Insulin Injection-Related Skin Lipodystrophies: Blemish or Pathology?

The number of adult individuals with insulin-treated diabetes mellitus (DM) is steadily increasing worldwide. The main local complications of insulin injection are lipohypertrophies (LHs), i.e., subcutaneous nodules consisting of aggregates of macro-adipocytes and fibrin. These nodules result from errors repeatedly made by patients while injecting insulin. Despite being very common, LH lesions/nodules due to incorrect insulin injection techniques are often flat and hardly visible and thus require thorough deep palpation examination and ultrasonography (US) for detection. Identifying LHs is crucial, especially in elderly and frail subjects, because they may eventually result in poor diabetes control due to associated unpredictable insulin release patterns. Raising awareness of the adequate detection of LHs and their clinical consequences is crucial and urgent. A call to action is required on this topic at all levels of undergraduate and postgraduate education.