GH therapy in Noonan syndrome: Review of final height data.

Background and aims: Several studies, despite using small cohorts, have shown a short-term improvement in the height velocity of short children with Noonan syndrome (NS) when treated with recombinant growth hormone (GH). However, the question is whether or not this improvement is sustained until adult height is reached. This paper reviews the few studies reporting final height data of GH treatment in individuals with NS.

Methods: Review of published papers from 4 main and several small studies with final height data after GH treatment in NS.

Results: The range of height gain to adult age varies between 0.6 and 2.0 SDS, depending on genotype, age at start of treatment, duration of treatment and which growth charts are used. The younger the age at which treatment is started, the better the result. There seems to be a correlation between growth response and genotype, with a diminished growth response when the PTPN11 mutation is present.

Conclusion: Data on the benefits of GH treatment during childhood and adolescence upon the final height are encouraging in individuals with NS. There is a substantial height gain during prepubertal years, which continues during the pubertal period, reaching a final height within the normal population in the majority of previously short individuals with NS.