Endocrine Abstracts

Background: Checkpoint inhibitors like atezolizumab and bevacizumab show promise in treating hepatocellular carcinoma (HCC) but may cause immune-related adverse events (irAEs), impacting various organs. We present a 71-year-old male who developed severe irAEs, leading to Type 1 Diabetes Mellitus (DM) presenting with diabetic ketoacidosis (DKA), and myocarditis.

Case Presentation: A 71-year-old man presented with drowsiness, confusion, agitation, and peripheral edema five days after his first cycle of atezolizumab and bevacizumab. He has past medical history of HCC, liver cirrhosis, tonsillar cancer, deep vein thrombosis, hypertension and hypothyroidism. His medications included bendroflumethiazide, finasteride, thyroxine, tamsulosin, and nystatin. His investigations revealed metabolic acidosis with low bicarbonate, ketonemia, and hyperglycemia consistent with DKA. His other blood tests showed elevated troponin, BNP, C-reactive protein, deranged liver function tests, and acute kidney injury. An electrocardiogram showed a new right bundle branch block. He was initially managed with intravenous antibiotics for sepsis and the DKA was treated as per hospital guidelines, leading to the diagnosis of immunotherapy-induced Type 1 Diabetes Mellitus. He was switched to a basal-bolus insulin regimen once DKA resolved. His echocardiogram showed reduced left ventricular ejection fraction of 41%, along with global hypokinesis and impaired diastolic function. He was reviewed by cardiology team. These changes were attributed to immunotherapy-induced myocarditis and a follow-up was arranged. The oncology team also reviewed his case and started him on Methylprednisolone (1 mg/kg, later 2 mg/kg), which improved his condition.

Conclusion: This case underscores the need for early recognition and rapid, multidisciplinary intervention in managing immune-related adverse events. High-dose corticosteroids remain the cornerstone of treatment for irAEs. Although the patient stabilized, the potential for long-term complications, including the progression of his cardiomyopathy and the management of his new-onset diabetes, will require ongoing monitoring and care.