ESPE Yearbook of Paediatric Endocrinology

European Journal of Endocrinology (2020) 182, 559–567. doi: 10.1530/EJE-19-0646. PMID: 32337961 paolocavarzere@yahoo.it

These authors enrolled 80 prepubertal patients (46 boys; 34 girls) with idiopathic isolated GHD and normal brain MRI, who were treated with rhGH for at least two years. The data show that GH therapy could be safely stopped in the 55% who showed normal GH peak values when retesting was performed at the intermediate stage of puberty.

The last international consensus statement recommended re-testing for GH secretion in young adults with childhood-onset GHD (COGHD) and to continue GH replacement therapy, without the need for GH re-testing, in patients with more than three pituitary hormone deficits or with isolated GHD associated with an identified genetic mutation (1). The majority of patients with COGHD show normal GH secretion when re-evaluated at the end of growth (2). If transient prepubertal GH deficiency is postulated, it would be reasonable to retest GH secretion during puberty rather than at the end of growth.

In this study, clinical, auxological and biochemical parameters at five time points were analyzed in all patients: at diagnosis; after the first year of therapy; at the intermediate stage of puberty; at retesting and at the near-adult height. Treatment was discontinued when patients reached the intermediate stage of puberty. After 12 weeks from cessation of therapy, GH secretion was retested using the arginine stimulation test. GH was definitively discontinued after retesting GH in 44 children (55%) who showed a normal GH peak (≧8 μg/L) on retesting, and was restarted in 36 (45%) with persistent GHD. No significant differences were found in adult height or the delta height between genetic target and adult height between the two groups. IGF-1 SDS levels < −0.45 were indicative of persistent GHD (84% sensitivity, 63% specificity).

The authors conclude that in children with idiopathic isolated GHD, GH secretion should be retested at mid-puberty, as more than half of these patients show a normalization of GH secretion and GH therapy can be safely discontinued. The results of this study are consistent with previous reports on early retesting showing normalization of GH secretion during the transition phase in children with isolated idiopathic GHD (2).

Reference: 1. Ho KK. Consensus guidelines for the diagnosis and treatment of adults with GH deficiency II: a statement of the GH research society in association with the European society for pediatric endocrinology, lawson wilkins society, European society of endocrinology, Japan endocrine society, and endocrine society of Australia. Eur J Endocrinol. (2007) 157:695–700. 10.1530/EJE-07-0631 Alatzoglou KS, Dattani MT. Genetic forms of hypopituitarism and their manifestation in the neonatal period. Early Hum Dev. 2009;85(11):705–712.2. Penta L, Cofini M, Lucchetti L, Zenzeri L, Leonardi A, Lanciotti L, Galeazzi D, Verrotti A, Esposito S.Growth Hormone (GH) Therapy During the Transition Period: Should We Think About Early Retesting in Patients with Idiopathic and Isolated GH Deficiency? Int J Environ Res Public Health. 2019 Jan 23;16(3):307. doi: 10.3390/ijerph16030307.