Endocrine Abstracts

Introduction: Lipoatrophy (LA) was common before the advent of recombinant human insulin. More recently, insulin analogues have been widely introduced into paediatric practice. In the literature, LA has only been reported so far with insulin Lispro (Lily, USA) (n=4 adult patients and 3 children) and insulin Glargine (Sanofi-Aventis, France) (n=1 adult patient). To our knowledge; this is the first report of LA with insulin Aspart (NovoRapid), biphasic insulin Aspart (Novomix 30) and insulin Detemir (Levemir) (Novo Nordisk, Denmark).

Case reports: Four children with type 1 diabetes were commenced on Novomix 30 (n=2) or Novorapid/Levemir injections (n=2). They developed LA at the injection sites after 2–3 years. One patient developed LA at the Novorapid site and the other at the Levemir site. The mean HbA1C ranged from 8.0–9.9%. Insulin antibody levels were high in 3/4. In 2/4, LA resolved by changing the injection site. It recurred at the new sites in 2 but resolved after changing the insulin preparation (Novomix 30 to Humalog mix25 and Levemir to insulin Glargine). HbA1C had steadily dropped to 7.4% along with the resolution of LA in one patient. LA resolved over a period of 1–2 years in all patients.

Discussion: The pathogenesis of LA is poorly understood. The suggested mechanisms are: repeated mechanical trauma from the injections, cryotrauma from refrigerated insulin or immune mediated. In 2/4, LA resolved after changing the injection site suggesting that local factors could be the cause of LA. It is our practice to examine the injection sites on each visit and this facilitated early detection of LA.

Conclusion: LA is a rare complication of treatment with insulin analogues. It may be sufficient to change the injection site to manage LA. If that is not effective, changing to an alternative analogue was successful in our experience.