Offer Genetic Counseling for Patients with PAI Due to Monogenic Disorders

STEP 1 — Gather Information

Confirm PAI diagnosis via ACTH stimulation test; collect detailed family history (early-onset PAI, consanguinity, related endocrine disorders), assess for syndromic features (e.g., alacrima, achalasia, neurologic signs, hypopigmentation), review autoimmune antibody panel (21‑hydroxylase, adrenal cortex), and note age of onset and clinical phenotype.

STEP 2 — Rule In / Rule Out

Is there a clinical suspicion of a monogenic cause (early-onset PAI <4 years, syndromic features, consanguinity, positive family history, or autoimmune antibody‑negative PAI)? If yes, proceed to classification; if no, consider autoimmune, infectious, or other acquired etiologies and do not routinely offer genetic counseling.

STEP 3 — Classify or Stratify

Sub‑classify the suspected monogenic disorder based on phenotype: adrenal hypoplasia (NR0B1), familial glucocorticoid deficiency (MC2R, MRAP, etc.), Triple A syndrome (AAAS), adrenoleukodystrophy (ABCD1), or other known genes to guide targeted genetic testing panels.

STEP 4 — Decide

Refer the patient (and family) for formal genetic counseling and discuss the benefits, limitations, and implications of targeted or comprehensive genetic testing based on the classification.

Clinical Guardrails / Mimics / Pitfalls

Do not delay life‑saving glucocorticoid or mineralocorticoid replacement while awaiting counseling; avoid offering counseling in patients with clear autoimmune etiology (positive 21‑hydroxylase antibodies) unless atypical features exist; recognize that negative genetic testing does not exclude all monogenic causes; ensure informed consent regarding psychosocial impact and potential insurance implications.

Concrete Clinical Example

A 2‑year‑old boy presents with PAI (hyperpigmentation, hypoglycemia, low cortisol, high ACTH), negative 21‑hydroxylase antibodies, and a history of a sibling who died in infancy with adrenal insufficiency; parents are second cousins. Suspected monogenic PAI → genetic counseling offered → targeted NR0B1 and MC2R testing arranged.

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