Height Outcome of the Recombinant Human Growth Hormone Treatment in Subjects with Noonan Syndrome: A Meta-AnalysisFrancesco Massart1*, Silvano Bertelloni1, Mario Miccoli2 and Angelo Baggiani2
- *Corresponding Author:
- Francesco Massart
Pediatric Unit, Maternal and Infant Department
St. Chiara University Hospital of Pisa, Italy
Tel: +39050 992 602
Fax: +39050 992 950
E-mail: [email protected]
Received date: February 25, 2014; Accepted date:September 03, 2014; Published date: September 09, 2014
Citation: Massart F, Bertelloni S, Miccoli M, Baggiani A (2014) Height Outcome of the Recombinant Human Growth Hormone Treatment in Subjects with Noonan Syndrome: A Meta-Analysis. J Genet Syndr Gene Ther 5:238. doi:10.4172/2157-7412.1000238
Copyright: © 2014 Massart F, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Children with Noonan Syndrome (NS) present variable growth impairment associated to facial dysmorphology and cardiovascular anomalies. Mutations in several genes of RAS/MAPK signaling pathway have been identified, likely impairing Growth Hormone (GH) sensitivity. If untreated, these patients often remain short in adulthood. Although Recombinant Human GH (rhGH) treatment improves short-term linear growth, poor data on the Final Height (FHt) of rhGH-treated subjects with NS are available. After thorough search of the published literature for pertinent studies, a meta-analysis evaluation of the efficacy and safety of rhGH treatment in NS patients were performed. In total sample (n=885; 70.0% males), administration of rhGH progressively improved height pattern, but relevant catch-up growth was not shown. The rhGH-induced growth improvement appeared until FHt [n=168; –2.151 SDS (95%CI –2.792 to –1.511)]. During 1st year of rhGH treatment, height velocity gain meta-correlated with serum insulin-like growth factor 1 (IGF1) increment [n=31; r=0.685 (95%CI 0.419 to 0.843); P<0.0001] while negative meta-correlation was detected between age at rhGH start and height velocity [n=48; r=–0.608 (95%CI –0.765 to –0.383); P<0.0001]. Height gain after 1-yr rhGH treatment (dosage range 0.35-0.46 mg/kg/wk) was higher in NS patients without protein tyrosine phosphatase non-receptor type 11 (PTPN11) gene mutation [n=33; 0.903 SDS (95%CI 0.552 to 1.254)] than that observed in subjects positive for PTPN11 mutations [n=62; 0.606 SDS (95% CI 0.274 to 0.938); P<0.0001]. While few serious adverse events were reported during rhGH treatment, causal relationship to rhGH therapy was unlikely. In conclusion, this meta-analysis indicates that rhGH treatment progressively improved height outcome of short children with NS. Future studies using carefully titrated rhGH protocols are need to optimize treatment protocols and establish possible risks, if any, leading to clear indications for practice and regulatory agencies.