Early detection of cutaneous complications of insulin therapy in type 1 and type 2 diabetes mellitus

Abstract

Background: Subcutaneous insulin therapy is associated with important injection site complications, which can influence insulin pharmacokinetics resulting in glycemic fluctuations above and below target levels for blood glucose. Objective: Our objective was to assess the prevalence and risk factors of cutaneous complications including insulin derived amyloidosis in insulin-injecting diabetes patients and to study the role of ultrasonography (in comparison to gel-assisted palpation) in early diagnosis of lipohypertrophy (LH). Methods: This was a cross-sectional study conducted at a tertiary care center in India, wherein 500 patients injecting insulin for ≥2 years were randomly enrolled and evaluated for the presence of cutaneous complications of insulin therapy through clinical examination, ultrasonography and punch biopsy of skin. Results: Clinical examination detected LH in 44.6% of patients. Ultrasonography diagnosed additional 13.4% of patients with LH which were missed on clinical examination. Incorrect rotation of sites (P < 0.001) and insulin syringe reusage for more than five times (P < 0.001) significantly increased the risk of LH. Skin biopsy was performed in 100 cases, out of which two patients showed apple green birefringence and its association with insulin was confirmed by positive staining with anti insulin antibody in these two patients. Conclusion: Improper rotation of sites and reuse of needles were the leading causes of LH in Indian diabetic patients. Ultrasonography is more objective and reliable method of detecting LH. Insulin-derived amyloidosis may be a more common complication of insulin therapy than previously thought. © 2021 Primary Care Diabetes Europe