Catch-up growth in autosomal dominant isolated growth hormone deficiency (IGHD type II).
OBJECTIVE
Data on the GH-induced catch-up growth of severely GH-deficient children affected by monogenetic defects are missing.


METHODS
Catch-up growth of 21 prepubertal children (6 females, 15 males) affected with IGHD type II was analyzed in a retrospective chart review. At start of therapy, mean age was 6.2 years (range, 1.6-15.0), mean height SDS was -4.7 (-7.6 to -2.2), mean IGF-I SDS was -6.2 (-10.1 to -2.2). GH was substituted using a mean dose of 30.5microg/kg*d.


RESULTS
Catch-up growth was characterized by a mean height gain of +0.92, +0.82, and +0.61 SDS after 1, 2, and 3 years of GH therapy, respectively. Mean height velocities were 10.7, 9.2 and 7.7cm/year during the first three years. Mean duration of complete catch-up growth was 6 years (3-9). Mean height SDS reached was -0.97 (-2.3 to +1.1), which was within the range of the estimated target height of -0.60 SDS (-1.20 to -0.15). The younger and shorter the children were at start of therapy the better they grew during the first year independent of the dose. Mean bone age was delayed at start by 2.1 years and progressed by 2.5 years during the first two years of therapy. Incomplete catch-up growth was caused by late initiation or irregular administration of GH in four cases.


CONCLUSIONS
Our data suggest that GH-treated children with severe IGHD show a sustained catch-up growth over 6 years (mean) and reach their target height range. This response to GH is considered to be characteristic for young children with severe growth retardation due to IGHD.
Binder
G
G
University-Children's Hospital, Pediatric Endocrinology Section, Hoppe-Seyler-Str. 1, 72076 Tuebingen, Germany. gerhard.binder@med.uni-tuebingen.de
Iliev
D I
DI
Mullis
P E
PE
Ranke
M B
MB
D000293:Adolescent; D001827:Body Height / Q000187:drug effects*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004393:Dwarfism, Pituitary / Q000188:drug therapy* / Q000235:genetics; D005260:Female; D005799:Genes, Dominant; D013006:Growth Hormone / Q000494:pharmacology / Q000627:therapeutic use*; D019382:Human Growth Hormone / Q000172:deficiency* / Q000235:genetics; D006801:Humans; D008297:Male; D009154:Mutation; D011994:Recombinant Proteins / Q000494:pharmacology / Q000627:therapeutic use*; D012189:Retrospective Studies
D011994:Recombinant Proteins; D019382:Human Growth Hormone; D013006:Growth Hormone