Endocrine Abstracts

Introduction: Children with Laron’s syndrome have a classical phenotype which includes extreme short stature and mid facial hypoplasia. It is biochemically characterised by high levels of GH and very low IGF1 levels. These children fulfil the criteria for recombinant IGF1 (rhIGF1, Mecasermin) therapy, however this has to be balanced with possible side effects. This study looked at the short term efficacy and safety profile of six children (five males) with Laron’s syndrome who are receiving rhIGF1 therapy in a single regional centre.

Methods: Case notes of all children with Laron’s syndrome on rhIGF1 treatment within a single regional centre were reviewed with the primary outcomes being change in height SDS and adverse events.

Results: The median age of initiation of treatment was 9.1 years with median height SDS at start of treatment of −4.9 SDS. The starting dose was 0.04 mg/kg b.d. with dose titration to a maximum of 0.12 mg/kg b.d. over 2–6 months. Duration of treatment has ranged from 0.4 to 1.9 years. The median height increase in four children who have received at least 1 year of treatment was 0.46 SDS. Pre-treatment assessments revealed additional problems in five children (coeliac disease, otitis media, hypercholesterolaemia, pelvic-ureteric obstruction, learning difficulties). The most common adverse events included injection site hypertrophy (4), headaches (2), snoring (1), tonsillar hypertrophy (1) and hair loss (1).

Conclusion: This group of children with Laron’s syndrome had a range of additional incidental pathologies and therefore may need increased vigilance irrespective of treatment. RhIGF1 therapy in children with Laron’s syndrome has some short term benefit on height SDS scores, with most adverse events related to injection site hypertrophy. Longer term monitoring is essential to provide further information on height outcomes and safety data.