Is retesting in growth hormone deficient children really useful?
BACKGROUND
Patients with childhood-onset GH deficiency (GHD) are usually retested after achievement of near final height, to verify whether they need to continue GH treatment. We investigated if GH stimulation test is necessary to confirm a persistent status of GHD or if other parameters could be a reliable predictor of GHD persistence.


METHODS
One-hundred and sixty-four children with idiopathic GHD (55 females and 109 males) were retested when they reached near final height using GH releasing hormone (GHRH)+arginine test or arginine alone.


RESULTS
At diagnosis, 23.8% of patients showed severe GHD (GH peak at diagnosis <5 ng/mL) and 76.2% showed partial GHD (GH peak <10 ng/mL). At time of retesting, 82.1% of severe GHD and 82.4% of partial GHD patients showed transient GHD. IGF-I levels were not different between persistent (0.18±1.18 SDS) and transient GHD subjects (0.17±0.82 SDS). Furthermore, among persistent severe GHD patients only two showed very reduced levels of IGF-I (<-2.0 SDS).


CONCLUSIONS
The majority of patients idiopathic GHD proved to be transient. IGF-I levels alone do not discriminate subjects with persistent from those with transient GHD. Therefore, after the end of GH substitutive treatment, a re-evaluation of GH secretion is mandatory to verify the persistence of GHD in adulthood.
Pediatrics and Adolescentology Unit, Internal Medicine and Therapeutics Department, University of Pavia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
Cristina
C
Meazza
University of Pavia, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
Chiara
C
Gertosio
Pediatrics and Adolescentology Unit, Internal Medicine and Therapeutics Department, University of Pavia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy.
Sara
S
Pagani
Department of Pediatrics, Auxoendocrinology Centre, University of Brescia, Spedali Civili, Brescia, Italy.
Alba
A
Pilotta
Clinical Epidemiology and Biometric Unit, IRCCS Policlinico San Matteo Foundation, Pavia, Italy.
Carmine
C
Tinelli
Department of Pediatrics, &quot;Carlo Poma&quot; Hospital, Mantova, Italy.
Fabio
F
Buzi
Pediatric Unit, Department of Life Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy.
Giovanni
G
Farello
Division of Pediatrics, Department of Health Sciences, University of &quot;Piemonte Orientale Amedeo Avogadro&quot;, Novara, Italy.
Giulia
G
Genoni
Division of Pediatrics, Department of Health Sciences, University of &quot;Piemonte Orientale Amedeo Avogadro&quot;, Novara, Italy.
Gianni
G
Bona
Pediatrics and Adolescentology Unit, Internal Medicine and Therapeutics Department, University of Pavia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy - mauro.bozzola@unipv.it.
Mauro
M
Bozzola
D000293:Adolescent; D001827:Body Height; D004393:Dwarfism, Pituitary / Q000175:diagnosis / Q000188:drug therapy; D005260:Female; D013006:Growth Hormone / Q000627:therapeutic use; D019382:Human Growth Hormone / Q000097:blood* / Q000172:deficiency*; D006801:Humans; D007018:Hypopituitarism / Q000175:diagnosis / Q000188:drug therapy; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis
D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone