Catalase inhibition can modulate the ability of peripheral blood T cells to undergo apoptosis in Crohn's disease.

Crohn's disease (CD) is a chronic relapsing inflammatory disorder in which defective apoptosis of mucosal T cells is postulated to produce sustained inflammation and reactive oxygen species accumulation. Whether CD T cells are intrinsically resistant to apoptosis or whether this resistance is acquired at the intestinal site needs to be clarified, as the cellular mechanisms modulate the impaired apoptosis in these cells. Here, we analysed peripheral blood T cells from patients naïve to specific CD treatment at the onset and from healthy controls. Non-activated freshly purified lymphocytes were cultured and submitted to in vitro protocols for activation (CD3/CD28 antibodies) and apoptosis (Fas antibody). Cells were analysed by flow cytometry. Caspases (3, 8, and 9) and catalase activity were measured; protein levels of bax, Bcl-2, and NF-kB were detected by western blotting, and cytokines by Luminex-based assays. The results showed that CD4 T cells from CD patients are less prone to apoptosis before they can migrate to the intestinal mucosa. Caspase-9, FasR, sIL-2Rα, IL-17A, IFNγ, IL-6, TNF-α, and IL-10 were shown to be significantly different in CD but not for the rest of the analysed biological elements. Catalase activity was significantly reduced in CD T cells, which was confirmed in ex vivo experiments in which catalase inhibition in T cells from healthy controls triggered apoptosis inhibition in a dose-dependent manner. In conclusion, apoptosis inhibition of CD T cells is a feature of these cells before they can migrate to the intestinal mucosa. Noteworthy, the impaired apoptosis of T cells can be directly influenced by catalase inhibition.

Real-world long-term effectiveness of ustekinumab in ulcerative colitis: results from a spanish open-label cohort.

OBJECTIVE: Ustekinumab was recently approved for the treatment of moderate-to-severe ulcerative colitis (UC). Although data from the UNIFI clinical trial are encouraging, real-world data assessing effectiveness and safety are scarce. The aim of this study was to assess the effectiveness, safety and pharmacokinetics of ustekinumab in a large cohort of refractory UC patients. METHODS: Multicenter observational study of UC patients who received ustekinumab for active disease. The Partial Mayo Score (PMS), endoscopic activity, C-reactive protein (CRP) and faecal calprotectin (FC) were recorded at baseline and at different time points. Demographic and clinical data, adverse events (AEs) and surgeries were documented. RESULTS: A total of 108 patients were analyzed from 4 referral Spanish hospitals. The clinical remission rates were 59%, 56.5%, 57% and 69% of patients at weeks 8, 16, 24 and 52, respectively. Normalization of FC was achieved in 39.6%, 41% and 51% at weeks 8, 24 and 52, respectively. CRP normalization was observed in 79%, 75% and 76.5% of patients at weeks 8, 24 and 52, respectively. Fewer previous anti-TNF agents and loss of response to anti-TNF were associated with clinical response and normalization of FC, respectively. AEs were observed in 5 patients, and 9 underwent colectomy. Ustekinumab persistence rates were 91%, 83% and 81% at 24, 48 and 96 weeks, respectively. CONCLUSIONS: Ustekinumab demonstrated, in the real-world setting, long-term effectiveness and a favorable safety profile in a cohort of refractory UC patients.

MicroRNA and granulocyte-monocyte adsorption apheresis combotherapy after inadequate response to anti-TNF agents in ulcerative colitis.

BACKGROUND: Ulcerative colitis (UC) is an inflammatory bowel disease characterized by chronic inflammation of the gastrointestinal tract, affecting millions of individuals throughout the world, and producing an impaired health-related quality of life. Granulocyte and monocyte apheresis (GMA) is a therapeutic option for UC management to induce remission by selective removal of activated leukocytes from bloodstream. Despite the knowledge of the important role of epigenetics in UC pathogenesis, and in the response to different treatments, nothing is known about the role of microRNAs in GMA therapy in UC patients. METHODS: Seven consecutively UC patients who started GMA in combo therapy with infliximab were recruited. Peripheral blood samples were taken before the apheresis session, at the start of the induction (S0) and at the end (S10). They were follow-up during the induction phase (10 sessions: 2 sessions for a week during 3 wk and 1 session for a week during 4 wk) of the treatment at a tertiary hospital (Hospital la Fe) and 6 mo after finishing the GMA induction therapy. MiRNA was extracted and analyzed by RT-PCR. R software and GraphPad were used. RESULTS: Clinical disease activity significantly decreased after induction therapy with GMA (median partial Mayo score 2 (IQR, 1-6) (P < .05). Fecal calprotectin value and CRP value significantly decreased after induction therapy. Five microRNAs modified their expression during GMA (unsupervised analysis): miR-342-3p, miR-215-5p, miR-376c-3p, miR-139-5p, and miR-150-5p. When a sub-analysis was performed in those patients who showed good response to apheresis treatment (n = 5), two microRNAs showed to be implicated: miR-215-5p and miR-365a-3p. These are preliminary but promising and novel results, as it is the first time, to our knowledge that microRNA profiles have been studied in the context of GMA treatment for IBD.

Evaluation of tolerance to mercaptopurine in patients with inflammatory bowel disease and gastrointestinal intolerance to azathioprine.

BACKGROUND: Thiopurines such as azathioprine (AZA) and mercaptopurine (MP) are commonly utilized to treat inflammatory bowel disease (IBD). Their use is frequently restricted due to gastrointestinal intolerance (GI). Previous retrospective studies have reported that AZA-intolerant patients may benefit from a switch to MP; yet the effectiveness of this strategy has not been prospectively evaluated. AIMS: To assess GI tolerance to MP in patients who are intolerant to AZA, and to identify clinical predictors of GI intolerance to AZA or MP. METHODS: A prospective, observational, single-cohort study was performed in 92 thiopurine-naïve IBD patients. They were started on a 50mg dose of AZA and escalated to 2.5mg/kg per day by week 2. Those with GI intolerance were rechallenged with a 50% dose of AZA, after which another dose escalation attempt was made. If symptoms persisted, they were switched to MP. RESULTS: Thirty (32.6%) of the recruited patients suffered from GI intolerance to AZA. Of these, 15 did not present recurrence of symptoms after rechallenge with lower doses. Of 15 intolerant patients, 14 were switched to MP. Within the MP cohort, 8 patients (57%) were also intolerant to MP, 5 (36%) had no symptoms, and 1 (7%) was lost to follow-up. Female gender was the only independent predictor of GI intolerance to AZA. CONCLUSIONS: Up to half of the AZA-intolerant patients tolerated a 50% dose rechallenge that was successfully escalated. A switch to MP was tolerated in over a third of cases whom rechallenge failed. Our strategy (challenge-rechallenge-switch) achieved an overall GI tolerance to thiopurines in most of the patients.

The Genetic Diversity and Dysfunctionality of Catalase Associated with a Worse Outcome in Crohn's Disease.

Chronic gut inflammation in Crohn's disease (CD) is associated with an increase in oxidative stress and an imbalance of antioxidant enzymes. We have previously shown that catalase (CAT) activity is permanently inhibited by CD. The purpose of the study was to determine whether there is any relationship between the single nucleotide polymorphisms (SNPs) in the CAT enzyme and the potential risk of CD associated with high levels of oxidative stress. Additionally, we used protein and regulation analyses to determine what causes long-term CAT inhibition in peripheral white mononuclear cells (PWMCs) in both active and inactive CD. We first used a retrospective cohort of 598 patients with CD and 625 age-matched healthy controls (ENEIDA registry) for the genotype analysis. A second human cohort was used to study the functional and regulatory mechanisms of CAT in CD. We isolated PWMCs from CD patients at the onset of the disease (naïve CD patients). In the genotype-association SNP analysis, the CAT SNPs rs1001179, rs475043, and rs525938 showed a significant association with CD (p < 0.001). Smoking CD patients with the CAT SNP rs475043 A/G genotype had significantly more often penetrating disease (p = 0.009). The gene expression and protein levels of CAT were permanently reduced in the active and inactive CD patients. The inhibition of CAT activity in the PWMCs of the CD patients was related to a low concentration of CAT protein caused by the downregulation of CAT-gene transcription. Our study suggests an association between CAT SNPs and the risk of CD that may explain permanent CAT inhibition in CD patients together with low CAT gene and protein expression.

The characteristics of the stricture, but not the ongoing treatment, could influence the outcome of endoscopic dilation in recurrent Crohn's disease.

AIM: Stricture is one of the main complications of Crohn's disease (CD). Among the main conservative therapeutic alternatives, endoscopic balloon dilation (EBD) of the strictures stands out, which can improve the symptoms and delay or even avoid the need for more surgeries. The main aim of this study was to evaluate the efficacy of the EBD in CD patients with post-surgical anastomotic strictures from a previous surgery. PATIENTS AND METHODS: An observational study of a cohort of 32 patients with CD who underwent EBD due to uncomplicated strictures at a tertiary hospital, since 2009. Demographic, clinical and disease variables, medical treatments and previous surgeries and types, analytical variables at the time of dilation, number of dilations, complications and need for subsequent surgery were collected by searching data in clinical records. RESULTS: Thirty-two patients were included, performing a total of 63 endoscopic dilations. A technical success of 63.5%, a therapeutic success by dilation of 58.75% and a therapeutic success per patient of 62.5% were achieved. Regarding complications, the percentage of post-dilation adverse events was 3.2% and post-dilation incidents were 4.8%. Thirty EBD did not need any medical treatment modification, 9 EBD remained untreated and 12 EBD required further surgery. The length of the strictures, but not the ongoing treatment, was the only statistically significant factor of therapeutic success by dilation and per patient. CONCLUSIONS: EBD seems a safe technique in short post-surgical strictures, can avoid the need for new surgery and prevents unnecessary immunosuppression in patients with CD anastomotic strictures.

Plasma Oncostatin M, TNF-α, IL-7, and IL-13 Network Predicts Crohn's Disease Response to Infliximab, as Assessed by Calprotectin Log Drop.

BACKGROUND: Cytokines emerge as possible biomarkers of response in Crohn's disease (CD). We aimed to determine the plasmatic cytokine profiles of active CD patients who started infliximab (IFX) treatment and their capacity to predict the response to IFX. METHODS: A total of 30 active CD patients receiving an induction therapy of IFX were enrolled in the study. Peripheral blood samples pretreatment were collected. Concentrations of 15 cytokines were measured by Luminex technology. Responses to IFX were evaluated by the drop in fecal calprotectin based on its logarithm-transformed values. A random forest (RF) predictive model was used for data analyses. RESULTS: Samples of 22 patients were analyzed. The RF model ranked the following cytokines as the top predictors of the response: tumor necrosis factor alpha (TNFα), interleukin (IL)-13, oncostatin M (OSM), and IL-7 (p < 0.005). Partial dependency plots showed that high levels of IL-13 pretreatment, low TNFα levels, and low IL-7 levels were associated with a favorable IFX response. Increased levels of OSM and TNFα predicted unfavorable responses to IFX. CONCLUSIONS: We here show that a log drop in calprotectin strongly correlates with clinical parameters and it can be proposed as a useful objective clinical response predictor. Plasma TNFα, IL-13, Il-7, and OSM network could predict CD response to IFX before induction therapy, as assessed by calprotectin log drop.

Idiopathic acute pancreatitis in patients with inflammatory bowel disease: A multicenter cohort study.

BACKGROUND: Idiopathic acute pancreatitis (IAP) in patients with inflammatory bowel disease (IBD) is not well characterized. Our purpose was to better understand this condition and its natural history. METHODS: Retrospective cohort study conducted at nine Spanish IBD referral centers. Patients with IBD and a first episode of acute pancreatitis (AP) between 1998 and 2018 were included. Patients with a previous episode of AP or a diagnosis of chronic pancreatitis were excluded. IAP and non-IAP were compared by multivariate logistic regression and survival analysis. RESULTS: We identified 185 patients with IBD (68.7% Crohn's disease) and a first episode of AP. Thirty-eight of those 185 (20.6%) fulfilled criteria for IAP. There were no severe cases of IAP. On multivariate analysis, AP before IBD diagnosis (21.1% vs. 3.4%, p = 0.04) and ulcerative colitis (52.6% vs. 23.1%, p = 0.002) were significantly more common in IAP. Further work-up was performed in 16/38 (42%) IAP patients, and a cause was identified in 6/16 (37.5%). Median time from AP to the end of follow-up was 6.3 years (3.1-10). Five-year risk of AP recurrence was significantly higher in IAP group (28% vs. 5.1%, log-rank p = 0.001), with a median time to first recurrence of 4.4 months (2.9-12.2). CONCLUSIONS: IAP represents the second cause of AP in patients with IBD. It is more frequent in ulcerative colitis, and presents a high risk of recurrence. Additional imaging work-up after a first episode of IAP in IBD patients is highly advisable, as it identifies a cause in more than one-third of cases.

Fecal Calprotectin Pretreatment and Induction Infliximab Levels for Prediction of Primary Nonresponse to Infliximab Therapy in Crohn's Disease.

INTRODUCTION: The association between infliximab (IFX) and fecal calprotectin (FC) levels on one hand, and the clinical and endoscopic response of patients with inflammatory bowel disease on the other, is well established. OBJECTIVE AND METHODS: To investigate the association between inflammatory biochemical parameters and serum concentrations of IFX during induction treatment with a primary nonresponse in a prospective cohort of Crohn's disease (CD) patients. RESULTS: Of the 35 patients included, 8 (22.8%) had primary nonresponse at the end of induction. Induction IFX levels were lower among primary nonresponders at weeks 6 and 14 (week 6: median IFX level 7.3 vs. 11.2 µg/mL, respectively, p = 0.090; week 14: median IFX level 1.5 vs. 4.7 µg/mL, respectively, p = 0.020). FC levels were higher in patients with primary nonresponse versus primary response at weeks 0, 6, and 14 (week 0: median FC level 1,830 vs. 410 µg/g, -respectively, p = 0.030; week 6: median FC level 1,150 vs. 230 µg/g, respectively, p = 0.074; week 14: median FC level 1,210 vs. 208 µg/g, respectively, p = 0.060). For the multivariate analysis, the median IFX level at week 14 and median FC level at week 0 were independently associated with primary nonresponse. A significant inverse correlation was determined between FC level at week 0 and IFX level at week 14 (Spearman's rho correlation, 0.440; p < 0.05). CONCLUSIONS: IFX levels (at week 14) and baseline FC levels could predict primary nonresponse after induction IFX therapy in patients with CD. A high baseline inflammatory load might modify the pharmacokinetic processes of anti-tumor necrosis factor drugs. Drug level monitoring and measurement of baseline inflammatory parameters could improve the efficacy of IFX in the induction therapy of patients with active CD.

Different Genetic Expression Profiles of Oxidative Stress and Apoptosis-Related Genes in Crohn's Disease.

BACKGROUND/AIMS: Increased oxidative stress and decreased immune cell apoptosis have been reported to be important factors in the pathogenesis of Crohn's disease (CD). Our aim was to characterize the genetic expression of molecules implicated in the regulation of oxidative stress and apoptosis in peripheral white mononuclear cells of 18 healthy volunteers (controls) and 20 patients at the onset of CD (active CD [aCD]): 10 who achieved remission (inactive CD [iCD]) and 10 who did not present a complete and deep response to treatment (aCD-T). METHODS: mRNA expression was measured by the Agena MassARRAY quantitative gene expression analysis application. The genes analyzed were Fas-receptor (FASR), Fas-ligand (FASL), signal transducer and activator of transcription 1 (STAT1), nuclear factor kappa-light-chain--enhancer of activated B cells (NFKB1), apoptosis signal-regulating kinase 1 (ASK1), serine/threonine-protein kinase H1 (PSKH1), ATP-binding cassette sub-family B1 (ABCB1) and peptidylprolyl isomerase D (PPID). RESULTS: During a CD flare, we found specific upregulated expression of the genes STAT1 and PSKH1, whereas ABCB1 and FASL were downregulated. In the patients with iCD, FASR and NFKB1 were upregulated. The expression levels of NFKB1, STAT1 and ABCB1 did not show any difference in patients with aCD at the onset of the disease and after treatment (aCD-T). The expression levels of PPID and ASK1 did not show any differences in the patients with aCD, iCD and the controls. We have also reviewed the cellular function and role of these genes in CD. CONCLUSIONS: These findings contribute to improving the understanding of the pathogenesis of CD and highlight potential genes involved.

Withdrawal of Azathioprine in Inflammatory Bowel Disease Patients Who Sustain Remission: New Risk Factors for Relapse.

BACKGROUND: The benefits of immunosuppressants for sustaining remission and preventing flares of IBD are well known. However, optimal timing for withdrawal has not been determined. AIMS: The objective of this study was to calculate the risk of relapse and predictors after withdrawal of azathioprine (AZA) monotherapy in patients who sustain deep remission. METHODS: This was a multicenter observational study of patients with IBD in remission whose immunosuppressant had been withdrawn. We recorded demographic variables, disease data, laboratory values, and the results of imaging tests performed at withdrawal and, in patients who relapsed, time to relapse and the efficacy of reintroducing the drug. RESULTS: Ninety-five patients were included (35 UC and 60 CD). The mean duration of AZA treatment was 87 and 77 months for UC and CD, respectively. Endoscopic remission was evaluated in 23 patients with UC and 35 with CD. After AZA withdrawal, 91% patients with UC and 67% with CD received high doses of salicylates. A total of 26 patients relapsed. The cumulative relapse rate at 5 years was 46% for CD and UC. AZA was reintroduced in 19 patients, of whom 14 responded. Predictors of relapse were corticosteroid dependence, early introduction of AZA (CD), and late introduction of AZA (UC). CONCLUSIONS: Almost half of the patients in whom AZA was withdrawn were in remission at 5 years. The candidates for withdrawal could be better identified based on corticosteroid dependence, previous surgery, timing of initiation, and indication for AZA.

Inflammatory bowel disease in patients over the age of 70 y. Does the disease duration influence its behavior?

INTRODUCTION: The fastest growing segment of our population is that of people above 70 years of age. Elderly patients with IBD exhibit several specific problems. Our objective was to evaluate the clinical course, the side effects of the treatments and the need for surgery of elderly patients, regardless of the age of onset. MATERIALS AND METHODS: This was a cross-sectional study wherein retrospective data were collected from multiple centers from seven hospitals within the Valencia metropolitan area. Data were collected on patients older than 70 y with inflammatory bowel disease. RESULTS: We identified a total of 331 patients older than 70 years of age (5.3% of patients monitored at our centers). The mean age at the time of the study was 77.34 y (±5.39). Mesalamine were the most frequently used medications. Corticosteroids were used in 66% of the patients. However, the use of corticosteroids and biologics was less probable in older patients (OR 0.96, p = .06). The longer the disease progressed, the more immunosuppressive medications were used (OR 1.3, p = .052). Neoplasms appeared in 41 patients (13%). Of the 36 patients with tumors that appeared after the onset of the disease, 20 patients had not been treated with immunomodulators or biologics. CONCLUSIONS: Mesalamine was the most frequently used medication. There is no increased risk of tumors regarding the medications used. The use of immunosuppressive medications is more prevalent with longer disease progression times, although with a high rate of adverse events.

Adsorptive granulocyte/monocyte apheresis use in severe ulcerative colitis and determination of changes in plasma cytokines.

Despite controversy regarding the use of granulocyte/monocyte adsorption (GMA) in inflammatory bowel disease, some studies have shown favorable outcomes when it is used in steroid-dependent patients with ulcerative colitis (UC). The mechanisms responsible for such outcomes are not well characterized, but changes in immune cell populations and cytokine levels have been suggested to play an important role. We report the cases of 3 patients with chronically active severe UC who underwent GMA due to an inadequate response to standard and rescue therapy, as well as changes to their plasma cytokine profile. All the patients presented severe UC that was only partially responsive to various immunosuppressive drugs, and they were, therefore, referred for colectomy; however, all 3 refused this option, which led to the compassionate use of GMA as a last therapeutic resort. Following GMA treatment, rapid normalization of the clinical, endoscopic and laboratory parameters was observed in all the patients. Despite having achieved a good response, most cytokines remained at high concentrations after GMA, and only two, IL-6 and IL-8, showed a clear decrease throughout the GMA sessions. In view of this outcome, we hypothesize that GMA can help to lower the inflammatory load, thereby enhancing the effect of biologic drugs. To confirm this hypothesis and explore further indications for GMA, we propose the need for research directed toward the characterization of immune cell populations and their specific cytokine production rather than global cytokine assessment.

Vedolizumab, an option in patients with inflammatory bowel disease intolerant to thiopurines and refractory to biological agents. / Vedolizumab, una opción en pacientes con enfermedad inflamatoria intestinal intolerantes a tiopurinas y refractarios a biológicos.

Vedolizumab (VDZ), a human monoclonal antibody that binds specifically to α4ß7-integrin, and is approved for the treatment of Crohn's disease (CD) and ulcerative colitis (UC), has demonstrated its efficacy in controlled clinical trials. OBJECTIVE: To describe a population treated with VDZ and to evaluate its long-term efficacy and safety in clinical practice. METHODS: An observational and multicentre study was carried out on patients with inflammatory bowel disease treated with VDZ for at least one year. An evaluation was performed on the activity indices, faecal calprotectin and C-reactive protein levels, hospital admissions, surgeries, and adverse events. RESULTS: A total of 73 patients were analysed (43 UC and 30 CD). More than one anti-TNF and more than one immunosuppressive was previously used by 74 and 23%, respectively, of UC patients, and 90 and 37%, respectively of CD patients. VDZ was stopped in 17 (23%) patients, 10 UC and 7 CD, due to a lack or loss of response before the first year, or due to adverse events. An intensification of the dose was required in 26 (63%) UC, and 16 (53%) CD patients. At 6 months, 70 and 42% of UC patients, and 80 and 43% of CD patients achieved a clinical response and remission, respectively. At one year, 58 and 35% of UC patients and 47 and 43% of CD patients, maintained the clinical response and remission, respectively. The C-reactive protein decreased significantly in both CD and UC patients. However, the decrease in faecal calprotectin was only achieved during follow-up in UC, but not in CD patients. Eight patients with CD that had been treated previously with ustekinumab avoided surgery at one year. A colectomy was performed on 8 (18.6%) UC patients, and 4 (13.3%) CD patients needed surgery. Six patients (8%) (5 UC and 1 CD) had adverse events. The concomitant use of corticosteroids or immunomodulators did not increase the efficacy. Those with a higher number of previous anti-TNF treatments showed less remissions in UC and responses in CD. CONCLUSIONS: After one year of VDZ, a clinical response and remission was induced in a considerable percentage of patients refractory to different biological or immunosuppressive therapies. VDZ can be considered as an alternative in those intolerant to immunosuppressives, with few adverse events.

Recommendations of the Spanish Working Group on Crohn's Disease and Ulcerative Colitis (GETECCU) and the Association of Crohn's Disease and Ulcerative Colitis Patients (ACCU) in the management of psychological problems in Inflammatory Bowel Disease patients. / Recomendaciones del Grupo Español de Trabajo en Enfermedad de Crohn y Colitis Ulcerosa (GETECCU) y de la Confederación de Asociaciones de Enfermedad de Crohn y Colitis Ulcerosa (ACCU) para el manejo de los aspectos psicológicos en la enfermedad inflamatoria intestinal.

AIMS: To establish recommendations for the management of psychological problems affecting patients with inflammatory bowel disease (IBD). METHODS: A meeting of a group of IBD experts made up of doctors, psychologists, nurses and patient representatives was held. The following were presented: 1) Results of a previous focal group, 2) Results of doctor and patient surveys, 3) Results of a systematic review of tools for detecting anxiety and depression. A guided discussion was then held about the most important psychological and emotional problems associated with IBD, appropriate referral criteria and situations to be avoided. The validated instrument most applicable to clinical practice was selected. A recommendations document and a Delphi survey were designed. The survey was sent to the group and to a scientific committee of the GETECCU group in order to establish the level of agreement with these recommendations. RESULTS: Fifteen recommendations were established linked to 3 key processes: 1) What steps should be taken to identify psychological problems at an IBD appointment; 2) What are the criteria for referring patients to a mental health specialist; 3) How to approach psychological problems. CONCLUSIONS: Resources should be made available to healthcare professionals so that they can treat these problems during consultations, identify the disorders which could affect the clinical course of the disease and determine their impact on the patient's life in order that these can be treated and followed up by the most suitable professional. These recommendations could serve as a basis for redesigning IBD services or processes and as justification for the training of healthcare personnel.

Correlation between fecal calprotectin and inflammation in the surgical specimen of Crohn's disease.

BACKGROUND: An accurate assessment of the inflammatory activity is crucial to establish the most appropriate treatment in Crohn's disease (CD). The present study aimed to evaluate the utility of preoperative fecal calprotectin (FC) measurement in small bowel CD and its relationship with inflammatory activity in surgical pathology specimens. METHODS: This was a prospective observational study including all the patients with small bowel CD operated on at our center between March 2011 and September 2013. Preoperative laboratory and stool tests were performed. A meticulous exploration of entire small bowel was performed during surgery, and the resected bowel (or a sample of whole intestinal wall, if strictureplasty) was submitted for pathologic analyses. Chiorean's score was used to grade pathologic features (inflammation or fibrosis). In case of multiple lesions, the most inflammatory component was considered. RESULTS: Thirty-eight consecutive patients were included in the study, and 81 small bowel lesions were identified. Among inflammatory markers, only FC was significantly associated with the degree of histologic inflammation in the surgical specimen (P < 0.003). FC reflected histologic inflammatory activity with an area under the receiver-operating characteristic curve of 0.85 (CI: 0.70-0.99; P < 0.001). A cutoff value of 170 µg/g had 81% sensitivity and 85% specificity for diagnosis of moderate or severe inflammation. Ordinal regression analysis showed the probability of a greater or lesser degree of inflammation based on the value of preoperative FC. CONCLUSIONS: FC is an excellent biomarker of inflammatory activity in small bowel CD as it correlates with histologic inflammation in the surgical specimen.

Immunological Mechanisms of Adsorptive Cytapheresis in Inflammatory Bowel Disease.

Ulcerative colitis and Crohn's disease are the two main forms of inflammatory bowel disease (IBD). The study of immunological pathways involved in the onset of IBD is of fundamental importance to identify potential biological markers of disease activity and specific targets for therapy. Removing excess and activated circulating leukocytes with adsorptive cytapheresis has been shown to be a potentially effective treatment for patients with an inflamed bowel. Adsorptive cytapheresis is a non-pharmacological approach for active IBD, in which known sources of inflammatory cytokines such as activated myeloid lineage leucocytes are selectively depleted from the circulatory system. The decrease in inflammatory load caused by removing these cells is thought to enhance drug therapy and thereby promote disease remission. The benefit of cytapheresis appears to rest upon its ability to reduce levels of certain immune cell populations; however, whether this depletion results in further changes in lymphocyte populations and cytokine production needs further clarification. In this review, we aim to summarize existing evidence on the role of cytapheresis in patients with IBD, its effect on cytokine levels and cellular populations, and to discuss its potential impact on disease activity.