Ultrasound Guided Detection and Characterization of Subclinical Lipohypertrophy in Type 1 and Type 2 Diabetes Mellitus

Lipohypertrophy is a well documented phenomenon in patients with diabetes in which hypertrophy and differentiation of adipocytes occurs in the dermal reticular layer at the sites of subcutaneous insulin injection. Currently, lipohypertrophy is assessed by palpating insulin injection sites. The detection on early, non palpable (subclinical) lipohypertrophy remains difficult in the clinical setting. Recent studies have identified distinct ultrasonographic features of hyperechogenicity in areas of adipose tissue consistent with clinical evidence of lipohypertrophy at insulin injection sites, and have detected changes int he thickness of subcutaneous tissue where not clinically evident in population of patients with type 1 diabetes. Lipohypertrophy can adversely affect glycemic control. Injecting into lipohypertrophic areas leads to poor absorption and the need for increasing doses of insulin.

In this study study participants will undergo an assessment for lipohypertrophy during a scheduled visit at the VGH Diabetes Centre. A Diabetes Nurse will assess lipohypertrophy by palpation according to the FIT Protocol. A second diabetes nurse who was not present at the palpation will assess insulin injection sites for lipohypertrophy by ultrasound using a linear probe.