Diagnostic and therapeutic aspects of GH deficiency (GHD) in the transition period

INTRODUCTION Until the recognition of the impact of GH Deficiency (GHD) in adulthood, GH replacement therapy in children with GHD was discontinued at final height1. Now it is widely accepted that adults with GH deficiency (GHD) have impaired health, which improves with GH replacement2-6. Adult GHD syndrome is associated with changes in body composition, including increased fat mass, a possible reduction in bone mass, adverse changes in the blood lipid profile and cardiac function, reduced energy levels and reduced psychosocial well-being2-10. The diagnosis of GHD in adulthood is generally done in patients who have acquired GHD from pituitary or hypothalamic disease, or its treatment, in adult life4-6. GH therapy in adults has therefore been started with the long-term aim of reducing cardiovascular and osteoporotic risk, and the short-term aim of improving quality of life2,3,8-10. In fact it has been shown that these therapeutic end-points should be reached with an optimal rhGH replacement and now in many European countries and in US, GH therapy is allowed by the Ministries of Health. The considerable number of children who undergone GH therapy for classical and non classical GH deficiency implies the problem of considering who, when and how should continue the treatment in adulthood11-15. It is well known that, GH secretion physiologically declines after puberty16,17. Some children with less severe form of GHD may have adequate GH secretion in adulthood and will not suffer adverse consequences from the discontinuation of GH replacement therapy13. A percentage of children will, however, remains severely GH deficient in adulthood if treatment is discontinued12,14,18. Children with GHD are therefore at risk of being withdrawn from potentially beneficial GH replacement therapy on reaching final height. Aim of the present paper is to answer the following questions regarding the transition adolescent: