Relationship of type I procollagen to corticosteroid therapy in children with inflammatory bowel disease

Bone Turnover Markers in Children: From Laboratory Challenges to Clinical Interpretation

Bone turnover markers (BTMs) have been developed many years ago to study, in combination with imaging techniques, bone remodeling in adults. In children and adolescents, bone metabolism differs from adults since it implies both growth and bone remodeling, suggesting an age- and gender-dependent BTM concentration. Therefore, specific studies have evaluated BTMs in not only physiological but also pathological conditions. However, in pediatrics, the use of BTMs in clinical practice is still limited due to these many children-related specificities. This review will discuss about physiological levels of BTMs as well as their modifications under pathological conditions in children and adolescents. A focus is also given on analytical and clinical challenges that restrain BTM usefulness in pediatrics.

Can we change the natural history of Crohn's disease with early immunomodulation?

In both children and adults, the natural history of Crohn's disease (CD) is characterized by relapsing and remitting bouts of intestinal inflammation, often associated with a progressive shift from inflammatory to complicated stricturing or penetrating disease behavior. The past 2 decades have seen a dramatic shift in therapeutic approach with the increasingly common use of early thiopurine immunomodulation. These maintenance medications were initially introduced primarily as corticosteroid-sparing agents capable of minimizing recurrent flares of inflammatory disease and have proven to be quite efficacious. Increasing evidence suggests, however, that thiopurines may only delay rather than prevent the development of complicated disease behavior. Data from both adult and pediatric CD populations from around the world are reviewed in terms of the effect of early immunomodulation on progression to complicated disease behavior, need for surgery, and prevention of recurrent disease after resection. The effect of thiopurines on the growth of children is also reviewed.

Update in pediatric inflammatory bowel disease

The incidence of inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis, in children is on the rise. Pediatric patients with IBD are especially vulnerable to the physical and psychosocial morbidities of this disorder. Unique aspects of pediatric IBD patients compared to adult patients warrants an individualized approach to management regardless of age. This review focuses on the special aspects of pediatric IBD and the implications for the diagnosis and management of this disease.

Surgery in children with Crohn disease refractory to medical therapy

OBJECTIVE

The aim of this study was to evaluate the results of surgery in children with Crohn disease (CD) not responding to medical therapy and establish whether surgery improves growth and nutrition.

PATIENTS AND METHODS

Children with CD diagnosed between 1998 and 2008 were reviewed. Relapse was defined by Harvey-Bradshaw index >5. Data, reported as median (range), were compared by Fisher exact test and repeated-measures ANOVA.

RESULTS

One hundred forty-one children, ages 12.7 years (3.5-16.8), were identified; 27 (19%) required surgery 14.5 months (1.1-61.8) after diagnosis. Twenty-one had elective surgery (19 isolated ileocaecal disease and stricture, 2 diffuse disease of ileum); 6 had emergency surgery (3 peritonitis, 2 haemorrhage, 1 perforation). Surgery included 18 ileocaecal resection and end-to-end anastomosis, 5 stoma formation, 2 left hemicolectomy and end-to-end anastomosis, and 2 stricturoplasty. Follow-up was 2.5 years (1-9.4). Growth and nutrition improved by 6 and 12 months after surgery, with a significant increase in weight z score (P < 0.0001), height z score (P < 0.0001), albumin (30 [13-36] vs 39 [30-46] vs 40 [33-45], P < 0.0001), and haemoglobin [10 (6.8-13.2) vs 11.7 (8.2-13.7) vs 12.0 (9.3-14.7), P < 0.0001]. All patients of the received azathioprine (2-2.5 mg · kg⁻¹ · day⁻¹) after surgery. Fifteen patients (55%) relapsed with a modified Harvey-Bradshaw index of 8 (6-11) within 11.5 months (4.2-33.4). Of these, 5 patients (18%) relapsed within 1 year. Five patients (18%) had further surgery (2 anastomotic strictures, 2 diseased stoma, and 1 enterocutaneous fistula).

CONCLUSIONS

Growth and nutrition following surgery for CD improve, but there is a high relapse rate. Despite this, the improved growth and nutrition before relapse may be beneficial during puberty and justify surgery in children not responding to medications.

Growth abnormalities persist in newly diagnosed children with crohn disease despite current treatment paradigms

OBJECTIVES

We analyzed growth outcomes in children newly diagnosed with Crohn disease and determined whether growth abnormalities persist despite current therapies.

PATIENTS AND METHODS

Clinical and growth data were prospectively obtained on an inception cohort younger than 16 years old at diagnosis and Tanner I to III during the study.

RESULTS

In all, 176 children (mean age 10.1 years; 65% male) with mild (33%) or moderate/severe (67%) disease at diagnosis were studied. Disease activity at 1 year was inactive/mild (89%) or moderate/severe (11%). First-year treatments included immunomodulators (60%), corticosteroids (77%), 5-aminosalicylates (61%), infliximab (15%), and enteral nutrition (10%). By 2 years, 86% had received immunomodulators and 36% infliximab. Mean height z scores at diagnosis, 1 year, and 2 years were -0.49 +/- 1.2 standard deviations (SDs), -0.50 +/- 1.2, and -0.46 +/- 1.1, respectively. Of the subjects, 10%, 8%, and 6.5% had height z scores less than -2 SD at diagnosis, 1 year, and 2 years. A height velocity z score less than -1SD was seen in 45% of subjects at 1 year and 38% at 2 years. The mean height velocity z score, however, increased between 1 and 2 years from -0.71 to 0.26 (P < 0.03). Corticosteroid use greater than 6 months in the first year was associated with abnormal height velocity at 1 year (adjusted odds ratio = 4.5; 95% confidence interval [CI] = 2.2-9.6). No statistically significant effect on height velocity z scores was noted when comparing those receiving or not receiving infliximab.

CONCLUSIONS

Growth delay persists in many children with CD following diagnosis, despite improved disease activity and the frequent use of immunomodulators and biologics. Additional strategies to improve growth outcomes require development.

Diagnosis and management of inflammatory bowel disease in children

Upwards of 100,000 children and adolescents are affected by inflammatory bowel disease (IBD) in the United States, and the incidence of IBD appears to be increasing worldwide. Although the diagnosis and differentiation of Crohn's disease or ulcerative colitis is still based on clinical, radiographic, endoscopic, and histological findings, newer less invasive serological tests are being employed to help distinguish these disorders and provide prognostic information to possibly guide therapy. Videocapsule endoscopy has increased our ability to detect previously unrecognized small bowel inflammation in selected patients. Whereas initial therapy has historically included aminosalicylates and corticosteroids, recent data suggest the limited efficacy of aminosalicylates in Crohn's disease and the high likelihood or corticosteroid dependence in patients with either Crohn's disease or ulcerative colitis. The early use of immunomodulators has become standard-of-care in both disorders and has decreased corticosteroid dependence. The advent of biologic therapy, primarily with infliximab, has dramatically improved short-term outcomes in both Crohn's disease and ulcerative colitis. Longer-term data on whether infliximab changes the natural history of these disorders (eg, requirement for surgery) awaits further study. As more aggressive therapy is being increasingly employed, rare complications such as lymphoma or opportunistic infection have developed.

Crohn's jejunoileitis: the pediatrician's perspective on diagnosis and management

Although uncommon, diffuse jejunoilietis is one of the most difficult areas in Crohn's disease (CD) to treat. Although the exact frequency is unknown, most gastroenterologists believe that its prevalence has been underestimated and that it may have an increased incidence among children and young adolescents. The clinical importance of this clinical disease phenotype is the impact diffuse small bowel disease is expected to have on a child's growth and development. Moreover, patients with jejunoileitis are more likely to experience complications, including fistulization, and most commonly, intestinal obstruction. The associated morbidity and frequent need for surgical intervention renders these patients at risk for intestinal insufficiency. Although stricturoplasty has reduced the incidence of short bowel syndrome, most patients with proximal small bowel CD still require repeated surgical intervention. Jejunoileitis represents a distinct clinical phenotype within the heterogenous family of disease phenotypes considered as CD. Whether a specific genotype will be found to associate with jejunoileitis remains to be determined. Through the development of novel diagnostic techniques, including gadolinium enhanced magnetic resonance imaging (GMRI), enteroscopy, and capsule endoscopy, the mean age at diagnosis is expected to decrease. Coupled with an increase in clinical suspicion, early diagnosis may allow physicians to consider implementing aggressive immunomodulatory therapy. Future studies are needed to determine if the early detection and use of immune modulators in patients with proximal small bowel disease will improve overall quality of life and decrease the risk of nutritional and surgical comorbidity.

Can we alter the natural history of Crohn disease in children?

The natural history of Crohn disease is characterized by recurrent bouts of active disease, the consequences of which can severely impair sufferers' physical and social functioning. Not only does the illness cause day-to-day morbidity for children but the consequence of the chronic inflammatory process also commonly results in the need for major intestinal surgery. The present challenge facing physicians treating children with Crohn disease is to alleviate symptoms and prolong periods of remission via the use of specifically targeted therapies while minimizing toxicity and promoting normal growth and development. Although systemic corticosteroids are effective in inducing clinical remission, they are of little or no benefit in maintaining remission and can contribute to linear growth retardation. Immunomodulating drugs such as azathioprine, 6-mercaptopurine and methotrexate have proved effective for inducing and maintaining remission of active Crohn disease. These agents are now commonly prescribed in children at diagnosis, after a severe attack or after surgery or in those who become corticosteroid-dependent or corticosteroid-resistant. Their use is not without potential adverse effects and not all patients respond well to these agents. With the introduction of biologic agents, notably the tumor necrosis factor-alpha monoclonal antibody infliximab, progress has been made in targeting specific pathogenetic mechanisms of Crohn disease and potentially altering the underlying disease process. Published experience in children is currently limited, but infliximab has been shown to improve symptoms and achieve corticosteroid independence in this age group. Unresolved issues with infliximab and other emerging biologic agents, including long-term safety, necessitate a degree of caution in selecting appropriate patients for treatment and with careful monitoring of their effects. The collection of contemporary natural history data is crucial to facilitate the better integration of current and emerging therapies in an attempt to alter the natural history of Crohn disease in children.

A review of activity indices and end points for clinical trials in children with Crohn's disease

The necessity to include children and adolescents in clinical trials is increasingly recognized. Two recent workshops provided the impetus for pediatric gastroenterologists to develop evidence-based recommendations concerning end points and outcome assessment in cases of pediatric Crohn's disease. The overall goal was to facilitate clinical trial design by standardizing the methodology. This article critically reviews the available assessment tools and provides consensus recommendations for the evaluation of linear growth, disease activity, and health-related quality of life in clinical trials in pediatric Crohn's disease.

Targeting therapy in pediatric inflammatory bowel disease

Progress in our understanding of the interaction between the environment and the immune system in disease pathogenesis has led to major advancements in the area of inflammatory bowel disease (IBD) therapeutics. Biotechnology is keeping pace with these scientific advances. Current therapies target the various elements of the inflammatory cascade implicated in the pathogenesis of IBD. The anti-inflammatory and immunomodulatory properties of the pharmacologic therapies used in IBD vary from actions that are extremely broad to those that are cellular or cytokine specific. Despite the various therapeutic options available for IBD patients, chosen therapies should be based on the overall treatment goal for individual patients. Therapeutics can be broadly categorized as induction therapies (goal to treat active disease) and maintenance therapies (goal to prevent relapse of disease). The modern thinking behind drug development is that IBD therapy should be disease modifying so to avoid complications and alter the long term natural history of disease. This review will cover both current and emerging agents and highlight the pathogenesis of IBD and how it relates to therapeutic targets.

Growth hormone therapy before and after pediatric renal transplant

Children undergoing successful renal transplantation anticipate optimal growth and development. The use of rhGH pre- and post-Tx has been evaluated and supported by randomized control trials. Several strategies are required to maximize the potential benefit of this treatment in the renal population including provision of adequate nutrition intake, following bone parameters with appropriate interventions, and strategies to reduce steroid therapy including utilization of alternate day steroid treatment. Studies are required to further assess the impact of rhGH on renal allograft function, rejection risk, and allograft ultrastructural changes.

GH therapy in juvenile chronic arthritis: results of a two-year controlled study on growth and bone

Disturbance of growth frequently occurs in children suffering from juvenile chronic arthritis (JCA). Recognition of growth impairment is important because reduced final height is one of the permanent consequences. The aim of this study was to evaluate the efficacy and safety of human GH (hGH) in growth-retarded prepubertal children with JCA. Thirty-five children were tested for GH deficiency (GHD) and randomly assigned to a study and an untreated control group; five were GH deficient and were part of the GHD group. All received glucocorticoids. The study group was treated with 1 IU/kg BW.wk hGH; the GHD group was given 0.5 IU. During 2 yr of hGH treatment growth velocity and height SD score increased compared with baseline values. There was a marked increase in growth velocity in the treated groups, but also some increase in the control group. Plasma levels of IGF-I and IGF-binding protein-3 increased with GH treatment. These results suggest that hGH might be useful in the treatment of growth impairment in JCA. GH may counteract the adverse effects of glucocorticoid therapy, but its effect is dependent on the disease activity. Long-term controlled studies are needed to determine the risks and benefits of GH therapy in JCA.

Controlled ileal release budesonide in pediatric Crohn disease: efficacy and effect on growth

BACKGROUND

Although the effectiveness of controlled ileal release (CIR) budesonide in children can be extrapolated from adult studies, there are currently no data available concerning the effects of CIR budesonide therapy on linear growth. In the absence of controlled, prospective pediatric clinical trials, we reviewed the outcomes, particularly linear growth, of children and adolescents given CIR budesonide to treat active intestinal inflammation and to maintain remission.

METHODS

Thirty-two children (20 males) aged 14.1 +/- 2.7 years with Crohn disease of the distal ileum with or without right colon involvement were treated for active Crohn disease (baseline Pediatric Crohn Disease Activity Index, 34 +/- 14) with 9 mg daily of CIR budesonide through the Hospital for Sick Children, University of Toronto, Inflammatory Bowel Diseases program.

RESULTS

At first follow-up visit 8.7 +/- 6.0 weeks later, 19 of 32 (59%) were judged by the physician to have responded. In the subset of 22 patients who had laboratory tests repeated at the first follow-up visit, their Pediatric Crohn Disease Activity Index fell from 33 +/- 14 to 22 +/- 16 (P = 0.001). The Pediatric Crohn Disease Activity Index score fell to less than 15 (cut-off score remission) in 29%. Six prepubertal responders continued to receive 6 mg CIR budesonide for 6 to 13 months. Five of the 6 experienced only mild or no gastrointestinal symptoms and gained weight. Nevertheless, their mean height velocity was only 2.3 +/- 1.0 cm/year, and none grew at a rate of more than 4cm/year whilst receiving CIR budesonide.

CONCLUSIONS

These data provide grade III evidence of modest effectiveness of CIR budesonide in children with active Crohn disease confined to the ileum with or without right colon involvement. The subnormal growth observed with continued therapy is concerning and may reflect either inadequately controlled intestinal inflammation or direct suppression of linear growth, as is observed with conventional corticosteroids. Randomized controlled pediatric trials of CIR budesonide must include parameters of linear growth as an outcome variable.

Corticosteroids in the treatment of gastrointestinal disease

Corticosteroids remain the mainstay of anti-inflammatory and immunosuppressive therapy for many gastrointestinal conditions. We are now starting to understand their mechanism of action and the phenomenon of corticosteroid resistance. Because of the ubiquity of corticosteroid receptors in virtually all cells of the body, side effects of therapy are common and may affect multiple body sites. Newer corticosteroid analogues are being developed to minimize these complications, and concomitant use of other immunomodulatory drugs often facilitates corticosteroid dosage reduction or even withdrawal in chronic inflammatory states.

A multicenter trial of 6-mercaptopurine and prednisone in children with newly diagnosed Crohn's disease

BACKGROUND & AIMS

Clinical experience suggests that 6-mercaptopurine (6-MP) is effective therapy for children with active steroid-dependent Crohn's disease (CD). We report the results of a prospective, placebo-controlled, multicenter trial evaluating the combination of 6-MP and prednisone as therapy for children with newly diagnosed moderate-to-severe CD.

METHODS

Fifty-five children (age, 13+/-2 years) were randomized to treatment with 6-MP (1.5 mg x kg(-1) x day(-1)) or placebo within 8 weeks of initial diagnosis. Both groups also received prednisone (40 mg/day). Prednisone dosage adjustments were based on a defined schedule determined by the change in a subject's disease activity score, and steroid administration was discontinued as remission was achieved. Study treatment with 6-MP or placebo continued for 18 months.

RESULTS

Groups were comparable for age, sex, and site and activity of disease. In the 6-MP group, the duration of steroid use was shorter (P<0.001) and the cumulative steroid dose lower at 6, 12, and 18 months (P<0.01). Although remission was induced in 89% of both groups, only 9% of the remitters in the 6-MP group relapsed compared with 47% of controls (P = 0.007). Growth was comparable in both groups. No clinically significant adverse events occurred, although mild leukopenia and increases in aminotransferase activity were noted in the 6-MP group.

CONCLUSIONS

Addition of 6-MP to a regimen of corticosteroids significantly lessens the need for prednisone and improves maintenance of remission. 6-MP should be part of the initial treatment regimen for children with newly diagnosed moderate-to-severe CD.

Short-term growth and collagen turnover in asthmatic adolescents treated with the inhaled glucocorticoid budesonide

Short-term lower leg growth, the insulin-like growth factor axis, and collagen turnover were assessed in 16 adolescents with asthma during treatment with inhaled budesonide, 800 micrograms/d, from a pressurized metered dose inhaler with a volume spacer. The design was a randomized double blind, placebo-controlled two-period crossover trial with treatment periods of 4 weeks and a 1-week wash-out. Lower leg growth was assessed by knemometry. Serum levels of insulin-like growth factor-I, insulin-like growth factor-binding protein-3, and the following markers of collagen turnover were evaluated: Serum markers of type I collagen formation and degradation; the carboxy-terminal propeptide of type I procollagen and the carboxy terminal pyridinoline cross-linked telopeptide of type I procollagen (ICTP), the serum marker of type III collagen formation; the amino-terminal propeptide of type III procollagen (PIIINP) and the urinary concentrations of the type I collagen degradation products pyridinoline (PYD) and deoxypyridinoline (DPD) cross-links. Mean lower leg growth velocity was suppressed from 0.51 mm/week during placebo to 0.18 mm/week during budesonide treatment (p < 0.001). No statistically significant effects on insulin-like growth factor-1, insulin-like growth faster-binding protein-3, or carboxy-terminal propeptide of type I procollagen were observed. ICTP and PIIINP were reduced with 2.3 and 2.5 micrograms/liter (p < 0.001 and p < 0.001, respectively) during budesonide treatment, urinary concentrations of PYD and DPD with 32.9 nmol/mmol creatinine (p < 0.005) and 6.8 nmol/mmol creatinine (p < 0.005), respectively. Significant correlations between lower leg growth velocity and ICTP, PIIINP, PYD, and DPD during placebo (p < 0.01, p < 0.05, p < 0.01, and p < 0.01) and budesonide (p < 0.05, p < 0.05, p < 0.05, and p < 0.05) periods were found. Short term lower leg growth suppression in adolescents treated with inhaled budesonide, 800 micrograms/d, reflects suppression of type I and III collagen turnover.

Knemometry, urine cortisol excretion, and measures of the insulin-like growth factor axis and collagen turnover in children treated with inhaled glucocorticosteroids

Correlations between knemometric (lower leg length) growth rates and urine free cortisol excretion, respectively, and serum concentrations of IGF-I, IGF binding protein-3, osteocalcin, carboxy terminal propeptide of type I collagen (PICP), carboxy terminal pryridinoline cross-linked telopeptide of type I procollagen (ICTP), and amino terminal propeptide of type III procollagen (PIIINP) were investigated in 17 asthmatic children aged 7-14 y during treatment with fluticasone propionate, 200 micrograms, and beclomethasone dipropionate, 400 and 800 micrograms/d, taken from dry powder inhalers. The study was a double blind, crossover trial with three active treatment periods and two wash-out periods. All periods were 15 d long. Overnight urine free cortisol/ creatinine x 10(6) did not correlate with knemometric growth rates or any of the serum markers. Significant correlations (Pearson's correlation coefficient, P) between knemometric growth rates and IGF-I (0.41; 0.006), IGFBP-3 (0.35; 0.02), PICP (0.44; 0.003), ICTP (0.35; 0.001), and PIIINP (0.46; 0.002) were found. Compared with fluticasone propionate, 200 micrograms, beclomethasone dipropionate, 400 and 800 micrograms, caused significant suppression of lower leg growth rate (F = 12.41; p = 0.002, and F = 23.30; p = 0.0001, respectively) and of urine free cortisol/creatinine x 10(6) (F = 10.52; p = 0.003, and F = 13.74; p = 0.001). Beclomethasone, 800 micrograms, caused suppression of PICP compared with fluticasone propionate, 200 micrograms (F = 8.31; p = 0.008), and beclomethasone, 400 micrograms (F = 7.53; p = 0.01). Both low (F = 6.82; p = 0.02) and high (F = 23.35; p = 0.0001) doses of beclomethasone were associated with reduced concentrations of ICTP, the high dose being the most suppressive (F = 4.42; p = 0.05). Beclomethasone 400 (F = 9.75; p = 0.004) and 800 micrograms (F = 23.61; p = 0.0001) resulted in reduced levels of PIIINP. Reduced short-term knemometric growth rates in children treated with inhaled glucocorticosteroids reflect suppressive effects on type I and type III collagen turnover.

Growth suppression by glucocorticoid therapy

Glucocorticoids exert multiple growth-suppressing effects, interfering with endocrine (e.g., endogenous GH secretion) and metabolic (e.g., bone formation, nitrogen retention, collagen formation) processes essential for normal growth. Relatively small oral doses of daily exogenous GC, alternate-day oral GC therapy, and even IC are capable of slowing growth in some children. These growth-inhibiting and catabolic effects of GC can be variably counterbalanced by GH therapy. With regard to linear growth, GH responsiveness depends on the GC dose and severity of underlying GC-dependent disease. Short-term risks of combined GH and GC therapy are low; longer term risks (e.g., reduced allograft function, survival, or both; increased underlying disease activity; oncologic risk) require further study. GH therapy in GC-dependent children remains experimental; children considered for such treatment should be enrolled in studies that facilitate careful monitoring and collective data analysis.

Crohn's disease in children

Crohn's disease is a chronic inflammatory condition that may affect any part of the gastrointestinal system and multiple extraintestinal organs. Although its exact pathogenesis remains unknown, increasing evidence suggests an abnormality in the control of "physiologic" inflammation caused by bacterial and other antigens. Diagnosis starts with a careful history and physical examination, and confirmation rests with radiologic and histologic studies. Newer treatments are more specifically targeting the cascade of cytokine-mediated events that perpetuate inflammation.

Pulse dexamethasone does not impair growth and body composition of very low birth weight infants

OBJECTIVE

Evaluation of repeated pulses of dexamethasone (PDEX), given to improve cardiopulmonary outcome, on growth of very low birth weight (VLBW, < 1500 g) infants.

METHODS

In this prospective, double-blind, randomized clinical trial, VLBW infants mechanically ventilated at 1 week of age received intravenous PDEX or saline placebo (P) for 3 days, every 10 days, until no supplemental oxygen or ventilation was required or 36 weeks postmenstrual age (PMA). Weight gain, fluid intake, caloric intake, and serum glucose were monitored throughout the study. Nutritional assessment at 36 weeks PMA consisted of weight, length, head circumference, skinfold thickness measures, body composition by total body electrical conductance, and bone mineral content (BMC) by single beam photon absorptiometry.

RESULTS

37 PDEX and 31 P infants survived at least 36 days and completed the protocol. Average daily weight gain, fluid intake and caloric intake were not different between groups. The pattern of weight gain (g/kg/day, mean +/- SD) was different: PDEX infants showed significant growth delay during (3.0 +/- 11.4) and immediately after (7.8 +/- 8.7) each pulse, with subsequent growth acceleration (18.3 +/- 8.2) until the next steroid pulse. In contrast, growth rate of P infants was constant (12.6 +/- 3.7) (p = 0.04). Hyperglycemia requiring insulin therapy occurred only in the PDEX group (10/37). The catch-up growth noted between pulses in the PDEX group was explained only in part by insulin therapy. At 36 weeks PMA, there were no differences between groups in body size, composition, or BMC.

CONCLUSION

PDEX negatively affected glucose metabolism and growth patterns during and immediately after drug exposure. However, assessment near term gestational age showed similar body composition and size in both groups.

The insulin-like growth factor axis and collagen turnover in asthmatic children treated with inhaled budesonide

Serum concentrations of growth hormone-dependent insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3), the carboxy terminal propeptide of type I procollagen (PICP), the carboxy terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP) and the amino terminal propeptide of type III procollagen (PIIINP) were studied in 14 prepubertal children with asthma (mean age 9.7 years) during treatment with inhaled budesonide. The study design was a randomized, crossover trial with two double-blind treatment periods (200 and 800 micrograms) and one open, non-randomized treatment period (400 micrograms). All periods were 18 days' duration. Budesonide treatment was associated with a dose-related suppressive trend in serum concentrations of PIIINP when the 400 micrograms period was included (p < 0.01; z = -2.7) and when it was excluded from the calculations (p < 0.01; z = -2.6), indicating reduced synthesis of type III collagen. A similar trend was observed in ICTP levels when the 400 micrograms period was excluded from the calculations (p = 0.05; z = -1.9). No other statistically significant variations were seen.

The insulin-like growth factor axis and collagen turnover during prednisolone treatment

Serum concentrations of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3), the carboxyterminal propeptide of type I collagen (PICP), the carboxyterminal pyridinoline crosslinked telopeptide of type I collagen (ICTP), and the aminoterminal propeptide of type III procollagen (PIIINP) were studied in 10 prepubertal children with asthma (mean age 9.0 years). The children were treated with 2.5 and 5.0 mg/day prednisolone in a randomised double blind crossover trial with run in, treatment, and washout periods of two weeks. No statistically significant effects on serum concentrations of IGF-I and IGFBP-3 were found. Dose related reductions of PICP, ICTP, and PIIINP were observed: the mean (SEM) reduction in PICP was 33.4 (26.3) and 68.4 (20.6) micrograms/l, in ICTP 2.5 (0.5) and 2.9 (0.6) micrograms/l, and in PIIINP 2.1 (0.7) and 3.1 (1.8) micrograms/l during the 2.5 and 5.0 mg prednisolone periods respectively. Short term treatment with low daily doses of prednisolone is associated with suppression of serum markers of type I and III collagen turnover in children with asthma. Intermediate and long term effects remain to be studied.

Growth and puberty in chronic inflammatory bowel disease

The consequences of IBD during childhood and adolescence may be devastating in terms of loss of growth potential, particularly if there has been a clinical course of frequent relapses resulting in inadequate nutrition and associated with repeated courses of steroid treatment. There is to date, however, a paucity of data recording final adult heights in such patients. The anticipation of relapse should become easier with increasing awareness of the importance of parameters of growth and pubertal development. Early and intensive nutritional support, and the use of steroid-sparing agents should help reduce the frequency and severity of any height deficit. The performance and timing of surgery must take into account the child's status in terms of height velocity and pubertal development. The importance of inducing the remission before the onset of puberty is stressed and this remission should be sustained at all costs during the pubertal years so that valuable height is not lost as a consequence of a missed pubertal growth spurt. Thus, increasing awareness of the issues of growth and development in these patients should improve the accuracy of initial diagnosis and early recognition of relapse, such that these children are ensured the best possible provision for achieving their full height potential.

Growth failure in children with inflammatory bowel disease: a prospective study

BACKGROUND

Growth failure frequently complicates the clinical course of inflammatory bowel disease (IBD) in children. This study was designed to investigate the role of disease activity versus steroid therapy on growth faltering in this disorder.

METHODS

We studied growth failure and its relationship to disease activity and steroid therapy in 69 children who have IBD by prospectively monitoring height for a maximum of 3 years. Disease activity and steroid use were recorded at entry into the study.

RESULTS

The prevalence of growth failure was 24%, 23%, and 39% by height velocity, Z score, and height-for-age criteria, respectively; deficits were equally prevalent regardless of the stage of pubertal development. A delay in linear growth persisted throughout puberty and was not reversed after surgery. Patients who had Crohn's disease were twice as likely to have growth abnormalities than patients who had ulcerative colitis. We detected significant negative associations between linear growth and disease activity but not steroid therapy.

CONCLUSIONS

In a unique group of children, growth failure is an early, "prepatterned" manifestation of IBD. The inflammatory process, rather than steroid use, has a predominant influence on the development of growth faltering.

Comparison of collagen propeptides as growth markers in children with inflammatory bowel disease

The serum concentrations of the carboxy-terminal propeptide of type I procollagen and the amino-terminal propeptide of type III procollagen as biochemical markers of growth activity were compared in 46 children and adolescents with inflammatory bowel disease. Significant correlations were noted between growth velocity and type I procollagen (r = 0.65; P less than 0.001) and type III procollagen concentrations (r = 0.64; P less than 0.001). Although the serum concentration of type I procollagen was generally about 15 times greater than that of type III, the respective serum concentrations were highly correlated (r = 0.66; P less than 0.001) at all growth velocities. The use of daily corticosteroid therapy was associated with significantly lower concentrations of both propeptides (P less than 0.01) than was alternate-day or no corticosteroid therapy, respectively. Children with growth arrest (0.0 cm/mo) had type I and type III procollagen concentrations similar to those found in adults. These observations indicate that the serum concentrations of both collagen propeptides reflect growth activity in children with inflammatory bowel disease and suggest that routine measurement of collagen propeptides may have clinical value in monitoring normal and abnormal growth. The data suggest that the measurement of one propeptide does not offer an advantage over the other.