Autoimmune Primary Adrenal Insufficiency in a Pregnant Patient Without Autoimmune Comorbidities.

Background/Objective: Autoimmune primary adrenal insufficiency (APAI), is rare in pregnancy but can be life threatening if left untreated. Diagnosing APAI during pregnancy is challenging, and clinical suspicion may be lower in patients without other autoimmune conditions. This report describes a patient with newly diagnosed APAI in pregnancy in the absence of known pre-existing autoimmune conditions. Case Description: We describe a 29-year-old patient without known autoimmune conditions who presented in the first trimester of pregnancy with severe hyponatremia in the setting of nausea, vomiting, and weight loss. Laboratory evaluation demonstrated a peak cosyntropin stimulated cortisol of 7mcg/dl (normal > 14 nonpregnant, > 25 first trimester), adrenocorticotropin hormone of 1041 pg/mL (normal 7-63) and positive 21-hydroxylase antibodies, confirming the diagnosis of APAI. She was started on hydrocortisone and fludrocortisone and required increasing doses of glucocorticoid over the course of her pregnancy. She ultimately delivered a healthy infant at term. Discussion: New diagnoses of autoimmune endocrinopathies are uncommon in pregnancy, particularly APAI. Most reports of APAI in pregnancy involve patients with pre-existing polyglandular disease, which may raise clinical suspicion for APAI. Patients with APAI often present with symptoms that may also be attributed to normal pregnancy, potentially delaying diagnosis. Conclusion: Clinicians should maintain a low threshold to test for APAI in pregnant patients who present with concerning symptoms, even in the absence of other autoimmune conditions.