (possible NCCAH).
- No → rule out NCCAH; consider other causes of hyperandrogenism.
STEP 3 — Classify or Stratify
Classify 17‑OHP:
- .170–200 ng/dL (5.15–6.0 nmol/L): borderline positive (≈95% sensitive, 90% specific).
- ≥1000 ng/dL (30–45 nmol/L): diagnostic for NCCAH.
- < .170 ng/dL: negative.
STEP 4 — Decide
If 17‑OHP ≥1000 ng/dL: refer for CYP21A2 genetic testing and consider low‑dose glucocorticoid therapy.
If 17‑OHP .170–200 ng/dL: perform ACTH stimulation test; if peak 17‑OHP ≥1000 ng/dL, proceed to genetic testing.
If 17‑OHP < .170 ng/dL: reassess for PCOS or idiopathic hirsutism; no further NCCAH work‑up.
Clinical Guardrails / Mimics / Pitfalls
Do not rely on random‑time 17‑OHP or DHEAS as primary screen; avoid testing in eumenorrheic women without hirsutism; false positives may occur with acute illness or stress; false negatives if sample not drawn in early morning; do not initiate glucocorticoids without confirmed diagnosis.
Concrete Clinical Example
A 28‑year‑old woman reports 6 months of amenorrhea, mild hirsutism (FG score 12), and requests evaluation for adrenal hyperplasia. Early morning 17‑OHP is 180 ng/dL (borderline). She has no family history. An ACTH stimulation test yields a peak 17‑OHP of 1200 ng/dL; genetic testing confirms a pathogenic CYP21A2 variant, establishing NCCAH diagnosis.
Source: Evaluation and Treatment of Hirsutism in Premenopausal Women: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2018, DOI: 10.1210/jc.2018-00241
TODO: consider adding scripts/calc.py for the endo-hirsutism-screen-nccah-amenorrhea calculator