Poster Presentation The Joint Annual Scientific Meetings of the Endocrine Society of Australia and the Society for Reproductive Biology 2017

A case of severe post-prandial hypoglycaemia following gastric bypass surgery (#267)

Dilshani DJ Jayawardene 1 , Rosemary RW Wong 1 , Christopher CG Gilfillan 1
  1. Department of Diabetes and Endocrinology, Eastern health, Melbourne, VIC, Australia

A 38 year-old personal care assistant at a nursing home and mother of three teenage children was referred to our endocrinology unit in October 2015 with a 10-month history of recurrent severe hypoglycaemic episodes.

Past History.                                                      

1993 Vertical banded gastroplasty for obesity, aged 15

2013 Gastrostomy for symptomatic gastric stomal stenosis                                                       

2014 Roux-en-Y gastric bypass surgery for persistent abdominal pain, abdominal fullness, nausea, vomiting and weight loss. Surgery was complicated by pancreatitis requiring prolonged ICU admission.

Presenting Problem. Six months post Roux-en-Y-gastric bypass surgery, this patient’s recurrent hypoglycaemia was first noted. These episodes occurred at all times of the day though were predominantly 2-3 hours post-meals, and resulted in multiple daily unconscious collapses at home and work. It also resulted in a severe unconscious episode whilst driving. On examination, her BMI was 21 and there were no other significant findings.

Investigations and Management. A 72-hour fast was performed. Her plasma glucose fell to 3.8mmol/L at the conclusion of the test with ketones of 4mmol/L. Her C-peptide (0.14pmol/L) and insulin were appropriately low (<1mU/L) excluding the possibility of a fasting hyperinsulinemic state. She was re-admitted for a mixed meal test. Her results reflected a significant insulin surge at 30 minutes post meal ingestion resulting in hypoglycaemia at 120 minutes

A CT Abdomen revealed ‘slight bulkiness’ of the pancreatic head and neck. A GLP-1 Ga-68 PET scan showed diffuse and prominent tracer uptake throughout the pancreas consistent with diffuse islet cell hyperplasia.

Due to the ongoing and prolonged disabling neuroglycopenic effects of hypoglycaemia on her life and intolerance to oral medications for hypo glycaemia, the patient opted for an 80% pancreatectomy in October 2016. Histology confirmed nesidioblastosis. Her most recent HbA1c in February 2017 was 5.3% and a repeat mixed meal test did not reflect a post meal insulin surge or hypoglycaemia.