Short dialyzed children respond less to growth hormone than patients prior to dialysis. German Study Group for Growth Hormone Treatment in Chronic Renal Failure

Incremental hemodialysis in pediatric patients

BACKGROUND

Incremental hemodialysis follows the concept of adjusting dialysis dose according to residual kidney function. Data on incremental hemodialysis in pediatric patients is lacking.

METHODS

We conducted a retrospective analysis of children initiating hemodialysis between January 2015 and July 2020 in a single tertiary center, comparing the characteristics and outcomes of those who commenced with incremental hemodialysis vs with conventional thrice-weekly regimen.

RESULTS

Data on forty patients, 15 (37.5%) on incremental hemodialysis and 25 (63%) on thrice-weekly hemodialysis were analyzed. No differences in age, estimated glomerular filtration rate and metabolic parameters were noted between groups at baseline, but there were more males (73 vs 40%, p = 0.04), more patients with congenital anomalies of kidney and urinary tract (60 vs 20%, p = 0.01), higher urine output (2.5 ± 1 vs 1 ± 0.8 ml/kg/h, p < 0.001), lower use of antihypertensive medications (20 vs 72%, p = 0.002) and lower prevalence of left ventricular hypertrophy (6.7 vs 32%, p = 0.003) in the incremental hemodialysis group vs thrice-weekly hemodialysis. During follow up, 5 (33%) incremental hemodialysis patients were transplanted, 1 (7%) remained on incremental hemodialysis at 24 months, and 9 (60%) transitioned to thrice-weekly hemodialysis at a median (IQR) time of 8.7 (4.2, 11.8) months. At last follow up, fewer patients who initiated incremental hemodialysis had left ventricular hypertrophy (0 vs 32%, p = 0.016) and urine output < 100 ml/24 h (20 vs 60%, p = 0.02) compared to thrice-weekly hemodialysis, with no significant differences in metabolic or growth parameters.

CONCLUSION

Incremental hemodialysis is a viable option for initiating dialysis in selected pediatric patients, that may help improve patients' quality of life and reduce dialysis burden without compromising clinical outcome.

Management of Short Stature: Use of Growth Hormone in GH-Deficient and non-GH-Deficient Conditions

Growth hormone (GH) is an important driver for somatic growth and increase in height in children. The development of recombinant human GH has greatly increased its availability, and hence the potential for its use and abuse. GH therapy should only be offered to patients with established and approved indications. Common pediatric indications for treatment include growth hormone deficiency, Turner syndrome, Prader-Willi syndrome, small for gestational age, chronic renal insufficiency, and idiopathic short stature. Before initiating treatment, the family should be counseled about the treatment goals, costs, and possible adverse effects from the treatment. It is important for patients to have realistic expectations from the treatment. The dose of GH should be individualized for the indication and will require titration in each patient based on response to the treatment and the adverse effects. Overall, GH has a good safety record. However, GH treatment has many potential and real adverse effects that need to be considered and monitored during treatment. Recently, safety concerns regarding the long-term effect of GH therapy on cardiovascular morbidity have come under scrutiny.

Peritoneal Loss of Growth Hormone in Children on Automated Peritoneal Dialysis

Objective

To provide quantitative data regarding the daily dialytic loss of growth hormone (GH) in children on peritoneal dialysis (PD).

Design

Prospective study involving 24-hour dialysate collections on 3 consecutive days in patients with and without recombinant human GH (rhGH) treatment.

Setting

Single-center outpatient PD program.

Patients

Twenty-six children undergoing automated PD (APD): 6 with and 20 without daily rhGH.

Main Outcome Measures

Daily peritoneal losses of GH, α1-, β2-microglobulin, transferrin, and albumin.

Results

The mean (±SEM) daily dialytic GH loss was 2.18 ± 0.62 μg/1.73 m2 per day in rhGH-treated patients and 0.42 ± 0.28 μg/1.73 m2 per day in untreated patients, ( p < 0.05). The intraindividual coefficient of variation of daily GH loss was 65%. The peritoneal loss of GH was positively correlated with that of β2-microglobulin ( r = 0.77, p < 0.001) and α1-microglobulin ( r = 0.51, p < 0.01). The variability in β2-microglobulin and α1-microglobulin elimination, together with the use of rhGH, explained 66% of the total variability of daily GH excretion. In patients without rhGH therapy, the daily peritoneal GH loss was approximately 0.05% of the estimated daily endogenous production rate based on previous estimates in children with end-stage renal failure. In patients on rhGH therapy, less than 0.1% of the injected rhGH dose was eliminated by dialysis.

Conclusion

Peritoneal losses of GH in children on APD account only for a minute fraction of endogenous metabolic clearance, and do not explain the variability of the rhGH treatment response. The assessment of dialytic GH elimination may be used to estimate time-integrated mean plasma GH concentrations, and to monitor rhGH treatment compliance.

Clinical practice recommendations for growth hormone treatment in children with chronic kidney disease

Achieving normal growth is one of the most challenging problems in the management of children with chronic kidney disease (CKD). Treatment with recombinant human growth hormone (GH) promotes longitudinal growth and likely enables children with CKD and short stature to reach normal adult height. Here, members of the European Society for Paediatric Nephrology (ESPN) CKD–Mineral and Bone Disorder (MBD), Dialysis and Transplantation working groups present clinical practice recommendations for the use of GH in children with CKD on dialysis and after renal transplantation. These recommendations have been developed with input from an external advisory group of paediatric endocrinologists, paediatric nephrologists and patient representatives. We recommend that children with stage 3–5 CKD or on dialysis should be candidates for GH therapy if they have persistent growth failure, defined as a height below the third percentile for age and sex and a height velocity below the twenty-fifth percentile, once other potentially treatable risk factors for growth failure have been adequately addressed and provided the child has growth potential. In children who have received a kidney transplant and fulfil the above growth criteria, we recommend initiation of GH therapy 1 year after transplantation if spontaneous catch-up growth does not occur and steroid-free immunosuppression is not a feasible option. GH should be given at dosages of 0.045–0.05 mg/kg per day by daily subcutaneous injections until the patient has reached their final height or until renal transplantation. In addition to providing treatment recommendations, a cost-effectiveness analysis is provided that might help guide decision-making.

This Evidence-Based Guideline developed by members of the European Society for Paediatric Nephrology CKD-MBD, Dialysis and Transplantation working groups presents clinical practice recommendations for the use of growth hormone in children with chronic kidney disease on dialysis and after renal transplantation.

Twenty years of growth hormone treatment in dialyzed children in Poland-Results of national multicenter study

PURPOSE

The aim of the study was to analyze the effect of recombinant human growth hormone (rhGH) therapy and to establish factors influencing growth rate in dialyzed children in Poland.

METHODS

We retrospectively analyzed medical records of 81 children with end-stage renal disease (ESRD) on chronic dialysis treated with rhGH for ≥12 months between 1994 and 2014. The following data were recorded: cause of ESRD, dialysis modality, age at the dialysis and rhGH initiation [years]. In addition, growth [cm], [standard deviation score - SDS], body mass index [SDS], skeletal age [years], bone mineral density [SDS], hemoglobin, total protein, albumin, urea, creatinine, calcium, phosphorus, calcium phosphorus product, PTH, and alkaline phosphatase were measured at the baseline and after 12 months.

RESULTS

Growth velocity in 81 children during one-year rhGH treatment was 7.33 ± 2.63 cm (ΔSDS 0.36 ± 0.43). Height SDS increased significantly (-3.31 ± 1.12 vs. -2.94 ± 1.15, p < 0.001). Children on peritoneal dialysis (PD) (n = 51) were younger than children on hemodialysis (HD) (n = 30) (9.92 ± 3.72 vs. 12.32 ± 3.11 years, p = 0.003). ΔSDS did not differ between PD and HD children (0.40 ± 0.33 vs. 0.30 ± 0.47, p = 0.311). Growth velocity (ΔSDS) correlated with age at dialysis initiation (r=-0.30, p = 0.009), age at rhGH treatment initiation (r=-0.35, p = 0.002), skeletal age (r=-0.36, p = 0.002), BMI SDS (r=-0.27, p = 0.019), and PTH (r=-0.27, p = 0.017). No correlation between growth velocity and other parameters was observed.

CONCLUSIONS

Treatment with rhGH in children with ESRD is effective and safe irrespective of dialysis modality. Early initiation of rhGH therapy is a crucial factor determining response to the treatment in children with ESRD.

Growth hormone therapy in children with CKD after more than two decades of practice

This review focuses on the evidence for the efficacy and safety of recombinant human growth hormone (rhGH) therapy in children with all stages of chronic kidney disease (CKD) and at all ages. It describes the improving height prognosis for our patients both with and without rhGH; explains the underlying hormonal abnormalities that provide the rationale for rhGH use in CKD and the endocrine changes that accompany treatment; and views on who warrants treatment, with what dose, and how long for.

Growth impairment in children with pre-dialysis chronic kidney disease in Japan

BACKGROUND

Growth impairment is a major complication of chronic kidney disease (CKD) in children. However, no cohort studies have examined the growth of Asian children with pre-dialysis CKD.

METHODS

We sent cross-sectional surveys to 113 Japanese medical institutions that were treating 447 children with CKD stages 3-5 in 2010 and 2011. Of 447 children included in our survey conducted in 2010, height and CKD stage were evaluable for 297 children in 2011, and height standard deviation score (height SDS) was calculated in these children.

RESULTS

Height SDS decreased with increasing CKD stage (P < 0.001) in boys and girls. Height SDS also decreased significantly with increasing CKD stage among patients with congenital anomalies of the kidney and urinary tract (P < 0.001). Risk factors for growth impairment included CKD stages 4 and 5 (relative to stage 3), being small-for-date, and asphyxia at birth. Among children with a height SDS ≤-2.0, growth hormone was used in 19.5, 31.0, and 25.0 % of children with CKD stages 3, 4, and 5, respectively.

CONCLUSIONS

This prospective cohort study revealed marked growth impairment in Japanese children with CKD stages 3-5 relative to healthy children. CKD-related risk factors for growth impairment included advanced CKD (stages 4 and 5), being small-for-date, and asphyxia at birth. Growth hormone was infrequently used in this cohort of children with pre-dialysis CKD.

Growth hormone, insulin-like growth factor-1, and the kidney: pathophysiological and clinical implications

Besides their growth-promoting properties, GH and IGF-1 regulate a broad spectrum of biological functions in several organs, including the kidney. This review focuses on the renal actions of GH and IGF-1, taking into account major advances in renal physiology and hormone biology made over the last 20 years, allowing us to move our understanding of GH/IGF-1 regulation of renal functions from a cellular to a molecular level. The main purpose of this review was to analyze how GH and IGF-1 regulate renal development, glomerular functions, and tubular handling of sodium, calcium, phosphate, and glucose. Whenever possible, the relative contributions, the nephronic topology, and the underlying molecular mechanisms of GH and IGF-1 actions were addressed. Beyond the physiological aspects of GH/IGF-1 action on the kidney, the review describes the impact of GH excess and deficiency on renal architecture and functions. It reports in particular new insights into the pathophysiological mechanism of body fluid retention and of changes in phospho-calcium metabolism in acromegaly as well as of the reciprocal changes in sodium, calcium, and phosphate homeostasis observed in GH deficiency. The second aim of this review was to analyze how the GH/IGF-1 axis contributes to major renal diseases such as diabetic nephropathy, renal failure, renal carcinoma, and polycystic renal disease. It summarizes the consequences of chronic renal failure and glucocorticoid therapy after renal transplantation on GH secretion and action and questions the interest of GH therapy in these conditions.

Growth hormone in chronic renal disease

Severe growth retardation (below the third percentile for height) is seen in up to one-third children with chronic kidney disease. It is thought to be multifactorial and despite optimal medical therapy most children are unable to reach their normal height. Under-nutrition, anemia, vitamin D deficiency with secondary hyperparathyroidism, metabolic acidosis, hyperphosphatemia, renal osteodystrophy; abnormalities in the growth hormone/insulin like growth factor system and sex steroids, all have been implicated in the pathogenesis of growth failure. Therapy includes optimization of nutritional and metabolic abnormalities. Failure to achieve adequate height despite 3-6 months of optimal medical measures mandates the use of recombinant GH (rGH) therapy, which has shown to result in catch-up growth, anywhere from 2 cm to 10 cm with satisfactory liner, somatic and psychological development.

Growth hormone for children with chronic kidney disease

BACKGROUND

Growth retardation is a common complication of chronic kidney disease (CKD) in children and is of concern to families. Recombinant human growth hormone (rhGH) treatment has been used to help short children with CKD attain a height more in keeping with their age group. However there are concerns about the long-term benefits of rhGH in significantly improving adult height as well as concerns about potential adverse effects (deterioration in native kidney function, increased acute rejection in kidney transplant recipients, benign intracranial hypertension).

OBJECTIVES

To evaluate the benefits and harms of rhGH treatment in children with CKD.

SEARCH METHODS

Randomised controlled trials (RCTs) were identified from the Cochrane Renal Group's Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 12, 2011), MEDLINE (from 1966), EMBASE (from 1980), article reference lists and through contact with local and international experts in the field.Date of last search: December 29, 2011

SELECTION CRITERIA

RCTs were included if they were carried out in children aged zero to 18 years, diagnosed with CKD, who were pre-dialysis, on dialysis or post-transplant; if they compared rhGH treatment with placebo/no treatment or two doses of rhGH treatments; and if they included height outcomes.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for risk of bias and extracted data from eligible studies. Data was pooled using a random effects model with calculation of mean difference (MD) for continuous outcomes with 95% confidence intervals (CI).

MAIN RESULTS

Sixteen studies (enrolling 809 children) were identified. Risk of bias assessment indicated that study quality was poor or poorly reported with only four and five studies respectively reporting adequate allocation concealment or blinding of study participants and investigators. Treatment with rhGH (28 IU/m²/wk) compared with placebo or no specific therapy resulted in a significant increase in height standard deviation score (HSDS) at one year (8 studies, 391 children: MD 0.82, 95% CI 0.56 to 1.07), and a significant increase in height velocity at six months (2 studies, 27 children: MD 2.85 cm/6 mo, 95% CI 2.22 to 3.48) and one year (7 studies, 287 children: MD 3.88 cm/y, 95% CI 3.32 to 4.44). Height velocity, though reduced, remained significantly greater than untreated children during the second year of therapy (1 study, 82 children: MD 2.30 cm/y, 95% CI 1.39 to 3.21). Compared to the 14 IU/m²/wk group, there was a 1.18 cm/y increase in height velocity in the 28 IU/m²/wk group (3 studies, 150 children: 1.18 cm/y, 95% CI 0.52 to 1.84) . The frequency of reported side effects of rhGH was generally similar to that of the control group.

AUTHORS' CONCLUSIONS

One year of 28 IU/m²/wk rhGH in children with CKD resulted in a 3.88 cm increase in height velocity above that of untreated patients. Studies were too short to determine if continuing treatment resulted in an increase in final adult height.

Peritoneal dialysis in children with end-stage renal disease

Peritoneal dialysis is the preferred chronic dialysis modality for most children owing to its almost universal applicability and superior compatibility with lifestyle over other modalities. Although technological advances and increasing clinical experience have impacted favorably on patient and technique survival, clinical research in pediatric peritoneal dialysis has been hampered by the low incidence of end-stage renal disease (ESRD) in the pediatric population. To overcome this limitation, several international registries have emerged in the past few years to complement other long-standing registries, which together have provided useful information regarding technique-specific complications and comorbidities associated with ESRD in children undergoing chronic peritoneal dialysis. In this Review, we summarize the most relevant findings from these studies, highlighting the substantial variation in patient conditions, peritoneal dialysis practices and management of comorbidities encountered in different parts of the world.

Predicting the response to growth hormone treatment in short children with chronic kidney disease

CONTEXT

Short stature in children with chronic kidney disease (CKD) is due to various underlying congenital or acquired renal disorders resulting in variable impairment of renal function and variable response to GH treatment.

OBJECTIVE

It was the aim to develop a mathematical model that allows the prediction of the individual growth response and to identify nonresponders.

DESIGN

Data from 208 prepubertal children on conservative or dialysis treatment in a large pharmaco-epidemiological survey, the KIGS (Pfizer International Growth Database), were used for the model and data from 67 similar CKD patients registered at the Dutch Growth Research Foundation for validation.

RESULTS

Annualized height velocity (centimeters per year) during the first year of GH treatment was best predicted by age at start, weight sd score, underlying renal disorder (hereditary kidney disorder), glomerular filtration rate (at baseline), and GH dosage. Using these parameters, the final model explained 37% of the overall variability of growth response. Standard error of the estimates was 1.6 cm. Age was the most important predictor of growth response (20.3% of variability) followed by weight sd score at start, and 27.2% of the variability of the second-year response could be predicted by the first-year response and glomerular filtration rate. Nonresponders of the validation group could be correctly identified.

CONCLUSION

Based on simple clinical variables, a robust prediction model was developed that provides realistic expectations of individual growth response to GH in short children with CKD. The model will help in identifying nonresponders and to tailor treatment strategies.

Cinacalcet for secondary hyperparathyroidism in children with end-stage renal disease

The efficacy and acceptability of cinacalcet for treatment of secondary hyperparathyroidism (SHPT) was assessed in seven pediatric patients suffering from end-stage renal disease (ESRD) presenting with inadequately controlled SHPT despite conventional management. Patients received daily treatment with cinacalcet (dosage 0.25 mg/kg body weight) for a total of 4 weeks. Within 4 h after application of the first dose, median levels of serum parathyroid hormone (PTH) had decreased from 932 pg/ml (range 511-1,938 pg/ml) to 584 pg/ml (88-937 pg/ml), and final pre-dose values after 4 weeks were 199 pg/ml (121-940 pg/ml; each P < 0.05 versus baseline). Median concentrations of serum calcium (Ca) decreased within 4 h of the first administration, from 2.56 mmol/l to 2.38 mmol/l, returning to 2.58 mmol/l at 24 h, and they remained slightly decreased compared to baseline values thereafter (each P < 0.05 versus baseline). Both the median levels of serum phosphorus (P) and the Ca x P ion product decreased significantly during the 4-week period. Cinacalcet was well tolerated and without drug-related adverse effects. Thus, even with approximately half of the dose usually given to adult dialysis patients, PTH and the Ca x P ion product were markedly reduced in pediatric ESRD patients presenting with inadequately controlled SHPT. Therefore, our results support the initiation of a randomized, controlled, long-term trial in children.

Growth hormone treatment in short children with chronic kidney disease

Growth hormone (GH) has been used for treatment of impaired growth in children with chronic kidney disease (CKD) for nearly 17 years. Controlled and open-label studies have shown that GH is highly effective in improving growth velocity and adult height. The growth response is negatively correlated with age and height at start and time spent on dialysis treatment; it is positively correlated with dose and duration of treatment and the primary renal disease (renal hypodysplasia). In children with renal transplants, corticosteroid treatment is an additional factor negatively influencing spontaneous growth rates. However, GH treatment is able to compensate corticosteroid-induced growth failure. GH treatment improved final height by 0.5-1.7 standard deviation score (SDS) in various studies, whereas the control group lost about 0.5 SDS in comparable time intervals. These variable results are explained in part by the factors mentioned above. The adverse events are comparable to those in non-CKD children treated with GH.

CONCLUSION

GH treatment is safe and highly effective in improving growth and final height of short children with all stages of CKD. The highest treatment success is obtained if treatment is started at an early age and with relatively well-preserved residual renal function and continued until final height.

Factors predicting the near-final height in growth hormone-treated children and adolescents with chronic kidney disease

CONTEXT

GH therapy is an accepted measure to increase adult height in young prepubertal patients suffering from growth failure related to chronic kidney disease (CKD). The impact of GH therapy on final height (FH) in CKD patients of pubertal age is unclear.

OBJECTIVE

This study set out to analyze near-FH in a cohort of GH-treated CKD patients.

DESIGN, SETTINGS, AND PATIENTS

Of 240 evaluable patients in the Pfizer International Growth Database (KIGS) with CKD, 39% were prepubertal and 61% were pubertal at baseline; 45% were on conservative treatment for CKD, 28% were on dialysis, and 27% were in the period after renal transplantation.

MAIN OUTCOME MEASURES

Near-FH, relation to pubertal stage, and factors predictive of growth response were the main outcome measures.

RESULTS

Mean height sd scores increased continuously during GH treatment until near-FH by 1.2 and 1.6 in boys and girls, respectively. Mean near-FH differed significantly from prepubertal patients showing severely delayed puberty (-3.6), late pubertal patients (-2.9), early pubertal patients (-2.2), and prepubertal patients with normal onset of puberty (-2.0). The initial degree of stunting, degree of bone age retardation, duration of GH therapy, time spent on conservative treatment/dialysis, pubertal delay (>2 sd), gender, and age at start of GH treatment were significant predictors of growth response to GH therapy, explaining between 33 and 61% of the overall variability.

CONCLUSIONS

Long-term GH therapy of CKD patients in prepubertal and pubertal age results in an increased adult height, but response is diminished in patients on dialysis and/or with severely delayed puberty.

Linear growth in pediatric hemodialysis patients

Growth is an important outcome in pediatric kidney disease. We aimed to identify factors associated with growth in pediatric hemodialysis (HD) patients. Height standard deviation scores (Ht SDS) of pediatric HD patients with consecutive height measurements in the ESRD Clinical Performance Measures Project were calculated. Multiple linear regression determined the effect of factors on Ht SDS change/year. Four hundred and seven patients were included. Median age was 15.2 years (interquartile range 13.2-16.5 years); 44% were girls, and 27% were black. Of patients observed, 66% had growth hormone (GH) data, and of those, 29% were prescribed GH. Mean change in Ht SDS/year was -0.10+/-0.71. After adjustment, decreasing Ht SDS was associated with younger age (-0.2/year for <13 vs. >or=13 years; p<0.0001), longer duration on dialysis (-0.03/year for >or=6 months vs. <6 months; p<0.01), and higher normalized protein catabolic rate (nPCR) (-0.02/year per 0.1; p<0.05). Improved growth was seen in girls (0.10/year; p<0.01) and in those with lower Ht SDS (0.03/year per 0.5 decrease; p<0.001). Hemoglobin, GH use, and adequacy were associated with neither positive nor negative changes in Ht SDS. Growth retardation while on HD was most pronounced in patients who were young, male, had longer durations on HD, had higher nPCR, and had higher baseline Ht SDS.

Growth in children with chronic renal failure and after renal transplantation

Growth retardation is a major problem for many children with chronic renal failure (CRF) and transplantation. The aim of this study is to assess the relation between height, glomerular filtration rate (GFR), hormonal alterations in children with CRF on regular haemodialysis (HD), and the impact of functioning graft after kidney transplantation.Thirty-six hemodialysed children were included in the study beside 32 pediatric transplants. Mean duration on HD was 14.72 +/- 7.73 months for the CRF group, while the mean interval after transplantation was 1.97 +/- 0.9 years for the second group. Moreover, twenty healthy children of matched age and sex served as controls. Assessment of growth parameters included height, expressed as standard deviation scores (Ht SDS) for chronological age, serum levels of growth hormone (hGH), and parathormone (PTH). Growth performance was evaluated twice: at the start of the study and one year later. Children with CRF and transplantation had significantly higher levels of both serum hGH and PTH compared to their controls, while CRF children experienced significantly higher serum levels of both hGH and PTH compared to those with functioning graft. Furthermore, analysis of our results by non-parametric Kendall's correlation at the start and one year later revealed negative correlation concerning dialysis duration, serum creatinine, and PTH. On the other hand, positive correlation was achieved for serum calcium and GFR.

Growth hormone for children with chronic kidney disease

BACKGROUND

Chronic kidney disease (CKD) is an uncommon but important condition. Growth retardation, one of the complications of CKD, is of concern to families. Recombinant human growth hormone (rhGH) treatment has been used to help short children with CKD attain a height more in keeping with their age group. However, there are concerns that rhGH may have an adverse effect on the preservation of native kidney function, predispose to acute rejection in kidney transplant recipients, and cause benign intracranial hypertension and slipped capital femoral epiphysis.

OBJECTIVES

To evaluate the benefits and harms of rhGH treatment in children with CKD.

SEARCH STRATEGY

Randomised controlled trials (RCTs) were identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, article reference lists and through contact with local and international experts in the field. Date of most recent search: July 2005

SELECTION CRITERIA

RCTs were included if they were carried out in children aged 0-18 years, diagnosed with CKD, who were pre-dialysis, on dialysis or post-transplant; if they compared rhGH treatment with placebo/no treatment or two doses of rhGH treatments; and if they included height outcomes.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed studies for methodological quality and extracted data from eligible trials. Data was pooled using a random effects model with calculation of weighted mean difference (MD) for continuous outcomes and relative risk (RR) for categorical outcomes with 95% confidence intervals (CI).

MAIN RESULTS

Fifteen RCTs (629 children) were identified. Treatment with rhGH (28 IU/m(2)/wk) resulted in a significant increase in height standard deviation score (SDS) at one year (MD 0.78 SDS, 95% CI 0.52 to 1.04), and a significant increase in height velocity at six months (MD 2.85 cm/6 mo, 95%CI 2.22 to 3.48) and one year (MD 3.80 cm/y, 95%CI 3.20 to 4.39). Compared to the 14 IU/m(2)/wk group, there was a 1.34 cm/y (0.55 to 2.13) increase in height velocity in the 28 IU/m(2)/wk group. The frequency of reported side effects of rhGH were similar to that of the control group.

AUTHORS' CONCLUSIONS

One year of 28 IU/m(2)/wk rhGH in children with CKD resulted in a 3.80 cm/y increase in height velocity above that of untreated patients. Trials were too short to determine if continuing treatment resulted in an increase in final adult height.

Assessment and treatment of short stature in pediatric patients with chronic kidney disease: a consensus statement

Growth failure is a clinically important issue in children with chronic kidney disease (CKD) and is associated with significant morbidity and mortality. Many factors contribute to impaired growth in these children, including abnormalities in the growth hormone (GH)-insulin-like growth factor-I (IGF-I) axis, malnutrition, acidosis, and renal bone disease. The management of growth failure in children with CKD is complicated by the presence of other disease-related complications requiring medical intervention. Despite evidence of GH efficacy and safety in this population, some practitioners and families have been reluctant to institute GH therapy, citing an unwillingness to comply with daily injections, reimbursement difficulties, or impending renal transplantation. Suboptimal attention to growth failure management may be further compounded by a lack of clinical guidelines for the appropriate assessment and treatment of growth failure in these children. This review of growth failure in children with CKD concludes with an algorithm developed by members of the consensus committee, outlining their recommendations for appropriate steps to improve growth and overall health outcomes in children with CKD.

Growth hormone/insulin-like growth factor system in children with chronic renal failure

Disturbances of the somatotropic hormone axis play an important pathogenic role in growth retardation and catabolism in children with chronic renal failure (CRF). The apparent discrepancy between normal or elevated growth hormone (GH) levels and diminished longitudinal growth in CRF has led to the concept of GH insensitivity, which is caused by multiple alterations in the distal components of the somatotropic hormone axis. Serum levels of IGF-I and IGF-II are normal in preterminal CRF, while in end-stage renal disease (ESRD) IGF-I levels are slightly decreased and IGF-II levels slightly increased. In view of the prevailing elevated GH levels in ESRD, these serum IGF-I levels appear inadequately low. Indeed, there is both clinical and experimental evidence for decreased hepatic production of IGF-I in CRF. This hepatic insensitivity to the action of GH may be partly the consequence of reduced GH receptor expression in liver tissue and partly a consequence of disturbed GH receptor signaling. The actions and metabolism of IGFs are modulated by specific high-affinity IGFBPs. CRF serum has an IGF-binding capacity that is increased by seven- to tenfold, leading to decreased IGF bioactivity of CRF serum despite normal total IGF levels. Serum levels of intact IGFBP-1, -2, -4, -6 and low molecular weight fragments of IGFBP-3 are elevated in CRF serum in relation to the degree of renal dysfunction, whereas serum levels of intact IGFBP-3 are normal. Levels of immunoreactive IGFBP-5 are not altered in CRF serum, but the majority of IGFBP-5 is fragmented. Decreased renal filtration and increased hepatic production of IGFBP-1 and -2 both contribute to high levels of serum IGFBP. Experimental and clinical evidence suggests that these excessive high-affinity IGFBPs in CRF serum inhibit IGF action in growth plate chondrocytes by competition with the type 1 IGF receptor for IGF binding. These data indicate that growth failure in CRF is mainly due to functional IGF deficiency. Combined therapy with rhGH and rhIGF-I is therefore a logical approach.

Daily or intermittent calcitriol administration during growth hormone therapy in rats with renal failure and advanced secondary hyperparathyroidism

Growth hormone (GH) improves growth in children with chronic renal failure. The response to GH may be affected by the degree of secondary hyperparathyroidism and concurrent treatment with vitamin D. Forty-six rats underwent 5/6 nephrectomy (Nx) and were given a high-phosphorus diet (Nx-Phos) to induce advanced secondary hyperparathyroidism and divided into the following groups: (1) Nx-Phos (n = 10) received saline, (2) GH at 10 IU/kg per d (Nx-Phos+GH; n = 9), (3) GH and daily calcitriol (D) at 50 ng/kg per d (Nx-Phos+GH+daily D; n = 8), (4) GH and intermittent D (three times weekly) at 350 ng/kg per wk (Nx-Phos+GH+int D; n = 9), and (5) intact-control (n = 10). Serum parathyroid hormone (PTH) levels were elevated in Nx-Phos, but IGF-I levels did not change with growth hormone. Body length, tibial length, and growth plate width did not increase with either GH or calcitriol. Proliferating cell nuclear antigen staining, PTH/PTHrP receptor, bone morphogenetic protein-7, and fibroblast growth factor receptor-3 expression increased with GH alone or with intermittent calcitriol but were slightly diminished during daily calcitriol administration. GH enhanced IGF-I, IGF binding receptor-3, and GH receptor but declined with daily and intermittent calcitriol. Overall, there was no improvement in body length, tibial length, and growth plate width at the end of GH therapy, but selected markers of chondrocyte proliferation and chondrocyte differentiation increased, although these changes were attenuated by calcitriol. The combination of GH and calcitriol that is frequently used in children with renal failure and secondary hyperparathyroidism require further studies to evaluate the optimal dose and frequency of administration to increase linear growth and prevent bone disease.

Bone elongation in rats with renal failure and mild or advanced secondary hyperparathyroidism

BACKGROUND

Impairment of growth in children with chronic renal failure may be due, in part to the insensitivity to the actions of growth hormone by insulin-like growth factor-I (IGF-I) because of accumulations of IGF binding proteins. There are a few studies describing the changes that occur in the growth plate in renal failure. None of these studies has simultaneously compared the modifications in the expression of selected markers of endochondral bone formation in renal failure with mild or advanced secondary hyperparathyroidism.

METHODS

Forty-six rats that underwent 5/6 nephrectomy (Nx) were fed either standard rodent diet (Nx-control) or high phosphorus diet to induce advanced secondary hyperparathyroidism (Nx-phosphorus) for 4 weeks. Sections of the tibia were obtained for growth plate histomorphometry, immunohistochemistry studies, and in situ hybridization experiments for selected markers of endochondral bone formation.

RESULTS

Weight gain, gain in length, and tibial length were less in Nx animals. Serum parathyroid hormone (PTH) and phosphorus levels were higher and serum calcium levels were lower in the Nx-phosphorus group. The width of the growth plate was much shorter in the Nx-phosphorus group due to a decrease in both proliferative and hypertrophic zones. IGF-I protein and IGF binding protein-3 staining were diminished in both Nx groups without changes in the IGF-I receptor expression; the decline in IGF-I protein expression was much lower in the Nx-phosphorus group. PTH/PTH receptor protein (PTHrP) receptor mRNA transcripts decline and tartrate-resistant acid phosphastase (TRAP) staining increased only in the Nx-phosphorus group.

CONCLUSION

The growth impairment in renal failure may be worsened by the severity of secondary hyperparathyroidism.

Growth hormone treatment in children: review of safety and efficacy

Since the advent of growth hormone (GH), the pediatric applications of GH therapy have expanded. Children with a wide variety of growth disorders have received GH treatment. The therapeutic effects and safety profile of GH in a number of pediatric conditions are reviewed, including GH deficiency (GHD), Turner syndrome, chronic renal failure, children born small for gestational age, Prader-Willi syndrome, juvenile chronic arthritis, and cystic fibrosis. GH therapy has been clearly shown to improve height velocity during childhood in a variety of pediatric conditions in which growth is compromised. There is now data that confirms GH treatment also improves final height in a number of diagnostic subgroups. Early initiation and individualization of GH treatment has the potential to normalize childhood growth in children with idiopathic GHD and enable them to achieve their genetic target height in a cost-effective manner. In children in whom GHD is not the main factor compromising growth, supra-physiological doses of GH have been shown to increase height velocity during childhood and final height. The development of predictive models for these conditions may allow further improvements in height outcome while maintaining an acceptable safety profile. Survivors of childhood malignancy, particularly those who have had craniospinal irradiation, represent a particularly challenging group. They appear to be less responsive to GH than children with idiopathic GHD and have a tendency to enter puberty at an earlier age. Both of these factors have a negative impact on their final height. Strategies that combine GH treatment with suppression of puberty using a gonadotropin releasing hormone analog may result in improved height outcomes. When children with GHD are treated with standard doses of GH there is a strong safety record. Adverse events during GH therapy are uncommon and often not drug related. Continued surveillance into adult life is crucial however, particularly in children receiving supra-physiological doses of GH or whose underlying condition increases their risk of adverse effects.

Growth hormone therapy in calcium-loaded rats with renal failure

GH increases linear growth in children with chronic renal failure, but the response remains suboptimal in some patients. Some of the factors that may explain the poor response to GH include high doses of calcitriol and exogenous calcium loading to prevent hyperphosphatemia. High doses of exogenous calcium adversely affect chondrocyte proliferation and delay mineralization in the growth plate of rats with renal failure; bone histomorphometric changes in these animals are comparable to adynamic bone. To evaluate GH effects on adynamic bone in renal failure, 48 weanling rats underwent sham nephrectomy (Intact-Control) or 5/6 nephrectomy (Nx). Nx animals were fed a high-calcium diet (Nx-Ca(2+)) to induce adynamic bone. After 4 wk, the Nx-Ca(2+) animals were treated with GH (Nx-Ca(2+) + GH), calcitriol (Nx-Ca(2+) + D), or a combination of GH and calcitriol (Nx-Ca(2+)GH + D) for 2 wk. Serum intact PTH and IGF-I levels did not differ among all nephrectomized groups given high calcium. GH did not increase body length or tibial length at the end of study period. In the proximal tibia, the width of the growth plate and the growth plate architecture did not improve with GH. There was a decline in histone-4 expression, IGF-I protein, IGF binding protein-3, and bone morphogenetic protein-7 staining and a mild increase in IGF-I receptor, GH receptor, and gelatinase B expression in the Nx-Ca(2+) + GH group when compared with the Intact-Control group. Calcitriol blunted some of the mitogenic effects of GH in the growth plate. Thus, there was a poor response to GH therapy in calcium-loaded animals with renal failure.

Special aspects of renal osteodystrophy in children

Renal osteodystrophy represents a spectrum of skeletal lesions that range from high-turnover to low-turnover bone disease. Similar factors are involved in the pathogenesis of renal osteodystrophy in adult and pediatric patients with chronic kidney disease (CKD). However, growth retardation and the development of bone deformities are specific complications that occurred in pediatric patients with CKD. Metabolic acidosis, renal osteodystrophy, malnutrition, and disturbances in the insulin growth factor (IGF)/growth hormone (GH) are among the main factors involved and they are discussed briefly in this article. In addition to disturbances in bone remodeling, longitudinal bone growth occurs at the growth plate cartilage by endochondral ossification. Although young rats with experimental CKD have growth retardation, the characteristics of the growth plate are markedly different between animals with severe secondary hyperparathyroidism and those with calcium-induced adynamic osteodystrophy. These disturbances may suggest potential molecular mechanisms by which endochondral bone formation may be altered in renal failure, consequently leading to growth retardation.

Peritoneal dialysis in children: challenges for the new millennium

Advances in technology and experience accumulated over the past 2 decades have resulted in the ability to successfully provide chronic peritoneal dialysis (PD) to children of all ages and sizes. However, many important clinical issues remain, including uncertainty regarding the "optimal" dialysis dose for children, the treatment of growth retardation associated with renal insufficiency, prevention of peritonitis, and the challenge of caring for newborn infants with end-stage renal disease (ESRD). This article summarizes current knowledge in each of these 4 areas, highlighting not only the advances of the past quarter-century, but also the questions that persist as we initiate the new millennium. The outcome of children receiving PD will be markedly improved only when ongoing and future research efforts reveal the optimal solutions to these important issues.

Effect of growth hormone treatment on the adult height of children with chronic renal failure. German Study Group for Growth Hormone Treatment in Chronic Renal Failure

BACKGROUND

Growth hormone treatment stimulates growth in short children with chronic renal failure. However, the extent to which this therapy increases final adult height is not known.

METHODS

We followed 38 initially prepubertal children with chronic renal failure treated with growth hormone for a mean of 5.3 years until they reached their final adult height. The mean (+/-SD) age at the start of treatment was 10.4+/-2.2 years, the mean bone age was 7.1+/-2.3 years, and the mean height was 3.1+/-1.2 SD below normal. Fifty matched children with chronic renal failure who were not treated with growth hormone served as controls.

RESULTS

The children treated with growth hormone had sustained catch-up growth, whereas the control children had progressive growth failure. The mean final height of the growth hormone-treated children was 165 cm for boys and 156 cm for girls. The mean final adult height of the growth hormone-treated children was 1.6+/-1.2 SD below normal, which was 1.4 SD above their standardized height at base line (P< 0.001). In contrast, the final height of the untreated children (2.1+/-1.2 SD below normal) was 0.6 SD below their standardized height at base line (P<0.001). Although prepubertal bone maturation was accelerated in growth hormone-treated children, treatment was not associated with a shortening of the pubertal growth spurt. The total height gain was positively associated with the initial target-height deficit and the duration of growth hormone therapy and was negatively associated with the percentage of the observation period spent receiving dialysis treatment.

CONCLUSIONS

Long-term growth hormone treatment of children with chronic renal failure induces persistent catch-up growth, and the majority of patients achieve normal adult height.

[Critical evaluation of growth hormone treatment in children with chronic renal insufficiency]

Growth failure remains a major complication of chronic renal insufficiency in children, which greatly affects their quality of life. Based upon the data published in the literature it appears that growth hormone therapy improves growth in these children, with little secondary effects. However, some uncertainties persist concerning the safety and efficacy of this therapy, so that careful evaluations must continue.

[Children with chronic renal failure: evaluation of the nutritional status and management]

Since malnutrition is a well recognized problem in children with chronic renal failure, nutritional management of these children is essential. This review describes methods for nutritional assessment and suggests guidelines for providing maximal dietary support in children with chronic renal insufficiency. Optimal nutritional management includes an adequate caloric and protein intake, a restriction of phosphorus intake and an appropriate intake of electrolytes and vitamins.

Growth retardation in children with chronic renal failure

Growth retardation is a major obstacle to full rehabilitation of children with chronic renal failure (CRF). Several factors have been identified as contributors to impaired linear growth and they include protein and calorie malnutrition, metabolic acidosis, growth hormone resistance, anemia, and renal osteodystrophy. Although therapeutic interventions such as the use of recombinant human growth hormone, recombinant human erythropoietin, and calcitriol have made substantial contributions, the optimal therapeutic strategy remains to be defined. Indeed, growth failure persists in a substantial proportion of children with renal failure and those treated with maintenance dialysis. In addition, the increasing prevalence of adynamic lesions of renal osteodystrophy and its effect on growth have raised concern about the continued generalized use of calcitriol in children with CRF. Recent studies have shown the critical roles of parathyroid hormone-related protein (PTHrP) and the PTH/PTHrP receptor in the regulation of endochondral bone formation. The PTH/PTHrP receptor mRNA expression has been shown to be down-regulated in kidney and growth plate cartilage of animals with renal failure. Differences in the severity of secondary hyperparathyroidism influence not only growth plate morphology but also the expression of selected markers of chondrocyte proliferation and differentiation in these animals. Such findings suggest potential molecular mechanisms by which cartilage and bone development may be disrupted in children with CRF, thereby contributing to diminished linear growth.

Growth during maintenance hemodialysis: impact of enhanced nutrition and clearance

Growth of children during maintenance hemodialysis has been reported to be uniformly poor, with a mean annual loss of 0.4 to 0.8 SD in height. We adopted an intensive program of closely monitored energy and protein intake with dialysis urea clearances exceeding conventional recommendations. Twelve prepubertal or early pubertal children (aged 7 months to 14 years) were monitored for an average of 2.2 years (range 4 to 81 months) while receiving maintenance hemodialysis. These children received an average of 90.6% and 155.9% of their recommended energy and protein nutritional intake, respectively. With a prescribed urea clearance of 5 mL/kg/min, we achieved a mean single treatment urea clearance normalized for total body water of 2.00, a urea reduction ratio of 84.7%, and an average time of hemodialysis of 14.8 h/wk, all well beyond current guidelines. Over the course of dialysis treatment, the improvement in height SD score was+0.31 SD/y (+0.32 excluding the 2 children treated with recombinant human growth hormone). Normal growth was achieved without overt obesity and was associated with normal pubertal growth spurt. These findings suggest that the combination of increased dialysis and adequate nutrition can promote normal growth in children treated with long-term hemodialysis.

Growth in renal failure: a longitudinal study of emotional and behavioural changes during trials of growth hormone treatment

Growth and psychological functioning were studied in 30 patients with renal failure over a two year period following the offer of growth hormone treatment for significant short stature. Parents' concerns about growth decreased significantly during the study. Twenty eight parents (93%) accepted growth hormone treatment; most (74%) were satisfied with it and would opt for it again (89%). The views of these parents were unrelated to growth outcome in their child. This suggests that the positive responses were related more to the effort to improve growth than to any objective treatment success. In contrast children's reduction in concern about growth, satisfaction with treatment (36%), and decision to opt for growth hormone again (50%) were all significantly related to improvement in growth. Parents' reports of non-compliance increased significantly from 41% at 1 year to 91% at 2 years in the group as a whole. No significant changes were identified in maternal mental distress and no additional costs to the psychological health of the children seem to have resulted from the introduction of growth hormone treatment. A group of children was identified who accepted treatment but had continued poor growth. These appeared to be at particular risk of both physical problems and associated or consequent psychological difficulties.

Growth hormone treatment of children with chronic renal insufficiency, end-stage renal disease and following renal transplantation--update 1997

1. Long-term (> 5 years) hGH treatment in children with CRI produces sustained improvement in standardized height. 2. hGH treatment of infants (< 2 1/2 years of age) with CRI is as effective at improving growth velocity as in older children with CRI. 3. Once target height (50th percentile for midparental height) is reached the optimal approach is to pause hGH treatment and observe the patient. If standardized height declines significantly, hGH is effective when re-initiated. 4. Neither short-term nor long-term hGH treatment in children with CRI or in pediatric allograft recipients adversely impacts on carbohydrate tolerance; however, hyperinsulinemia develops which has not been associated with any clinical consequences to date. 5. The presence of renal osteodystrophy may blunt the impact of hGH and predispose to development of slipped capital femoral epiphysis and/or avascular necrosis in children with CRI. Pre-treatment radiologic evaluation and radiologic surveillance with clinical symptoms is indicated. 6. hGH is effective during the initial year of treatment; however the response may be blunted during subsequent years of treatment. The precise mechanism of the latter has not been delineated. 7. hGH has been shown to improve growth velocity in patients undergoing both peritoneal and hemodialysis; however, long-term data are lacking and the response may be less than that achieved in patients with CRI. 8. Growth velocity is uniformly improved in growth retarded pediatric renal allograft recipients receiving hGH. 9. Allograft dysfunction occurs following hGH treatment; however, the relationship to hGH treatment requires delineation. 10. The mechanism responsible for early allograft dysfunction which is usually reversible upon discontinuation of hGH is unknown. 11. Risk factors for the development of an acute rejection episode during the course of hGH treatment are > 1 prior rejection episode and the use of alternate day corticosteroid therapy. 12. The potential exists for an accelerated decline in allograft function following hGH treatment in recipients with chronic rejection. 13. The salutary effect of hGH in this patient population is probably related to increasing the bioavailability of ("free") IGF-I.

Factors influencing the response to growth hormone in children with renal disease

The effects of age, height velocity over the preceding year, glomerular filtration rate (GFR) and prednisolone dose on growth response have been assessed by single and multiple linear regression analysis in 23 prepubertal children [age, mean (SD), 8.2 (2.5) years] with chronic renal failure (CRF) and 16 prepubertal children [12.1 (2.3) years] with renal transplants treated for 1 year with recombinant human growth hormone (rhGH), 30 U/m2 per week. Height velocity [mean (SD), cm/year] increased from 4.7 (1.3) to 9.7 (2.1) (P < 0.0001) in the CRF group and 3.1 (1.6) to 7.3 (2.8) (P < 0.0001) in the transplant group. In the CRF group, there was a correlation between age and height velocity, both in the pretreatment year (r = -0.755, P < 0.0001) and during treatment (r = -0.421, P = 0.045). There was no correlation between pretreatment height velocity or GFR and response to rhGH. In the transplanted children height velocity during the treatment year correlated with age (r = -0.647, P = 0.007), prednisolone dose (r = -0.689, P = 0.003), GFR (r = 0.542, P = 0.030) and pretreatment height velocity (r = 0.655, P = 0.006). Multiple regression analysis showed prednisolone dose and age to be the most important predictors of response.