Changes of amino-terminal propeptide of C-type natriuretic peptide and growth velocity in patients with idiopathic short stature or isolated growth hormone deficiency after recombinant human growth hormone treatment

Objective To explore the value of amino-terminal propeptide of C-type natriuretic peptide (NTproCNP) in evaluating the efficacy of therapy with recombinant human growth hormone ( rhGH ) in patients with idiopathic short stature (ISS) and isolated growth hormone deficiency ( IGHD ).Methods Forty-eight prepubertal children( IGHD n=25,ISS n=23 ) treated for at least 1 year with rhGH were included.Serum insulin-like growth factor- Ⅰ ( IGF- Ⅰ ) and NTproCNP levels were measured before starting treatment and 6 months later.Twelve months after starting treatment,all patients were assessed and annual growth velocity ( GV ),height standard deviation score ( HTSDS),and gained HTSDS (△HTSDS) were recorded.Results In GHD group,positive relationships between GV and change of IGF- ISDS( △IGF- ISDS ),GV and change of NTproCNP concentrations(△NTproCNP) were found( r=0.407,P=0.044 ;r=0.490,P=0.013 ).GH peak value was also positively associated with IGF- ISDS and NTproCNP before therapy ( r =0.558,P =0.004; r =0.630,P =0.001 ).△IGF- ISDS and △NTproCNP were positively associated after therapy ( r =0.466,P =0.019 ).In ISS group,GV was associated with △NTproCNP ( r=0.845,P＜ 0.01 ).Conclusions NTproCNP is a novel biomarker of growth as its level increases during growth-promoting treatment.Furthermore,IGF- Ⅰ is also valuable in evaluating the efficacy of rhGH therapy in short stature patients. Key words: Growth hormone treatment;  Growth hormone deficiency;  Idiopathic short stature;  Insulinlike growth factor- Ⅰ ;  C-type natriuretic peptide