Tall stature and duplication of the insulin-like growth factor I receptor gene

Trisomy of 15q26-qter is frequently associated with tall stature and mental retardation. Here we describe a patient with such trisomy, without a partial monosomy of another chromosome. The tall stature in this patient is most probably caused by duplication of the IGF1R gene. A duplication of the IGF1R gene is not a frequent finding in patients with tall stature. In 38 patients with features of Sotos syndrome without NSD1 alterations, a duplication was found only once. This patient was already known to have an unbalanced 2;15 translocation. Looking for a duplication of the 15qter region is still worth consideration in patients with tall stature and features of Sotos syndrome without an NSD1 alteration, especially when there is craniosynostosis or marked speech delay.

Genetic Disorders in the Growth Hormone – Insulin-Like Growth Factor-I Axis

In the last few years, our knowledge of genetically determined causes of short stature has greatly increased by reports of challenging patients, who offered the opportunity to study genes that play a role in growth. Since the first paper that showed the etiology of Laron syndrome [Godowski PJ, et al: Proc Natl Acad Sci USA 1989;86:8083-8087], many mutations in the growth hormone (GH) receptor have been identified. Recently, new mutations or deletions have been found in several components of the GH-insulin-like growth factor-I (IGF-I) axis: a homozygous mutation of the GH1 gene, resulting in a bio-inactive GH; mutations in the STAT5b gene, which plays a major role in the GH signal transduction; a homozygous missense mutation in the IGF-I gene; heterozygous mutations in the IGF-I receptor gene and a homozygous deletion of the acid-labile subunit gene. In this mini review, we describe the clinical and biochemical features of these genetic defects. Genetic analysis has become essential in the diagnostic workup of a patient with short stature. However, regarding the time consuming nature of molecular analysis, it is important to carefully select the patient for specific genetic evaluation. To help in this selection process, we developed flowcharts, based on the recently described patients, that can be used as guidelines in the diagnostic process of patients with severe short stature of unknown origin.

A variable degree of intrauterine and postnatal growth retardation in a family with a missense mutation in the insulin-like growth factor I receptor

CONTEXT

The type 1 IGF-I receptor (IGF1R) mediates the biological functions of IGF-I. Binding of IGF-I to the IGF1R results in autophosphorylation of the intracellular beta-subunit and activation of intracellular signaling.

OBJECTIVE

The objective of this study was to evaluate the functional characteristics of a novel IGF1R mutation and describe the phenotypic features of two patients with this mutation.

DESIGN

The study was performed in a university hospital.

PATIENTS

We describe a 35-yr-old female with mild intrauterine growth failure, progressive postnatal growth retardation, severe failure to thrive, and microcephaly. Her daughter was born with severe intrauterine growth retardation and also showed postnatal failure to thrive and microcephaly.

RESULTS

We found a heterozygous G3148-->A nucleotide substitution in the IGF1R gene, changing a negatively charged glutamic acid at position 1050 into a positively charged lysine residue (E1050K). E1050 is a conserved residue in the intracellular kinase domain. Dermal fibroblasts of the mother showed normal binding of iodinated IGF-I, but autophosphorylation and activation of downstream signaling cascades upon challenging with IGF-I was markedly reduced. Consequently, the maximal [(3)H]thymidine incorporation upon challenge with a dose range of IGF-I was reduced compared with a panel of control cells (3.65 +/- 1.79-fold vs. 6.75 +/- 4.7-fold stimulation; P < 0.01). These data suggest that the mutation results in the inactivation of one copy of the IGF1R gene.

CONCLUSIONS

These two patients support the key role for IGF-I in intrauterine and postnatal growth. The different phenotypes of these and earlier described patients may be associated with variability in IGF-I signaling. The degree of intrauterine growth retardation may be partially determined by the presence or absence of maternal IGF-I resistance.

Psychosocial, cognitive, and motor functioning in patients with suspected Sotos syndrome: a comparison between patients with and without NSD1 gene alterations

The aim of this study was to investigate psychosocial, cognitive, and motor functioning in patients clinically suspected of Sotos syndrome and to examine differences between patients with deletions or mutations of the gene encoding nuclear SET domain-containing protein 1 (NSD1; the major cause of the syndrome) and those without such alterations. Twenty-nine participants (21 males, 8 females) clinically suspected of Sotos syndrome (mean age 11y 10mo [SD 10y 11mo], range 1y 10mo-48y 5mo) were divided into an NSD1 mutation group (n=12; 8 males, 4 females) and an NSD1 non-mutation group (n=17; 13 males, 4 females). Intelligence, behaviour problems, attention-deficit-hyperactivity disorder (ADHD) symptoms, temperament, adaptive behaviour, and motor functioning were assessed with an extensive test battery. Scores were compared with those of control groups, and scores of the two subgroups were compared with each other. The mean IQ in the 21 individuals tested was 76 (SD 16; range 47-105). High rates of behaviour problems were found and patients lagged 1y 7mo to 2y 7mo behind in aspects of adaptive behaviour. In comparison with a control group of patients with a learning disability, motor functioning was better. NSD1 mutation compared with NSD1 non-mutation patients showed easier temperament, and fewer NSD1 mutation patients scored in the clinical range for 'total behaviour problems' (3/11 vs 13/17), 'internalizing behaviour' (2/11 vs 11/17), and ADHD (0/9 vs 4/15).

Preterm birth and later insulin resistance: effects of birth weight and postnatal growth in a population based longitudinal study from birth into adult life

AIMS/HYPOTHESIS

An increased risk of type 2 diabetes mellitus is associated with low birthweight after full-term gestation, including amplification of this risk by weight gain during infancy and adult body composition. Premature birth is also associated with insulin resistance, but studies conducted so far have not provided follow-up into adulthood. We studied the effects of (1) lower birthweight (as standard deviation score [SDS]) and infancy weight gain on insulin resistance in 19-year-olds born before 32 weeks of gestation, and (2) the interaction between lower birthweight SDS and infancy weight gain, as well as between lower birthweight and adult body composition, on insulin resistance.

METHODS

This was a prospective follow-up study in 346 subjects from the Project on Preterm and Small-for-gestational-age infants cohort, in whom fasting glucose, insulin and C-peptide levels were measured at 19 years. Insulin resistance was calculated with homeostatic modelling (homeostatic model assessment for insulin resistance index [HOMA-IR]).

RESULTS

Birthweight SDS was unrelated to the outcomes. Rapid infancy weight gain until 3 months post-term was weakly associated with higher insulin level (p=0.05). Adult fatness was positively associated with insulin and C-peptide levels and HOMA-IR (all p<0.001). On these parameters, there was a statistical interaction between birthweight SDS and adult fat mass (p=0.002 to 0.03).

CONCLUSIONS/INTERPRETATION

In subjects born very preterm, rapid infancy weight gain until 3 months predicted higher insulin levels at 19 years, but the association was weak. Adult obesity strongly predicted higher insulin and C-peptide levels as well as HOMA-IR. The effect of adult fat mass on these parameters was dependent on its interaction with birthweight SDS.

Could cortisol explain the association between birth weight and cardiovascular disease in later life? A meta-analysis

OBJECTIVE

Studies about the association between birth weight and circulating cortisol level have been published from 1998 onwards. However, their findings were inconsistent. To quantitatively assess the overall association between birth weight and circulating cortisol level, we aimed to perform a meta-analysis of the published literature.

METHODS

A literature search was conducted in PubMed, and selected papers were systematically reviewed. A pooled regression coefficient was calculated for the entire group as well as for males and females separately.

RESULTS

Data from 11 study populations were pooled (n = 2301). These populations differed with respect to geographical area, age, sex distribution, inclusion criteria and gestational age. We found a statistically significant inverse association between birth weight and circulating cortisol level: a 1 kg lower birth weight was associated with a 25.3 nmol/l (95% confidence interval (CI): 5.9-44.8) higher cortisol level. Separate results were reported for males and females in six study populations. The association in males was 20.6 nmol/l per kg (95% CI: 4.2-37.0) and in females it was 30.9 nmol/l per kg (95% CI: 7.4-54.4).

CONCLUSION

Differences between study populations hampered the comparability of the included studies. Although the majority of studies were underpowered, by using a meta-analytic approach we found an inverse association between birth weight and circulating cortisol level. Thus, our findings suggest that there is some evidence for a possible role of the hypothalamus-pituitary-adrenal axis in the epidemiological association between birth weight and cardiovascular disease. However, the strength of the overall association between birth weight and circulating cortisol level was weak.

Growth-reductive therapy in children with marfan syndrome

OBJECTIVES

To determine the accuracy and precision of 2 height-prediction methods in Marfan syndrome and to assess the growth-reductive effect and side effects of sex hormone treatment.

STUDY DESIGN

In a retrospective study in 31 untreated (17 boys) and 43 treated patients (21 boys) with Marfan syndrome, we assessed bone age and predicted adult height by 2 methods. The accuracy of the methods was assessed in the untreated group. The effect of therapy was corrected for outcome in the untreated group and other confounding variables with multivariate analysis.

RESULTS

Accuracy strongly varied with sex, chronological age, and prediction method. Overall precision was low. Treatment was started at a mean age of 12.8 +/- 1.4 years (boys) and 11.4 +/- 1.2 years (girls). With multiple regression analysis, a statistically significant effect was observed only in boys using a pharmacologic dosage (5.5 cm, 95% CI 0.96-10.1 cm; P = .02). Side effects were worsening of acne and weight and muscle gain.

CONCLUSIONS

In adolescents with Marfan syndrome, the accuracy and precision of 2 height-prediction methods were limited. The apparent growth-reductive effect of sex hormone treatment appears similar to earlier reports on adolescents with constitutional tall stature. There were no clinically important short-term side effects.

Growth monitoring and diagnostic work-up of short stature: an international inventorization

BACKGROUND/AIMS

Growth monitoring is almost universally performed, but few data are available on which referral criteria and diagnostic work-up are used worldwide for children with short stature.

METHODS

A short questionnaire, containing questions on auxological screening and on diagnostic criteria for short stature, was sent to all members of the European Society of Paediatric Endocrinology (ESPE) and to several pediatric endocrinologists outside Europe.

RESULTS

Responses were received from 36 countries. In 27 (75%) a child health care program existed and in 14 (39%) there was a protocol for referral of children with growth retardation. Height for age was mostly used as a referral criterion. Sixteen countries (45%) reported having a guideline in secondary health care for diagnostic work-up. Although all countries agreed on having biochemical, radiological and/or genetic tests in the diagnostic work-up, there was a wide variety of recommended tests.

CONCLUSIONS

There is little consensus on referral criteria and diagnostic work-up of children with short stature among industrialized countries. There is a need to establish evidence-based guidelines.

Genetic analysis of tall stature

Tall stature is less often experienced as an important problem than short stature. However, a correct diagnosis may be of eminent importance, especially when interventions are planned, or to know the natural history. Overgrowth can be caused by endocrine disorders and skeletal dysplasias, but also by several genetic syndromes. Despite a systematic diagnostic approach, there will be patients with tall stature who do not fit a known diagnosis. In this group of patients possibilities of genetic analysis do exist, but are not common practice. The FMR1 gene should be analyzed in patients with tall stature and mental retardation, and in these patients the NSD1 gene can be considered whenever some features of Sotos syndrome do exist. In tall patients without mental retardation and some features of Sotos or Beckwith-Wiedemann syndrome it may still be useful to look for mutations in the NSD1 gene, but also for changes in the 11p15 region. The various possibilities are discussed and placed in a flowchart.

Nationwide age references for sitting height, leg length, and sitting height/height ratio, and their diagnostic value for disproportionate growth disorders

AIMS

To obtain age references for sitting height (SH), leg length (LL), and SH/H ratio in the Netherlands; to evaluate how SH standard deviation score (SDS), LL SDS, SH/H SDS, and SH/LL SDS are related to height SDS; and to study the usefulness of height corrected SH/H cut-off lines to detect Marfan syndrome and hypochondroplasia.

METHODS

Cross-sectional data on height and sitting height were collected from 14,500 children of Dutch origin in the age range 0-21 years. Reference SD charts were constructed by the LMS method. Correlations were analysed in three age groups. SH/H data from patients with Marfan syndrome and genetically confirmed hypochondroplasia were compared with height corrected SH/H references.

RESULTS

A positive association was observed between H SDS, SH SDS, and LL SDS in all age groups. There was a negative correlation between SH/H SDS and height SDS. In short children with a height SDS <-2 SDS, a cut-off limit of +2.5 SD leads to a more acceptable percentage of false positive results. In exceptionally tall children, a cut-off limit of -2.2 SDS can be used. Alternatively, a nomogram of SH/H SDS versus H SDS can be helpful. The sensitivity of the height corrected cut-off lines for hypochondroplasia was 80% and for Marfan syndrome only 30%.

CONCLUSIONS

In exceptionally short or tall children, the dependency of the SH/H ratio (SDS) on height SDS has to be taken into consideration in the evaluation of body proportions. The sensitivity of the cut-off lines for hypochondroplasia is fair.

Monozygous triplets discordant for transient neonatal diabetes mellitus and for imprinting of the TNDM differentially methylated region

Transient neonatal diabetes mellitus (TNDM) is associated with paternal over-expression of an imprinted locus on chromosome 6q24, which contains one differentially methylated region (DMR); maternal demethylation at the DMR accounts for approximately 20% of cases. Here we report female monozygous triplets, two of whom have TNDM arising from loss of maternal methylation within the TNDM DMR.

[Primary adrenal insufficiency in children]

Three boys, aged 5, 11 and 14 years, were admitted due to vomiting, fatigue and dehydration, and a 10-year-old boy was admitted due to circulatory and respiratory insufficiency. Two had Addison's disease, one had a late presentation of congenital adrenal hypoplasia due to a DAX-1 mutation and in one adrenal insufficiency was the first manifestation ofadrenoleukodystrophia. The boys recovered after treatment. It is important to recognise the symptoms of adrenal insufficiency, because treatment can be life-saving. After the initial diagnosis the underlying pathology should be sought.

Homozygous and heterozygous expression of a novel insulin-like growth factor-I mutation

IGF-I is a key factor in intrauterine development and postnatal growth and metabolism. The secretion of IGF-I in utero is not dependent on GH, whereas in childhood and adult life, IGF-I secretion seems to be mainly controlled by GH, as revealed from studies on patients with GHRH receptor and GH receptor mutations. In a 55-yr-old male, the first child of consanguineous parents, presenting with severe intrauterine and postnatal growth retardation, microcephaly, and sensorineural deafness, we found a homozygous G to A nucleotide substitution in the IGF-I gene changing valine 44 into methione. The inactivating nature of the mutation was proven by functional analysis demonstrating a 90-fold reduced affinity of recombinantly produced for the IGF-I receptor. Additional investigations revealed osteoporosis, a partial gonadal dysfunction, and a relatively well-preserved cardiac function. Nine of the 24 relatives studied carried the mutation. They had a significantly lower birth weight, final height, and head circumference than noncarriers. In conclusion, the phenotype of our patient consists of severe intrauterine growth retardation, deafness, and mental retardation, reflecting the GH-independent secretion of IGF-I in utero. The postnatal growth pattern, similar to growth of untreated GH-deficient or GH-insensitive children, is in agreement with the hypothesis that IGF-I secretion in childhood is mainly GH dependent. Remarkably, IGF-I deficiency is relatively well tolerated during the subsequent four decades of adulthood. IGF-I haploinsufficiency results in subtle inhibition of intrauterine and postnatal growth.

[Measuring the length of newborn infants]

Since 1985, measurement of the length of neonates has been practically abandoned in the Netherlands because it was thought that stretching the legs and knees briefly in order to measure the length immediately after birth could be harmful for the development of the hip joint. However, this fear seems unjustified. Measuring the length of the neonate provides useful information regarding the general condition and has predictive value for the final adult height. If an infant is disproportionately small in comparison with its weight or small for its gestational age with insufficient catch-up growth, this may be an indication of underlying pathology. As a rule, the length of all neonates should be measured immediately after birth and length measurement should be re-introduced as part of standard care. Length measurement can be done with sufficient accuracy after proper instruction. For babies born after incomplete breech presentation, length measurement should be postponed for about a week.

Clinicians' perspective on quality of life assessment in paediatric clinical practice

AIM

This study was undertaken to investigate paediatric clinicians' views on and use of quality of life (QoL) assessment in clinical practice.

METHODS

A survey was conducted among members of the Dutch Paediatric Association via e-mail.

RESULTS

Over half of the 303 respondents (57%) believed that it was possible to use QoL questionnaires in clinical practice. The majority indicated that assessing QoL was beneficial and that it was especially necessary to assess QoL in children with a chronic disease (82%). Although only a minority (17%) currently used QoL questionnaires, most respondents would want to use QoL questionnaires in the future (76%). Obstacles that prevent the use of QoL questionnaires are the extra time needed for assessment, the unavailability of standardized questionnaires and insufficient knowledge about QoL.

CONCLUSION

This survey shows that paediatric clinicians are positive towards QoL assessment, but that certain obstacles prevent the use of questionnaires. Thus, to facilitate future use, QoL questionnaires need to be developed from the perspective of the paediatrician. This means that they need to be developed for clinical use and brought to the attention of the paediatric health care community, demonstrating their validity to child health care.

Mutations in the NSD1 gene in patients with Sotos syndrome associate with endocrine and paracrine alterations in the IGF system

OBJECTIVE

To investigate the effect of nuclear receptor Su-var, 3-9, enhancer of zeste, trithorax (SET) domain-containing protein 1 (NSD1) gene alteration in patients with Sotos syndrome on plasma IGFs and IGF-binding proteins (IGFBPs), as well as on the IGF/IGFBP system activity at the tissue level.

DESIGN

Twenty-nine patients suspected of Sotos syndrome were divided into two groups: patients with heterozygous deletions or mutations in the NSD1 gene (NSD1(+/-)) (n=11) and subjects without (NSD1(+/+)) (n=18). Plasma samples (n=29) and skin fibroblasts (n=23) were obtained. The results of both groups were compared and related to reference values.

METHODS

IGF-I, IGF-II, IGFBP-2, IGFBP-3, IGFBP-4 and IGFBP-6 levels were determined by RIAs. The mitogenic response of fibroblasts to IGFs was investigated by [methyl-(3)H]thymidine incorporation. IGFBP-3 levels in the culture media were measured by RIA. IGFBP-3 mRNA expression was determined by real time RT-PCR.

RESULTS

NSD1(+/-) patients showed significantly altered levels of IGF-I (mean-1.2 SDS), IGF-II (-1.2), IGFBP-3 (-1.7), IGFBP-4 (-0.4), IGFBP-2 (+0.8) and IGFBP-6 (+1.5). The NSD1(+/+) patients did not differ from the reference, with the exception of the mean IGFBP-3 level (-1.3). Basal proliferation and mitogenic response to IGFs was diminished in NSD1(+/-) fibroblasts compared with NSD1(+/+) (basal, P=0.02; IGF-I, P<0.001; IGF-II, P=0.02). Compared with control fibroblasts, only the mitogenic response was diminished (basal, P=0.07; IGF-I, P=0.04; IGF-II, P=0.04). A trend of higher IGFBP-3 secretion after IGF-I stimulation (P=0.09) and 3.5-5 times higher mRNA expression of IGFBP-3 in basal conditions was found in NSD1(+/-) fibroblasts in comparison to controls.

CONCLUSIONS

NSD1(+/-) patients show endocrine and paracrine changes in the IGF system. These changes may contribute to the abnormal growth pattern.

Benefit of postponing normal puberty for improving final height

Experiments of nature and clinical observations have provided indications that postponing puberty may increase final height in short children. In children with central precocious puberty, a GnRH analog (GnRHa) alone is efficacious in increasing final height, but in other conditions a combination of growth hormone (GH) and GnRHa is needed. In GH-deficient children with early onset of puberty and poor height prediction, the combination of GH and GnRHa increases final height by 1.0-1.3 s.d. In children with idiopathic short stature and persistent short stature after intrauterine growth retardation, the combination also appears to be beneficial. Potential side effects include weight gain, a negative effect on bone mineralization, and psychosocial consequences. More data on long-term safety have to be collected before the combination of GH and GnRHa in children with idiopathic short stature should be considered for clinical use outside clinical trials.

[Clinical characteristics and management of adolescents admitted to the emergency ward for alcohol intoxication in the region of The Hague during the period 1999-2001]

OBJECTIVE

To analyse the findings in adolescents between the ages of 12 and 17 who were admitted to the emergency ward as a result of excessive alcohol consumption.

DESIGN

Retrospective.

METHOD

The clinical characteristics, laboratory findings and treatment policy were studied in adolescents between the ages of 12 and 17 who were admitted for alcohol intoxication (> or = 1/1000) to the emergency wards of Leiden University Medical Centre, Juliana Children's Hospital, Haaglanden Medical Centre (Westeinde location) or the Leyenburg Hospital (all hospitals in the area of The Hague, The Netherlands) during the period 1999-2001.

RESULTS

In the three successive years, the number of patients was 19, 18 and 51, respectively; there were a total of 58 boys and 30 girls. Laboratory determinations and other investigations were carried out and/or recorded in varying numbers of patients. The cause of the intoxication was usually the consumption of spirits together with friends; 60% of the patients had a Glasgow coma score < 15 and 30% were admitted to hospital. In 25% the visit to the emergency ward was preceded by an accident in which alcohol played a part. Little attention seems to have been paid to aftercare in the form of a follow-up visit.

Height, weight, body mass index and pubertal development references for children of Moroccan origin in The Netherlands

AIM

To provide growth and sexual maturation reference data for Moroccan children living in The Netherlands and to compare them with the reference data of children of Dutch origin.

METHODS

Cross-sectional growth and demographic data were collected from 2880 children of Moroccan origin and 14,500 children of Dutch origin living in The Netherlands in the age range 0-20 y. Growth references for length, height, weight, weight-for-height, body mass index (BMI) and head circumference were constructed with the LMS method. Predictive variables for height and BMI were assessed by regression analyses. Reference curves for sexual maturation were estimated by a generalized additive model.

RESULTS

Moroccan young adults were on average 9 cm shorter than their Dutch contemporaries. Mean final height was 174.7 cm for males and 161.3 cm for females. Height differences in comparison with Dutch children increase from 2 y onwards. Height SDS was predominantly associated with target height. Compared to Dutch children, maturation started 0.2 and 0.9 y later for girls and boys, respectively. Median age at menarche was 12.9 y, 3.6 mo earlier than in Dutch girls (p = 0.001). BMI of Moroccan children was above that of Dutch children, especially for girls. BMI SDS was associated with birthweight in the age group 0 - < or = 5 y.

CONCLUSION

Moroccan children living in The Netherlands are substantially shorter than Dutch children. Girls have higher weight-for-height and BMI for age. Median age at menarche occurs earlier. Given these differences, separate growth charts for the Moroccan children are useful.

Towards evidence based referral criteria for growth monitoring

AIMS

To evaluate the performance of growth monitoring in detecting diseases. Turner's syndrome (TS) is taken as the target disease.

METHODS

Case-control simulation study. Three archetypal screening rules are applied to longitudinal growth data comparing a group with TS versus a reference group from birth to the age of 10 years. Main outcome measures were sensitivity, specificity, and median referral age.

RESULTS

Clear differences in performance of the rules were found. The best rule takes parental height into account. Combining rules could improve diagnostic accuracy.

CONCLUSION

Growth monitoring is useful to screen for TS. A combined rule that takes absolute height SDS, parental height, and deflection in height velocity into account is the best way to do this. Similar research is needed for other diseases, populations, and ages, and the results should be synthesised into evidence based referral criteria.

Many referrals under Dutch short stature guidelines

The number of referrals under strict adherence to the Dutch consensus guidelines for short stature was estimated using longitudinal data from 970 children (0-10 years). Results showed that over 38% of all children would have to be referred one or more times. There is therefore a clear need to revise the current guidelines.

Plasma insulin-like growth factors (IGFs), IGF-Binding proteins (IGFBPs), acid-labile subunit (ALS) and IGFBP-3 proteolysis in individuals with clinical characteristics of Sotos syndrome

OBJECTIVE

Sotos syndrome is an overgrowth syndrome of poorly understood aetiology. We investigated whether this syndrome is related to alterations in plasma insulin-like growth factors (IGFs), IGF-binding proteins (IGFBPs), acid-labile subunit (ALS) and serum IGFBP-3 proteolysis.

DESIGN

Based on clinical criteria, 32 patients with clinical characteristics of Sotos syndrome (median age 8.4 years, range 1.8-48.4) were categorised into three groups: typical (n = 10, group 1), dubious (n = 12, group 2) and atypical (n = 10, group 3). Blood samples were obtained from 29 patients.

MEASUREMENTS

Plasma IGF-I, IGF-II, E-II (pro-IGF-II and E-domain fragments), IGFBP-2, IGFBP-3, IGFBP-4, IGFBP-6 and ALS were measured by specific radioimmunoassays (RIAs). Except for E-II immunoreactivity, the concentrations were compared with those of age references, and expressed as standard deviation scores (SDS). IGFBP-3 proteolysis was assessed by incubation of serum with [125I]-IGFBP-3, followed by gel electrophoresis and was then compared with that in normal serum and third trimester pregnancy serum.

RESULTS

Patients in group 1 showed significantly reduced plasma levels of IGF-II (median -0.9 SDS; p = 0.01), IGFBP-4 (-0.5 SDS; p = 0.02) and IGFBP-3 (-1.0 SDS; p = 0.01). Mean IGFBP-3 proteolysis was higher than in normal standard serum (61% vs 37%; p < 0.01) but lower than in third trimester pregnancy serum (94%; p < 0.01). Plasma IGF-I showed a tendency towards low values (median -0.9 SDS; p = 0.09), IGFBP-6 and ALS a tendency towards elevated levels (median values +0.8 SDS; p = 0.07 and +2.3 SDS; p = 0.09), and IGFBP-2 was normal. The mean value of E-II immunoreactivity was 8.7 nmol/l, similar to that in pooled normal plasma (8.6 nmol/l). Plasma and serum parameters in groups 2 and 3 were similar to reference values with the exception of plasma IGFBP-3 (in groups 2 and 3 median < or = -1.1 SDS; p < or = 0.02) and ALS (in group 3 median +1.3 SDS; p < 0.01).

CONCLUSIONS

Patients with typical Sotos syndrome show low plasma IGF-II, IGFBP-3, IGFBP-4, and increased proteolysis of IGFBP-3 in serum. The extent to which these findings are associated with the pathophysiology of Sotos syndrome remains uncertain.

Disturbances of growth and endocrine function after busulphan-based conditioning for haematopoietic stem cell transplantation during infancy and childhood

It is generally assumed that busulphan/cyclophoshamide (Bu/Cy)-based conditioning regimens for haematopoietic stem cell transplantation (SCT) do not affect growth. We evaluated growth and endocrine function after Bu/Cy-based conditioning in 64 children without a history of irradiation. Mean height standard deviation scores remained stable, but unexplained disturbances of growth after SCT were found in 17/48 (35%) of the children without growth-limiting disorders (10/23 in patients treated for haematological malignancies). In 10 patients, growth hormone (GH) secretion status was evaluated, and insufficient GH secretion was diagnosed in four patients. Thyroid function was evaluable in 52 patients. Two developed antibody-mediated thyroid disorders and 10 (19%) compensated primary hypothyroidism. Gonadal function was evaluable in 21 patients and was normal in all seven patients treated with low-dose Bu (8 mg/kg), whereas seven of the 14 children receiving high-dose Bu (16-20 mg/kg) developed gonadal failure; the majority of these patients had not been exposed to gonadotoxic therapy prior to Bu/Cy. Of the 49 evaluable patients, 16 developed subclinical hyperparathyroidism. We conclude that, besides gonadal and thyroid dysfunction, impaired growth and hyperparathyroidism often occur after Bu/Cy conditioning for SCT and that growth impairment may be the result of insufficient GH secretion.

Expression of estrogen receptors and enzymes involved in sex steroid metabolism in the rat tibia during sexual maturation

Estrogens are essential for bone mass accrual but their role before sexual maturation has remained elusive. Using in situ hybridization and immunohistochemistry, we investigated the expression of both estrogen receptor (ER) alpha and beta mRNA and protein as well as several mRNAs coding for enzymes involved in sex steroid metabolism (aromatase, type I and II 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD), steroid sulfatase (STS) and type I 5 alpha-reductase) on sections of tibial metaphyses before (1- and 4-week-old), during (7-week-old) and after (16-week-old) sexual maturation in female and male rats. ER alpha and ER beta mRNA and protein were detected in metaphyseal bone in lining cells, osteoblasts, osteoclasts and some osteocytes with no apparent differences in expression during development or between the sexes. In contrast, aromatase, type I and II 17 beta-HSD and type I 5 alpha-reductase mRNAs were first detected in osteoblasts, osteoclasts and occasionally in osteocytes from sexual maturation (7-week-old rat) and onwards. Only STS was present before sexual maturation. To study the significance of ER alpha and beta expression in bone before sexual maturation when circulating sex steroid levels are low, 26-day-old female and male rats underwent gonadectomy or 17 beta-estradiol (E(2)) supplementation (0.5 mg/21 days) during 3 weeks. Following gonadectomy, trabecular bone volume (TBV) was lower in males (P=0.03) and there was a trend towards reduction in females (P=0.057). E(2) supplementation increased tibial TBV compared with controls in both genders as assessed by Masson-Goldner staining. These data suggest that the presence of ERs in bone cells before sex maturation might be of significance for bone mass accrual. Furthermore, based on the mRNA expression of the crucial enzymes aromatase and type I 17 beta-HSD, we suggest that bone cells in the tibial metaphysis acquire the intrinsic capacity to metabolize sex steroids from sexual maturation onwards. This process may contribute to the beneficial effects of estrogen on bone mass accrual, possibly by intracrinology.

Is hypotension a major risk factor for neurological morbidity at term age in very preterm infants?

OBJECTIVE

To investigate the influence of perinatal risk factors, especially hypotension, on neuromotor status at term in surviving preterm infants born before 32 weeks of gestation.

METHODS

This study is part of the Leiden Follow-Up Project on Prematurity: a prospective, regional study of 266 live born infants with a gestational age (GA) < 32 weeks born in 1996-1997. Twenty-eight infants died before term age. Two hundred and eleven infants were examined neurologically at term according to Prechtl. The findings were classified as normal (N), mildly abnormal (MA) or definitely abnormal (DA). Hypotension was defined as a mean arterial blood pressure (MABP) < 30 mm Hg on at least two occasions.

RESULTS

One hundred and six (50%) infants were classified as neurologically N, 92 (44%) infants were classified as MA and 13 (6%) infants as DA. Hypotension, bronchopulmonary dysplasia (BPD), flaring and cystic periventricular leucomalacia (PVL) were risk factors for neurological morbidity. Of the 68 infants with hypotension, 33 (49%) were classified as MA and 7 (10%) as DA. Of the 141 infants without hypotension, 58 (41%) were MA, and 5 (4%) were DA. The odds ratio of hypotension for neurological morbidity was 1.9 (95% CI 1.06-3.40), adjusted for gestational age, birth weight, small for gestational age (SGA) and gender, it was 1.96 (95% CI 1.02-3.77). The adjusted odds ratio of PVL was 18.6 (4.4-78.5), of flaring was 2.37 (1.18-4.74) and of BPD was 2.44 (1.08-5.5).

CONCLUSIONS

Apart from gestational age, periventricular leucomalacia, and bronchopulmonary dysplasia, hypotension in preterm infants is a major risk factor for neurological morbidity at term.

Quality of life in adults following bone marrow transplantation during childhood

SUMMARY

Quality of life (QOL) was assessed in 22 young adults, 14 years - on average- after having received bone marrow transplantation (BMT) during childhood at the Leiden University Medical Center. All were disease-free and >16 years when interviewed. The sickness impact profile and the Medical Outcome Study 36-item Short Form Health Survey were used as generic questionnaires in the assessment of QOL. The Functional Assessment of Cancer Therapy-Bone Marrow Transplant Scale (FACT-BMT) was used as a disease-specific measure of QOL. Coping was assessed by means of the Utrecht coping list. BMT-related variables were obtained from medical files. Of the generic QOL measures, most results fell within the normal range of functioning, although some illness-related impairment was reported on subscales for general and work-related functioning. Compared to a reference sample of patients who had received BMT as adults, patients involved in this study scored significantly higher on the 'emotional well-being' subscale of the FACT-BMT, indicating significantly better emotional functioning. The age at BMT and total body irradiation (TBI) were not related to patients' QOL. We can conclude that at long term, having received BMT during childhood does not negatively affect the QOL of patients. Bone Marrow Transplantation (2004) 33, 329-336. doi:10.1038/sj.bmt.1704345 Published online 1 December 2003

Systemic and local regulation of the growth plate

The growth plate is the final target organ for longitudinal growth and results from chondrocyte proliferation and differentiation. During the first year of life, longitudinal growth rates are high, followed by a decade of modest longitudinal growth. The age at onset of puberty and the growth rate during the pubertal growth spurt (which occurs under the influence of estrogens and GH) contribute to sex difference in final height between boys and girls. At the end of puberty, growth plates fuse, thereby ceasing longitudinal growth. It has been recognized that receptors for many hormones such as estrogen, GH, and glucocorticoids are present in or on growth plate chondrocytes, suggesting that these hormones may influence processes in the growth plate directly. Moreover, many growth factors, i.e., IGF-I, Indian hedgehog, PTHrP, fibroblast growth factors, bone morphogenetic proteins, and vascular endothelial growth factor, are now considered as crucial regulators of chondrocyte proliferation and differentiation. In this review, we present an update on the present perception of growth plate function and the regulation of chondrocyte proliferation and differentiation by systemic and local regulators of which most are now related to human growth disorders.

A novel nonsense mutation in the Cyp11B1 gene from a subject with the steroid 11beta-hydroxylase form of congenital adrenal hyperplasia

11beta-Hydroxylase deficiency (11beta-OHD) inherited in an autosomal recessive manner accounts for about 5-8% of congenital adrenal hyperplasia (CAH). In order to clarify the underlying mechanism causing 11beta-OHD, we have done the molecular genetic analysis on the CYP11B1 gene in a patient diagnosed as 11beta-OHD. The nucleotide sequence of the patient's CYP11B1 revealed a novel nonsense mutation that converts codon 265 CAG (glutamine) to TAG (stop) of exon 4. Restriction fragment length polymorphism (RFLP) data showed that the patient was homozygous for the mutation. The above results confirm that the patient suffers from complete loss of the final step in cortisol biosynthesis pathway because of the nonsense mutation.

Genetic Analysis of Short Stature

Short stature is a major concern for patients and their parents, and represents a diagnostic challenge to the clinician. A correct diagnosis is of particular importance in view of the availability of effective, but costly, therapy in a small subset of cases. Many different genetic etiologies of short stature are known. Therefore, chromosome as well as molecular analysis are requisite diagnostic investigations in children with short stature. Particularly in the group of children with idiopathic short stature, possibilities of molecular analysis are often underestimated. Important options are UPD7 and the FGFR3, SHOX, GH1 and GHR genes. Furthermore, analysis of the IGF and IGF1R genes should be considered. We propose a flow chart for molecular analysis in short stature.

Adult height corrected for shrinking and secular trend

BACKGROUND

If in growth studies on adults of different ages and generations height standard deviation scores (SDS) is to be calculated, individual heights should be compared with the average height for that generation (corrected for secular trend) at that age (corrected for shrinking).

AIM

To generate mathematical formulas for calculating adult height SDS corrected for shrinking and secular trend.

SUBJECTS AND METHODS

Decline of height by age was modelled based on data derived from the Baltimore Longitudinal Study of Aging. Based on mean height of Dutch conscripts in 1917 and data from four consecutive nationwide growth studies (1955, 1965, 1980 and 1997), and assuming a constant male-female difference of 13 cm, the secular trend was modelled over 80 years. The average coefficient of variation was calculated from the last three Dutch nationwide growth studies.

RESULTS

Height at 21 years of age can be estimated as current height t 0.042*(age - 21) -0.0015*(age - 21)2 for males, and current height + 0.039*(age - 21) + 0.0019*(age - 21)2 for females. Mean height of 21-year-olds between 1917 and 1997 is characterized by linear regression. The coefficient of variation was close to 3.8%. Adult height SDS is calculated by the equation (A - B)/(0.038B), where A is the estimated individual height at 21 years and B is the average height of 21-year-olds in that generation.

CONCLUSION

For studies on adult height at various ages and in various generations, these equations can be used to reduce experimental noise.

Effect of x-irradiation on growth and the expression of parathyroid hormone-related peptide and Indian hedgehog in the tibial growth plate of the rat

AIM

To study the effect of irradiation on the longitudinal growth and the expression of parathyroid hormone-related peptide (PTHrP) and Indian hedgehog (IHh) in tibial growth plates of rats.

METHODS

At 3 weeks of age, 30 male rats received a single fraction of irradiation (8 Gy) to their right hind limb, and small groups of animals were sacrificed 1, 2, 3, 5, 7, 10, 15, and 26 weeks after irradiation. Weight and length of both irradiated and nonirradiated tibiae were measured, and sections of the tibiae were stained with HE. PTHrP and IHh were visualized using immunohistochemical techniques.

RESULTS

Radiation resulted in persistent growth delay of the irradiated tibiae, with a difference in length of more than 10% between the irradiated and the nonirradiated tibiae 15 weeks or more after irradiation. The growth plate architecture was disturbed, and the expression of both PTHrP and IHh was decreased in the irradiated tibiae.

CONCLUSION

As PTHrP and IHh are key regulators of both the pace and the synchronization of the differentiation of growth plate chondrocytes, the reduced expression of PTHrP and IHh may contribute to the changes found after irradiation.

Behaviour at 2 years of age in very preterm infants (gestational age < 32 weeks)

AIM

The objective of this study was to determine behavioural outcome and risk factors for abnormal behaviour at 2 y corrected age in very premature infants in a regionally defined, prospective cohort study.

METHODS

The Leiden Follow-Up Project on Prematurity includes all liveborn infants of < 32 wk gestational age, born in 1996/1997 (n = 266). Behaviour was assessed with the Child Behaviour Checklist 2-3.

RESULTS

An analysis of 158 questionnaires of 206 survivors (77%) was carried out. Fourteen children (9%) had a total problem score > p90 ("clinical range"). This percentage is comparable with the 10% found in a sample of 2- to 3-y-olds from the Dutch general population. Univariate analysis showed higher syndrome scale scores in one or more of the Child Behaviour Checklist scales in children of lower gestational age, small for gestational age (birthweight < p10), with neurological abnormalities at term or at 2 y and of non-Dutch origin. Lower socioeconomic status and postnatal treatment with dexamethasone were associated with higher scores in the somatic problems scale and lower maternal age at birth with a higher total problem score. After correction for confounding variables, the associations between small for gestational age, neurological abnormalities at 2 y and the anxious/depressed and/or withdrawn scales remained significant.

CONCLUSION

The prevalence of behavioural problems at 2 y corrected age in this cohort of very premature infants (gestational age < 32 wk) was comparable with that in a general population sample. Children born small for gestational age or with neurological abnormalities at 2 y of age had higher syndrome scale scores, mainly for anxious/depressed and/or withdrawn behaviour.

Catch-up growth and endocrine changes in childhood celiac disease. Endocrine changes during catch-up growth

Childhood celiac disease may lead to a failure of statural growth. After institution of a gluten-free diet most patients exhibit catch-up growth. Catch-up growth is a remarkable phenomenon characterized by a supranormal height velocity. One of the hypothetical mechanisms of catch-up growth is that an increased activity of the somatotrophic axis is involved. In order to provide further insight in the physiology of catch-up growth, auxological and endocrine changes were prospectively studied in 28 children with newly diagnosed celiac disease. The results demonstrate a malnutrition-like state of the somatotrophic axis at the time of diagnosis and a rapid recovery of this axis towards normal functioning after institution of the gluten-free diet. Although several correlations between these endocrine alterations and auxological parameters were detected, it is questionable whether the endocrine changes are the driving force behind catch-up growth.

A 43-year-old male with untreated panhypopituitarism due to absence of the pituitary stalk: from dwarf to giant

A 43-yr-old male was referred because of an x-ray made after a fall, which showed open epiphysis of the arm. The man had always been short for his age; during childhood he once consulted a pediatrician because of short stature, but thereafter he never sought medical attention. At age 18 yr he was not allowed to join the army because of his height of 147 cm. He continued to grow steadily and finally reached 193 cm. He had no complaints and considered himself reasonably fit. Physical examination showed a disproportional man with a body mass index of 29.3 kg/m(2) and Tanner stage P1G1. Laboratory investigations showed hormone levels consistent with multiple pituitary deficiency, with dynamic tests consistent with hypothalamic or pituitary stalk disease. Magnetic resonance scanning of the brain showed a small anterior pituitary remnant, no pituitary stalk, and an ectopic neurohypophysis. This case of untreated panhypopituitarism shows a particular growth curve with an average growth velocity of 2 cm/yr, resembling patients with estrogen receptor mutation or aromatase deficiency. A literature study of other adult patients with untreated panhypopituitarism shows a variable growth pattern. Some speculations about possible reasons for this variability in clinical characteristics are presented.

Evidence for genomic and nongenomic actions of estrogen in growth plate regulation in female and male rats at the onset of sexual maturation

Recently, both estrogen receptor (ER) alpha and beta were detected in growth plate chondrocytes of rats before sexual maturation, implying a role for estrogen at this stage. In this study, therefore, we investigated the effects of ovariectomy (OVX) or estrogen supplementation on parameters of longitudinal growth in 26-day-old rats, which were sexually immature at the start of the experiment. OVX caused an increase in body weight gain, tibial length and growth plate width due to an increased proliferating zone. This increase correlated with an increase in cell number, with a decrease in cell diameter and with increased proliferating cell nuclear antigen (PCNA) immunostaining compared with sham. Interestingly, the increase in proliferation was not caused by an increase in insulin-like growth factor-I (IGF-I) mRNA expression in the growth plate as assessed by real-time PCR. In contrast to OVX, 17beta-estradiol (E(2)) supplementation (0.5 mg/21 days) of 26-day-old female rats caused a strong decrease in body weight gain, tibial length and growth plate width. The latter was explained by a reduction of the proliferating zone width, which correlated with a reduced number of PCNA-positive cells (not significant) and by a reduction of the hypertrophic zone width. In male rats supplemented with E(2), similar effects were observed compared with the females. ERalpha and beta immunostaining was found predominantly in late proliferating and early hypertrophic chondrocytes. OVX did not affect ER expression but E(2) supplementation strongly decreased immunostaining for both ERalpha and beta in both sexes. Besides E(2), desoxyestrone (DE), an activator of nongenomic estrogen-like signaling (ANGEL) and 2-methoxyestradiol (2-MeO-E(2)), a tissue-selective naturally occurring metabolite of E(2), were administered to female and male rats of the same age. Compared with E(2), these compounds had less pronounced, though significant, effects on some parameters of longitudinal growth in both sexes, especially on growth plate characteristics. In conclusion, E(2) may exert effects on longitudinal growth before and at the onset of sexual maturation, despite very low endogenous serum levels at these stages. There may be a role for nongenomic signaling in body weight gain, tibial length and growth plate width but genomic signaling prevails.

Sex steroid metabolism in the tibial growth plate of the rat

To assess whether growth plate-specific production of sex steroids is possible, we have surveyed the presence of several key-enzymes involved in androgen and estrogen metabolism in the tibial growth plate of female and male rats during development. Using in situ hybridization, mRNAs of aromatase p450, type I and II 17beta-hydroxysteroid dehydrogenase (HSD), steroid sulfatase (STS), and 5alpha-reductase were detected in proliferating and hypertrophic chondrocytes of the growth plate. The former three were strongly up-regulated around sexual maturation (7 wk), whereas the latter two were expressed at a relatively constant level during development. These data were supported by measuring aromatase, type I 17beta-HSD, and STS enzyme activities in chondrocytes collected from tibial growth plates at 1 and 7 wk of age. Of the enzymes studied, there were minor differences between the sexes in aromatase and 5alpha-reductase expression only. In conclusion, our findings clearly indicate the presence of various enzymes involved in sex steroid metabolism in the tibial growth plate, especially in sexually maturing rats, a timepoint at which sex steroids have major effects on longitudinal growth. Our data suggest that intracrinology in the rat growth plate can occur and may be a major source of local sex steroid delivery.

Growth hormone therapy

Since 1958 growth hormone (GH) has been used as substitution treatment for children with GH deficiency. At present, it is clear that a dose of 0.23 mg/kg/week can lead to a final height close to target height, but in view of the wide inter-individual variation, alternative regimens based on invidualizing the dosage with the help of prediction models are being investigated. The best strategy during puberty (increase the dosage, delay puberty) is still uncertain. The value of GH in idiopathic short stature is still heavily debated, although the average final height gain on 0.33 mg/kg/week is 5-7 cm. GH is efficacious in short stature due to chronic renal failure and Prader-Willi syndrome. In other conditions insufficient data are available. There are few side-effects.

Biochemical markers of growth hormone (GH) sensitivity in children with idiopathic short stature: individual capacity of IGF-I generation after high-dose GH treatment determines the growth response to GH

OBJECTIVE AND PATIENTS

To assess multiple dose-response relationships between three GH doses (1.5, 3.0 and 6.0 IU/m2) and nine different biochemical markers of GH sensitivity in a well-defined group of 17 children with idiopathic short stature (ISS).

DESIGN AND MEASUREMENTS

Serum levels of IGF-I, IGF-II and IGFBP-3, and peripheral markers leptin, C-terminal propeptide of type I collagen (PICP) and N-terminal propeptide of type III collagen (PIIINP), alkaline phosphatase (AP) and osteocalcin (OC) were measured at the start and after 2 and 12 weeks of periods of no treatment, GH 1.5 IU/m2 and GH 3.0 IU/m2. Twelve-week washout periods were applied between the 12-week GH-treatment periods. High-dose GH treatment was given during the second year of study and all serum markers were measured at start, after 2 and 12 weeks and 1 year of GH 6.0 IU/m2. In 18 non-GH-treated children with ISS the same parameters were measured yearly. The bone resorption marker urinary deoxypyridinoline (DPD) was measured during 12-h day and night periods at start and after 2 weeks GH 1.5, 3.0 and 6.0 IU/m2.

RESULTS

All markers were GH dependent, but the timing of maximal response varied among different markers. Height SDS at start, age at start and IGF-II at baseline were inversely related to the first-year growth response (r = -0.73, P = 0.001; r = -0.53, P = 0.03; and r = -0.53, P = 0.03, respectively). Some statistically significant correlations between biochemical responses on low GH doses (1.5 or 3.0 IU/m2) and second-year growth response were found, but these showed no consistent pattern. However, all changes in IGF-I SDS after GH 6.0 IU/m2 measured either after 2 or 12 weeks or 1 year correlated significantly with the second-year growth response (r = 0.55, P = 0.02; r = 0.81, P = 0.001; and r = 0.86, P < 0.001, respectively). Baseline or GH-stimulated levels of peripheral markers did not correlate with the growth response.

CONCLUSION

The individual capacity of IGF-I generation after high-dose GH treatment (6.0 IU/m2) determines the growth response on high-dose GH treatment. Peripheral markers do not seem to play a role in growth prediction of children with ISS.

High dose growth hormone treatment induces acceleration of skeletal maturation and an earlier onset of puberty in children with idiopathic short stature

BACKGROUND

Long term growth hormone (GH) treatment in children with idiopathic short stature (ISS) results in a relatively small mean gain in final height of 3-9 cm, which may not justify the cost of treatment. As it is unknown whether GH treatment during puberty adds to final height gain, we sought to improve the cost-benefit ratio, employing a study design with high dose GH treatment restricted to the prepubertal period.

AIMS

To assess the effect of short term, high dose GH treatment before puberty on growth, bone maturation, and pubertal onset.

METHODS

Five year results of a randomised controlled study are reported. Twenty six boys and nine girls were randomly assigned to a GH treatment group (n = 17) or a control group (n = 18). Inclusion criteria were: no signs of puberty, height less than -2 SDS, age 4-8 years for girls or 4-10 years for boys, GH concentration >10 micro g/l after provocation, and normal body proportions. To assess GH responsiveness, children assigned to the GH treatment group received GH treatment for two periods of three months (1.5 IU/m2/day and 3.0 IU/m2/day), separated by three month washout periods, during the first year of study. High dose GH treatment (6.0 IU/m2/day) was then started and continued for at least two full years. When puberty occurred, GH treatment was discontinued at the end of a complete year's treatment (for example, three or four years of GH treatment).

RESULTS

In response to at least two years on high dose GH treatment, mean (SD) height SDS for chronological age increased significantly in GH treated children from -2.6 (0.5) to -1.3 (0.5) after two years and -1.4 (0.5) SDS after five years of study. No changes in height SDS were observed in controls. A rapid rate of bone maturation of 3.6 years/2 years in treated children compared to 2 years/2 years in controls was observed in response to two years high dose GH treatment. Height SDS for bone age was not significantly different between groups during the study period. GH treated children entered into puberty at a significantly earlier age compared to controls.

CONCLUSIONS

High dose GH treatment before puberty accelerates bone age and induces an earlier onset of puberty. This may limit the potential therapeutic benefit of this regimen in ISS.

[Osteomyelitis in children: sometimes hard to recognize]

In a 15-year-old girl with pain in the right lower abdomen and a 9-year-old boy with pain in the left thigh, an elevated sedimentation rate and C-reactive protein were reason to suspect osteomyelitis. Although no abnormalities could be seen on X-rays, skeletal scintigraphy revealed pathology in Liv-v and the sacroiliac joint, respectively. In the girl, Staphylococcus aureus was cultivated from material obtained by puncture and biopsy. After treatment with antibiotics, rest and gradual mobilisation, the girl retained a scoliosis; the boy was cured without residual complaints or abnormalities. Osteomyelitis of the spine and sacroiliac joint are rare disorders in children. The subtle and non-specific symptoms sometimes make the diagnosis difficult. Conventional X-ray is the primary radiological investigation. Bone scintigraphy (99mTc-oxidronate) is useful in the initial evaluation of children with suspected osteomyelitis. It is sensitive, relatively inexpensive, often does not require sedation and can detect multiple foci of disease. MRI is also highly sensitive and more specific than bone scintigraphy, but it cannot be used as a screening technique when the site of pathology is unclear. MRI is useful when the bone scintigram is inconclusive and in complicated cases for better anatomic details.

Longitudinal analysis of growth and puberty in 21-hydroxylase deficiency patients

AIMS

To evaluate growth from diagnosis until final height (FH) in 21-hydroxylase deficiency patients.

METHODS

A retrospective longitudinal study was performed. Only patients treated with hydrocortisone and fludrocortisone (in case of salt wasting) were evaluated. This resulted in a sample of 34 (21 male, 13 female) salt wasting patients (SW) and 26 (13 male, 13 female) non-salt wasting patients (NSW). Auxological data were compared to recent Dutch reference values.

RESULTS

In the first three months of life, the mean length SDS decreased to -1.50, probably because of the high average glucocorticoid dose (40 mg/m2/day). FH corrected for target height (FH(corr)TH) was -1.25 and -1.27 SDS in females and males, respectively. Patients treated with salt supplements during the first year, had a better FH(corr)TH (-0.83 SDS). In NSW patients, FH(corr)TH was -0.96 and -1.51 SDS in females and males, respectively. In SW and NSW, age at onset of puberty was within normal limits, but bone age was advanced. Mean pubertal height gain was reduced in males. Body mass index was only increased in NSW females.

CONCLUSION

In SW, loss of final height potential might be a result of glucocorticoid excess in the first three months and sodium depletion during infancy. In NSW, loss of FH potential was caused by the delay in diagnosis. In SW and NSW, the advanced bone age at onset of puberty (undertreatment in prebertal years) resulted in loss of height gain during puberty. The effect of intensive sodium chloride support in early infancy should be examined prospectively. Neonatal screening is required if the height prognosis in NSW patients is to be improved.

Adult height in patients with early onset of Crohn's disease

BACKGROUND

Growth impairment during childhood and adolescence is a common problem faced by patients with an early onset of Crohn's disease.

AIMS

To establish how the final adult height is affected in patients with early onset of symptoms of Crohn's disease.

METHODS

Information on height, parental height, and disease history was obtained from 135 patients with Crohn's disease who reached their adult height (men 22-40 years, women 18-40 years) using a questionnaire and by outpatient measurement of height where possible. Subsequently, adult heights were expressed as standard deviation scores, with and without correction for the expected target height.

RESULTS

Patients with onset of disease before puberty were shorter compared with patients with onset in adulthood (p<0.01). This difference was not statistically significant when adult heights were corrected for parental height. Also, height standard deviation scores for those patients with onset of disease before puberty were significantly lower than those with onset of disease during puberty (p<0.05) but after correction for parental height the difference was not significant. The site of disease had no influence on adult height. Patients who had used corticosteroids during puberty were significantly shorter than patients who had not (p=0.005). This was also true when corrected for target height (p=0.007).

CONCLUSIONS

Although there was a trend indicating a deficit in adult height in patients with an early onset of Crohn's disease, once adjustment was made for parental height, this difference was not significant. Use of corticosteroids in puberty resulted in lower adult height.

[A flow diagram for the diagnosis of acute, non-traumatic joint complaints during childhood, retrospectively applied to 115 children]

Acute, non-traumatic joint complaints during childhood can be caused by conditions which require a quick and adequate recognition and treatment as well as by conditions in which an expectant policy can be pursued. On the basis of certain data from the anamnesis, supplemented with findings from the physical examination it is often possible to arrive at a (probable) diagnosis. An algorithm was designed, the differential steps of which were: fever, C-reactive protein titre, involvement of the hip joint, the presence of extra-articular manifestations and the results of a full blood count, erythrocyte sedimentation rate and imaging techniques. When this algorithm was retrospectively applied to the disease data of 115 children with acute, non-traumatic joint complaints, for whom the diagnosis in the status was taken as the gold standard, the correct diagnosis was established for every single child: for 98 (85.2%) by the shortest route and for 17 (14.8%) indirectly. In the case of 4 children, use of this algorithm would have led to unnecessary laboratory investigations and/or treatment. None of the diseases requiring immediate treatment were missed.

Gender differences in expression of androgen receptor in tibial growth plate and metaphyseal bone of the rat

In this study, we investigate the expression of the androgen receptor (AR) in the tibial growth plate and metaphyseal bone of male and female rats at the mRNA and protein level. Using in situ hybridization and immunohistochemistry, AR mRNA and protein were demonstrated in proliferating and early hypertrophic chondrocytes in the growth plate of 1-, 4-, and 7-week-old male and female rats. Immunostaining for AR was observed both in the nucleus and the cytoplasm. After sexual maturation at 12 and 16 weeks of age, AR expression decreased in both genders and was confined to a small rim of prehypertrophic chondrocytes. In female rats of 40 weeks of age, this expression pattern was still visible. In most age groups there was a tendency toward an increased AR mRNA expression in male vs. female rats except in the 7-week-old animals. At the protein level, sexually maturing 7-week-old male rats demonstrated a higher staining intensity compared to their female counterparts. At this stage, AR staining in the males was mainly confined to the nucleus, whereas in females staining was predominantly found in the cytoplasm. In the tibial metaphysis, AR mRNA was detected in lining cells, osteoblasts, osteocytes, and osteoclasts at all stages of development. At the protein level, a similar expression pattern was observed, except for an absence of immunostaining in the lining cells. The staining was both nuclear and cytoplasmic. In most age groups, mRNA and protein signals were higher in males compared with females. We have demonstrated the presence of AR mRNA and protein in the tibial growth plate and the underlying metaphyseal bone during development of the rat. In male rats, the presence of higher messenger and protein staining intensities, as well as preferential nuclear staining during sexual maturation, suggests that direct actions of androgens in chondrocytes and in bone forming cells may be involved in establishing the gender differences in the skeleton.

Dehydroepiandrosterone sulfate treatment for atrichia pubis

OBJECTIVE

To evaluate the efficacy of oral dehydroepiandrosterone sulfate (DHEAS) treatment for atrichia pubis in female adolescents.

STUDY DESIGN

Two XY female adolescents with 17-hydroxylase deficiency and 2 XX females with panhypopituitarism presenting with atrichia pubis were treated with a daily dosage of DHEAS 10 mg/m2 body surface in addition to their regular substitution therapy. The dosage was increased according to clinical response. Pubic hair stages, growth and serum DHEAS were evaluated and in 1 case also serum IGFs and IGFBPs.

RESULTS

A dosage of 10 mg/m2 for 1 year led to serum DHEAS levels at the lower limit of the normal range. 15 mg/m2 was needed to achieve pubic hair stage 4-5 and axillary hair in patients with 17-hydroxylase deficiency. In panhypopituitarism, pubic hair developed at a slower pace and reached stage 4 on a dosage of 25-30 mg/m2. Baseline serum IGF-I SDS was -0.67 and did not change on the initial dosage of DHEAS, in combination with submaximal estrogen substitution (10 microg ethinyl estradiol). On the combination of 15 mg/m2 DHEAS and full estrogen substitution, IGF-I SDS increased to an average of -0.15. IGFBP-3 SDS increased from 1.4 to a mean of 2.6 in the first year, and went back to 1.4 in the second year. IGFBP-6 SDS was low at baseline (-2.5) and rose to -1.9 and -1.7 IGF-II and IGFBP-1 showed an irregular pattern.

CONCLUSIONS

Oral administration of DHEAS in a dosage of 15 mg/m2 o.d. is an efficacious treatment for atrichia pubis. For females with a panhypopituitarism a higher dosage appears needed. Given this and other biological actions of DHEAS, substitution therapy with DHEAS or DHEA to females with adrenal androgen deficiency appears rational.

Skin fibroblasts of children with idiopathic short stature show an increased mitogenic response to IGF-I and secrete more IGFBP-3

OBJECTIVE AND PATIENTS

To study differences in cellular parameters of GH and IGF-I responsiveness in skin fibroblasts of 14 children with idiopathic short stature (ISS) treated with recombinant human GH and 13 children with normal height. Secondly, to investigate whether these cellular parameters can predict the growth response to GH treatment in children with ISS.

DESIGN AND MEASUREMENTS

The mitogenic responsiveness to GH and IGF-I was investigated by 3H-Thymidine incorporation. Insulin-like growth factor binding protein-3 (IGFBP-3) levels in the media were measured by radioimmunoassay (RIA).

RESULTS

No significant mitogenic responses were observed to various doses of GH (1000, 5000 or 50.000 ng/ml) in children with ISS or controls. ISS fibroblasts showed an increased mitogenic response to IGF-I (10 ng/ml) compared to controls (mean +/- SD 5.9 +/- 2.4- vs. 4.2 +/- 1.5-fold stimulation, P < 0.05), and GH enhanced this effect in both groups. IGFBP-3 secretion was increased in ISS fibroblasts when compared to controls under all conditions examined (basal, 200 and 5000 ng/ml GH, 10 ng/ml IGF-I for 24 and 48 h). High IGFBP-3 levels were related to low mitogenic responses to IGF-I or to GH + IGF-I in children with ISS (r = -0.7, P < 0.05), but not in controls. Within the ISS group, an enhanced mitogenic response to IGF-I in vitro was related to more extreme short stature before GH treatment (r = -0.70, P < 0.05) and to a relatively impaired response to high dose GH treatment in vivo (r = -0.52, P < 0.05).

CONCLUSION

The demonstration of high IGFBP-3 levels and enhanced mitogenic response to IGF-I shows that ISS fibroblasts have different cellular characteristics compared to controls of normal height. It is hypothesized that in ISS an alteration of the signal transduction pathway between the GH receptor and IGFBP-3 synthesis results in a local imbalance with high IGFBP-3 levels and lower IGF-I availability for the IGF-I receptor. This may be reflected by an increased IGF-I responsiveness in vitro which is associated with an impaired capacity to grow in vivo.

Expression of estrogen receptor alpha and beta in the epiphyseal plate of the rat

In this study we examine the spatial and temporal expression of estrogen receptor (ER) alpha and beta mRNA and protein in the tibial growth plate of the rat after birth, as well as the hormonal regulation of their expression. Using in situ hybridization and immunohistochemistry, we demonstrated ER alpha and ER beta mRNA and protein in tibial growth plates from 1 to 40 weeks after birth. ER alpha and beta mRNA and protein were localized in late proliferating and early hypertrophic chondrocytes during early life (1 and 4 weeks of age), whereas the immunohistochemistry also showed staining for ER alpha and beta in the resting cells. A similar expression pattern was observed during sexual maturation (7 weeks of age) except that ER beta mRNA was also detected in early proliferating chondrocytes. After sexual maturation (from 12 up to 40 weeks of age) ER alpha and beta mRNA and protein expression was confined to late proliferating and early hypertrophic chondrocytes. Apart from a relatively higher ER alpha mRNA expression in males after sexual maturation, we did not detect differences in expression of ERs between genders. Expression of ER beta mRNA in epiphyseal plates was increased in growth-retarded hypophysectomized rats compared with controls. Administration of growth hormone (GH) did not reverse the increased ER expression to normal. These data suggest that ER alpha and beta are coexpressed in growth plates of the rat after birth and that the level of expression of ERs in these tissues is hormonally regulated. Furthermore, our data indicate that the absence of growth-plate closure in the rat cannot be explained by disappearance of ER alpha expression during sexual maturation per se.

Final height gain by GH therapy in children with idiopathic short stature is dose dependent

Recombinant human GH therapy to children with idiopathic short stature (ISS) increases growth velocity, but its effect on final height (FH) is still uncertain. The aim of this study was to investigate the effect of recombinant human GH on FH of patients with ISS who were treated according to two protocols in comparison to untreated historical controls. In study 1 (n = 24), all patients were treated with 14 IU (4.6 mg)/m(2) body surface x wk in the first year; thereafter the dosage was doubled if the growth response was insufficient. In study 2 (n = 34), patients were randomized into three arms: 18 IU (6 mg)/m(2) x wk; 27 IU (9 mg)/m(2) x wk; and 18 IU/m(2) x wk in the first year, followed by 27 IU/m(2) x wk thereafter. Observed or estimated FH was available for 53 patients. Thirty-four untreated controls from the same centers were available for comparison. Mean FH SD score in GH-treated children was -2.1, vs. -2.4 in controls (-2.4) (NS), but height SD score gain (1.3 vs. 0.7) and the difference between FH and predicted adult height (4.0 vs. 0.8 cm) were significantly greater. The growth response on an initial dosage of 27 IU/m(2) x wk (6.9 cm) was significantly better than on other regimens (2.8 cm). We conclude that a GH dosage of 27 IU (9 mg)/m(2) x wk to prepubertal children with ISS leads to a mean FH gain of approximately 7 cm, whereas regimens starting on lower dosages are less efficacious.