Crohn's disease in adolescents

Positron emission tomography in the investigation of pediatric inflammatory bowel disease

BACKGROUND

Endoscopic and radiologic studies are frequently required in inflammatory bowel disease (IBD) to determine disease activity, extent of disease, and delineating disease type. Positron emission tomography (PET) using fluorine-18-fluoro-deoxyglucose to identify metabolically active tissues may offer a simple noninvasive alternative to conventional studies in identification and localization of active intestinal inflammation in children with IBD. The aim of this study was to assess the value of PET in identifying active intestinal inflammation compared with conventional endoscopic and radiologic studies, including small bowel follow-through and colonoscopy.

METHODS

Sixty-five children were enrolled in the study. This included 55 children (mean age, 13.3 yr; range, 7-18 yr; 20 girls) with newly diagnosed IBD (37) or symptoms suggestive of recurrent disease (18) and 10 children with recurrent abdominal pain (mean age, 12.7 yr; range, 8-15 yr; 7 girls) who were studied with PET, and the results were compared with small bowel follow-through with pneumocolon and/or colonoscopy. Thirty-eight patients had Crohn's disease (17 ileal, 12 ileocolic, 5 pancolonic, 3 left-sided disease, 1 right-sided disease), and 17 had ulcerative colitis (15 pan-colitis, 2 left-sided colitis). Mean time interval between PET and other studies was 30 +/- 17.6 days.

RESULTS

PET correctly identified active inflammatory disease in 80% of children with IBD (81.5% with Crohn's disease; 76.4% with ulcerative colitis) and correctly showed no evidence of inflammation in children with recurrent abdominal pain. Gluorine-18-fluoro-deoxyglucose accumulated at sites that corresponded with active disease at colonoscopy in 83.8% of patients and with small bowel follow-through with pneumocolon 75.0% of the time.

CONCLUSION

This study suggests that PET offers a noninvasive tool for identifying and localizing active intestinal inflammation in children with IBD. PET may not be able to replace conventional studies; however, it may be useful when conventional studies cannot be performed or fail to be completed.

Altered subjective appetite parameters in Crohn's disease patients

BACKGROUND AND AIM

Altered appetite and early satiety may promote anorexia associated with Crohn's disease. The aim of this study was to assess the impact of disease activity on subjective appetite parameters in Crohn's disease patients.

METHODS

Seventeen patients with Crohn's disease and 15 healthy controls (8 M: 7 F, 34 (20-35) years) were studied. Subjects rated their hunger, desire to eat, fullness and level of satiety using visual analogue scales after an overnight fast. Subjects were reassessed after ingestion of 500 and 1000 ml water. Anthropometry was used to determine percentage body fat. Serum leptin & TNF- alpha levels were assessed using immunoassay. Disease activity was determined using the Harvey-Bradshaw index.

RESULTS

Hunger ratings for active Crohn's disease patients were significantly lower than controls at baseline (P<0.05). Desire to eat was lower in patients with active Crohn's disease than controls both at baseline (95% CI, 0.3 mm, 40.7 mm) and after ingestion of 500 ml water (95% CI, 1.25 mm, 51.9 mm) (P<0.05). Serum leptin concentrations were significantly associated with percent body fat (r=0.57;P<0.001) and, after correcting for body fat status, tended to be higher in patients with active Crohn's disease (mean 0.9 ng/ml/% body fat; SD 0.8 ng/ml/% body fat) compared with either patients with inactive disease (mean 0.4 ng/ml/% body fat; SD 0.3 ng/ml/% body fat) or healthy controls (mean 0.3 ng/ml/% body fat; SD 0.2 ng/ml/% body fat) (P=0.15, ns). Appetite parameters and serum leptin concentrations showed no significant correlation.

CONCLUSIONS

Subjective appetite parameters were altered in patients with active Crohn's disease. At baseline, patients with active Crohn's disease were less hungry than healthy controls and had less desire to eat. After ingestion of 500 ml of water, desire to eat was significantly less in patients with active disease as compared with healthy controls. Serum leptin concentration corrected for percent body fat tended to be higher in patients with active Crohn's disease compared with inactive Crohn's disease and healthy controls, but the differences did not reach statistical significance.

Enteral nutrition and corticosteroids in the treatment of acute Crohn's disease in children

BACKGROUND

The optimal treatment of acute Crohn's disease in children remains controversial. In adults, steroid therapy has been shown to be superior to exclusive enteral nutrition. However, enteral nutrition is effective at inducing a remission in many children with acute Crohn's disease. Steroid usage in children has been associated with adverse side effects, particularly with delayed growth and pubertal development.

METHODS

Randomized clinical trials comparing exclusive enteral nutrition with corticosteroids were identified. Two independent reviewers extracted data from selected studies. Studies were assessed for heterogeneity and relative risks for remission induction with enteral nutrition were obtained. Sensitivity analyses were performed in partially randomized studies. Estimates were made of the number of studies needed to overturn the current result. Other outcome measures were qualitatively assessed.

RESULTS

In five randomized clinical trials comprising 147 patients, enteral nutrition was as effective as corticosteroids at inducing a remission (RR = 0.95 [95% confidence interval 0.67, 1.34]). Addition of two further nonrandomized trials did not significantly alter the result. A minimum of 10 further studies, equal in size and outcome to the largest reported pediatric trial to date (n = 68, RR = 0.84), would be required to demonstrate a significant benefit of steroid therapy over enteral nutrition.

CONCLUSIONS

There is no difference in efficacy between enteral nutrition and corticosteroid therapy in the treatment of acute Crohn's disease in children. Improved growth and development, without the side effects of steroid therapy, make enteral nutrition a better choice for first-line therapy in children with active Crohn's disease.

Colonoscopy and technetium-99m white cell scan in children with suspected inflammatory bowel disease

OBJECTIVES

To determine the utility of the technetium-labeled autologous white cell scintigraphy (Tc-WCS) for detecting intestinal inflammation in children with suspected inflammatory bowel disease (IBD). Tc-WCS was compared with colonoscopy and histologic examination.

STUDY DESIGN

Forty-eight children (26 boys; median age, 10 years; range, 2-17 years) with symptoms and signs suggesting IBD had colonoscopy with exploration of terminal ileum and mucosal biopsies. The scans were judged to be abnormal if activity was seen in the gut within the first hour.

RESULTS

Twenty-one patients had a diagnosis of IBD (Crohn's disease, 13; ulcerative colitis, 5; indeterminate colitis, 3); results of scintigraphy were positive in 16 and negative in 5 (sensitivity, 76.2%); the latter had a moderate degree of intestinal inflammation. In 27 patients, IBD was ruled out. Results of scintigraphy were negative in children with non-specific colitis and in those with lymphoid hyperplasia of the terminal ileum, whereas results were positive in 6 of 12 patients with spondyloarthropathy. In children with IBD, there was a significant correlation between results of scintigraphy and endoscopy for the intensity of inflammation (r = 0.70); however, there was a poor correlation regarding the number of involved segments (r = 0.30) because in 16 patients, endoscopy revealed additional diseased segments as compared with scintigraphy.

CONCLUSIONS

A positive Tc-WCS result indicates the presence of an inflammatory process of the gut, whereas a negative test result does not rule out intestinal inflammation, especially when the latter is of moderate degree. Colonoscopy and biopsy are the investigations of choice to establish the diagnosis of IBD and are superior to Tc-WCS in assessing topographic extension of IBD.