Screen Annually for Autoimmune Diseases More Prevalent in PAI Patients
STEP 1 — Gather Information
Confirm diagnosis of primary adrenal insufficiency (PAI) and assess whether autoimmune origin has been excluded (e.g., 21-hydroxylase antibody testing). Collect patient age, sex, and any known autoimmune comorbidities. If autoimmune serology status is unknown, order 21-hydroxylase antibody test.
STEP 2 — Rule In / Rule Out
Is autoimmune origin of PAI excluded by negative 21-hydroxylase antibodies?
- Yes: Stop; annual autoimmune screening per this guideline not indicated.
- No or unknown: Proceed to step 3.
STEP 3 — Classify or Stratify
Classify patient as requiring annual screening for autoimmune conditions more prevalent in PAI with uncertain autoimmune origin: thyroid disease, type 1 diabetes mellitus, premature ovarian failure, celiac disease, and autoimmune gastritis with vitamin B12 deficiency.
STEP 4 — Decide
Order annual screening labs: TSH and free T4 for thyroid disease; HbA1c for diabetes; serum vitamin B12 and anti-parietal cell antibody (if B12 low) for autoimmune gastritis; anti-tissue transglutaminase IgA with total IgA for celiac disease; and consider FSH/LH or AMH for premature ovarian failure in appropriate patients.
Clinical Guardrails / Mimics / Pitfalls
Do not screen if autoimmune origin definitively excluded; do not rely on symptoms alone to trigger screening; avoid unnecessary repeat testing within 12 months unless clinically indicated; remember that pregnancy may alter interpretation of thyroid and glucose tests; consider HLA-DQ2/DQ8 genotyping if serology equivocal for celiac.
Concrete Clinical Example
A 34‑year‑old woman with PAI of uncertain autoimmune origin (21‑hydroxylase antibody not sent) presents for routine follow‑up. She has no autoimmune symptoms. Step 1 confirms PAI and unknown serology. Step 2 finds autoimmune origin not excluded. Step 3 classifies her for annual screening. Step 4 orders TSH, free T4, HbA1c, vitamin B12, anti‑tTG IgA, and anti‑parietal cell antibody; all return negative, and screening is repeated annually.
Source: Diagnosis and Treatment of Primary Adrenal Insufficiency: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2016, 10.1210/jc.2015-1710