The diagnostic work up of growth failure in secondary health care; An evaluation of consensus guidelines

Background

As abnormal growth might be the first manifestation of undetected diseases, it is important to have accurate referral criteria and a proper diagnostic work-up. In the present paper we evaluate the diagnostic work-up in secondary health care according to existing consensus guidelines and study the frequency of underlying medical disorders.

Methods

Data on growth and additional diagnostic procedures were collected from medical records of new patients referred for short stature to the outpatient clinics of the general paediatric departments of two hospitals (Erasmus MC – Sophia Children's Hospital, Rotterdam and Spaarne Hospital, Haarlem) between January 1998 and December 2002. As the Dutch Consensus Guideline (DCG) is the only guideline addressing referral criteria as well as diagnostic work-up, the analyses were based on its seven auxological referral criteria to determine the characteristics of children who are incorrectly referred and the adequacy of workup of those who are referred.

Results

Twenty four percent of children older than 3 years were inappropriately referred (NCR). Of the correctly referred children 74–88% were short corrected for parental height, 40–61% had a height SDS <-2.5 and 21% showed height deflection (Δ HSDS < -0.25/yr or Δ HSDS < -1). In none of the children a complete detailed routine diagnostic work up was performed and in more than 30% no routine laboratory examination was done at all. Pathologic causes of short stature were found in 27 children (5%).

Conclusion

Existing guidelines for workup of children with suspected growth failure are poorly implemented. Although poorly implemented the DCG detects at least 5% pathologic causes of growth failure in children referred for short stature. New guidelines for referral are required with a better sensitivity and specificity, wherein distance to target height should get more attention. The general diagnostic work up for short stature should include testing for celiac disease in all children and for Turner syndrome in girls.     

Characteristics of the short children referred to an academic paediatric endocrine clinic in Greece

Aim: To describe the characteristics of short children in relation to gender and the various diagnoses. Methods: All new patients of Greek origin that were referred to our institution in the years 2007 and 2008 for evaluation of short stature were included in the study. Children were categorized according to the severity of their short stature in those with height standard deviation score (HSDS) ≤?3 and HSDS >?3. Results: Two hundred ninety‐five children (162 boys and 133 girls, ratio 1.2) were referred. HSDS of boys was ?2.3 (0.6) and of girls ?2.1 (0.5), P= 0.004. Girls had shorter parents, and the predicted adult HSDS was also shorter for girls ?1.7 (0.8) than for boys ?1.35 (0.76), P= 0.003. Seventy per cent of the children of both sexes had familial short stature (FSS), constitutional delay of growth or a combination of the two conditions. About 10% presented the auxological and biochemical criteria for growth hormone deficiency (GHD). In addition, 11.8% had a HSDS ≤?3, the most common diagnosis being GHD (36.1%); the less severely short children most commonly presented FSS (41.2%). Conclusions: There is no gender bias in referrals for short stature in Greece. About 70% of children of both sexes presented FSS or constitutional delay of growth or a combination of the two conditions, whereas GHD was diagnosed in about 10% of the children. Normal variants of growth were present in about 80% of children with HSDS >?3, but in only 40% when HSDS was ≤?3.     

Growth acceleration and final height after treatment for delayed diagnosis of celiac disease

The only presenting clinical feature of diagnosing celiac disease (CD) late may be short stature. At the start of treatment with a gluten-free diet (GFD), celiac children show an accelerated growth rate. The real duration of catch-up growth and influence of diet on the final stature has not yet been defined. In order to evaluate the effect of a GFD on growth parameters, 24 children diagnosed late with CD were studied at our center. During the period of diagnosis, weight, height standard deviation score (HSDS), weight and height velocities (WV and HV), bone age (BA), and pubertal stage were recorded. Predicted height (PH) according to the Tanner method, parental height, and target height (TH) were also evaluated at diagnosis. All patients initially presented because of short stature or retarded growth (100% of patients with height less than 5th percentile). Patients showed an increased HV and WV during the first 3 years on a GFD, with maximum growth velocity occurring during the first year, but the catch-up growth was incomplete over 3 years (mean HSDS +/- SD, -1.77 +/- 0.6). Puberty began in all patients at a normal age. The 12 patients who completed pubertal development reached their target height, whatever the duration of the GFD. The final height (between the 1st and 25th percentile) seemed influenced mainly by familial characteristics; height was below the 3rd percentile in 31% of parents examined.     

Growth hormone treatment in 35 prepubertal children with achondroplasia: a five-year dose-response trial

BACKGROUND: Achondroplasia is a skeletal dysplasia with extreme, disproportionate, short stature. AIM: In a 5-y growth hormone (GH) treatment study including 1 y without treatment, we investigated growth and body proportion response in 35 children with achondroplasia. METHODS: Patients were randomized to either 0.1 IU/kg (n = 18) or 0.2 IU/kg (n = 17) per day. GH treatment was interrupted for 12 mo after 2 y of treatment in prepubertal patients to study catch-down growth. Mean height SDS (HSDS) at start was -5.6 and -5.2 for the low- and high-dose groups, respectively, and mean age 7.3 and 6.6 y. RESULTS: Mean growth velocity (baseline 4.5/4.6 cm/y for the groups) increased significantly by 1.9/3.6 cm/y during the first year and by 0.5/1.5 cm/y during the second year. During the third year, a decrease of growth velocity was observed at 1.9/1.3 cm/y below baseline values. HSDS increased significantly by 0.6/0.8 during the first year of treatment and in total by 1.3/1.6 during the 5 y of study. Sitting height SDS improved significantly from -2.1/-1.7 to -0.8/0.2 during the study. Body proportion (sitting height/total height) or arm span did not show any significant change. CONCLUSION: GH treatment of children with achondroplasia improves height during 4 y of therapy without adverse effect on trunk-leg disproportion. The short-term effect is comparable to that reported in Turner and Noonan syndrome and in idiopathic short stature.     

Growth monitoring: testing the new guidelines

OBJECTIVE: To assess the impact of recent guidelines from the UK joint working party of child health surveillance recommending that all children be measured at age 5 and again between 7 and 9 years of age to determine how many normal school age children are likely to be referred for specialist assessment. METHODS: The longitudinal data of 486 children measured by school nurses in a community setting were examined and compared with measurements made in a research setting by a single, skilled observer. MAIN OUTCOME MEASURES: Number of children identified as having abnormal stature (< 0.4th or > 99.6th centile) and abnormal growth rate height standard deviation score (HSDS) change > 0.67). RESULTS: The community survey identified seven (1.4%) children as having abnormal stature (four short, three tall), 11 (2.3%) were identified as "slow growing", and nine (1.9%) increased their HSDS by more than 0.67. These results were comparable to data collected in ideal research conditions. CONCLUSIONS: Following the recommendations would not result in an excess number of inappropriate referrals. However, this study highlights several unresolved issues such as interobserver variability and time interval between measurements. A large scale prospective study should be considered to establish realistic and cost-effective criteria before implementation of a national screening programme.     

Preliminary validation of a prediction model for the short-term growth response to growth hormone therapy in children with idiopathic short stature

A discriminant scoring system, using multivariate analysis, has been developed for pretreatment prediction of responsiveness to a 6-month trial of growth hormone (GH) treatment in short children with subnormal growth velocity, but without GH deficiency. Inclusion criteria included a birth weight above 2.5 kg, height below the 3rd centile for chronological age, height velocity below the 25th centile for bone age, no signs of puberty, a maximal GH response to pharmacological stimulation of above 10 μg/l and treatment with GH at a dose of 12–16 IU/m²/week. Children with an increase in height velocity greater than 2.5 cm/year after therapy were considered to be responders. Pretreatment clinical data from 67 patients were employed in a discriminant analysis in order to establish the model. The scoring system developed was as follows: score = -0.4 + 0.92X₁– 0.87X₂, where X₁ is the height velocity SD score (SDS) for chronological age, and X₂ is the bone age SDS for chronological age. This model had a specificity of 96.3% and a sensitivity of 92.5% in predicting the responsiveness to GH. The model has subsequently been applied to a group of 14 patients in order to establish its validity; in this group its sensitivity was 83.3% and its specificity 100%. These preliminary data suggest that the model can be used as a guideline for selecting short, slowly growing, non-GH-deficient children who will respond to short-term GH therapy.     

Growth pattern and final height in 21-hydroxylase deficiency

Growth pattern and final height were evaluated in 47 children with 21-hydroxylase deficiency to identify factors influencing growth. The subjects were followed-up from the age of 0.6 +/- 1.2 years for 8.8 +/- 3.9 years. Final height SDS was significantly below target height SDS (- 2.5 +/- 1.4 versus - 1.0 +/- 1.0, P < 0.001). Laboratory monitoring and type of disease (salt-wasting or simple virilizing) significantly influenced age-specific height SDS. Age at treatment, frequency of laboratory monitoring and dose of glucocorticoid during infancy influenced final height on univariate analysis; the effect was not sustained on multivariate analysis. Our study emphasizes the need for regular laboratory monitoring and lower glucocorticoid dose during infancy in 21-hydroxylase deficiency.     

Growth of asthmatic children is slower during than before treatment with inhaled glucocorticoids

Reports on the influence of inhaled glucocorticoids on growth have been controversial. We studied the growth of prepubertal asthmatic children prior to and during glucocorticoid therapy. We collected retrospectively the notes of 201 asthmatic children aged 1–11 years receiving inhaled beclomethasone dipropionate or budesonide. We calculated their height and height velocity standard deviation scores (HSDS and HVSDS, respectively) before the treatment and up to 5 years during the treatment and compared those with the growth of healthy peers. The dose of the medication was calculated and the severity of asthma was assessed. The asthmatic children grew similarly to their healthy peers before treatment with inhaled glucocorticoids: the mean HSDS was +0.02 and the mean HVSDS +0.01 for boys and -0.16 and +0.13 for girls, respectively. Growth retardation took place soon after the start of the treatment, the most profound decrease in the growth velocity (the change in the mean HVSDS from +0.05 to -0.88) occurring during the first year of treatment. The growth-retarding effect of inhaled glucocorticoids was not dose dependent. In the covariance analysis the increasing severity of asthma had a significant interaction with repeated measurements, showing more growth retardation along with more severe asthma, especially during long-term treatment. Asthma per se does not impair growth, but inhaled glucocorticoids may do so. Careful monitoring of the growth of all asthmatic children receiving inhaled glucocorticoids is necessary because the growth-retarding effect of the medication is not dose dependent. Individual sensitivity might explain the differences seen in the growth patterns of children receiving inhaled glucocorticoids.     

Longitudinal follow-up of growth in children born small for gestational age

Postnatal growth was followed in a population-based group of 123 small-for-gestational-age (SGA, birth weight < -2 SD) children (66 boys and 57 girls) to four years of age in order to determine the incidence and time of catch-up growth. Gestational age was determined by ultrasound in gestational weeks 16–17 in all pregnancies, thus eliminating the problem of distinguishing between SGA and preterm infants. Infants with well-defined causes for slow growth rate, i.e. those infants with chromosomal disorders, severe malformations, intrauterine viral infections or cerebral palsy, were excluded. The boys showed an extremely fast weight catch-up, 85% of them reaching weights greater than -2 SD at the age of three months and remaining above this level to the end of the study period. Such a fast catch-up growth was observed in only two-thirds of the girls, but at four years of age 85?4 of the girls were also above -2SD. Length catch-up was more gradual than weight catch-up. Of the boys, 54% had lengths below -2 SD at birth, 26% at 1 year of age, 22% at 2 years of age, 17% at 2.5 years of age and 11% (n= 8) at 4 years of age. Corresponding figures for girls were: 69% at birth, 28%) at 1 year, 15% at 2 years, 12% at 2.5 years and 5%) (n = 3) at 4 years. At 4 years of age, only six boys and three girls remained below -2 SD for both weight and height. We conclude that in Sweden the prognosis for catch-up growth for an SGA child, when children with well-defined causes of growth disturbances are excluded, is very good and it is extremely rare for the child still to have a height below -2 SD by the age of 4 years.     

Final height in a group of untreated children with constitutional growth delay

We retrospectively evaluated the growth of 41 children with constitutional growth delay followed till adulthood and never treated with growth-promoting therapies. Final height has been correlated with prepubertal height, genetic target and height prediction calculated in both prepuberty and puberty. All patients showed a significant improvement of their height standard deviation score (HSDS) from prepuberty to adulthood, and the great majority of them achieved a final height above the 3rd percentile. Moreover, we found a good correlation between final height and both genetic target and height prediction, even if the latter overestimated final height in 25% of the patients. In conclusion, our data confirm that constitutional growth delay is a normal variant of growth. Therefore, caution should be paid in considering pharmacological treatment of this condition.     

Reduced insulin sensitivity during growth hormone therapy for short children born small for gestational age

OBJECTIVES: To examine the influence of recombinant human growth hormone (rhGH) therapy on insulin sensitivity in short children born small for gestational age (SGA). STUDY DESIGN: Twelve short (height standard deviation score, -3.2 +/- 0.1) non-GH-deficient children SGA (7 boys/5 girls) were studied at 9.3 +/- 1.0 years of age. The insulin sensitivity index was measured with Bergman's minimal model before (11 children) and during (12 children) rhGH therapy (21 +/- 6 months) administered daily at 20 IU/m(2) per week. No child had a change in pubertal status during the study. In addition, 5 children who remained prepubertal had insulin sensitivity remeasured 3 months after rhGH therapy was suspended. RESULTS: With rhGH therapy, insulin sensitivity fell 44% +/- 10% (P =.018), with a compensatory rise in the acute insulin response of 123% +/- 59% (P <.009). Reassessment of insulin sensitivity in 5 children (3 boys/2 girls) 3 months after suspension of rhGH occurred at 9.9 +/- 0.7 years. Insulin sensitivity remained unchanged after rhGH therapy was stopped: 31.6 (20.5-42.3) before treatment, 11.5 (5.7-24.4) with treatment, and 10.7 (6.2-16.9) 10(-4). min(-1) microU/mL after treatment. CONCLUSIONS: Children SGA are known to have reduced insulin sensitivity. There was a further reduction in insulin sensitivity with rhGH therapy that did not recover 3 months after rhGH therapy was stopped.     

Prediction of height achievement at five years of age in children born very preterm or with very low birth weight: continuation of catch-up growth after two years of age

To predict height at five years in a cohort of 565 very preterm and/or very low-birth-weight children, hypothesized growth determinants were subjected to discriminant analysis. Many neonatal parameters were not significantly associated with short stature at five years of age. A correct classification of stature (smaller/larger than the 10th percentile at five years of age) could be obtained in 85% of children, using the following variables: height at two years of age; total (or mid) parental height; parental level of education; length at one year of age; hypertension during pregnancy; sex; weight at two years of age; length percentile at one year of age. However, when compared to actual longitudinal data, the false-positive rate was 37%. The survey also demonstrated the continuing catch-up growth in very preterm and very low-birth-weight infants after two years of age.     

Final height of short subjects of low birth weight with and without growth hormone treatment.

AIM: To compare final height in two groups of low birth weight children examined for short stature: the first group untreated because of normal growth hormone (GH) secretion, the second treated with human growth hormone (hGH) because of abnormal secretion. METHODS: A total of 49 subjects born at term of birth weight below the 10th centile were consecutively examined for idiopathic short stature. The first group of subjects (n = 20) with normal GH peaks after pharmacological tests (>8 microg/l) spontaneously reached final height. The second group (n = 29) with abnormal secretion were treated with hGH (20 U/m(2)/week) for 36-84 months. At diagnosis the two groups were of similar height for chronological age and bone age, and had similar target height. RESULTS: In both groups final height was significantly lower than target height (-0.65 (SEM 0.20) in untreated cases, -0.61 (0.18) in treated cases). Fewer than one third of subjects had a final height above target height. Final height data of untreated and treated cases were not different. In the treated group the best results were obtained by those subjects who improved their height for bone age after three years of therapy. CONCLUSIONS: Our subjects with birth weight below the 10th centile remained as short adults with final height below target height. Treatment with hGH 20 U/m(2)/week in those diagnosed as deficient was not effective, with final results overlapping those of untreated subjects.     

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.     

Final height in short children born small for gestational age treated with growth hormone

The aim of this observational study was to assess the long-term growth responses to GH treatment of children born small for gestational age (SGA). GH treatment was begun before puberty and continued to final height (FH). Seventy-seven short (height SD score below -2) prepubertal children born SGA (below -2 SD for birth weight and/or birth length), with a broad range of GH secretory capacity, were treated with GH in a daily dose of 33 microg/kg (0.1 U/kg), beginning before the onset of puberty. We observed a difference between adult and pretreatment projected height of 1.3 SD (9 cm) for the entire group. Among the children treated for >2 y before puberty, this mean gain (i.e. difference) in final height was 1.7 SD, whereas the mean gain was 0.9 SD among those in whom treatment was begun <2 y before puberty. Better catch-up growth was observed in the younger (r=-0.56, p<0.0001), shorter (r=-0.49, p<0.0001), and lighter (r=-0.46, p<0.0001) subjects. We conclude that GH treatment improves the final height of short children born SGA. The height gain attained before the onset of puberty is maintained to final height. The younger, shorter, and lighter the child at the start of GH treatment, the better the response. Moreover, most of these SGA individuals treated with GH reach their target height.     

The Wessex Growth Study: First Report

Voss, L., Walker, J., Lunt, H., Wilkin, T. and Betts, P. (Department of Paediatrics and the Endocrine Section, Department of Medicine II, General Hospital, Southampton, UK). The Wessex growth study: first report. Acta Paediatr Scand [Suppl] 349: 65, 1989.
The Wessex Growth Study is a community-based longitudinal survey of short children recruited from two Health Districts in Wessex during 1985–86 (cohort I) and 1986–87 (cohort II). Screening of new school entrants during 1985–86 identified only 1.3% who were at or below the 3rd centile for height as defined by Tanner and Whitehouse, suggesting a strong secular trend and an urgent need for updated height charts. After exclusion of the small number of children with underlying organic pathology and those from ethnic minorities, there were 84 children in cohort I on whom this report is based. These apparently normal, short children were sex- and age-matched with normal controls (10th-90th centile) from the same school class. Forty-two per cent of cohort I had a delayed bone age, and 34% lay above the 3rd centile after correction for parental height. Forty-four per cent were of low birth weight. The correlation between two successive height velocities measured at 6 and 12 months was only -0.14 for cohort I and -0.15 for their controls. Twelve-month mean height velocity SD scores (SDS) were -0.45 and +0.25, respectively, corresponding to the 33rd and 60th centiles, and rather higher than the 25th and 50th centiles expected in view of the heights of these children. Thirty-eight per cent of cohort 1 had a 12-month height velocity below the 25th centile, and in 16% height velocity was below the 10th centile. As a group, the children in cohort I grew more slowly than their controls, hut the height velocity in 88% of cases lay within the control range. For any individual, therefore, 12-month height velocity was not a useful discriminant of growth failure. Repeated measurements are indicated.     

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.     

Randomised controlled trial of recombinant human growth hormone in prepubertal and pubertal renal transplant recipients. British Association for Pediatric Nephrology.

AIMS: To evaluate the efficacy (height velocity (HV), change in height standard deviation score (delta HSDS)), and safety (glomerular filtration rate (GFR), incidence of rejection, and calcium and glucose metabolism) of recombinant human growth hormone (rhGH) treatment after renal transplantation. DESIGN: A two year randomised controlled trial. SUBJECTS: Fifteen prepubertal and seven pubertal children: mean (SD) age, 13.0 (2.6) and 15.2 (2.4) years, respectively; mean (SD) GFR, 51 (30) and 48 (17) ml/min/1.73 m2, respectively. Six prepubertal and three pubertal children were controls during the first year; all received rhGH in the second year. RESULTS: In the first year, mean (SE) HV and delta HSDS in the prepubertal treated group increased compared with controls: 8.1 (0.9) v 3.7 (0.6) cm/year and 0.6 (0.1) v -0.3 (0.2), respectively. In the pubertal treated group, mean (SE) HV and delta HSDS were also greater: 10.1 (0.6) v 3.9 (1.3) cm/year and 0.6 (0.1) v -0.1 (0.2), respectively. Comparing all treated and control children, there was no significant change in GFR: treated group, mean (SE) 9.9 (5.4) ml/min/1.73 m2 v control group, -1.6 (7.6) ml/min/1.73 m2. There were also no differences in the incidence of rejection in the first year: eight episodes in 13 patients v five episodes in nine patients, respectively. Phosphate, alkaline phosphatase (ALP), parathyroid hormone (PTH), and fasting insulin concentrations rose during the first year of treatment, but not thereafter. In the second year of treatment, HV remained above baseline. CONCLUSION: Treatment with rhGH improves growth in prepubertal and pubertal children with renal transplants, with no significant change in GFR or the incidence of rejection. Phosphate, ALP, PTH, and insulin increased during the first year of treatment.     

Growth charts suitable for evaluation of Indian children

OBJECTIVE: To assess the suitability of recently published reference anthropometric data for evaluation of the growth of children in our region. SETTING: Referral Pediatric Endocrinology Clinic in tertiary level care hospital. SUBJECTS: 280 normal school children and 155 children referred for growth retardation to the clinic in 1993 and 1994. METHODS: Heights of school children were plotted on growth charts created from recently published reference growth data of children from high socioeconomic group families. The case records of 155 children referred for growth evaluation were retrospectively analyzed for (i) etiology of short stature, (ii) height percentile based on previously used Indian Council of Medical Research (ICMR) references, and (iii) height percentile and standard deviation scores based on the new references. RESULTS: 93% of school children fell above and 7% below the 5th centile of the new height references. Of the 129 clinic children diagnosed to have growth retardation, 128 fell below the 5th centile of the new references. However, 38 of these (29.5%) fell above the 5th centile of ICMR references. These included patients with pathological causes of short stature. Twenty four of 26 children labelled as having no growth problem fell above the 5th centile of new reference data. CONCLUSIONS: The 5th height centile of new reference data from high socioeconomic group children is an appropriate cut off below which to evaluate children for short stature in our region. It will allow earlier identification and treatment than the hitherto used ICMR percentiles, and yet is not expected to result in over investigation of normal children.