Growth of Two Children after Six Months Interruption of GH Therapy

Abstract

We describe two short boys with normal GH responses to the stimuli in whom GH therapy was interrupted for 6 months. Their growth rates before and after the interruption, and after readministration of GH were evaluated. Height velocity (HV) in case 1 before and after the interruption was 6.6cm/y and 5.0cm/y, respectively. HV was not increased (5.0cm/y) by re-initiation of GH therapy despite the high serum IGF-1 level. Height velocity (HV) in case 2 before and after the interruption was 5.6cm/y and 3.6cm/y, respectively. HV was slightly increased to 4.1cm/y by readministration of GH, but it was far below the pretreatment value. Serum IGF-1 was increased by GH in this case as well. We conclude that re-acceleration of growth by re-administration of GH after interruption of therapy, as seen in classical GHD patients, may not be expected in normal short children.