SUN-073 Autoimmune Polyendocrine Syndrome Type 2 Presenting As New Onset Systolic Heart Failure

Background: Autoimmune Polyendocrine Syndrome Type 2 (APS2) can present with a constellation of autoimmune disorders that evolve over time. Clinical case: A 35 year old woman with a history of Addison’s disease (diagnosed age 4), Hashimoto’s thyroiditis (diagnosed age 21) with longstanding hypothyroidism on levothyroxine, and polycystic kidney disease (PCKD) presented to the emergency department of another hospital with dyspnea and lower extremity edema. Echocardiogram revealed severe mitral regurgitation and left ventricular (LV) ejection fraction (EF) 40%. She was transferred to our hospital for further evaluation. Physical examination was notable for jugular venous distention, hyperpigmentation of palmar creases and buccal mucosa, minimal lower limb edema, and normal thyroid. Initial labs revealed TSH 0.83 (0.34-5.6 µIU/mL), FT4 0.55 (0.8-1.5 ng/dL), TT3 39 (87-178 ng/dL), TPO 28.1 (<5.6 IU/mL), Tg and TSH receptor Abs were negative, TSI 0.71 (<0.55 IU/L). A transesophageal echocardiogram demonstrated a LVEF of 44% with severe LV dilation and diffuse hypokinesis. Coronary angiography did not demonstrate obstructive disease. A cardiac MRI demonstrated global hypokinesis without areas of late gadolinium enhancement. Further history revealed in the 6 months prior to this presentation, she noted 30 lbs (13.6 kg) unintentional weight loss and amenorrhea. Three weeks prior to presentation she was started on lisinopril which caused wheezing and urticaria. She reported a recent adrenal crisis and was found to have a TSH <0.01, TT3 218, FT4 4.0, and elevated TSI. Iodine uptake scan demonstrated diffuse increased uptake, consistent with autoimmune thyrotoxicosis. She was started on methimazole, fludrocortisone, and increased dose of hydrocortisone. Differential diagnosis included hyperthyroid induced adrenal crisis and heart failure, autoimmune cardiomyopathy, or idiopathic nonischemic cardiomyopathy (NICM). Labs revealed negative RF, reticulin Ab, centromere Ab, tissue-transglutaminase, and myocardial Ab non-specific fluorescence. Early AM ACTH 203.5 (7.2-63.3 pg/mL), cortisol 4.0 (6.7-22.6 µg/dL). LH 14.94 (19.2-103 mIU/mL), FSH 6.5 (4.5-22.5 mIU/mL), HgbA1c 4.9%. Hct 30.7 (34-47%), vitamin B12 254 (211-911 pg/mL), homocysteine 17.7 (<11 µmol/L), methylmalonic acid 306 (0-378 nmol/L). Despite initiation of guideline directed medical therapy and volume optimization, an echocardiogram performed 6 weeks later demonstrated a LVEF of 43%. Conclusions: APS2 has typical manifestations of adrenal insufficiency, thyroiditis, and diabetes. This patient had clear evidence for APS2, but also presented with uncommon manifestations, including NICM. She also had wheezing with ACE inhibitor, a symptom of angioedema, not known to be associated with APS2. This case illustrates the importance of diagnosis of APS2 so other manifestations of the syndrome are recognized.