FRI665 Hirata's Syndrome: Autoimmune Hypoglycemia Diagnostic Pathway, A Mexican Case Report

Disclosure: G. Gonzalez De La Cruz: None. D. Porras Farret: None. Introduction: Autoimmune hypoglycemia or Hirata syndrome is a very rare cause of hypoglycemia in western populations, as an example, in Mexico until 2015, there was only a single case reported with these characteristics. Diagnosis is based on episodes of spontaneous, fasting or postprandial hypoglycemia, with endogenous hyperinsulinism, without pancreatic lesions on imaging and positive tests. Objective: To describe the approach to a patient with hypoglycemia, specifically to those with characteristics of autoimmune hypoglycemia syndrome, as well as the general approach to hypoglycemia of endogenous origin and the differential approach in those with a history of type 2 diabetes or drug use with secondary effects. Case description: An 86-year-old woman with a history of high blood pressure, prediabetes, and osteoporosis, presented episodes of dizziness, palpitations, diaphoresis, and syncope, documenting plasma glucose of 40 mg/dl. She was attended by paramedics responding adequately to oral glucose. She was evaluated by Cardiology, Holter was performed with predominant sinus rhythm, frequent atrial extrasystoles (2%) and infrequent ventricular extrasystoles. Next, she was referred to Endocrinology for evaluation and treatment, she was taken empagliflozin as prediabetes medication, and it was suspender. Laboratory studies are requested to address hypoglycemia, with serum insulin levels greater than 600 mU/l, c-peptide 3.9 ng/ml, TSH 6.1, T4T 7.5, T3T 67.8, T4L 1.1, ALT 26 U/L, AST 18 U/L, DHL 247 U/L, GGT 26 U/L, Cortisol 13.8 mcg/dl. An MRI of the upper abdomen was performed where there is no evidence of pancreatic injury. A profile of serum hypoglycemic agents (sulfonylureas in blood) was requested, which were not detected. Subsequently, anti-insulin studies were requested, which were reported in amounts greater than 100 U/ml. The diagnosis of autoimmune hypoglycemia syndrome was made, starting management with prednisone 70 mg every 24 hours, in addition to dietary changes. Conclusion: The approach to hypoglycemia in patients without clear evidence of exogenous administration of hypoglycemic agents must be ordered, taking into account differential diagnoses such as autoimmune causes. In the case of autoimmune hypoglycemia, remission is expected at 6 months, with constant monitoring and adjustment of drugs for underlying pathologies. Presentation: Friday, June 16, 2023