Porcine insulin lipoatrophy

Jones GR, Statham B, Owens DR, Jones MK, Hayes TM. Lipoatrophy and monocomponent porcine insulin. BMJ (Clin Res Ed) 1981 282(6259) 190. 

Insulin, administered subcutaneously, may cause either lipoatrophy or lipohypertrophy. Lipoatrophy is the breakdown of adipose tissue at the insulin injection site causing a depression in the skin at the injection site and occasionally at distant sites also. It may be the result of an immune response or the use of less than pure insulin. Some findings suggest that total lipodystrophy syndrome results from the inflammatory destructive process of adipose tissue (Yanagawa et al., 1990). Injection of human or purified porcine insulin into the site over a 2-4-week period may result in subcutaneous fat accumulation. 

Before purified human insulins were available, lipoatrophy occurred in about 25% of insulin-treated patients. Improvement or resolution of lesions has been noted in most patients after changing to purified porcine insulin. 

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