Abstract Ref Number = APCP25
Effects of Growth Hormone (GH) in Children with Familial Short Stature (FSS), Idiopathic Short Stature (ISS) and Constitutional Delay of Growth and Puberty (CDGP).
Department of Pediatrics, University of Chieti, Italy
Short stature is the most common cause of referral to pediatric endocrinology units, though the vast majority of short children have variants of growth such as idiopathic short stature (ISS), constitutional delay of growth and puberty (CDGP) and familial short stature (FSS).
For the management of the child with short stature, the auxological sub-classification is helpful. With respect to the diagnostic process, in a child with FSS (if pathological causes of parental short stature are considered unlikely) the chance of finding a pathological disorder is low. Thus, the full set of diagnostic investigations may not be necessary, unless growth rate slows down, and these children attain their genetic potential. If a child’s height SDS is lower than the target range (NFSS) and there is a positive family history of CDGP, the likelihood of CDGP is high, and the clinician may follow the child growth carefully. Therefore, ISS is a diagnosis that is not based on positive findings in the diagnostic work-up, but on exclusion of other recognizable conditions. More specifically, children with ISS should be considered GH sufficient, should have normal body proportions, no history of a low birth size (small for gestational age, SGA), no chromosomal abnormalities, no dysmorphic syndromes and no systemic, endocrine or nutritional diseases.
A careful review of the diagnostic approach to short stature over the last 50 years would inevitably lead to the conclusion that rather than diagnosis dictating therapy, the availability of GH dictates diagnosis. Since recombinant GH has become widely available (1985), its indications are substantially increased.
Therefore, the initial GH replacement therapy limited to GH deficient patients,in some cases has changed into a pharmacological therapy to include different conditions of non-GH deficient short stature. The rationale of this treatment is based on the empiric observation of growth acceleration in response to GH administration, rather than on a pathophysiological approach. From a biological perspective, the close relation between GH dose and response to therapy, in terms of growth acceleration, is well established and confirms the clinical finding of excessive height gain in children with hypersecretion of GH-the more GH, the more growth. Anyhow, caution is mandatory when treating with GH a non-GH deficient child.
The aim of this discussion is to provide a critical overview on the effects of GH in three paradigmatic conditions of short stature which are idiopathic short stature (ISS), familial short stature (FSS) and constitutional delay of growth and puberty (CDGP) highlighting the available strength of scientific evidences for efficacy and safety.