Is there an auxological basis for growth-promoting treatment with human growth hormone in short children?

Long-term treatment with growth hormone in short children with nephropathic cystinosis

OBJECTIVE

The objective was to assess the efficacy and safety of growth hormone (GH) treatment in severely growth retarded children with nephropathic cystinosis during conservative treatment and during renal replacement therapy.

STUDY DESIGN

The design was an open-labeled prospective trial with a run-in period of 1 year.

RESULTS

A total of 74 children with cystinosis (age 3.0 to 18 years) were treated with GH over a mean period of 3.1 years (range 1 to 10 years); 52 patients were receiving conservative treatment (mean age 7.1 years), 7 were receiving dialysis (12.5 years), and 15 had received a renal transplant (14.8 years). The mean standardized height (SD score) was -4.0 in the conservative treatment group, -4.4 in the dialysis group, and -4.9 in the renal transplant group. During the first treatment year, height velocity doubled in the conservative treatment group, increased by 80% in the dialysis group, and increased by 45% in renal transplant group. Within 3 years the height SD score increased by +1.6 (P <.001) in prepubertal patients receiving conservative treatment, and percentile parallel growth was maintained thereafter. These effects of GH were less expressed in peripubertal patients receiving renal replacement therapy. No major side effects were observed.

CONCLUSION

Long-term GH treatment is safe and effective in young children with nephropathic cystinosis. GH treatment should be started early in the course of the disease if adequate nutrition and cysteamine treatment do not prevent growth retardation.

Growth hormone treatment of short children born small for gestational age or with Silver-Russell syndrome: results from KIGS (Kabi International Growth Study), including the first report on final height

The response to growth hormone (GH) therapy was studied in children born small for gestational age (SGA; n = 593) and in those with Silver-Russell syndrome (SRS; n = 127) using data from KIGS (Kabi International Growth Study). For the SGA patients, median birth weight was -2.6 SD scores (SDS), treatment was started at a median age of 9.2 years, at a time when median height was -2.8 SDS while median target height was -1.4 SDS. For the SRS patients, median birth weight was -3.1 SDS, treatment was started at a median age of 7.0 years, at a time when median height was -3.4 SDS with a median target height of -0.1 SDS. GH treatment increased height SDS in both SGA children and patients with SRS; in 16 SGA patients treated to (near) final height with GH (median dose, 0.7 IU/kg/week), height minus target height SDS was -2.0 at the start of treatment and -1.0 at final height. In conclusion, the results obtained in KIGS indicate that GH treatment of short children born SGA is effective in increasing final height above the predicted height and in achieving the target height.

Growth hormone therapy in children with short stature: is bigger better or achievable?

The introduction of recombinant DNA-synthesized human growth hormone in the mid-1980s, and its attendant unlimited supply, have led to wider application of growth hormone therapy in children. Over the past decade, the efficacy of growth hormone treatment in patients with Turner syndrome and chronic renal insufficiency, two conditions in which growth hormone secretion is normal, in improving growth velocity and final height, has also led to the consideration of growth hormone therapy in children with idiopathic short stature. Although thousands of patients with idiopathic short stature are currently being treated with growth hormone, the limited overall results available at this time do not show a significant improvement in final adult height despite an improvement in short-term growth velocity. Potential reasons for this outcome include 1) skeletal age advancing more rapidly than height age, 2) heterogeneity of the patient population comprising idiopathic short stature, 3) inherent inaccuracies of methodological tools, such as measurement of predicted adult height, and 4) a subset of children with idiopathic short stature who may, in fact, have partial growth hormone insensitivity. From a psychological perspective, the consensus of investigations in non-clinic-referred populations of psychosocial function in children with short stature do not indicate a disadvantage compared with children of normal height when socio-economic status is taken into consideration. These results, in conjunction with the minimal gains reported in behavioural measurements in idiopathic short children treated with growth hormone, question the traditional rationale that augmentation of growth velocity results in improvement in psychosocial well-being.

Biosynthetic growth hormone therapy in children with growth hormone deficiency: experience at AIIMS, New Delhi

A total of 20 previously untreated children with growth hormone deficiency (GHD) were treated for one year with biosynthetic human growth hormone (hGH). The mean chronologic age was 9.43 +/- 3.52 years with a height age of 5.02 years, and bone age 9.43 +/- 3.52 (TW2-RUS) 6.42 years. The mean pretreatment growth velocity was 2.43 +/- 0.90 cm/year. Of these 14 children had complete GHD (peak GH levels less than 5 ng/ml) and 6 had partial GHD. They were treated with recombinant GH in a dose of 0.5 IU/kg/week divided into 6-7 injections per week subcutaneously at night. The mean growth velocity increased to 8.88 +/- 2.10 cm/yr at the end of 6 months and 8.00 +/- 2.21 cm/yr at 12 months. The actual gain ranged from 6-11 cm in a year. There were no local adverse reactions. One child developed vitiligo of the face and another transient hyperglycemia.

Growth response in prepubertal children with idiopathic growth hormone deficiency during the first year of treatment with human growth hormone. Analysis of the Kabi International Growth Study

In order that children with growth hormone deficiency (GHD) reach the goal of normal adult stature, treatment modalities need to be optimized. From the large database of patients enrolled in the Kabi International Growth Study (KIGS), 257 prepubertal patients with idiopathic GHD undergoing their first year of growth hormone (GH) substitution therapy were selected. A multiple regression analysis was performed to determine both auxiological factors characterizing the patients and the factors related to the chosen treatment modalities which are of significance for the observed magnitude of the growth response. Due to the structure of the data, pretreatment height velocity and bone age-derived auxiological data were not considered. It was observed that the magnitude of the growth response was inversely correlated with chronological age and relative height (HT SDS) at the start of GH treatment but was positively correlated with mid-parental height. The growth response was also positively correlated with the GH dose (IU/kg/week) and the frequency of GH injections per week. A regression equation using these five parameters was derived, allowing the growth response of these patients to be predicted. The extension of this analytical approach in the future will allow the treatment of patients with GHD to be tailored to individual requirements.