Characterization and prevalence of severe primary IGF1 deficiency in a large cohort of French children with short stature

OBJECTIVE

The prevalence of severe primary IGF1 deficiency (IGFD) is unclear. IGFD must be identified promptly as treatment with recombinant human IGF1 (rhIGF1) is now available. Our objective was to characterize and assess the prevalence of severe primary IGFD in a large cohort of patients evaluated for short stature at a pediatric endocrinology unit in France.

DESIGN

Observational study in a prospective cohort.

METHODS

Consecutive patients referred to our unit between 2004 and 2009 for suspected slow statural growth were included. Patients were classified into eight etiological categories. IGFD was defined by height ≤-3 SDS, serum IGF1 levels <2.5th percentile, GH sufficiency, and absence of causes of secondary IGFD.

RESULTS

Out of 2546 patients included, 337 (13.5%) were born small for gestational age and 424 (16.9%) had idiopathic short stature. In these two categories, we identified 30 patients who met our criterion for IGFD (30/2546, 1.2%). In these 30 patients, we assessed the response to IGF1 generation test, time course of IGF1 levels, and efficiency of GH replacement therapy. The results indicated that only four of the 30 children were definite or possible candidates for rhIGF1 replacement therapy.

CONCLUSION

The prevalence of severe primary IGFD defined using the standard criterion for rhIGF1 treatment was 1.2%, and only 0.2% of patients were eligible for rhIGF1 therapy.

Unexpected high frequency of skeletal dysplasia in idiopathic short stature and small for gestational age patients

OBJECTIVE

To assess the prevalence of skeletal dysplasias (SDs) in patients with idiopathic short stature (ISS) or small for gestational age (SGA) status.

SETTING

Rare Endocrine/Growth Diseases Center in Paris, France.

DESIGN

A prospective study on consecutive patients with ISS and SGA enrolled from 2004 to 2009.

METHOD

We used a standardized workup to classify patients into well-established diagnostic categories. Of 713 patients with ISS (n=417) or SGA status (n=296), 50.9% underwent a skeletal survey. We chose patients labeled normal or with a prepubertal slowdown of growth as a comparison group.

RESULTS

Diagnoses were ISS (16.9%), SGA (13.5%), normal growth (24.5%), transient growth rate slowing (17.3%), endocrine dysfunction (12%), genetic syndrome (8.9%), chronic disease (5.1%), and known SD (1.8%). SD was found in 20.9% of SGA and 21.8% ISS patients and in only 13.2% in our comparison group. SD prevalence was significantly higher in the ISS group than in the comparison group, especially (50%) for patients having at least one parent whose height was <-2 SDS. Dyschondrosteosis and hypochondroplasia were the most frequently identified SD, and genetic anomaly was found in 61.5 and 30% respectively. Subtle SD was found equally in the three groups and require long-term growth follow-up to evaluate the impact on final height.

CONCLUSION

SD may explain more than 20% of cases of growth retardation ascribed to ISS or SGA, and this proportion is higher when parental height is <-2 SDS. A skeletal survey should be obtained in patients with delayed growth in a context of ISS or SGA.

Childhood craniopharyngioma: hypothalamus-sparing surgery decreases the risk of obesity

CONTEXT

Craniopharyngioma is a brain tumor whose high local recurrence rate has for a long time led to a preference for extensive surgery. Limited surgery minimizing hypothalamic damage may decrease the severe obesity rate at the expense of the need for radiotherapy to complete the treatment.

OBJECTIVE

We compared weight gain and local recurrence rates after extensive resection surgery (ERS) and hypothalamus-sparing surgery (HSS).

DESIGN

Our observational study compared a historical cohort managed with ERS between 1985 and 2002 to a prospective cohort managed with HSS between 2002 and 2010.

SETTING

The patients were treated in a pediatric teaching hospital in Paris, France.

PATIENTS

Thirty-seven boys and 23 girls were managed with ERS (median age, 8 years); 38 boys and 27 girls were managed with HSS (median age, 9.3 years).

MAIN OUTCOME MEASURES

Data were collected before and 6 months to 7 years after surgery. Body mass index (BMI) Z-score was used to assess obesity and the number of surgical procedures to assess local recurrence rate.

RESULTS

Mean BMI Z-score before surgery was comparable in the 2 cohorts (0.756 after ERS vs 0.747 after HSS; P = .528). At any time after surgery, mean BMI Z-score was significantly lower after HSS (eg, 1.889 SD vs 2.915 SD, P = .004 at 1 year). At last follow-up, the HSS cohort had a significantly lower prevalence of severe obesity (28% vs 54%, P < .05) and higher prevalence of normal BMI (38% vs 17%, P < .01). Mean number of surgical procedures was not significantly different in the 2 cohorts.

CONCLUSIONS

Hypothalamus-sparing surgery decreases the occurrence of severe obesity without increasing the local recurrence rate.

Social and psycho-intellectual outcome following radical removal of craniopharyngiomas in childhood. A prospective series

BACKGROUND

A prospective study on childhood craniopharyngiomas (CPs) was conducted from 1994 to 1998 to appreciate the pre- and postoperative clinical, endocrine, mental, and intellectual status of the patients and to determine the incidence and severity of the postoperative hypothalamic syndrome.

METHODS

The series included 14 consecutive CPs. Twelve were retrochiasmatic and intraventricular, and two were partly prechiasmatic and extraventricular. All were treated with the aim of "total" removal. The removal was "total" in nine cases but incomplete in the other five. Immediate postoperative follow-up was uncomplicated in all cases.

CONCLUSION

At 2-year follow-up, the two children with an extraventricular CP and a "total" tumor removal were intellectually normal, had no hypothalamic syndrome, and attended normal school with good results. The 12 others, although still intellectually normal, were more or less severely affected by a hypothalamic syndrome which altered their social insertion and caused academic failure. The authors conclude from this study that radical surgery should be reserved to extraventricular CPs only.

Follow-up of 68 children with congenital adrenal hyperplasia due to 21-hydroxylase deficiency: relevance of genotype for management

The phenotype of congenital adrenal hyperplasia (CAH) varies greatly. The purpose of this study was to optimize diagnosis and follow-up by comparing phenotype with genotype. Sixty-eight patients with CAH due to 21-hydroxylase deficiency were studied by clinical, hormonal, and molecular genetic methods. Patients were classified according to predicted mutation severity: group 0, null mutation (17.6%); group A, homozygous for IVS2 splice mutation or compound heterozygous for IVS2 and null mutations (33.8%); group B, homozygous or compound heterozygous for I172N mutation (14.7%); group C, homozygous or compound heterozygous for V281L or P30L mutations (26.5%); and group D, mutations with unknown enzyme activity (7.4%). All group 0 and A patients had the salt-wasting form, and group C had nonclassical forms. Group B included five salt-wasting and five simple virilizing forms. Groups 0 and A were younger at diagnosis (P < 0.02), and females were more virilized than those in group B. Group B had higher basal plasma 17-hydroxyprogesterone (564 +/- 162 nmol/liter) and testosterone (11 +/- 3 nmol/liter) levels than group C [59 +/- 13 nmol/liter (P < 0.001) and 1.4 +/- 0.2 nmol/liter (P < 0.005), respectively]. Hydrocortisone doses given to groups 0, A, and B were similar at all ages, but lower in group C (P < 0.01). Final height was below target height in classical (n = 16; -2 +/- 0.2 SD score; P < 0.02) and nonclassical (n = 11; -1.2 +/- 0.4 SD score; P < 0.03) forms. The severity of the genetic defects and the clinical-laboratory features are well correlated. Genotyping, combined with neonatal screening and optimal medical and surgical treatment, can help in the management of CAH.

Metrorrhagia and precocious puberty revealing primary hypothyroidism in a child with Down's syndrome

We report a child with Down's syndrome in whom metrorrhagia and precocious puberty revealed primary autoimmune hypothyroidism. The patient had a decreased growth velocity, exaggerated weight gain, bone age delay, and bilaterally enlarged multicystic ovaries. Delays in the diagnosis and treatment of hypothyroidism can lead to this peculiar presentation.

Idiopathic growth hormone deficiency: presentation, diagnostic and treatment during childhood

The clinical and biological presentation of idiopathic growth hormone (GH) deficiency (GHD) varies greatly, demonstrating the variety of its pathogenic features and explaining why it is difficult to diagnose. We examined 48 patients (26 males) with certain idiopathic GHD diagnosed at 4.8 +/- 0.7 yr. The symptoms that led to the diagnosis of GHD were low growth rate (33 cases), hypoglycemia (12 cases), microphallus (1 case) and in 2 cases the GHD was diagnosed from magnetic resonance imaging (MRI) performed for delayed mental development (1 case), or congenital blindness (1 case). The 2 other cases were diagnosed from routine GH evaluation performed at birth because of idiopathic GHD in siblings. Thirteen had congenital malformation. Twenty three cases (48%) had features suggesting that the GHD was of antenatal origin. Six of them were born by breech delivery. Twenty one cases (44%) had features suggesting a hypothalamic origin. The decrease in growth rate occurred before 0.5 year in 21 (55%), before 1 year in 27 (71%) and before 2 years in 30 (79%): 8 patients (21%) maintained a normal growth rate after this age. Among these 8 patients, 5 had signs suggesting an antenatal origin and 4 had severe episodes of hypoglycemia from birth. The mean GH peak after the pharmacological stimulation test was 3.6 +/- 0.5 micrograms/l. The mean plasma insulin-like growth factor 1 (IGFI) was 0.1 +/- 0.02 U/ml. The GH deficiency was associated with deficiencies of thyrotropin in 26 (54%) and of adrenocorticotrophic hormone in 17 (35%) patients. Among the 15 patients of pubertal age, 9 (60%) had gonadotrophin deficiency. No patient had diabetes insipidus. The MRI showed pituitary stalk interruption syndrome in 39 patients and normal pituitary anatomy in 6 patients. GH treatment reduced the difference between target and actual heights from 3.5 SD (before) to I SD (after 3 years) in the 39 more recently seen patients given 0.5-0.6 U/kg/w GH in 6 or 7 weekly injections. Height gain during the first year and cumulative height gain over 3 years (SD) was correlated negatively with height (SD) at the start of treatment (p < 0.01). We conclude that most of the patients with GHD have features suggesting an antenatal origin. Despite this early origin, the decreased growth rate may occur after 2 years.

Growth after bone marrow transplantation in young children conditioned with chemotherapy alone

Short stature is a potential side-effect of BMT, brought about by the conditioning protocol and/or the complications of BMT. This study evaluates the effects of conditioning by chemotherapy, and BMT complications on growth. Thirty children conditioned for BMT by chemotherapy alone (cyclophosphamide and busulfan) were classified according to the occurrence of serious or prolonged complications after BMT: group 1 (n = 12) had no complication, while group 2 (n = 18) did. Fifteen of them were severely growth retarded (< or = -2 s.d.) at BMT, because of their initial disease. At the time of BMT, the two groups had similar ages (1.0 +/- 0.2, s.e.m. year, in group 1 and 1.7 +/- 0.5 year in group 2), height (-1.7 +/- 0.5; -1.8 +/- 0.3 s.d.) and plasma insulin-like growth factor I (IGFI) levels (0.3 +/- 0.1 U/ml in both). Group I grew significantly and their plasma IGFI increased but group 2 did not, as assessed 2 years post-BMT. We conclude that conditioning with chemotherapy alone does not prevent the catch-up growth induced by BMT in young children; the lack of catch-up growth is due to complications occurring after BMT, and the change in plasma IGFI suggests that complications of BMT prevent any increase in plasma IGFI, and thereby catch-up growth.