Insulin allergy in a diabetic patient: Potential factor to increase malignancy incidence

Diabetes mellitus is a universal disease, and insulin is essential to control patients´ blood glucose level. In some clinical cases, the diabetic patients suffer from insulin allergy, and even some of them fall into allergic shock and death. In order to analyze the potential influence of insulin allergy on systematic organs, here we report a 64-year-old patient with type 2 diabetes mellitus and administrated by insulin injection. After 3 to 4 months of insulin therapy, rashes and itching presented on the patient´s generalized skin; renal carcinoma was discovered after 1 year. The results showed that the patient appeared allergy to insulin and phenol and meta-cresol inside the insulin injection may be sensibiligen. In conclusion, phenol and meta-cresol are accumulated during long-term use of insulin in patients with diabetes and may initiate occurrence of carcinoma. Clinical investigation about carcinogenicity of preservative should be performed on a large scale, and insulin injection without preservative need to be produced and applied for patients with diabetes.