Medical therapy to reduce postoperative Crohn's disease recurrence

Natural History and Risk Stratification of Recurrent Crohn's Disease After Ileocolonic Resection: A Multicenter Retrospective Cohort Study

BACKGROUND

Prediction of endoscopic postoperative recurrence (POR) and prophylactic treatment based on clinical risk profile have thus far been inconclusive. This study aimed to examine the association between clinical risk profile and the development of endoscopic POR in a Crohn's disease population without postoperative treatment and to identify individual risk factors of endoscopic POR.

METHODS

Medical records of 142 patients with Crohn's disease during follow-up after ileocecal or ileocolonic resection without prophylactic treatment at 3 referral centers were reviewed. Endoscopic POR was defined as a modified Rutgeerts score ≥i2b. Clinical risk profiles were distilled from current guidelines. Both uni- and multivariate logistic regression analysis were used to assess the relationship between risk profiles and endoscopic POR.

RESULTS

Endoscopic POR was observed in 68 out of 142 (47.9%) patients. Active smoking postsurgery (odds ratio [OR], 3.01; 95% confidence interval [CI], 1.24-7.34; P = 0.02), a Montreal classification of A3 (OR, 3.05; 95% CI, 1.07-8.69; P = 0.04), and previous bowel resections (OR, 2.58; 95% CI, 1.07-6.22; P = 0.03) were significantly associated with endoscopic POR. No significant association was observed between endoscopic POR and any guideline defined as a high-/low-risk profile. However, patients with a combination of any 3 or more European Crohns & Colitis Organisation- (OR, 4.87; 95% CI, 1.30-18.29; P = 0.02) or British Society of Gastroenterology-defined (OR 3.16; 95% CI, 1.05-9.49; P = 0.04) risk factors showed increased odds of developing endoscopic POR.

CONCLUSIONS

Our results suggest that patients with a combination of any 3 or more European Crohns & Colitis Organisation- or British Society of Gastroenterology-defined risk factors would probably benefit from immediate prophylactic treatment.

Tribulus terrestris improves metronidazole-induced impaired fertility in the male mice

INTRODUCTION

Fruit extract of Tribulus terrestris (TT) bears aphrodisiac and antioxidative properties. Antimicrobial drug, metronidazole (MTZ) impairs the spermatogenic activity and fertility in males.

OBJECTIVE

Validation of the use of fruit extract of TT as a supplement against MTZ-induced fertility impairment in males.

METHODS

Adult Swiss strain male mice were administered with 500mg/kgBW/day of MTZ for 28 days. Low (100mg/kgBW/day) and high (200mg/kgBW/day) doses of TT were administered simultaneously with MTZ (500mg/kgBW/day) for same duration. All males were cohabited with virgin proestrus females. Vaginal plug formation was observed to calculate the libido index. Cohabited females were sacrificed on fifteenth day of gestation to dissect out the ovaries and uteri. Fertility index, quantal pregnancy, pre-implantation and post-implantation losses were calculated.

RESULTS

MTZ-treated males showed unaltered mating ability, however, the females impregnated by such males exhibited marked alterations in the fertility index, quantal pregnancy and pre- and post-implantation losses. Supplementation with low dose of TT failed to restore such reproductive toxicities exhibited by administration of MTZ. However, the altered reproductive toxicities were reinstated to control values following supplementation with high dose of TT.

CONCLUSION

The fruit extract of TT may emerge as an effective herbal remedy, correcting the drug-induced fertility impairments in males.

Contribution of intestinal smooth muscle to Crohn's disease fibrogenesis

Mesenchymal cells transdifferentiation and extracellular matrix deposition are involved in the fibrotic process of Crohn's disease (CD). Mesenchymal smooth muscle cells (SMCs) de-differentiation, driven by Platelet-derived growth factor (PDGF) that counteracts Transforming growth factor (TGF-β) has been studied in vascular muscle. The role of SMCs in intestinal fibrogenesis is still not clearly elucidated. Aim of the study was to evaluate the possible myogenic contribution to CD fibrotic process through the comparative analysis of histological, morphometric and molecular alterations occurring in human smooth muscle. Full thickness specimens were obtained from CD (non-involved and stenotic tracts) and healthy (control) ileum. Tissues were processed for histological and immunohistochemical (IHC) analyses and SMCs were isolated from the muscularis propria for morphofunctional and molecular (qPCR) analyses. CD stenotic ileum showed a significant increased thickness of all layers compared to CD non-involved and control ileum. IHC revealed an overexpression of α-smooth muscle actin and collagens I-III throughout all intestinal layers only in stenotic tracts. The two growth factors, PDGF and TGF-β, showed a progressive increase in expression in the muscle layer from CD non-involved to stenotic tracts. Freshly isolated SMCs presented alterations in CD non-involved tracts that progressively increased in the stenotic tracts consisting in a statistical increase in mRNA encoding for PDGF-β and collagen III, paralleled to a decrease in TGF-β and Tribbles-like protein-3 mRNA, and altered morphofunctional parameters consisting in progressive decreases in cell length and contraction to acetylcholine. These findings indicate that intrinsic myogenic alterations occur in CD ileum, that they likely precede stricture formation, and might represent suitable new targets for anti-fibrotic interventions.

Penetrating or stricturing diseases are the major determinants of time to first and repeat resection surgery in Crohn's disease

BACKGROUND

About 80% of patients with Crohn's disease (CD) require bowel resection and up to 65% will undergo a second resection within 10 years. This study reports clinical risk factors for resection surgery (RS) and repeat RS.

METHODS

Retrospective cohort study, using data from patients included in the Swiss Inflammatory Bowel Disease Cohort. Cox regression analyses were performed to estimate rates of initial and repeated RS.

RESULTS

Out of 1,138 CD cohort patients, 417 (36.6%) had already undergone RS at the time of inclusion. Kaplan-Meier curves showed that the probability of being free of RS was 65% after 10 years, 42% after 20 years, and 23% after 40 years. Perianal involvement (PA) did not modify this probability to a significant extent. The main adjusted risk factors for RS were smoking at diagnosis (hazard ratio (HR) = 1.33; p = 0.006), stricturing with vs. without PA (HR = 4.91 vs. 4.11; p < 0.001) or penetrating disease with vs. without PA (HR = 3.53 vs. 4.58; p < 0.001). The risk factor for repeat RS was penetrating disease with vs. without PA (HR = 3.17 vs. 2.24; p < 0.05).

CONCLUSION

The risk of RS was confirmed to be very high for CD in our cohort. Smoking status at diagnosis, but mostly penetrating and stricturing diseases increase the risk of RS.

Role of thiopurine metabolite testing and thiopurine methyltransferase determination in pediatric IBD

Thiopurines have been used in inflammatory bowel disease (IBD) for >30 years, and measurements of both thiopurine methyltransferase (TPMT) and thiopurine (TP) metabolites, 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurine (6-MMP), have been readily available. The North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHAN) Committee on Inflammatory Bowel Disease thought it appropriate to review the present indications for use of TPMT and TP metabolite testing. Substantial evidence demonstrates that TP therapy is useful for both Crohn disease and ulcerative colitis. Review of the existing data yielded the following recommendations. TPMT testing is recommended before initiation of TPs to identify individuals who are homozygote recessive or have extremely low TPMT activity, with the latter having more reliability than the former. Individuals who are homozygous recessive or have extremely low TPMT activity should avoid the use of TPs because of concerns for significant leukopenia. TMPT testing does not predict all cases of leukopenia and has no value to predict hypersensitivity adverse effects such as pancreatitis. Any potential value to reduce the risk of malignancy has not been studied. All individuals taking TPs should have routine monitoring with complete blood cell count and white blood cell count differential to evaluate for leukopenia regardless of TPMT testing results. Metabolite testing can be used to determine adherence with TP therapy. Metabolite testing can be used to guide dose increases or modifications in patients with active disease. Consideration would include either increasing the dose, changing therapy or for those with elevated transaminases or an elevated 6-MMP, using adjunctive allopurinol to help raise 6-thioguanine metabolites and suppress formation of 6-MMP. Routine and repetitive metabolite testing has little or no role in patients who are doing well and taking an acceptable dose of a TP.

Immediate versus tailored prophylaxis to prevent symptomatic recurrences after surgery for ileocecal Crohn's disease?

BACKGROUND

Studies have not established the optimal role for prophylaxis after surgery for Crohn's disease. Some suggest treatment should be initiated within the first month after surgery, whereas others advocate targeted treatment after endoscopic recurrence. In the present study, we compared the efficacy of these competing approaches.

METHODS

One hundred and ninety-nine Crohn's disease patients who underwent ileocecectomy between September 1993 and April 2008 were retrospectively divided into 3 groups based on treatment timing: immediate, tailored, and none. Groups were compared for differences in demographics, pathology, and surgical technique (Chi-square, ANOVA). Rate of symptomatic recurrence (Chi-square), and time to symptomatic recurrence were analyzed (log rank, multivariate Cox proportional hazards).

RESULTS

Sixty-nine (34.7%) received immediate prophylaxis, 32 (16.1%) received tailored prophylaxis, and 98 (49.3%) did not receive any prophylaxis. The groups were similar, though patients receiving immediate prophylaxis were younger and less likely to be lost to follow-up. At 5 years, 62 (31.2%) patients had endoscopic, 46 (23.1%) had symptomatic, and 22 (11%) had surgical recurrences. On simple univariate analysis, patients treated in a tailored fashion at time of endoscopic recurrence appeared more likely than patients treated with immediate prophylaxis to have symptomatic recurrence (43.7% vs 28.9%; P = .02), However, when censored for length of follow-up on multivariate analysis, the only enduring predictor of symptomatic recurrence was Charlson Comorbidity Index (P = .048). Timing of treatment, medicine used for immunoprophylaxis, age, history of prior resection, presence of active disease, and type of anastomosis were not predictive of symptomatic recurrence.

CONCLUSION

Patients offered prophylaxis tailored to endoscopic recurrence have a similar time to symptomatic recurrence as those offered prophylaxis immediately. This suggests that a tailored treatment within a strict protocol of preemptive endoscopic surveillance may be reasonable.

Algorithms outperform metabolite tests in predicting response of patients with inflammatory bowel disease to thiopurines

BACKGROUND & AIMS

Levels of the thiopurine metabolites 6-thioguanine nucleotide (6-TGN) and 6-methylmercaptopurine commonly are monitored during thiopurine therapy for inflammatory bowel disease despite this test's high cost and poor prediction of clinical response (sensitivity, 62%; specificity, 72%). We investigated whether patterns in common laboratory parameters might be used to identify appropriate immunologic responses to thiopurine and whether they are more accurate than measurements of thiopurine metabolites in identifying patients who respond to therapy.

METHODS

We identified 774 patients with inflammatory bowel disease on thiopurine therapy using metabolite and standard laboratory tests over a 24-hour time period. Machine learning algorithms were developed using laboratory values and age in a random training set of 70% of the cases; these algorithms were tested in the remaining 30% of the cases.

RESULTS

A random forest algorithm was developed based on laboratory and age data; it differentiated clinical responders from nonresponders in the test set with an area under the receiver operating characteristic (AUROC) curve of 0.856. In contrast, 6-TGN levels differentiated clinical responders from nonresponders with an AUROC of 0.594 (P < .001). Algorithms developed to identify thiopurine nonadherence (AUROC, 0.813) and thiopurine shunters (AUROC, 0.797) were accurate.

CONCLUSIONS

Algorithms that use age and laboratory values can differentiate clinical response, nonadherence, and shunting of thiopurine metabolism among patients who take thiopurines. This approach was less costly and more accurate than 6-TGN metabolite measurements in predicting clinical response. If validated, this approach would provide a low-cost, rapid alternative to metabolite measurements for monitoring thiopurine use.

Interventions for prevention of post-operative recurrence of Crohn's disease

BACKGROUND

Recurrence of Crohn's disease is common after intestinal resection. A number of agents have been studied in controlled trials with the goal of reducing the risk of endoscopic or clinical recurrence of Crohn's disease following surgery.

OBJECTIVES

To undertake a systematic review of the use of medical therapies for the prevention of post-operative recurrence of Crohn's disease

SEARCH STRATEGY

MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched to identify relevant studies. References from selected papers and abstracts from Digestive Disease Week were also searched.

SELECTION CRITERIA

Randomised controlled trials that compared medical therapy to placebo or other medical agents for the prevention of recurrence of intestinal Crohn's disease were selected for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors reviewed all abstracts containing search terms, and those meeting inclusion criteria were selected for full data abstraction. Dichotomous data were summarised using relative risk and 95% confidence intervals. A fixed-effects model was used, and sensitivity analysis performed.

MAIN RESULTS

Twenty-three studies were identified for inclusion. Probiotics were not superior to placebo for any outcome measured. The use of nitroimidazole antibiotics appeared to reduce the risk of clinical (RR 0.23; 95%CI 0.09 to 0.57, NNT=4) and endoscopic (RR 0.44; 95%CI 0.26 to 0.74, NNT = 4) recurrence relative to placebo. However, these agents were associated with higher risk of serious adverse events (RR 2.39, 95% CI 1.5 to 3.7). Mesalamine therapy was associated with a significantly reduced risk of clinical recurrence (RR 0.76; 95% CI 0.62 to 0.94, NNT = 12), and severe endoscopic recurrence (RR 0.50; 95% CI 0.29 to 0.84, NNT = 8) when compared to placebo. Azathioprine/6MP was also associated with a significantly reduced risk of clinical recurrence (RR 0.59; 95% CI 0.38 to 0.92, NNT = 7), and severe endoscopic recurrence (RR 0.64; 95% CI 0.44 to 0.92, NNT = 4), when compared to placebo. Neither agent had a higher risk than placebo of serious adverse events. When compared to azathioprine/6MP, mesalamine was associated with a higher risk of any endoscopic recurrence (RR 1.45, 95% CI 1.03 to 2.06), but a lower risk of serious adverse events (RR 0.51; 95% CI 0.30 to 0.89). There was no significant difference between mesalamine and azathioprine/6MP for any other outcome.

AUTHORS' CONCLUSIONS

There are insufficient randomised controlled trials of infliximab, budesonide, tenovil and interleukin-10 to draw conclusions. Nitro-imidazole antibiotics, mesalamine and immunosuppressive therapy with azathioprine/6-MP or infliximab all appear to be superior to placebo for the prevention of post-operative recurrence of Crohn's disease. The cost, toxicity and tolerability of these approaches require careful consideration to determine the optimal approach for post-operative prophylaxis.

Meta-analysis of medical treatment and placebo treatment for preventing postoperative recurrence in Crohn's disease (CD)

INTRODUCTION

We performed a meta-analysis to compare the clinical and endoscopic recurrence of medical treatment and placebo treatment for preventing postoperative recurrence in Crohn's disease.

MATERIALS AND METHODS

Trials were located through Medline, Embase, the Cochrane Central Register of Controlled Trials, Ovid, Sciencedirect, and Ingenta electronic databases. From 124 articles screened, 14 were identified as randomized placebo-controlled trials and were included for data extraction. Main outcome measures were clinical recurrence, endoscopic recurrence, and severe endoscopic recurrence. The meta-analysis was performed with the fixed-effects model.

RESULT

Fourteen studies with 1,497 participants were analyzed. In the intention-to-treat analysis, medical treatment was associated with a significantly lower incidence of clinical recurrence (relative risk of 0.74, 95% confidence interval 0.64-0.87, P = 0.000], but there were no significant differences in endoscopic recurrence (0.94, 0.83-1.07, P = 0.353) and severe endoscopic recurrence (0.83, 0.60-1.16, P = 0.281) between the two groups. When using per-protocol analysis, the results is similar, medical treatment was associated with a significantly lower incidence of clinical recurrence (0.84, 0.72-0.97, P = 0.020), but there were no significant differences in endoscopic recurrence (0.94, 0.85-1.05, P = 0.268) or severe endoscopic recurrence (0.76, 0.55-1.04, P = 0.084) between the two groups of patients.

CONCLUSIONS

Medical treatment has a sufficiently beneficial effect on decreasing the risk of clinical postoperative recurrence in patients with CD.

Managing medical complications and recurrence after surgery for Crohn's disease

Each of the medical and surgical therapies for Crohn's disease has inherent advantages and disadvantages that must be balanced for patients with moderate to severe disease. Most patients with Crohn's disease require surgery at some point during the lifelong illness, but surgical therapy is not curative for most patients, as postoperative recurrence of Crohn's disease is common and can pose diagnostic and therapeutic challenges. Disease monitoring and appropriate prophylaxis are necessary in patients at high risk.

Meta-analysis of the placebo rates of clinical relapse and severe endoscopic recurrence in postoperative Crohn's disease

BACKGROUNDS & AIMS

The benefit of therapy for prevention of postoperative recurrence of Crohn's disease (CD) is limited. Clinical relapse and severe endoscopic recurrence are the main outcomes in the evaluation of trials on prevention of recurrence. The aim of this meta-analysis was to focus on knowledge of the placebo rates of relapse and recurrence in postoperative CD and to identify factors influencing these rates.

METHODS

We performed a meta-analysis of placebo-controlled, randomized clinical trials, evaluating therapies for postoperative maintenance of CD identified on MEDLINE from 1990 to 2006. Primary outcomes were clinical relapse and severe endoscopic recurrence.

RESULTS

The pooled estimate of the placebo relapse rate was 23.7% (95% confidence interval [CI], 13-35; range 0-78). There was a statistically significant heterogeneity among studies (P < .0001). Heterogeneity in clinical relapse was present even if the trials were stratified according to the time of outcome. The pooled estimate of the severe endoscopic recurrence rate was 50.2% (95% CI, 28-73; range, 30-79). There was significant heterogeneity among the studies (P = .00038). This heterogeneity was less apparent in studies carried out within 12 months. The logistic analysis identified only duration of follow-up as a variable associated with different placebo relapse rates. No variable was identified as a predictor of a placebo endoscopic recurrence rate.

CONCLUSIONS

There is significant heterogeneity among placebo rates in postoperative CD. No single design variable was identified that explained the heterogeneity in placebo outcomes for clinical or endoscopic recurrence.

Treatment of inflammatory bowel disease: a review of medical therapy

Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the gastrointestinal tract. While a cure remains elusive, both can be treated with medications that induce and maintain remission. With the recent advent of therapies that inhibit tumor necrosis factor (TNF) alpha the overlap in medical therapies for UC and CD has become greater. Although 5-ASA agents have been a mainstay in the treatment of both CD and UC, the data for their efficacy in patients with CD, particularly as maintenance therapy, are equivocal. Antibiotics may have a limited role in the treatment of colonic CD. Steroids continue to be the first choice to treat active disease not responsive to other more conservative therapy; non-systemic steroids such as oral and rectal budesonide for ileal and right-sided CD and distal UC respectively are also effective in mild-moderate disease. 6-mercaptopurine (6-MP) and its prodrug azathioprine are steroid-sparing immunomodulators effective in the maintenance of remission of both CD and UC, while methotrexate may be used in both induction and maintenance of CD. Infliximab and adalimumab are anti-TNF agents approved in the US and Europe for the treatment of Crohn's disease, and infliximab is also approved for the treatment of UC.

Current therapy of inflammatory bowel disease in children

Ulcerative colitis (UC) and Crohn disease (CD) are chronic intestinal inflammatory diseases that can present as bloody diarrhea, abdominal pain, and malnutrition. Collectively, these disorders are referred to as inflammatory bowel disease (IBD). All patients with IBD share a common pathophysiology. However, there are a number of developmental, psychosocial, and physiologic issues that are unique to the approximate, equals 20% of patients that present during childhood or adolescence. These include the possibility of disease-induced delays in linear growth or physical development, differences in drug dosing, and the changes in social and cognitive development that occur as children move from school-age years into adolescence and early adulthood. Gastroenterologists caring for these children must therefore develop an optimal regimen of pharmacologic therapies, nutritional management, psychologic support, and properly timed surgery (when necessary) that will maintain disease remission, minimize disease and drug-induced adverse effects, and optimize growth and development. This article reviews current approaches to the management of patients with UC and CD and highlights issues specific to the treatment of children with IBD. The principal medical therapies used to induce disease remission in patients with UC are aminosalicylates (for mild disease), corticosteroids (for moderate disease), and cyclosporine (ciclosporin) (for severe disease). If a patient responds to the induction regimen, maintenance therapies that are used to prevent disease relapse include aminosalicylates, mercaptopurine, and azathioprine. Colectomy with creation of an ileal pouch anal anastomosis (J pouch) has become the standard of care for patients with severe or refractory colitis and results in an improved quality of life in most patients. Therefore, the risks associated with using increasingly potent immunosuppressant agents must be balanced in each case against a patient's desire to retain their colon and avoid a temporary or potentially permanent ileostomy. Decisions about drug therapy in the management of patients with CD are more complex and depend on both the location (e.g. gastroduodenal vs small intestinal vs colonic), as well as the behavior of the disease (inflammatory/mucosal vs stricturing vs perforating) in a given patient. Induction therapies for CD typically include aminosalicylates and antibiotics (for mild mucosal disease), nutritional therapy (including elemental or polymeric formulas), corticosteroids (for moderate disease), and infliximab (for corticosteroid-resistant or fistulizing disease). Aminosalicylates, mercaptopurine, azathioprine, methotrexate, and infliximab can be used as maintenance therapies. Because surgical treatment of CD is not curative, it is typically reserved for those patients either with persistent symptoms and disease limited to a small section of the intestine (e.g. the terminal ileum and cecum) or for the management of complications of the disease including stricture or abdominal abscess. When surgery is necessary, maintenance medications administered postoperatively will postpone recurrence. Patients with UC and CD are at risk for the development of micronutrient deficiencies (including folate, iron, and vitamin D deficiencies) and require close nutritional monitoring. In addition, patients with UC and CD involving the colon are at increased risk of developing colon cancer, and should be enrolled into a colonoscopy surveillance program after 8-10 years of disease duration.

Postoperative Crohn's disease

More than three quarters of patients with Crohn's disease (CD) will require surgery. After resection, disease recurs postoperatively with a median time to second resection of about 10 years. Despite its importance, the postoperative period remains one of the most poorly understood clinical settings in the field. Postoperatively, CD may exhibit unique pathophysiologic features, but the current state of knowledge does not allow for identification of patients at risk for relapse, and leaves clinicians without guidance on optimal maintenance treatment. Therapies used as maintenance for CD in other settings may have different efficacies when used after surgery, and clinical research in patients requiring surgery is limited by the subset of patients available for study. Despite the many limitations in current knowledge of postoperative CD, it is an exciting field because new developments have improved patient care, and ongoing research has the potential for further gains.

Mesalamine derivatives in the treatment of Crohn's disease

The role of the aminosalicylates for induction therapy of mild moderate ulcerative colitis and as maintenance treatment has been substantiated by a large series of controlled clinical trials and confirmatory meta-analyses. Both sulfasalazine and newer derivatives are effective in preventing relapses. It remains to be determined whether certain high-risk groups of patients may benefit from higher doses of mesalamine induction or maintenance therapy. Mesalamine derivatives are also of benefit in the treatment of Crohn's disease. Sulfasalazine is likely not effective in the maintenance of Crohn's disease, although other mesalamine formulations continue to show some prophylactic activity after mesalamine induced remissions and for patients with disease of the ileum who have undergone surgical resection.

Inflammatory bowel disease: dysfunction of GALT and gut bacterial flora (II)

The precise cause(s) of Crohn's disease and ulcerative colitis are unknown. From animal models and human studies it is well established that gut bacterial flora are essential for inducing the bowel inflammation. Animal models, when kept in a germ-free environment, do not develop colitis until the gut flora is reconstituted. It is not clear whether the bacterial antigens (Ags) from the normal flora or some other pathogenic bacterial Ags induce/propagate the inflammatory process in inflammatory bowel disease (IBD). Despite extensive research it has not been possible to identify any specific bacteria or virus as a credible cause of IBD. Recent understanding of quorum sensing molecules (QSMs) secreted by bacteria helps to explain the community behaviour in bacterial species. When QSMs reach a defined concentration, they activate bacterial proliferation and a number of virulence genes. Also, these molecules have been found to modulate the immune system to the advantage of the gut bacteria. They have not been well studied, however, in the gut. Inappropriate secretion of QSMs may alter the gut-associated lymphoid tissue (GALT) and, thereby, deregulate the immune tolerance normally present. Usefulness of probiotics and their immune modulating effects are being increasingly reported. Probiotics are also being used in the treatment of IBD. The interaction between the epithelial cells and the gut flora is very important as this is the first line of contact; this interaction may determine the induction of tolerance and mucosal integrity or immune activity, tissue inflammation and abnormal permeability. The latter is documented in patients with IBD and their healthy relatives. This may be an important factor in disruption of mucosal integrity and GALT dysfunction.

Crohn's disease: step up or top down therapy

The concept of a 'step-up' or 'top-down' approach to the treatment of Crohn's disease has evolved from the impact of novel anti-TNF (anti-tumour necrosis factor) therapies that have been effective for patients who are refractory to other medical treatments. In addition, the potential to produce mucosal healing with anti-TNF treatments without the well-recognized systemic complications of glucocorticoid therapy has created debate as to whether earlier, more aggressive, therapies should be advocated. This controversy arises at a time when the concept of sequential therapy to induce and maintain remissions for Crohn's disease has begun to be accepted and precedes our ability to define the concept of disease modification or predict the natural history of Crohn's disease based upon clinical, pathological, molecular orgenetic criteria. Evidence for therapeutic efficacy in Crohn's disease is presented as a prologue to considerations necessary to determine the benefits and risks of early aggressive treatment versus sequential approaches based upon disease severity.

Effects of natural polysaccharide addition on drug release from calcium-induced alginate gel beads

Calcium-induced alginate gel beads (Alg-Ca) containing various polysaccharides, including an alginate hydrolysate, were prepared and the drug release profiles were investigated. Hydrocortisone (HC) was gradually released from Alg-Ca into the mimic gastric fluid, while in intestinal fluid, it was quickly released with the dissolution of Alg-Ca. However, with Alg-Ca containing 5% chitin (CT), dissolution of Alg-Ca was not observed, and release of HC showed apparent zero-order kinetics. Furthermore, addition of the alginate hydrolysate altered the HC-release profile for Alg-Ca.

Corticosteroids in Crohn's disease

Crohn's disease is a lifelong illness characterized by chronic recurrent flares. The precise etiology of Crohn's disease is unknown. However, it appears to involve an enhanced systemic immune response and intensified local intestinal mucosal inflammatory activity, mediated through various inflammatory cells and an array of proinflammatory cytokines. Corticosteroids have been the mainstay of treatment of Crohn's disease. The controlled trials of the National Cooperative Crohn's Disease Study and the European Cooperative Crohn's Disease Study established that corticosteroids were effective for the induction of remission in Crohn's disease for the duration of the studies (6-17 wk). However, corticosteroids have not been shown to have an impact on the maintenance of long term remission in patients with Crohn's disease. In addition, they are associated with a high potential for dependence and serious toxic side effects. Alternative classes of medical therapy for Crohn's disease, including modified corticosteroids and a group of new biological therapies, have proven to be efficacious in the management of active and/or quiescent Crohn's disease.

Medical treatment of Crohn's disease

Crohn's disease is not medically (and is rarely surgically) curable. Patients do, however, live a normal life span. The goal of therapy is to optimize the quality of life, minimize disease activity and disease-related complications, and avoid therapeutic toxicity.

Medical management of postoperative complications of inflammatory bowel disease: pouchitis and Crohn's disease recurrence

Surgical intervention is often required for patients with inflammatory bowel disease. Total proctocolectomy with ileal pouch-anal anastomosis is the surgical treatment of choice for patients with ulcerative colitis. The main long-term complication of this surgery is pouchitis, with 10-year cumulative incidence rates between 24% and 46%. For patients with Crohn's disease, postoperative recurrence is a significant problem, with clinical recurrence rates as high as 55% at 5 years and 76% at 15 years. Increasing evidence suggests that postoperative medical therapy has the potential to decrease the risk of postoperative Crohn's disease recurrence.

[Acute peritonitis due to perforating crohn's disease]

Peritonitis is an infrequent complication of perforating Crohn's disease. Three patients, aged between 25 and 41 years, underwent surgery for peritonitis due to perforating Crohn's disease in the terminal ileum. The underlying disease differed in each patient (one patient was asymptomatic and two presented acute episodes of the disease; of these two patients, corticoids were required in one to control symptomatology). Treatment consisted of intestinal resection with primary anastomosis. In all three patients evolution was satisfactory. Taking only patients treated in our hospital into account, the frequency of peritonitis due to perforating Crohn's disease in our area is high (more than 11%). Intestinal resection with primary anastomosis should be performed whenever possible.