Too Low From a Self-Blow: Diagnostic and Therapeutic Challenges in a Case of Hirata’s Syndrome
https://doi.org/10.15605/jafes.041.S1
- Author:
Tharsini Sarvanandan
1
;
Ying Guat Ooi
1
;
Jun Kit Khoo
1
;
Tricia Lopez
1
;
Nicholas Ken Yoong Hee
1
;
Shireene Vethakkan
1
;
Lee-Ling Lim
1
;
Jeyakantha Ratnasingam
1
;
Carolyn Chee
1
;
Pavai Sthaneshwar
2
;
Quan Hziung Lim
1
Author Information
1. Endocrine Unit, Department of Medicine, Faculty of Medicine, University Malaya
2. Department of Pathology, Faculty of Medicine, University Malaya
- Publication Type:Journal Article
- From:
Journal of the ASEAN Federation of Endocrine Societies
2026;41(S1):50-
- CountryPhilippines
- Language:English
-
Abstract:
Introduction:Non-diabetic hypoglycemia in older adults warrants
careful evaluation across insulin-mediated and noninsulin-mediated causes. We present a challenging case of
insulin autoimmune syndrome (IAS; Hirata’s syndrome).
Case:An 85-year-old female presented with severe hypoglycemia (capillary blood glucose [CBG] 1.8 mmol/L) with
reduced consciousness, preceded by 2 months of recurrent
dizziness relieved by food intake. Appetite and weight were
stable. Past medical history included stage 3 chronic kidney
disease and osteoporosis, but no diabetes. Medication
review revealed a recent 2-week course of traditional
supplement, long-term Neurobion®, but no agents with
recognized hypoglycemic potential. Physical examination
showed a moderately built elderly female with a body
mass index of 24.3 kg/m² and no Cushingoid features.
Recurrent hypoglycemia (CBG nadir 1.5 mmol/L) occurred
in both fasting and postprandial states, fulfilling Whipple’s
triad. Baseline investigations showed an estimated
glomerular filtration rate of 42 mL/min/1.73 m², AM
cortisol of 700 mmol/L, and unremarkable liver and thyroid
function tests. During a hypoglycemic episode (CBG 2.3
mmol/L), plasma insulin and C-peptide were inappropriately raised at 203.6 mU/L (reference interval [RI]: 3.0–
25.0) and 33 ng/mL (RI: 0.9–7.1), respectively, confirming
endogenous hyperinsulinemic hypoglycemia. Polyethylene
glycol precipitation showed 21% insulin recovery, raising
suspicion for an autoimmune cause. Elevated insulin
autoantibodies (175 AU/mL; RI <20) confirmed IAS.
Computed tomography of the abdomen and endoscopic
ultrasound excluded a pancreatic neuro-endocrine tumor.
Nutritional management comprising frequent low glycemic
index feeds and uncooked cornstarch was commenced.
Diazoxide 100 mg TDS caused fluid overload and severe
hyponatremia, while hypoglycemia persisted at lower doses, necessitating discontinuation. Subcutaneous octreotide 100 mg QID was required to control hypoglycemia.
Prednisolone 30 mg BD improved glycemic stability. Insulin
autoantibodies titer remained 175 AU/mL at 2 weeks;
reassessment was conducted at 4 weeks with consideration for biologics if persistent.
doses, necessitating discontinuation. Subcutaneous octreotide 100 mg QID was required to control hypoglycemia.
Prednisolone 30 mg BD improved glycemic stability. Insulin
autoantibodies titer remained 175 AU/mL at 2 weeks;
reassessment was conducted at 4 weeks with consideration for biologics if persistent.
Conclusion:Endogenous hyperinsulinemic hypoglycemia, after
excluding insulinoma, should raise suspicion for IAS.
Management includes removing triggers, supportive care,
and immunomodulatory therapy in severe cases.
- Full text:2026073013504362849EP_A056.pdf
