Brunner’s Gland Hyperplasia in a Patient after Roux-Y Gastric Bypass: An Important Pitfall in GLP-1 Receptor Imaging

Figure 1

(a) Glucose (black circles) and total GLP-1 (red dashed lines) plasma levels (measured by Mercodia AB, Uppsala, Sweden (assay # 10-1278-01) of the patient during a standardized mixed-meal test 300 ml Ensure plus®, Abbott, containing 60 g carbohydrates). The patient developed symptomatic hypoglycaemia at a timepoint of 120 min (2.5 mmol/l) requiring intravenous glucose administration with immediate resolution of symptoms. (b) Representative ⁶⁸Ga-DOTA-Exendin-4 PET/CT image of the patient with a large and strong tracer accumulation (SUVmax 10) in pars 2 duodenii (white arrow). (c) Haematoxylin and eosin staining of a representative duodenal biopsy at 100x resolution showing hyperplastic Brunner’s glands with (d) GLP-1 receptor immunostaining of Brunner’s glands (membranous distribution) and (e) negative immunostaining for insulin each at 200x resolution. All staining was performed with a respective positive control (data not shown).

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