PET Imaging to Delineate Macrophage Activation in Diabetic Gastroparesis

Dynamic Positron Emission Tomography Imaging With 11C-ER176 to Delineate Macrophage Activation in Diabetic Gastroparesis

Macrophage-driven immune dysregulation has been shown to be involved in pathophysiology of diabetic gastroparesis. Currently, there are no non-invasive ways to study macrophage activation in humans. The researchers are trying to determine the utility of 11C-ER176 based PET-CT scanning to determine pro-inflammatory macrophage activation in gastric wall of patients with diabetic gastroparesis.

Inclusion Criteria:

• Age: 18 to 70 years of age.
• Ability to provide informed consent.
• Type I or II diabetes mellitus.
• Gastroparesis defined by gastric retention of Tc-99m > 60 % at 2 hrs and/or > 10% at 4 hours on scintigraphy.
• Average Gastroparesis Cardinal Symptom Index (GCSI) ≥ 3 indicating moderate-severe symptoms.

Exclusion Criteria:

• Women who are pregnant or cannot stop breast feeding for 24 hours.
• Using anti-coagulants, anti-inflammatory medications (NSAIDs, corticosteroids, etc.) or immunosuppressive therapies within the 4 weeks prior.
• Opioid use within the last 4 weeks of gastric emptying scintigraphy.
• Prior gastric surgery.
• History of IBD, celiac disease, eosinophilic gastroenteritis, microscopic colitis.

Healthy Subjects Exclusion criteria

• no clinical history of diabetes or any GI symptoms
• no inflammatory disorders of the GI tract
• no use of anti-inflammatory or immunosuppressive therapies