Incidence and predictors of persistent growth hormone deficiency (GHD) in patients with isolated, childhood-onset GHD

Introduction: In a considerable proportion of patients with childhood-onset growth hormone (GH) deficiency (GHD), a normalisation of GH secretion at the attainment of final height (FH) is observed. The aim of the present study was to assess the incidence of, and to find out the predictors of, persistent and transient GHD, available in the pre-treatment period, in patients with childhood-onset isolated, non-acquired GHD. Material and methods: The analysis comprised 150 short children (117 boys), with childhood-onset isolated, non-acquired GHD who completed GH therapy and attained FH. Before treatment and at FH (in retesting), auxological parameters were measured, GH peak in stimulation tests and IGF-I concentration were assessed, and pituitary height (PHt) was measured before treatment. Results: The incidence of persistent GHD was 12.0%. The patients with persistent GHD had before treatment significantly lower GH and IGF-I secretion, as well as significantly better increase of height SDS (Delta HSDS) during GH therapy than those with transient GHD. A negative correlation was observed between Delta HSDS and IGF-I concentration, but not between Delta HSDS and GH peak. There was no significant difference in the incidence of pituitary hypoplasia between the patients with persistent and transient GHD. Conclusions: The incidence of persistent GHD in patients with childhood-onset, isolated, non-acquired GHD is relatively low. Despite the fact that the predictors of persistent and transient GHD may be identified in childhood, a diagnosis of GHD should be verified in retesting after the attainment of FH in each case.