Functional imaging in hyperinsulinemic hypoglycemia after gastric bypass surgery for morbid obesity.

Abstract

CONTEXT:

Hyperinsulinemic hypoglycemia after Roux-en-Y gastric bypass (RYGB) has been increasingly reported. It is induced by β-cell hyperplasia often referred to as nesidioblastosis. Positron emission tomography (PET) with [11C]-5-hydroxytryptophan ((11)C-HTP) and 6-[18F]fluoro-3,4-dihydroxy-l-phenylalanine ((18)F-DOPA) has been successfully applied to image neuroendocrine tumors. No data are available of the usefulness of these functional imaging techniques in post-RYGB in this new endocrine disorder, neither for diagnostic purposes nor for follow-up.

OBJECTIVE:

We present a patient with post-RYGB hypoglycemia who underwent (11)C-HTP and (18)F-DOPA PET scintigraphy for diagnostic purposes and to evaluate the effect of additional laparoscopic adjustable banding of the pouch as a surgical therapy for this disorder.

PATIENT:

We describe a woman with biochemically confirmed post-RYGB hypoglycemia who showed diffuse uptake of the (11)C-HTP and (18)F-DOPA tracers in the entire pancreas. After failure of dietary and medical treatment options, she underwent a laparoscopic adjustable banding for pouch dilatation. Subjective improvement was noted, which coincided with decreased uptake of (18)F-DOPA and (11)C-HTP in the head of the pancreas.

CONCLUSIONS:

Functional imaging by (18)F-DOPA- and (11)C-HTP-PET can accurately visualize diffuse endocrine pancreatic activity in post-gastric bypass hyperinsulinemic hypoglycemia. Both (11)C-HTP- and (18)F-DOPA-PET imaging appear to have a similar diagnostic performance in the presented case, and uptake of both tracers potentially relates to disease activity after surgical intervention.

• Authors: Loek J M de Heide, Andor W J M Glaudemans, Peter H N Oomen, Jan A Apers, Eric R E Totté, André P van Beek
• Journal: The Journal of clinical endocrinology and metabolism (J Clin Endocrinol Metab) Vol. 97 Issue 6 Pg. E963-7 (Jun 2012) ISSN: 1945-7197 [Electronic] United States
• PMID: 22466332 (Publication Type: Case Reports, Journal Article)

Chemical References

• Carbon Radioisotopes
• Fluorodeoxyglucose F18
• fluorodopa F 18
• Dihydroxyphenylalanine

Topics

• Adult
• Carbon Radioisotopes
• Dihydroxyphenylalanine (analogs & derivatives)
• Female
• Fluorodeoxyglucose F18
• Gastric Bypass (adverse effects)
• Humans
• Hyperinsulinism (diagnostic imaging, etiology)
• Hypoglycemia (diagnostic imaging, etiology)
• Nesidioblastosis (diagnostic imaging, etiology)
• Obesity, Morbid (surgery)
• Positron-Emission Tomography (methods)
• Postoperative Complications (diagnostic imaging)