Response to growth hormone with respect to pubertal status on increased dose in idiopathic growth hormone deficiency: an analysis of Turkish children in the KIGS database (Pfizer International Growth Study)

AIM

To compare the growth response to growth hormone (GH) treatment in patients with idiopathic GH deficiency (IGHD) who were prepubertal with the response of those who were pubertal at the onset of GH therapy on an increased GH dose.

PATIENTS AND METHODS

Among the Turkish patients enrolled in the Pfizer International Growth Study (KIGS) database with the diagnosis of IGHD, the growth data over 2 years of GH therapy were analyzed longitudinally of 113 (79 M) prepubertal (Group 1) and 44 (33 M) pubertal (Group 2) patients. Pubertal signs were reported to be present initially or to have appeared within 6 months of GH therapy in Group 2. Mean +/- SD age at onset of therapy was 8.7 +/- 3.5 and 13.5 +/- 1.8 years; height SDS -4.2 +/- 1.4 and -3.2 +/- 1.1 (p < 0.05) in Groups 1 and 2, respectively. Mid-parental height (MPH) SDS did not show a significant difference between the two groups (-1.5 +/- 1.1 vs -1.7 +/- 1.1).

RESULTS

Delta height SDS over 2 years of therapy was significantly higher in Group 1 (1.1 +/- 1.0) than in Group 2 (0.7 +/- 0.6) (p <0.05) in spite of a significantly lower dose of GH (14.6 +/- 3.3 in Group 1 vs 17.0 +/- 3.1 IU/m2/week in Group 2, p < 0.05). Ht--MPH SDS showed an increase from -2.4 +/- 1.7 to -1.4 +/- 1.5 in Group 1 and from -1.5 +/- 1.5 to -0.8 +/- 1.3 in Group 2. Overall delta height SDS showed negative correlations with age (r = -0.32), height SDS (r = -0.41) and height--MPH SDS (r = -0.40) at onset of therapy (p < 0.001).

CONCLUSIONS

These data show that in IGHD the slight increase (15-20%) in the dose of GH during puberty was not adequate to maintain height velocity at the same magnitude as in prepuberty, and thus was not cost effective.

Diagnostic value of pituitary MRI in differentiation of children with normal growth hormone secretion, isolated growth hormone deficiency and multiple pituitary hormone deficiency

Pituitary height, volume and morphology were investigated by MRI in patients aged 3.5-24.9 years with growth hormone deficiency (GHD) in relation to birth history and hormonal findings. Three groups with comparable age, sex and pubertal stage were studied: group I (n=42)--patients with isolated growth hormone deficiency (IGHD); group II (n=22)-- patients with multiple pituitary hormone deficiency (MPHD); and group III (n=30)--healthy controls. Pituitary height and volume differed significantly between the three groups, with the smallest in group II and largest in group III (p <0.001 for both). Both variables correlated significantly with peak GH value in the patient groups (p <0.001). The specificity of pituitary dysmorphology in the determination of GHD was 100% and its sensitivity in differentiation of IGHD and MPHD was 95%. Ectopic neurohypophysis was present in 75% of breech births and 27% of head-presenting patients (p <0.01). This study emphasizes the differential diagnostic value of pituitary MRI and its contribution to the understanding of the pathogenesis and prognosis in GHD.

Real-time sonography for screening of gallbladder dysfunction in children with type 1 diabetes mellitus

The aim of this study was to evaluate the occurrence of gallbladder dysfunction in children with type 1 diabetes mellitus using real-time ultrasonography. The study population consisted of 20 diabetic children (11 male, 9 female; age 11.7+/-2.8 years; diabetes duration 0.5-7 years) with clinically negative neuropathy findings and 15 healthy controls (11 male, 4 female; age 10.5+/-3.7 years). Three-dimensional measurements of the gallbladder were made before and 15, 30, 45, 60 min after intake of diet chocolate. Gallbladder volumes were calculated by the ellipsoid formula. Fasting gallbladder volume of diabetic children (16.9+/-9.5 ml) was significantly greater than that of the controls (10.6+/-5.3 ml; p=0.017). Ejection fraction and maximal contraction showed no significant difference between the two groups. Diabetic patients with multiple microvascular complications had diminished gallbladder motility. There was a negative correlation between BMI and maximal contraction (p<0.05). Nerve conduction velocity was diminished in 45% of the diabetic patients. In conclusion, gallbladder function is preserved in pediatric type 1 diabetic patients with a disease duration less then 10 years, but dilated gallbladder at rest may be an early sign of gastrointestinal autonomic neuropathy and a risk factor for gallstone formation.

A comparison of the use of premixed insulins in pen-injectors with conventional patient-mixed insulin treatment in children and adolescents with IDDM. Is there a decreased risk of night hypoglycemia?

Insulin injection is a problem in pediatric and adolescent age, and premixed insulin therapy given in pen-injectors (Novopen II) is expected to increase compliance. Compliance with treatment and safety of this kind of insulin substitution was investigated in 20 IDDM patients (8.2-19.6 years old). The study was of randomized cross-over design and its duration was 6 (2x3) months. Metabolic parameters were compared between premixed insulin therapy via pen-injector and patient-mixed insulin therapy via conventional syringe, and no differences were observed except for the postponing of night hypoglycemic attacks to 07.00 a.m. during premixed insulin therapy. No technical or medical problems occurred. Patients were more satisfied with the new therapy regimen as determined by questionnaire. We concluded that this kind of insulin substitution is safe in pediatric and adolescent IDDM patients.