Addition of metronidazole to azathioprine for the prevention of postoperative recurrence of Crohn's disease: a randomized, double-blind, placebo-controlled trial.

BACKGROUND: Endoscopic recurrence occurs in up to 80% of patients with Crohn's disease 1 year after intestinal resection. Imidazole antibiotics, thiopurines, and particularly their combination have proven efficacy in preventing endoscopic recurrence. The aim of the study was to compare the efficacy of the addition of metronidazole (for 3 months after the surgical treatment) to azathioprine for the prevention of postsurgical endoscopic recurrence. METHODS: A pilot study was made of 50 patients with Crohn's disease undergoing intestinal resection with ileocolic anastomosis and treated with 2 to 2.5 mg/kg of azathioprine per day for 1 year. The patients were randomized to receive additional 15 to 20 mg/kg of metronidazole per day or placebo for the first 3 months (n = 25 per arm). Endoscopic assessment was performed 6 and 12 months after the surgical resection. The primary end point was the prevention of endoscopic recurrence as defined by a Rutgeerts score of <2 at 6 months. The initial sample size had an 80% statistical power in detecting an absolute risk reduction of ≥30%. RESULTS: Endoscopic recurrence occurred in 28% and 44% of the patients at 6 months (P = 0.19) and in 36% and 56% (P = 0.15) at 12 months in the metronidazole and placebo groups, respectively. No statistically significant differences were found between the treatment groups regarding severe endoscopic recurrence (Rutgeerts score ≥ 3) at 6 and 12 months. Likewise, there were no differences in the rate of adverse events between the treatment groups. CONCLUSIONS: The addition of metronidazole to azathioprine did not significantly reduce the risk of endoscopic recurrence beyond azathioprine alone in this study but does not worsen its safety profile.

Omega-3 fatty acids and inflammatory bowel diseases - a systematic review.

BACKGROUND & AIM: Despite their well known anti-inflammatory actions, the clinical usefulness of omega-3 PUFA in inflammatory bowel disease is controversial. We aimed to systematically review the available data on the performance of omega-3 PUFA as therapeutic agents in these patients. METHODS: Electronic databases were systematically searched for RCT of fish oil or omega-3 PUFA therapy in both active and inactive ulcerative colitis or Crohn's disease, without limitation on either the length of therapy or the form it was given, including nutritional supplements and enteral formula diets. Eligible articles were assessed for methodological quality on the basis of the adequacy of the randomisation process, concealment of allocation, blinding of intervention and outcome, possible biases, and completeness of follow-up. The five-point Oxford quality score was calculated. RESULTS: A total of 19 RCT were finally selected for this review. Overall, available data do not allow to support the use of omega-3 PUFA supplementation for the treatment of both active and inactive inflammatory bowel disease. Negative results are quite consistent in trials assessing the use of omega-3 PUFA to maintain disease remission, particularly ulcerative colitis, and to a lesser extent Crohn's disease. Trials on their use in active disease do not allow to draw firm conclusions mainly because the heterogeneity of design (ulcerative colitis) or their short number (Crohn's disease). In most trials, the appropriateness of the selected placebo is questionable. CONCLUSION: The present systematic review does not allow to make firm recommendations about the usefulness of omega-3 PUFA in inflammatory bowel disease.

Apoptosis resistance of mucosal lymphocytes and IL-10 deficiency in patients with steroid-refractory Crohn's disease.

BACKGROUND: Apoptosis resistance of T-cells is considered an abnormality of immune pathways in Crohn's disease (CD). It has been previously shown that corticosteroids induce apoptosis of cells involved in inflammation. Thus, our aim was to assess the apoptosis of mononuclear cells and pro/antiinflammatory cytokines in the intestinal mucosa of patients with active CD, related to steroid response, and identify cellular and molecular factors that may predict this response to therapy. METHODS: Patients with CD (n = 26), ulcerative colitis (UC) (n = 32), and controls (n = 10) were prospectively studied with mucosal biopsies before and 7-10 days after corticosteroid treatment. Immunophenotype and apoptosis of T and B lymphocytes, plasma cells, and macrophages were assessed by flow cytometry, immunohistochemistry, and immunofluorescence. The cytokine expression pattern was evaluated by quantitative polymerase chain reaction (PCR). RESULTS: Apoptosis resistance of T and B lymphocytes was observed only in steroid-refractory and -dependent CD patients as compared to responsive patients (P = 0.032; P = 0.004, respectively), being evident after steroid treatment. Interleukin (IL)-10 was markedly increased at baseline in steroid-responsive patients compared to the nonresponders (P = 0.006; sensitivity: 88.8%; specificity: 66.6% to predict steroid response). CONCLUSIONS: Apoptosis resistance of mucosal T and B cells in steroid-refractory and -dependent CD patients appears during the evolution of the acute phase, limiting its clinical application as a predictor marker. In contrast, increased expression of IL-10 at an early stage of active steroid-sensitive CD patients supports its usefulness at predicting a good steroid response. Steroid-dependent and -refractory CD patients share similar molecular and cellular pathophysiological mechanisms.

Resequencing of positional candidates identifies low frequency IL23R coding variants protecting against inflammatory bowel disease.

Genome-wide association studies (GWAS) have identified dozens of risk loci for many complex disorders, including Crohn's disease. However, common disease-associated SNPs explain at most ∼20% of the genetic variance for Crohn's disease. Several factors may account for this unexplained heritability, including rare risk variants not adequately tagged thus far in GWAS. That rare susceptibility variants indeed contribute to variation in multifactorial phenotypes has been demonstrated for colorectal cancer, plasma high-density lipoprotein cholesterol levels, blood pressure, type 1 diabetes, hypertriglyceridemia and, in the case of Crohn's disease, for NOD2 (refs. 14,15). Here we describe the use of high-throughput resequencing of DNA pools to search for rare coding variants influencing susceptibility to Crohn's disease in 63 GWAS-identified positional candidate genes. We identify low frequency coding variants conferring protection against inflammatory bowel disease in IL23R, but we conclude that rare coding variants in positional candidates do not make a large contribution to inherited predisposition to Crohn's disease.

Regulation of colorectal cancer cell apoptosis by the n-3 polyunsaturated fatty acids Docosahexaenoic and Eicosapentaenoic.

Several studies have suggested that the n-3 fatty acids Docosahexaenoic (DHA) and Eicosapentaenoic (EPA) have an important protective effect on colorectal cancer, and this could be at least partly due to their proapoptotic activity. It is unclear, however, how this phenomenon is triggered and what mechanisms are implicated. Here, we show that both DHA and EPA have an important proapoptotic effect on colorectal cancer cells with different molecular phenotypes but not in noncancerous cells. Apoptosis is caspase dependent, and both intrinsic and extrinsic pathways are implicated. The dimerization of Bax and Bak, the depolarization of the mitochondrial membrane, and the subsequent release of cytochrome c and Smac/Diablo to the cytosol evidence the activation of the intrinsic pathway. The implication of the extrinsic pathway is shown by the activation of caspase-8, along with the down-regulation of FLIP. The timing of caspase-8 activation, and the oligomerization of Bid with Bax, suggest a cross-talk with the intrinsic pathway. None of the death receptors that commonly initiate the extrinsic pathway: FAS, TNF-R1, and TRAIL-R2 are found to be responsible for triggering the apoptosis cascade induced by DHA and EPA. Neither PPARgamma nor cyclooxygenase-2, two likely candidates to regulate this process, play a significant role. Our findings suggest that the down-regulation of two key regulatory elements of the extrinsic and intrinsic pathways, FLIP and XIAP, respectively, is determinant in the induction of apoptosis by DHA and EPA. These fatty acids could potentially be useful adjuvant anticancer agents in combination with other chemotherapeutic elements.

Prospective, observational, cross-sectional study of intestinal infections among acutely active inflammatory bowel disease patients.

BACKGROUND: Intestinal infections have been claimed to precipitate or aggravate flares of inflammatory bowel disease (IBD). The reported incidence of such infections among IBD patients varies between 9 and 13%, but only a few prospective studies have been conducted. AIMS: To evaluate the incidence of intestinal infections by enteropathogens in patients with active IBD, their impact on clinical outcome, and to identify associated risk factors. PATIENTS AND METHODS: Consecutive patients admitted because of a relapse or suspected onset of IBD were prospectively included. At admittance, stool samples for culture, examination for intestinal parasites, and cytotoxin assay for Clostridium difficile were collected. Baseline clinical characteristics, potential risk factors for gastrointestinal infections, and clinical outcome were recorded. RESULTS: Ninety-nine episodes were included. Six intestinal infections were diagnosed in 6 patients (5 ulcerative colitis, 1 ileocolonic Crohn's disease), Campylobacter jejuni being the most frequent isolated microbe (n = 5). None of the patients with intestinal infection needed surgery, but two of them required second-line therapies. CONCLUSIONS: Gastrointestinal infections among IBD patients do not exceed 10% and occur mostly in patients with extensive involvement of the colon. Infection by enteropathogenic bacteria does not appear to be associated with a poorer clinical outcome of the IBD flare.

Tuberculous chemoprophylaxis requirements and safety in inflammatory bowel disease patients prior to anti-TNF therapy.

BACKGROUND: Preventive actions are advised since the use of anti-tumor necrosis factor (TNF) agents is known to increase the risk of tuberculosis (TB). No data related to the effectiveness and safety of the preventive chemoprophylaxis (ChP) for TB in inflammatory bowel disease (IBD) patients are available. The goal was to evaluate the requirements, effectiveness, and safety profile of ChP in IBD patient candidates for anti-TNF therapy. METHODS: All IBD patients diagnosed with latent TB while evaluated for anti-TNF therapy from the IBD database of 9 Spanish centers were included. Epidemiological and clinical data, risk factors for hepatotoxicity, ChP regimens, and side effects were registered. RESULTS: Sixty-three out of 497 IBD evaluated patients (12.5%) had latent TB. Sixty-eight percent were on immunomodulators and 42% on systemic corticosteroids when a TB skin test (TST) was performed. The detection of a positive TST was done in 86% after a single exposure, but 14% needed a booster. All but 1 were treated with isoniazid alone for 6 or 9 months, and only 1 case required ChP discontinuation because of hepatotoxicity. No risk factors for hepatotoxicity were found. No cases of active TB were noticed in the 67 patients further treated with anti-TNF therapy. CONCLUSIONS: More than 10% of Spanish IBD patients who are candidates for anti-TNF therapy have latent TB. TST retest is required to identify at least 14% of such patients; therefore, it should be considered if the initial TST is negative. ChP is safe in IBD patients even in those taking concomitant, potentially hepatotoxic drugs.

Long-term methotrexate for Crohn's disease: safety and efficacy in clinical practice.

GOALS: To assess the efficacy and safety profile of methotrexate (MTX) for the treatment of Crohn's disease (CD) in clinical practice. BACKGROUND: MTX is widely used for some chronic immunologic diseases. Although some randomized controlled trials suggest its efficacy in CD, this drug remains a second-line, underused, immunomodulator. STUDY: Medical records of all patients treated with MTX for CD in our center (n=44) were reviewed. Clinical and epidemiologic parameters, including risk factors for hepatotoxicity, were registered. RESULTS: MTX was prescribed mainly for steroid-dependency (n=22) and as concomitant treatment to infliximab (n=18). Mean duration of treatment was 22.9+/-19 months, with a mean cumulative dose of MTX of 1169+/-784 mg. Thirty-nine percent of patients developed drug-related side effects, hepatotoxicity being the most frequent [13 patients (30%)]. However, only 5 patients (11%) had to discontinue MTX. In steroid-dependent CD patients, disease remission and complete steroid withdrawal was achieved in 77% of cases. Seven patients lost their initial response to MTX during follow-up, leading to a cumulative probability of remission of 39% after 3 years of treatment. CONCLUSIONS: MTX is well tolerated in most CD patients. Although a great proportion of steroid-dependent CD patients achieve disease remission and steroid withdrawal, there is a trend to a loss of efficacy with time. Larger, long-term studies are necessary to establish the role of MTX in the management of CD.

Impact of azathioprine on the prevention of postoperative Crohn's disease recurrence: results of a prospective, observational, long-term follow-up study.

BACKGROUND: Postoperative recurrence (PR) occurs early after intestinal resection in >75% of Crohn's disease (CD) patients. No well-established strategy for long-term PR prevention is available. The aim was to prospectively evaluate the long-term endoscopic and clinical outcomes of postoperative CD on maintenance treatment with azathioprine (AZA), especially in patients who developed endoscopic lesions confined to the ileocolic anastomosis. METHODS: Long-term AZA therapy (2-2.5 mg/kg/day) was initiated immediately after surgery in 56 consecutive patients who underwent a curative intestinal resection. Clinical and biological assessments every 3 months, as well as yearly endoscopic evaluation, were performed until the end of the study or clinical PR (CPR). RESULTS: Thirty-seven patients (70%) showed mucosal lesions at endoscopy after a median of 12 months (range 12-60); however, in 15 of these patients lesions were confined to the anastomosis and only 6 showed endoscopic progression, but none of them developed CPR. Among the remaining 22 patients with endoscopic PR (EPR), 23% suffered a CPR during follow-up. Thirty percent of patients remained free of EPR after a median follow-up of 33 months (range 12-84). The cumulative probability of EPR was 44%, 53%, 69%, and 82%, at 1, 2, 3, and 5 years, respectively. No predictive factors of EPR were found. CONCLUSIONS: Early postoperative use of AZA seems to delay EPR development in comparison to historical series or placebo groups in randomized controlled trials. Although usually considered as endoscopic recurrence, those lesions confined to the ileocolonic anastomosis are not likely to progress or to become symptomatic in the short term.

Performance of different microsatellite marker panels for detection of mismatch repair-deficient colorectal tumors.

BACKGROUND: Colorectal tumors caused by failure of the DNA mismatch repair system commonly show microsatellite instability. Our goals were to compare the performance of two panels of markers (a panel previously recommended by the National Cancer Institute [NCI] and a pentaplex of mononucleotide repeats) and to devise the simplest diagnostic strategy for identification of patients with colorectal cancer characterized by defects in mismatch repair. METHODS: We recruited 1058 patients who were newly diagnosed with colorectal cancer. DNA from fresh-frozen and paraffin-embedded tumors was tested for microsatellite instability, using the NCI-recommended panel of microsatellite markers and the pentaplex panel of mononucleotide repeats, respectively, as templates for polymerase chain reactions (PCRs). Microsatellite instability in fresh-frozen tumors was also assessed using the pentaplex panel of mononucleotides in a crossover analysis. The expression of mismatch repair proteins (MLH1, MSH2, MSH6, and PMS2) in the tumors was determined immunohistochemically. The sensitivity and specificity with which the marker panels identified tumors with deficiencies in the expression of mismatch repair proteins were calculated. All statistical tests were two-sided. RESULTS: The sensitivity and positive predictive value of the NCI panel were 76.5% (95% confidence interval [CI] = 61% to 92%) and 65.0% (95% CI = 49% to 81%), respectively; corresponding values for the mononucleotide pentaplex panel were 95.8% (95% CI = 89% to 103%) and 88.5% (95% CI = 79% to 98%), respectively. A panel consisting of the mononucleotide repeat markers BAT26 and NR24 alone had the same predictive value as the pentaplex panel of mononucleotide repeats. CONCLUSIONS: The pentaplex panel of mononucleotide repeats performs better than the NCI panel for the detection of mismatch repair-deficient tumors. Simultaneous assessment of the instability of BAT26 and NR24 is as effective as use of the pentaplex panel for diagnosing mismatch repair deficiency.

[Use of complementary and alternative medicine and drug abuse in patients with inflammatory bowel disease]. / Utilización de medicinas alternativas y consumo de drogas por pacientes con enfermedad inflamatoria intestinal.

BACKGROUND AND OBJECTIVE: The use of complementary and alternative medicine (CAM) is increasing in last years. Studies performed out of Spain have reported rates of CAM use of 40-50% among IBD patients. There are no available data on drug abuse among IBD patients. The aims of our study were to evaluate the rate and associate factors of CAM use and drug abuse among Spanish IBD patients. PATIENTS AND METHOD: Anonymous, structured questionnaire, administered to consecutive patients with IBD of at least 2 years of duration, seen in a IBD outpatient clinic. RESULTS: Twenty-six per cent of the 214 included patients reported having used CAM. No associated factors were found, although patients with ulcerative colitis tended to a higher rate of CAM use. Ten per cent of patients admitted to consume drugs, mainly cannabis derivatives. Younger age and college and universitary degree were the only factors associated to cannabis consumption. CONCLUSIONS: The rate of CAM use in IBD patients from a Spanish referral centre is lower than those described in other countries. About 10% of IBD patients consume cannabis, but only one third of them inform their physician about it.

Endoscopic removal of large sessile colorectal adenomas: is it safe and effective?

Large sessile colorectal polyps represent a treatment challenge. Nowadays there are discrepancies regarding how to proceed with them because of morbidity, the possibility of incomplete endoscopic resection, and the high possibility of a coexisting malignancy. This study was performed to determine the safety and effectiveness of endoscopic removal of sessile colorectal adenomas larger than 4 cm. Seventy-four patients with a total of 74 sessile polyps larger than 4 cm in diameter were treated endoscopically. Polyps were removed using argon plasma coagulation (APC) as an adjunct to piecemeal technique. Surgery was recommended in patients with invasive neoplasia. Patients with favorable histology (low-grade dysplasia [LDG] or high-grade dysplasia [HGD]) were followed up with monthly endoscopies untill total ablation of the lesion, and then at 3- to 6-month intervals. LGD was found in 38 patients, HGD in 24, and invasive neoplasia in the remaining 12 patients. A total of 54 patients were followed up for at least 6 months. Recurrence rate of polyps with favorable histology was 9.2% (5/54). Postpolypectomy bleeding was the only complication, observed in 10 patients (13.5%). We conclude that piecemeal polypectomy plus APC without saline injection, performed by an expert endoscopist, is a safe and effective treatment for all LGD or HGD large sessile colorectal polyps.

Medication-taking behavior in a cohort of patients with inflammatory bowel disease.

Recent studies have shown a low adherence rate to maintenance treatment in patients with inflammatory bowel disease (IBD). We sought to assess the medication-taking behavior in a cohort of patients with IBD. We prospectively included IBD patients from the outpatient clinic who agreed to answer a questionnaire about prescribed treatment and adherence. Physicians registered clinical data including prescribed medications. Two hundred fourteen patients (115 Crohn's disease/99 ulcerative colitis) were included. The most prescribed medications were oral mesalazine (56.5%) and immunomodulators (41.1%). Forty-three percent of patients admitted to occasionally forgetting to take their medication but only 7.5% of them did it voluntary. Oral mesalazine and azathioprine were the drugs with the poorest compliance, with nonadherence rates of 45% and 25% of the total prescribed doses, respectively. The only factor associated with a better adherence was a more complicated course of the disease-steroid dependency, steroid refractoriness, need for infliximab treatment, hospitalization, or surgery (P=.02). Twenty percent of patients admitted to self-medicating. An important proportion of patients with IBD admit to forget some doses of the prescribed medication in the setting of a specialized unit of a referral centre.

Differential features of colorectal cancers fulfilling Amsterdam criteria without involvement of the mutator pathway.

PURPOSE: Hereditary nonpolyposis colorectal cancer (HNPCC) is the commonest form of inherited colorectal cancer. Whereas it has been known that mismatch repair gene mutations are the underlying cause of HNPCC, an undetermined number of patients do not have these alterations. The main objectives of this study were to assess the relevance of clinically defined HNPCC patients without characteristic mutator pathway alterations and to identify their specific features. EXPERIMENTAL DESIGN: This was a prospective, population-based, cohort that included 1,309 newly diagnosed colorectal cancer patients. Demographic, clinical, pathologic data and tumor DNA from probands as well as a detailed family history were collected. Microsatellite analysis and MLH1, MSH2, and MSH6 immunohistochemistry were done. Germ line MLH1 and MSH2 mutational analysis was done in all patients with evidence of MMR alterations. RESULTS: Twenty-five patients (1.9%) fulfilled Amsterdam criteria of HNPCC but 15 (60%) of them did not have microsatellite instability and showed normal expression of MMR proteins. These patients presented mostly left-sided tumors without lymphocytic infiltrate; they were older, had fewer family members affected with colorectal or endometrial cancers, and more often fulfilled Amsterdam II criteria than HNPCC patients with microsatellite instability. Like unstable HNPCC patients, this group without mutator pathway alterations had a significant percentage of synchronous and metachronous adenomatous polyps and cancers. CONCLUSIONS: We define an important group of HNPCC families with specific features, no evidence of mismatch repair deficiency, and an autosomal dominant trait with a lesser penetrance than HNPCC with deficiency.

6-mercaptopurine in patients with inflammatory bowel disease and previous digestive intolerance of azathioprine.

OBJECTIVE: Azathioprine and 6-mercaptopurine are useful therapies in inflammatory bowel diseases. Despite their efficacy, their use is limited owing to treatment intolerance or toxicity in 10-15% of patients. It has been suggested that both drugs could be interchangeable. MATERIAL AND METHODS: All patients treated with 6-mercaptopurine because of previous digestive intolerance of azathioprine in four Spanish hospitals were reviewed. Tolerance of 6-mercaptopurine therapy was assessed. RESULTS: Fifteen patients (11 Crohn's disease, 4 ulcerative colitis) were included. Immunosuppressant therapy was prescribed for steroid-dependent disease in 13 cases, and for perianal disease in 2. Main symptoms of digestive intolerance were epigastric pain, nausea and vomiting, which developed within the first weeks of treatment. Acute pancreatitis was ruled out in all the cases. Five patients commenced 6-mercaptopurine immediately after azathioprine discontinuation and 7 patients within the first month. Eleven patients (73.3%) tolerated 6-mercaptopurine and reached the therapeutic goals; only two patients had to discontinue 6-mercaptopurine because of adverse effects. CONCLUSIONS: Treatment with 6-mercaptopurine is a safe alternative in patients with inflammatory bowel diseases and previous digestive intolerance of azathioprine.