Endocrine Abstracts

Background: The exact changes of hormones and the relative importance of these to the metabolic improvement after bariatric surgery remain to be explored. We highlight the unusual case of a patient who developed episodes of angioedema post roux-en-y surgery for weight reduction.

Case: A 38-year-old man with a BMI of 50 kg/m², had laparoscopic Roux-en-y bypass surgery, resulting in 89 kg loss over 12–18 months. Six to twelve 12 months post-op he developed recurrent facial angioedema and mild urticaria, lasting for 6–12 h, relieved with oral steroids and antihistamines. Two of these episodes were associated after taking ibuprofen. A low salicylate diet was ineffective as were multiple antihistamines at up to triple standard doses at preventing the reactions.

Tests for autoimmunity, food allergy, C1 inhibitor deficiency, mast cell tryptase, pheochromocytoma, and carcinoid including octreotide scintigraphy were negative. His plasma gut peptide profile was within the normal range. As several urinary 5-HIAA levels were borderline elevated (52.8, 54.1 and 36.5 μmol/day, normal 0–50) he was commenced on octreotide and has since remained symptom free. Attempts to reduce the octretide dose result in return of symptoms, indicating that he does not just have chronic urticaria that has now resolved.

Discussion: There is progressive rise in peptideYY, enteroglucagon, pancreatic polypeptide and GLP-1 after gastric bypass surgery. Somatostatin and its analogue octreotide inhibit the release of peptide hormones through stimulation of somatostain receptors and inhibition of L-type calcium channels. Octreotide induced modulation of post bypass satiety gut hormone release is proven in animal models. We hypothesise the response seen in this case is due to modulation of certain gut peptide(s) with angioneurotic properties.

Conclusion: Trials of octreotide therapy may be useful in similar patients.