Auxology and response to growth hormone treatment of patients with intrauterine growth retardation or Silver-Russell syndrome: analysis of data from the Kabi Pharmacia International Growth Study

Using the database from the Kabi Pharmacia International Growth Study, 105 patients with intrauterine growth retardation (IUGR) (82 males, 23 females) and 45 with Silver-Russell syndrome (SRS) (32 males, 13 females) with persistent postnatal growth failure were studied. Patients with IUGR had a birth length and birth weight more than 2 SD below the mean for gestational age. Their height deficit at the start of GH treatment was -3.0 SDS at a median chronological age of 8.7 years and a median bone age of 7.0 years. Mean paternal and maternal heights were 166 and 153 cm, respectively. The median dose of GH was 0.5 IU/kg/week, given at a median frequency of five injections/week. The median height SDS for chronological age after 1, 2 and 3 years of GH treatment were -2.5, -2.1 and -1.9, respectively. In the 45 patients with SRS, median chronological age and median bone age at the start of treatment were 6.7 and 3.2 years, respectively, and mean paternal and maternal heights were 167.5 and 160 cm, respectively. The median dose of GH was 0.7 IU/kg/week, given at a median frequency of six injections/week. The median height SDS for chronological age at the start of treatment and after 1, 2 and 3 years were -3.5, -2.9, -2.8 and -2.2, respectively. Although the criteria used by physicians when diagnosing SRS were not controlled or verified in this study, it appears that patients with SRS can be differentiated from those with IUGR with persistent growth failure by their reduced bone age for chronological age at the start of treatment, and by the fact that patients with SRS tended to be born to parents of normal height. GH treatment in both groups induced catch-up growth, though long-term follow-up studies will be required to assess the effects of treatment on final height.