Nutritional consequences of inflammatory bowel disease on growth

Treating teens: considerations when adolescents want to use complementary and alternative medicine

In this article we examine decision-making about complementary and alternative medicine use when the patient is an adolescent. A case scenario describes patient-parent conflict when a 14-year-old boy who was diagnosed with ulcerative colitis that has continued to progress even with medication refuses recommended surgery despite his physician's and parents' support for that option; he prefers homeopathy instead. We address (1) who has decision-making authority about treatment for young people, (2) how to determine if a young person can consent to or refuse treatment, (3) special considerations when counseling and treating adolescents (whether they can decide about treatment for themselves), and (4) parent-child conflicts about treatment. In addition, we suggest ways that health care providers can foster a trusting relationship with patients and parents.

Altered bone mass in children at diagnosis of Crohn disease: a pilot study

OBJECTIVES

Recent studies have indicated that bone mineral density is reduced in children with inflammatory bowel disease. The exact cause of this reduction is unclear, but it is often attributed to corticosteroid use. This study examined the prevalence of reduced bone mass in otherwise healthy children newly diagnosed with Crohn disease without previous corticosteroid exposure.

METHODS

Eighteen steroid-naive children newly diagnosed with Crohn disease underwent dual energy x-ray absorptiometry. Disease activity, growth and pubertal development, nutritional assessment and bone mass measurements were recorded. z scores were adjusted for bone age.

RESULTS

Five of the 18 patients (28%) had a total bone mineral density z score less than -1 (one had a z score less than -2). Ten (56%) subjects had lumbar spine bone mineral density z scores less than -1 (two had z score less than -2). The subjects had significantly reduced mean lumbar spine bone mineral density z scores (P = 0.002). Delayed pubertal development correlated with whole body bone mineral density z scores (r = 0.64; P = 0.004). Most subjects were not meeting United States recommended dietary allowances for daily intake of calcium, vitamin D and total calories. The majority of subjects were not participating in weight-bearing physical activity.

CONCLUSION

Decreased bone mass is common in steroid naive children newly diagnosed with Crohn disease. Crohn disease appears to contribute to impaired bone mass independent of corticosteroid therapy.

Dietary regulation of intestinal gene expression

We are becoming increasingly aware of inherited genetic abnormalities as causes of disease. However, alterations in gene expression can also contribute to other disease processes. Recently it has been suggested that our environment may alter such genes and thus be a direct influence on disease. Diet is a potent mechanism for altering the environment of cells of most organs, particularly the gastrointestinal tract. This review addresses the influence of nutritional factors on intestinal gene regulation. These influences include insulin, which is not a dietary component but responds to dietary changes, and butyrate, a short chain fatty acid produced by normal intestinal flora. Manipulation of diet may be a means of treating intestinal disorders. Nutritional treatment therefore is also discussed in the light of its effect on gene expression.

Predicting the need for colectomy in pediatric patients with ulcerative colitis

Total colectomy is curative for ulcerative colitis. However, many pediatric patients are medically managed and may not require surgery. There are currently no available criteria to identify children who will benefit from early colectomy. The purpose of this review was to identify criteria associated with the need for colectomy. A 15-year review of patients at a major pediatric center with biopsy-proved ulcerative colitis was conducted. Age at the time of the first symptom, diagnosis, and surgery were recorded as well as steroid dependence, site of disease, extraintestinal manifestations, and family history. Seventy-three patients ranging in age from 1 to 18 years were identified. Thirty-seven patients (50.1%) required total colectomy before the age of 18. The average patient age at the time of the first documented symptom was 11.3 +/- 0.5 years. Among patients who were steroid dependent and had pancolitis, 73% required colectomy. Patients with these factors failed medical management 77% (27 of 35) of the time, and colectomy was performed within 3 years of diagnosis. The combination of steroid dependence and pancolitis was associated with an increased need for colectomy. In pediatric patients with these factors, early colectomy may limit the need to endure prolonged courses of medications and the disability allied with this disease.

The physicochemical environment of the neonatal intestine

Dietary intake, bacterial metabolites, and the secretion of factors (eg, proteins, electrolytes, lipid-soluble molecules, and water) by the body each contribute to the physicochemical environment of the gastrointestinal tract. Peristalsis regulates the changes along the length of the intestine. However, coordinated peristaltic responses develop as premature infants mature. In addition, the physicochemical environment of the center of the intestinal lumen differs from that of the epithelial surface. The area adjacent to the small intestinal epithelium is more acid than the bulk phase. Na+/H+ exchange antiporters in the epithelial cell apical membrane generate this acidity. Mucus maintains the acid microclimate by preventing free diffusion of hydrogen ions into the bulk phase. Development also affects these mechanisms. Changes in the lumenal environment may alter the synthesis of signaling molecules expressed by the intestinal epithelium. Thus, the epithelium, through changes in gene regulation, may act as an active interface that transmits information about the composition of the intestinal lumen to the mucosal immune system. Premature neonates are at risk of necrotizing enterocolitis, a disease almost exclusively associated with oral feeds. The pathogenesis of this condition may, in part, be due to the immaturity of the interactions between the physicochemical environment of the lumen and intestine.

Nutrition in inflammatory bowel disease

Nutrition is clearly disturbed by active intestinal inflammation. Appetite is reduced, yet energy substrates are diverted into the inflammatory process, and thus weight loss is characteristic. The nutritional disturbance represents part of a profound defect of somatic function. Linear growth and pubertal development in children are notably retarded, body composition is altered, and there may be significant psychosocial disturbance. Macrophage products such as tumour necrosis factor-alpha and interleukins-1 and 6 may be the central molecules that link the inflammatory process to this derangement of homeostasis. Intriguingly, there is also increasing evidence that an aggressive nutritional programme may in itself be sufficient to reduce the mucosal inflammatory response. Recent evidence suggests that enteral nutrition alone may reduce many pro-inflammatory cytokines to normal and allow mucosal healing. In addition, specific nutritional components, such as n-3 polyunsaturated fatty acids, may have an anti-inflammatory effect as they may alter the pattern of leukotrienes generated during the immune response. The recent discovery of the specific molecular mediators of appetite and body composition, such as leptin and myostatin, may allow increased therapeutic specificity and further improvement in the nutritional treatment of the inflammatory bowel diseases.

Diet and gene expression in the intestine

Gene expression is central to the pathogenesis of many disorders. An ability to alter the expression of genes would, if their relationship to disease processes were fully understood, constitute a new modality of treatment. This review examines the evidence that nutritional factors can regulate genes in the gastrointestinal epithelium and it discusses the physiological relevance of such alterations in gene expression. Dietary regulation of the genes expressed by the epithelium confers three fundamental advantages for mammals. It enables the epithelium to adapt to the luminal environment to digest and absorb food better; it provides the means whereby mother's milk can influence the development of the gastrointestinal tract; when the proteins expressed by the epithelium act on the immune system, it constitutes a signalling mechanism from the intestinal lumen to the body's defences. Each of these mechanisms is amenable to manipulation for therapeutic purposes.

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.

The nutritional consequences of gastrointestinal disease in adolescence

The growth spurt of adolescence, during which body weight nearly doubles and height increases by 16%, demands an increased delivery of nutrients by the gastrointestinal tract. Chronic disorders of digestion and absorption at this age, therefore have a potentially profound effect upon growth, skeletal maturation and sexual development. Moreover, the emotional climate of adolescence, which requires affiliation with peer groups, and a distancing from authority figures such as doctors and parents, is often associated with a deterioration in drug and dietary compliance and with erratic clinic attendance. Nutritional problems in adolescent patients with Crohn's disease, cystic fibrosis and coeliac disease are the most common. About one third of adolescents with Crohn's disease experience growth failure and delayed sexual development, probably as a consequence of long-term undernutrition. There is a strong argument for the care of these patients being in the hands of paediatric gastroenterologists. Enteral nutrition, often administered overnight, is successful in inducing catch-up growth, and reducing steroid dosage, although resection of diseased gut is often followed by good growth, and surgery should not be overlooked. Cystic fibrosis in adolescence is commonly complicated by protein-energy malnutrition. Pathogenesis includes anorexia, maldigestion and an increase in resting energy expenditure. Malnutrition has been treated by a number of enteral regimens. In general, there is no place for repeated, short-term interventions of less than 6 months. Long-term studies have all shown good nutritional repletion and growth, but results with respect to improved respiratory function are conflicting. More prospective control trials are needed before the precise indications for enteral nutrition in cystic fibrosis can be accurately defined. Once started it is difficult to stop, although preoperative treatment of patients awaiting heart-lung transplantation seems entirely appropriate. The major problem in the management of coeliac disease in adolescence is dietary compliance. Even those patients who claim to have good dietary compliance often have jejunal biopsy evidence of gluten ingestion and tend to be underweight. This is particularly worrying, as after 5 years adherence to a gluten free diet, the increased risk of gastrointestinal malignancy appears to return to normal.