The DERMIS Study: Evaluation of Insulin Pump Infusion Sites in Type 1 Diabetes DERMIS: Evaluation of Pump Infusion Sites
Objective: Continuous subcutaneous insulin infusion (CSII) for type 1 diabetes is increasing in use. Pump site failures are common, yet little is known about the skin changes from pump use. Using noninvasive optical coherence tomography (OCT), OCT angiography (OCTA), and skin biopsies, we evaluated the skin changes of chronic insulin infusion.
Research Design and Methods: In this cross-sectional study an OCT operating at 1310nm central wavelength with a bandwidth of 100 nm was performed immediately before skin punch biopsies were collected at three sites: a “current site”, infusion set removed at time of OCT and biopsy; a “recovery site”, infusion set removed 3 days prior to biopsy: and a “control” site, never used for any insulin infusion or injection.
Results: OCT and OCTA identified characteristics of increased inflammation and vessel density at pump sites compared to control sites. Histological analysis of pump sites showed differences in skin architecture including fibrosis, inflammation including increased tissue eosinophils and fat necrosis. Immunohistochemical staining showed differences between infusion sites and the control sites for staining of insulin-like-growth factor-1 and transforming growth factor β-3.
Conclusions: These findings support allergic sensitization as a potentially common reaction at CSII sites. The leading candidates include insulin preservatives, plastic materials, or adhesive glue used in device manufacturing. The inflammatory response caused by these common allergic responses may result in tissue changes responsible for the infusion site failures seen frequently in clinical practice.