PSAT042 Adrenal Insufficiency Associated to Immune Checkpoint Inhibitors

BACKGROUND: Innovations in management of multiple malignancies have developed throughout the years. Despite benefits in immune checkpoint inhibitors there is an incidence of approximately 9.4% to 10.4% in endocrine immune related disorders. The challenge advocates to promptly recognize the clinical manifestations related to adverse effects. CLINICAL CASE: We report a case of a 61-year-old caucasian woman with Metastatic Lung Squamous Cell Carcinoma Stage IV on immunotherapy and radiotherapy who presented to ED with nausea and vomiting for the last 2 weeks. The review of the system pertinent for weight loss 18 pounds in the last 2 months, fatigue and decreased appetite. Medication history pertinent for active Pembrolizumab (started 6 months prior to presentation; cycle every 3 weeks); Radiotherapy (3 cycles) and steroid injections (last dose 1 month prior for bilateral knee pain). Upon arrival vital signs T 36.9C, HR 110/min, RR 18/min, BP 80/60mmHg, and StO2 98%. The physical examination pertinent for an acutely ill patient with tachycardia. Initial laboratory studies showed peripheral eosinophilia 14% (n <6%); high anion gap metabolic acidosis (AG 18), hypokalemia 2.8 mmol/L (n 3.5-5.0mmol/L). The patient was hospitalized with sepsis and intractable vomiting. Gastroenterology evaluated with EGD showed erosive gastritis and reflux esophagitis. CT abdomen with IV contrast showed numerous sclerotic bone lesions and single hepatic lesion suggestive of metastatic disease; unremarkable adrenal glands. Poor response to initial hydration and antibiotics as blood pressure remained fluctuant borderline low prompted evaluation. Random cortisol at 6: 50am showed hypocortisolism (1.6mcg/dl) and TSH 1.290 mcIU/mL (n 0.358- 3.74mcIU/mL); patient was started on stress dose steroids and endocrinology was consulted for suspected adrenal insufficiency. Cosyntropin stimulation test (n >18 mcg/dL) with baseline cortisol levels 1.6mcg/dl and ACTH less than 5mcg/dl; cortisol levels at 30 minutes after 250 mcg of Cosyntropin was 4.3mcg/dl and at 1 hour 6.8mcg/dl, confirming most likely secondary vs primary adrenal insufficiency. Within 24-48 hour stress dose steroids were weaned and the patient was then discharged home with hydrocortisone 20 mg am and 10mg pm for further outpatient management. CONCLUSION: Pembrolizumab is a human programmed death receptor-1-blocking antibody that on October 2015 was FDA approved for treatment of non-small cell lung cancer. Adrenal Insufficiency can cause a broad nonspecific clinical scenario with reported incidence of 0.6-0.7% pembrolizumab-induced AI. This rare clinical entity adrenal insufficiency immune mediated endocrinopathy by pembrolizumab constitutes an emergency that prompts attention for early identification and initial management. Nevertheless increased morbidity and mortality is associated with acute adrenal crisis encouraging physicians to be aware of this particular risk. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.