Recombinant human GH replacement therapy in children with pseudohypoparathyroidism type Ia: first study on the effect on growth.
BACKGROUND
Since the identification of GH deficiency due to resistance to GHRH in patients with pseudohypoparathyroidism type Ia (PHP-Ia), no study investigated the effects of recombinant human GH (rhGH) therapy on height velocity (HV) in these patients.


OBJECTIVE
To address this question, eight prepubertal PHP-Ia children with GH deficiency (seven girls and one boy, aged 5.8-12 yr) underwent a 3- to 8-yr treatment with rhGH. Height and HV were measured before and at 6-month intervals during therapy. Nine sex- and age-matched children with idiopathic GH deficiency were monitored during rhGH therapy for comparison.


RESULTS
In PHP-Ia children, height sd scores increased from -2.4 ± 0.58 to -1.8 ± 0.47 (P = 0.04) after 12 months, this increase being maintained after the second (-1.6 ± 0.6) and third (-1.15 ± 0.6) year of therapy, similarly to what recorded in children with idiopathic GH deficiency. The HV and HV sd scores after 3 yr maintained a significant increase from 3.5 ± 0.6 to 7.0 ± 0.9 cm/yr (P < 0.0001) and from -2.8 ± 0.8 to +2.2 ± 1.0 (P < 0.0001), respectively. Six patients treated for 4-8 yr had a reduced pubertal spurt and did not improve their near-adult height, with the only exception of one patient in whom estrogen production was blocked by GnRH analogs.


CONCLUSIONS
We report the first study on the efficacy of rhGH replacement therapy in prepubertal children with PHP-Ia and provide indication that treatment of GH deficiency should be started soon due to the rather limited time window for a potentially effective therapy.
Mantovani
Giovanna
G
Endocrinology Unit, Department of Medical Sciences, University of Milan, Fondazione Instituto di Ricovero e Cura a Carattere Scientifico Ca' Granda Policlinico, Milan, Italy. giovanna.mantovani@unimi.it
Ferrante
Emanuele
E
Giavoli
Claudia
C
Linglart
Agnes
A
Cappa
Marco
M
Cisternino
Mariangela
M
Maghnie
Mohamad
M
Ghizzoni
Lucia
L
de Sanctis
Luisa
L
Lania
Andrea G
AG
Beck-Peccoz
Paolo
P
Spada
Anna
A
D001827:Body Height / Q000187:drug effects*; D002648:Child; D002675:Child, Preschool; D005260:Female; D019382:Human Growth Hormone / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D011547:Pseudohypoparathyroidism / Q000628:therapy*; D011994:Recombinant Proteins / Q000627:therapeutic use*; D016896:Treatment Outcome
D011994:Recombinant Proteins; D019382:Human Growth Hormone