Accuracy of ChatGPT in Common Gastrointestinal Diseases: Impact for Patients and Providers

Since its release in 2022, Chat Generative Pre-Trained Transformer (ChatGPT) became the most rapidly expanding consumer software application in history,1 and its role in medicine is underscored by its potential to enhance patient education and physician-patient communication. Previous studies in gastroenterology and hepatology have focused primarily on the earlier Generative Pre-Trained Transformer 3 (GPT-3) model, with none investigating ChatGPT's ability to generate supportive references for its responses, or its applicability as a physician educational tool.2-6 Our study evaluated the accuracy of the more recent ChatGPT, powered by GPT-4, in addressing frequently asked questions by patients on irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), colonoscopy and colorectal cancer (CRC) screening, questions on CRC screening from a physician perspective, and reference generation and suitability.

Novel Genetic Risk Variants and Clinical Predictors Associated With Primary Sclerosing Cholangitis in Patients With Ulcerative Colitis

INTRODUCTION

Patients with ulcerative colitis (UC) who are likely to have primary sclerosing cholangitis (PSC) should be identified because PSC can influence UC clinical behavior and outcomes.The aim of this study was to establish a model incorporating clinical and genetic risk predictors that identifies patients with UC at risk of developing PSC.

METHODS

We conducted a retrospective case-control study. Inflammatory bowel disease cohorts from multiple institutions were used as discovery and replicate datasets. Quality control criteria, including minor allele frequency, call rates, Hardy-Weinberg equilibrium, cryptic relatedness, and population stratification (through principal components), were used. Discriminative accuracy was evaluated with area under the receiver operating characteristic curve.

RESULTS

Fifty-seven of 581 patients (9.8%) with UC had PSC. Multivariate analysis showed that patients with UC-PSC had more extensive disease (odds ratio [OR], 5.42; P = 1.57E-04), younger diagnosis age (younger than 20 years; OR, 2.22; P = 0.02), and less smoking (OR, 0.42; P = 0.02) than those with UC. After linkage disequilibrium pruning and multivariate analyses, 3 SNPs (rs3131621 at 6p21.33; rs9275596 and rs11244 at 6p21.32) at the HLA region were found associated with a 2- to 3-fold increased risk of PSC. Our model demonstrated good discriminatory power (area under the receiver operating characteristic curve, 88%).

DISCUSSION

Three variants in HLA (6p21.3) region significantly distinguished patients with UC-PSC from patients with UC alone. Once further validated in an independent large cohort, our model could be used to identify patients with UC at risk of PSC, and it could also help guide disease management.

A novel murine model of pyoderma gangrenosum reveals that inflammatory skin-gut crosstalk is mediated by IL-1β-primed neutrophils

Pyoderma gangrenosum (PG) is a debilitating skin condition often accompanied by inflammatory bowel disease (IBD). Strikingly, ~40% of patients that present with PG have underlying IBD, suggesting shared but unknown mechanisms of pathogenesis. Impeding the development of effective treatments for PG is the absence of an animal model that exhibits features of both skin and gut manifestations. This study describes the development of the first experimental drug-induced mouse model of PG with concomitant intestinal inflammation. Topical application of pyrimidine synthesis inhibitors on wounded mouse skin generates skin ulcers enriched in neutrophil extracellular traps (NETs) as well as pro-inflammatory cellular and soluble mediators mimicking human PG. The mice also develop spontaneous intestinal inflammation demonstrated by histologic damage. Further investigations revealed increased circulating low density IL-1β primed neutrophils that undergo enhanced NETosis at inflamed tissue sites supported by an increase in circulatory citrullinated histone 3, a marker of aberrant NET formation. Granulocyte depletion dampens the intestinal inflammation in this model, further supporting the notion that granulocytes contribute to the skin-gut crosstalk in PG mice. We anticipate that this novel murine PG model will enable researchers to probe common disease mechanisms and identify more effective targets for treatment for PG patients with IBD.

Long-term Outcomes of Perianal Fistulas in Pediatric Crohn's Disease

BACKGROUND

Approximately 30% of Crohn's disease-related perianal fistulas heal in the adult population with conventional medical and surgical interventions. This healing rate remains unknown in pediatric patients.

OBJECTIVE

This study aimed to determine the healing rate of pediatric perianal Crohn's fistulas and identify factors associated with healing.

DESIGN

Retrospective case series.

SETTING

A quaternary referral center.

PATIENTS

Patients aged <18 years with a Crohn's perianal fistula, seen between January 1, 1991, and August 1, 2021, were included in the study.

INTERVENTIONS

Multivariable logistic regression to identify factors independently associated with perianal fistula healing.

MAIN OUTCOME MEASURES

Healing of Crohn's perianal fistula at the date of last clinical encounter, defined as the clinical note reporting a healed fistula or normal perianal examination.

RESULTS

A total of 91 patients aged <18 years with a Crohn's disease-related perianal fistula were identified (59% female, 76% white). The mean (SD) age at Crohn's diagnosis was 12 (±4) years. The mean follow-up after Crohn's diagnosis was 10 (±7) years. Overall, 89% of patients had a perianal fistula, 2% had an anovaginal fistula, and 10% had an ileal pouch-associated fistula. Patients underwent a median (interquartile range) of 2 (1-5) operations. A seton was placed in 60% of patients, 47% underwent abscess drainage, and 44% underwent fistulotomy or fistulectomy. Fistula healing occurred in 71% of patients over a median of 1.3 (0.4-2.5) years. Seven patients (7%) underwent proctectomy, and 3 (3%) underwent ileal pouch excision. After multivariable adjustment, younger age at diagnosis of perianal fistula was associated with an increased likelihood of healing (OR 0.56 for each increased year; 95% CI, 0.34-0.92).

LIMITATIONS

Retrospective, single institution.

CONCLUSIONS

Over two-thirds of fistulas heal in pediatric Crohn's disease patients with conventional surgical and medical intervention. Younger age at fistula development is associated with an increased likelihood of healing. See Video Abstract at http://links.lww.com/DCR/C185 .

RESULTADOS A LARGO PLAZO DE LAS FSTULAS PERIANALES EN LA ENFERMEDAD DE CROHN EN PACIENTES PEDITRICOS

ANTECEDENTES:Aproximadamente el 30% de las fístulas perianales relacionadas con la enfermedad de Crohn se curan en la población adulta con intervenciones médicas y quirúrgicas convencionales. Esta tasa de curación sigue siendo desconocida en pacientes pediátricos.OBJETIVO:Determinar la tasa de curación de las fístulas de Crohn perianales en población pediátrica e identificar los factores asociados con la curación.DISEÑO:Serie de casos retrospectiva.ESCENARIO:Un centro de referencia cuaternario.PACIENTES:Pacientes menores de 18 años con fístula(s) perianal(es) por enfermedad de Crohn, atendidos entre el 1 de enero de 1991 y el 1 de agosto de 2021.INTERVENCIONES:Regresión logística multivariable para identificar factores asociados de forma independiente con la cicatrización de la fístula perianal.PRINCIPALES MEDIDAS DE RESULTADO:Curación de la fístula perianal de Crohn en la fecha del último encuentro clínico, definida como la nota clínica que informa una fístula curada o un examen perianal normal.RESULTADOS:Se identificó un total de 91 pacientes <18 años de edad con una fístula perianal relacionada con la enfermedad de Crohn (59% mujeres, 76% blancos). La edad media (DE) al diagnóstico de Crohn fue de 12 (±4) años. El seguimiento medio tras el diagnóstico de Crohn fue de 10 (±7) años. En general, el 89 % de los pacientes tenía fístula perianal, el 2 % tenía fístula anovaginal y el 10 % de los pacientes tenía fístula asociada a reservorio ileal. Los pacientes fueron sometidos a una mediana (RIC) de 2 (1-5) operaciones. En el 60% de los pacientes se colocó sedal, en el 47% se drenó el absceso y en el 44% se realizó fistulotomía o fistulectomía. La curación de la fístula se produjo en el 71% de los pacientes durante una mediana de 1,3 (0,4-2,5) años. Siete pacientes (7%) se sometieron a proctectomía y 3 (3%) se sometieron a escisión del reservorio ileal. Después del ajuste multivariable, la edad más joven en el momento del diagnóstico de la fístula perianal se asoció con una mayor probabilidad de curación (OR 0,56 por cada año de aumento, IC del 95%, 0,34-0,92).LIMITACIONES:Retrospectivo, institución única.CONCLUSIONES:Más de dos tercios de las fístulas se curan en pacientes pediátricos con enfermedad de Crohn con intervención médica y quirúrgica convencional. Una edad más joven en el momento del desarrollo de la fístula se asocia con una mayor probabilidad de curación. Consulte Video Resumen en http://links.lww.com/DCR/C185 . (Traducción--Dr. Felipe Bellolio ).

Computable Phenotype of a Crohn's Disease Natural History Model

BACKGROUND

Analytic tools to study important clinical issues in complex, chronic diseases such as Crohn's disease (CD) include randomized trials, claims database studies, or small longitudinal epidemiologic cohorts. Using natural language processing (NLP), we sought to define the computable phenotype health state of pediatric and adult CD and develop patient-level longitudinal histories for health outcomes.

METHODS

We defined 6 health states for CD using a subjective symptom-based assessment (symptomatic/asymptomatic) and an objective disease state assessment (active/inactive/no testing). Gold standard for the 6 health states was derived using an iterative process during review by our CD experts. We calculated the transition probabilities to estimate the time to transitions between the various health states using nonparametric Kaplan-Meier estimation and a Markov model. Finally, we determined a standard utility measure from clinical patients assigned to different health states.

RESULTS

The NLP computable phenotype health state model correctly ascertained the objective test results and symptoms 96% and 85% of the time, respectively, based on a blinded chart evaluation. In our model, >25% of patients who begin as asymptomatic/active transition to symptomatic/active over the following year. For both adult and pediatric CD health states, the utility assessments of a symptomatic/inactive health state closely resembled a symptomatic/active health state.

CONCLUSIONS

Our methodology for a computable phenotype health state demonstrates the application of real-world data to define progression and optimal management of a chronic disease such as CD. The application of the model has the potential to lead to a better understanding of the true impact of a therapeutic intervention and can provide long-term cost-effectiveness analyses for a new therapy.

HIGHLIGHTS

Using natural language processing, we defined the computable phenotype health state of Crohn's disease and developed patient-level longitudinal histories for health outcomes.Our methodology demonstrates the application of real-world data to define the progression of a chronic disease.The application of the model has the potential to provide better understanding of the true impact of a new therapy.

Association of cancer with comorbid inflammatory conditions and treatment in patients with Lynch syndrome

BACKGROUND

Individuals with Lynch syndrome (LS) and hereditary non-polyposis colorectal cancer (HNPCC) are at increased risk of both colorectal cancer and other cancers. The interplay between immunosuppression, a comorbid inflammatory condition (CID), and HNPCC on cancer risk is unclear.

AIM

To evaluate the impact of CIDs, and exposure to monoclonal antibodies and immunomodulators, on cancer risk in individuals with HNPCC.

METHODS

Individuals prospectively followed in a hereditary cancer registry with LS/HNPCC with the diagnosis of inflammatory bowel disease or rheumatic disease were identified. We compared the proportion of patients with cancer in LS/HNPCC group with and without a CID. We also compared the proportion of patients who developed cancer following a CID diagnosis based upon exposure to immunosuppressive medications.

RESULTS

A total of 21 patients with LS/HNPCC and a CID were compared to 43 patients with LS/HNPCC but no CID. Cancer occurred in 84.2% with a CID compared to 76.7% without a CID (P = 0.74) with no difference in age at first cancer diagnosis 45.5 ± 14.6 vs 43.8 ± 7.1 years (P = 0.67). LS specific cancers were diagnosed in 52.4% with a CID vs 44.2% without a CID (P = 0.54). Nine of 21 (42.9%) patients were exposed to biologics or immunomodulators for the treatment of their CID. Cancer after diagnosis of CID was seen in 7 (77.8%) of exposed individuals vs 5 (41.7%) individuals unexposed to biologics/immunomodulators (P = 0.18). All 7 exposed compared to 3/5 unexposed developed a LS specific cancer. The exposed and unexposed groups were followed for a median 10 years and 8.5 years, respectively. The hazard ratio for cancer with medication exposure was 1.59 (P = 0.43, 95%CI: 0.5-5.1).

CONCLUSION

In patients with LS/HNPCC, the presence of a concurrent inflammatory condition, or use of immunosuppressive medication to treat the inflammatory condition, might not increase the rate of cancer occurrence in this limited study.

Mesenteric Excision and Exclusion for Ileocolic Crohn's Disease: Feasibility and Safety of an Innovative, Combined Surgical Approach With Extended Mesenteric Excision and Kono-S Anastomosis

INTRODUCTION

Ileocolic resection for Crohn's disease traditionally does not include a high ligation of the ileocolic pedicle, and most commonly is performed with a stapled side-to-side ileocolic anastomosis. The mesentery has recently been implicated in the pathophysiology of Crohn's disease. Two techniques have been developed and are associated with reduced postoperative recurrence: the Kono-S anastomosis that excludes diseased mesentery and extended mesenteric excision that resects diseased mesentery. We aimed to assess the technical feasibility and safety of a novel combination of techniques: mesenteric excision and exclusion.

TECHNIQUES

This initial report is a single-center descriptive study of consecutive adults who underwent mesenteric excision and exclusion for primary or recurrent ileocolic Crohn's disease from September 2020 to June 2021. Medication exposure and endoscopic balloon dilation before surgery were recorded. Phenotype was classified using the Montreal Classification. Thirty-day outcomes were reported. A video of the mesenteric excision and exclusion including the Kono-S anastomosis is presented.

RESULTS

Twenty-two patients with ileocolic Crohn's disease underwent mesenteric excision and exclusion: 100% had strictures, 59% had fistulas, 81% were on biologics, and 27% had previous ileocolic resection(s). Seventy-two percent underwent laparoscopic procedures, a mesenteric defect was closed in 86%, omental flaps were fashioned in 77%, and 3 patients were diverted. Median operative time was 175 minutes. Median postoperative stay was 4 days. At 30 days, there were 2 readmissions for reintervention: 1 seton placement and 1 percutaneous drainage of a sterile collection. There were no cases of intra-abdominal sepsis or anastomotic leak.

CONCLUSIONS

Mesenteric excision and exclusion represents an innovative, progressive, and promising approach that appears to be highly feasible and safe. Further study is warranted to determine if mesenteric excision and exclusion is associated with reduced postoperative recurrence of ileocolic Crohn's disease.

Differences in Biologic Utilization and Surgery Rates in Pediatric and Adult Crohn's Disease: Results From a Large Electronic Medical Record-derived Cohort

BACKGROUND AND AIMS

Crohn's disease (CD) is a chronic illness that affects both the pediatric and adult populations with an increasing worldwide prevalence. We aim to identify a large, single-center cohort of patients with CD using natural language processing (NLP) in combination with codified data and extract surgical rates and medication usage from the electronic medical record (EMR).

METHODS

Patients with CD were identified from the entire Cleveland Clinic EMR using ICD codes and CD-specific terms identified by NLP to fit a logistic regression model. Cohorts were developed for pediatric-onset (younger than 18 years) and adult-onset (18 years and older) CD. Surgeries were identified using current procedural terminology (CPT) codes and NLP. Crohn's disease-related medications were extracted using physician orders in the EMR.

RESULTS

Patients with pediatric-onset (n = 2060) and adult-onset (n = 4973) CD were identified from 2000 to 2017 with a positive predictive value of 98.5%. Rate of CD-related abdominal surgery over time was significantly higher in adult-onset compared with pediatric-onset CD (10-year surgery rate 49.9% vs 37.7%, respectively; P < 0.001). Treatment with biologics was significantly higher in pediatric vs adult-onset CD cohorts (63.6% vs 49.2%; P < 0.001). The overall rate of CD-related abdominal surgery was significantly higher in those who received <6 months of a biologic compared with ≥6 months of a biologic for both cohorts (pediatric 64.1% vs 39.1%, P ≤ 0.001; adult 69.3% vs 56.5%, P ≤ 0.001). Additionally, 60.9% in pediatric-onset CD and 43.5% in adult-onset CD treated with ≥6 months of biologic therapy have not required abdominal surgery. On multivariable analysis, perianal surgery was a significant risk factor for abdominal surgery in both cohorts.

CONCLUSION

We used a combination of codified and NLP data to establish the largest, North American, single-center EMR cohort of pediatric- and adult-onset CD patients and determined that biologics are associated with lower rates of surgery over time, potentially altering the natural history of the disease.

Malignancy risk in individuals with familial adenomatous polyposis receiving biologics and immunomodulators

Clinicians may be hesitant to prescribe biologics or immunomodulators to individuals with familial adenomatous polyposis (FAP) and comorbid inflammatory disease (CID) because of increased cancer risk. Our aim was to compare the risk of malignancy in FAP individuals with inflammatory bowel (IBD) and/or rheumatic disease that received biologics/immunomodulators to those who did not. Individuals with FAP and CID were included in the study. We compared the incidence of cancer between individuals exposed to biologics/immunomodulators compared to unexposed from the date of diagnosis of comorbid disease till last follow up or death. Hazard ratio (HR) for cancer was computed using Cox regression model and compared by exposure status to biologic/immunomodulators. 25 individuals with FAP and a comorbid inflammatory disease were identified including 9 (36%) with IBD and 16 (64%) with rheumatic disease. 14 (56%) were exposed to a biologic and or immunomodulator. Median duration of biologic/immunomodulator exposure was 48 (2-180) months. 3 (21.4%) in the exposed group compared to 1 (9.1%) in the unexposed group developed cancer with a HR for exposure of 1.92 (CI 0.2-18.5, p = 0.57). Median duration of follow up after the diagnosis of inflammatory disease was 10 (5.5-17.0) years in the exposed and 6 (3.0-15.0) years in the unexposed group. In the exposed group, 1 patient developed gastric and 2 developed colon cancer. One unexposed patient developed medullary thyroid cancer. There is a possible trend of more cancers in the group that received biologics/immunomodulators-but given the small number of patients and p-value, there may be no difference at all. This preliminary finding warrants study in a larger cohort.

Gastrointestinal manifestations of COVID-19

Gastrointestinal (GI) symptoms are seen in patients with COVID-19. The prevalence could be as high as 50%, but most studies show ranges from 16% to 33%. Presenting with GI symptoms increases the risk of testing positive for SARs-CoV-2. Approximately 50% of patients with COVID-19 have detectable virus in their stool. Having GI symptoms has been associated with more severe disease. Management of GI symptoms is mainly supportive. Healthcare providers should be aware of the GI manifestations of COVID-19 and perform SARS-CoV-2 testing for patients presenting with digestive changes, especially in those with respiratory symptoms.

Hypoalbuminaemia, Not Biologic Exposure, Is Associated with Postoperative Complications in Crohn's Disease Patients Undergoing Ileocolic Resection

BACKGROUND

There are limited data on the postoperative outcomes in Crohn's disease patients exposed to preoperative ustekinumab or vedolizumab. We hypothesised that preoperative biologic use in Crohn's disease is not associated with postoperative complications after ileocolic resection.

METHODS

Crohn's disease patients who underwent ileocolic resection over 2009-2019 were identified at a large regional health system. Preoperative biologic use within 12 weeks of surgery was categorised as no biologic, anti-tumour necrosis factor, vedolizumab, or ustekinumab. The primary endpoint was 90-day intra-abdominal septic complication. Risk factors included preoperative medical therapies, demographics, disease characteristics, laboratory values, and surgical approach. Regression models assessed the association of biologic use with intra-abdominal septic complication.

RESULTS

A total of 815 Crohn's disease patients who underwent an ileocolic resection were included [62% no biologic, 31.4% anti-tumour necrosis factor, 3.9% vedolizumab, 2.6% ustekinumab]. Primary anastomosis was performed in 85.9% of patients [side-to-side 48.8%, end-to-side 26%, end-to-end 25%] in primarily a stapled [77.2%] manner. Minimally invasive approach was used in 41.4%. The 90-day postoperative intra-abdominal sepsis rate of 810 patients was 12%, abscess rate was 9.6%, and anastomotic leak rate was 3.2%. Multivariable regression modelling controlling for confounding variables demonstrated that preoperative biologic use with anti-tumour necrosis factor [p = 0.21], vedolizumab [p = 0.17], or ustekinumab [p = 0.52] was not significantly associated with intra-abdominal septic complication. Preoperative albumin < 3.5 g/dl was independently associated with intra-abdominal septic complication (odds ratio [OR] 1.76 [1.03, 3.01]).

CONCLUSIONS

In Crohn's disease patients undergoing ileocolic resection, preoperative biologics are not associated with 90-day postoperative intra-abdominal septic complication. Preoperative biologic exposure should not delay necessary surgery.

Adipokine Resistin Levels at Time of Pediatric Crohn Disease Diagnosis Predict Escalation to Biologic Therapy

BACKGROUND

Hypertrophy of visceral adipose tissue (VAT) is a hallmark of Crohn disease (CD). The VAT produces a wide range of adipokines, biologically active factors that contribute to metabolic disorders in addition to CD pathogenesis. The study aim was to concomitantly evaluate serum adipokine profiles and VAT volumes as predictors of disease outcomes and treatment course in newly diagnosed pediatric patients with CD.

METHODS

Pediatric patients ages 6 to 20 years were enrolled, and their clinical data and anthropometric measurements were obtained. Adipokine levels were measured at 0, 6, and 12 months after CD diagnosis and baseline in control patients (CP). The VAT volumes were measured by magnetic resonance imaging or computed tomography imaging within 3 months of diagnosis.

RESULTS

One hundred four patients undergoing colonoscopy were prospectively enrolled: 36 diagnosed with CD and 68 CP. The serum adipokine resistin and plasminogen activator inhibitor (PAI)-1 levels were significantly higher in patients with CD at diagnosis than in CP. The VAT volume was similar between CD and CP. Baseline resistin levels at the time of diagnosis in patients with CD who were escalated to biologics was significantly higher than in those not treated using biologic therapy by 12 months (29.8 ng/mL vs 13.8 ng/mL; P = 0.004). A resistin level of ≥29.8 ng/mL at the time of diagnosis predicted escalation to biologic therapy in the first year after diagnosis with a specificity of 95% (sensitivity = 53%; area under the curve = 0.82; P = 0.015 for model with log-scale). There was a significantly greater reduction in resistin (P = 0.002) and PAI-1 (P = 0.010) at the 12-month follow-up in patients on biologics compared with patients who were not treated using biologics.

CONCLUSIONS

Serum resistin levels at diagnosis of pediatric CD predict the escalation to biologic therapy at 12 months, independent of VAT volumes. Resistin and PAI-1 levels significantly improved in patients with CD after treatment using biologics compared with those not on biologics. These results suggest the utility of resistin as a predictive biomarker in pediatric CD.

Systematic review: medical therapy for fibrostenosing Crohn's disease

BACKGROUND

Medical therapy and/or endoscopic balloon dilation with intralesional therapies are options for the treatment of small bowel fibrostenotic Crohn's disease (CD).

AIM

To perform a systematic review summarising evidence for efficacy of systemic and endoscopic intralesional medical therapy in established small bowel strictures in adult CD patients.

METHODS

A systematic search of MEDLINE, EMBASE, CENTRAL and Scopus was conducted. Primary outcomes were rates of surgical resection and repeat endoscopic dilation. Pooled event rates from random effects models across studies with 95% confidence intervals were reported.

RESULTS

Ten studies describing systemic medical therapy and eight studies of intralesional injection were included. One randomised controlled trial each for systemic therapy and intrastricture injection were identified. Only observational studies were found for systemic biologic therapies, which exclusively included tumour necrosis factor (TNF) antagonists, while intralesional therapies all involved corticosteroids except for one study that evaluated infliximab. Pooled event rates for surgical resection after systemic and intralesional therapy were 28.3% (95% CI: 18.2%-41.3%) and 18.5% (95% CI: 8.3%-36.2%), respectively over a median follow-up of 23 months (range 5.5-105.8), and 21.8 months (range 5-47). Risk of repeat endoscopic balloon dilation in those with intralesional therapy was 58.3% (95% CI: 36.6%-77.3%) over a median follow-up of 21.8 months (range 5-47).

CONCLUSIONS

There are no favoured therapies for patients with stricturing small bowel CD. Data are lacking for ustekinumab and vedolizumab. No endoscopic intralesional medications provided a clear benefit for prevention of repeat EBD or surgery.

Tailored Medical Management of the Complex Postoperative Crohn's Disease Patient

Despite advancements in medical therapy, many patients with Crohn's disease continue to require surgery for intestinal resection and/or management of perianal disease at some point in their disease course. Unfortunately, in this complex group of patients, postoperative disease recurrence rates are high. Medical prophylaxis can be used to prevent Crohn's disease recurrence or manage residual disease after surgery, but the ideal timing to start medications after surgery varies based on patient risk factors and patient preference for medication use. Currently, the largest medical treatment effects are seen with thiopurines and antitumor necrosis factor antibodies, but there are continually expanding options as new medical therapies are developed. A proposed algorithm stratified based on patient risk factors is provided.

Acupuncture in Inflammatory Bowel Disease

Scientific research into the effects and mechanisms of acupuncture for gastrointestinal diseases including inflammatory bowel disease has been rapidly growing in the past several decades. In this review, we discuss the history, theory, and methodology of acupuncture and review potentially beneficial mechanisms of action of acupuncture for managing inflammatory bowel disease. Acupuncture has been shown to decrease disease activity and inflammation via increase of vagal activity in inflammatory bowel disease. Acupuncture has demonstrated beneficial roles in the regulation of gut dysbiosis, intestinal barrier function, visceral hypersensitivity, gut motor dysfunction, depression/anxiety, and pain, all of which are factors that can significantly impact quality of life in patients with inflammatory bowel disease. A number of clinical trials have been performed to investigate the therapeutic effects of acupuncture in ulcerative colitis and Crohn's disease. Although the data from these trials are promising, more studies are needed given the heterogeneous and multifactorial aspects of inflammatory bowel disease. There is also an important need to standardize acupuncture methodology, study designs, and outcome measurements.

Genetic architecture distinguishes systemic juvenile idiopathic arthritis from other forms of juvenile idiopathic arthritis: clinical and therapeutic implications

OBJECTIVES

Juvenile idiopathic arthritis (JIA) is a heterogeneous group of conditions unified by the presence of chronic childhood arthritis without an identifiable cause. Systemic JIA (sJIA) is a rare form of JIA characterised by systemic inflammation. sJIA is distinguished from other forms of JIA by unique clinical features and treatment responses that are similar to autoinflammatory diseases. However, approximately half of children with sJIA develop destructive, long-standing arthritis that appears similar to other forms of JIA. Using genomic approaches, we sought to gain novel insights into the pathophysiology of sJIA and its relationship with other forms of JIA.

METHODS

We performed a genome-wide association study of 770 children with sJIA collected in nine countries by the International Childhood Arthritis Genetics Consortium. Single nucleotide polymorphisms were tested for association with sJIA. Weighted genetic risk scores were used to compare the genetic architecture of sJIA with other JIA subtypes.

RESULTS

The major histocompatibility complex locus and a locus on chromosome 1 each showed association with sJIA exceeding the threshold for genome-wide significance, while 23 other novel loci were suggestive of association with sJIA. Using a combination of genetic and statistical approaches, we found no evidence of shared genetic architecture between sJIA and other common JIA subtypes.

CONCLUSIONS

The lack of shared genetic risk factors between sJIA and other JIA subtypes supports the hypothesis that sJIA is a unique disease process and argues for a different classification framework. Research to improve sJIA therapy should target its unique genetics and specific pathophysiological pathways.

Impact of Low Immunoglobulin G Levels on Disease Outcomes in Patients with Inflammatory Bowel Diseases

BACKGROUND

Inflammatory bowel diseases (IBDs) are considered immune-mediated disorders with dysregulated innate and adaptive immunities. Secondary immunogloblin deficiency can occur in IBD and its impact on the disease course of IBD is not clear.

AIMS

We sought to determine associations between low IgG/G1 levels and poor clinical outcomes in IBD patients.

METHODS

This historic cohort study was performed on IBD patients with obtained IgG/IgG1 levels. The primary outcome was defined as any IBD-related bowel resection surgery and/or hospitalization. Subgroup analyses assessed particular surgical outcomes in Crohn's disease (CD), ulcerative colitis (UC) or indeterminate colitis (IC), and ileal pouch-anal anastomosis (IPAA). The secondary outcomes included IBD drug escalations and C. difficile or cytomegalovirus infections.

RESULTS

A total of 136 IBD patients had IgG/G1 levels checked and adequate follow-up, 58 (42.6 %) with normal IgG/G1 levels and 78 (57.4 %) having low levels. A total of 49 patients (62.8 %) with low immunoglobulin levels had IBD-related surgeries or hospitalizations, compared to 33 patients (56.9 %) with normal levels [odds ratio (OR) 1.28, 95 % confidence interval (CI) 0.64-2.56; p = 0.49]. Low IgG/G1 levels were associated with IBD-related surgery in CD in univariate analysis [hazard ratio (HR) 4.42, 95 % CI 1.02-19.23; p = 0.048] and in Kaplan-Meier survival curve analysis (p = 0.03), with a trend toward significance on multivariate analysis (HR 3.07, 95 % CI 0.67-14.31; p = 0.15). IBD patients with low IgG/G1 levels required more small bowel resections (12.8 vs. 1.7 %, p = 0.024) and 5-aminosalicylate initiations (28.2 vs. 13.8 %, p = 0.045).

CONCLUSIONS

Our study demonstrated a possible association between low IgG/G1 levels and poor outcomes in CD including surgery. Future implications include using immunoglobulin levels in IBD patients as a prognostic indicator or boosting humoral immunity as a treatment in this subset.

A Pleiotropic Missense Variant in SLC39A8 Is Associated With Crohn's Disease and Human Gut Microbiome Composition

BACKGROUND & AIMS

Genome-wide association studies have identified 200 inflammatory bowel disease (IBD) loci, but the genetic architecture of Crohn's disease (CD) and ulcerative colitis remain incompletely defined. Here, we aimed to identify novel associations between IBD and functional genetic variants using the Illumina ExomeChip (San Diego, CA).

METHODS

Genotyping was performed in 10,523 IBD cases and 5726 non-IBD controls. There were 91,713 functional single-nucleotide polymorphism loci in coding regions analyzed. A novel identified association was replicated further in 2 independent cohorts. We further examined the association of the identified single-nucleotide polymorphism with microbiota from 338 mucosal lavage samples in the Mucosal Luminal Interface cohort measured using 16S sequencing.

RESULTS

We identified an association between CD and a missense variant encoding alanine or threonine at position 391 in the zinc transporter solute carrier family 39, member 8 protein (SLC39A8 alanine 391 threonine, rs13107325) and replicated the association with CD in 2 replication cohorts (combined meta-analysis P = 5.55 × 10(-13)). This variant has been associated previously with distinct phenotypes including obesity, lipid levels, blood pressure, and schizophrenia. We subsequently determined that the CD risk allele was associated with altered colonic mucosal microbiome composition in both healthy controls (P = .009) and CD cases (P = .0009). Moreover, microbes depleted in healthy carriers strongly overlap with those reduced in CD patients (P = 9.24 × 10(-16)) and overweight individuals (P = 6.73 × 10(-16)).

CONCLUSIONS

Our results suggest that an SLC39A8-dependent shift in the gut microbiome could explain its pleiotropic effects on multiple complex diseases including CD.

The Significance of Sessile Serrated Polyps in Inflammatory Bowel Disease

BACKGROUND

The significance of serrated lesions in inflammatory bowel disease (IBD) remains unclear. We aim to characterize synchronous and metachronous lesions in IBD patients with an index serrated polyp and compare them to sporadic subjects with SSP.

METHODS

Serrated lesions in patients with IBD were identified from a pathology database and, after review, were reclassified as hyperplastic (HP), sessile serrated (SSPs), or serrated polyps unclassifiable (SPU).

RESULTS

One hundred thirty-four IBD patients were found to have 147 serrated polyps at index colonoscopy. SSPs were more likely to be located in the right colon: SSP (76.0%), SPU (41.7%) and HP (27.8%); P = 0.002. Synchronous multifocal visible dysplasia occurred more frequently in the SSP or SPU groups (44.5% and 66%) compared to the HP group (12%); P = 0.031. Among 13 IBD patients with index SSP followed over a median of 6 years, 61.5% developed metachronous visible dysplasia or additional SSPs. Larger index SSP size was associated with higher risk of developing subsequent visible dysplasia with a 10% increase for every 1 mm increase in size (HR = 1.1; P = 0.028), but was not associated with developing subsequent SSP (P = 0.50). The risk of subsequent SSP or visible dysplasia was no different between the IBD and non-IBD groups, but there was a trend suggesting SSP may be a marker of increased early risk of metachronous visible dysplasia in IBD patients.

CONCLUSIONS

IBD patients with an index SSP and SPU have a heightened risk of synchronous multifocal visible dysplasia. Additionally, IBD patients with SSP may be at risk of early metachronous visible dysplasia.

Hemoglobin and hematocrit levels in the prediction of complicated Crohn's disease behavior--a cohort study

Background

Markers that predict the occurrence of a complicated disease behavior in patients with Crohn's disease (CD) can permit a more aggressive therapeutic regimen for patients at risk. The aim of this cohort study was to test the blood levels of hemoglobin (Hgb) and hematocrit (Hct) for the prediction of complicated CD behavior and CD related surgery in an adult patient population.

Methods

Blood samples of 62 CD patients of the German Inflammatory Bowel Disease-network “Kompetenznetz CED” were tested for the levels of Hgb and Hct prior to the occurrence of complicated disease behavior or CD related surgery. The relation of these markers and clinical events was studied using Kaplan-Meier survival analysis and adjusted COX-proportional hazard regression models.

Results

The median follow-up time was 55.8 months. Of the 62 CD patients without any previous complication or surgery 34% developed a complication and/or underwent CD related surgery. Low Hgb or Hct levels were independent predictors of a shorter time to occurrence of the first complication or CD related surgery. This was true for early as well as late occurring complications. Stable low Hgb or Hct during serial follow-up measurements had a higher frequency of complications compared to patients with a stable normal Hgb or Hct, respectively.

Conclusions

Determination of Hgb or Hct in complication and surgery naïve CD patients might serve as an additional tool for the prediction of complicated disease behavior.

Gene-gene and gene-environment interactions in ulcerative colitis

Genome-wide association studies (GWAS) have identified at least 133 ulcerative colitis (UC) associated loci. The role of genetic factors in clinical practice is not clearly defined. The relevance of genetic variants to disease pathogenesis is still uncertain because of not characterized gene-gene and gene-environment interactions. We examined the predictive value of combining the 133 UC risk loci with genetic interactions in an ongoing inflammatory bowel disease (IBD) GWAS. The Wellcome Trust Case-Control Consortium (WTCCC) IBD GWAS was used as a replication cohort. We applied logic regression (LR), a novel adaptive regression methodology, to search for high-order interactions. Exploratory genotype correlations with UC sub-phenotypes [extent of disease, need of surgery, age of onset, extra-intestinal manifestations and primary sclerosing cholangitis (PSC)] were conducted. The combination of 133 UC loci yielded good UC risk predictability [area under the curve (AUC) of 0.86]. A higher cumulative allele score predicted higher UC risk. Through LR, several lines of evidence for genetic interactions were identified and successfully replicated in the WTCCC cohort. The genetic interactions combined with the gene-smoking interaction significantly improved predictability in the model (AUC, from 0.86 to 0.89, P = 3.26E-05). Explained UC variance increased from 37 to 42 % after adding the interaction terms. A within case analysis found suggested genetic association with PSC. Our study demonstrates that the LR methodology allows the identification and replication of high-order genetic interactions in UC GWAS datasets. UC risk can be predicted by a 133 loci and improved by adding gene-gene and gene-environment interactions.

Dense genotyping of immune-related disease regions identifies nine new risk loci for primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a severe liver disease of unknown etiology leading to fibrotic destruction of the bile ducts and ultimately to the need for liver transplantation. We compared 3,789 PSC cases of European ancestry to 25,079 population controls across 130,422 SNPs genotyped using the Immunochip. We identified 12 genome-wide significant associations outside the human leukocyte antigen (HLA) complex, 9 of which were new, increasing the number of known PSC risk loci to 16. Despite comorbidity with inflammatory bowel disease (IBD) in 72% of the cases, 6 of the 12 loci showed significantly stronger association with PSC than with IBD, suggesting overlapping yet distinct genetic architectures for these two diseases. We incorporated association statistics from 7 diseases clinically occurring with PSC in the analysis and found suggestive evidence for 33 additional pleiotropic PSC risk loci. Together with network analyses, these findings add to the genetic risk map of PSC and expand on the relationship between PSC and other immune-mediated diseases.

PTGER4 expression-modulating polymorphisms in the 5p13.1 region predispose to Crohn's disease and affect NF-κB and XBP1 binding sites

Background

Genome-wide association studies identified a PTGER4 expression-modulating region on chromosome 5p13.1 as Crohn's disease (CD) susceptibility region. The study aim was to test this association in a large cohort of patients with inflammatory bowel disease (IBD) and to elucidate genotypic and phenotypic interactions with other IBD genes.

Methodology/Principal Findings

A total of 7073 patients and controls were genotyped: 844 CD and 471 patients with ulcerative colitis and 1488 controls were analyzed for the single nucleotide polymorphisms (SNPs) rs4495224 and rs7720838 on chromosome 5p13.1. The study included two replication cohorts of North American (CD: n = 684; controls: n = 1440) and of German origin (CD: n = 1098; controls: n = 1048). Genotype-phenotype, epistasis and transcription factor binding analyses were performed. In the discovery cohort, an association of rs4495224 (p = 4.10×10⁻⁵; 0.76 [0.67–0.87]) and of rs7720838 (p = 6.91×10⁻⁴; 0.81 [0.71–0.91]) with susceptibility to CD was demonstrated. These associations were confirmed in both replication cohorts. In silico analysis predicted rs4495224 and rs7720838 as essential parts of binding sites for the transcription factors NF-κB and XBP1 with higher binding scores for carriers of the CD risk alleles, providing an explanation of how these SNPs might contribute to increased PTGER4 expression. There was no association of the PTGER4 SNPs with IBD phenotypes. Epistasis detected between 5p13.1 and ATG16L1 for CD susceptibility in the discovery cohort (p = 5.99×10⁻⁷ for rs7720838 and rs2241880) could not be replicated in both replication cohorts arguing against a major role of this gene-gene interaction in the susceptibility to CD.

Conclusions/Significance

We confirmed 5p13.1 as a major CD susceptibility locus and demonstrate by in silico analysis rs4495224 and rs7720838 as part of binding sites for NF-κB and XBP1. Further functional studies are necessary to confirm the results of our in silico analysis and to analyze if changes in PTGER4 expression modulate CD susceptibility.

Host-microbe interactions have shaped the genetic architecture of inflammatory bowel disease

Crohn’s disease (CD) and ulcerative colitis (UC), the two common forms of inflammatory bowel disease (IBD), affect over 2.5 million people of European ancestry with rising prevalence in other populations¹. Genome-wide association studies (GWAS) and subsequent meta-analyses of CD and UC^2,3 as separate phenotypes implicated previously unsuspected mechanisms, such as autophagy⁴, in pathogenesis and showed that some IBD loci are shared with other inflammatory diseases⁵. Here we expand knowledge of relevant pathways by undertaking a meta-analysis of CD and UC genome-wide association scans, with validation of significant findings in more than 75,000 cases and controls. We identify 71 new associations, for a total of 163 IBD loci that meet genome-wide significance thresholds. Most loci contribute to both phenotypes, and both directional and balancing selection effects are evident. Many IBD loci are also implicated in other immune-mediated disorders, most notably with ankylosing spondylitis and psoriasis. We also observe striking overlap between susceptibility loci for IBD and mycobacterial infection. Gene co-expression network analysis emphasizes this relationship, with pathways shared between host responses to mycobacteria and those predisposing to IBD.

Amino acid position 11 of HLA-DRβ1 is a major determinant of chromosome 6p association with ulcerative colitis

The major histocompatibility complex (MHC) on chromosome 6p is an established risk locus for ulcerative colitis (UC) and Crohn's disease (CD). We aimed to better define MHC association signals in UC and CD by combining data from dense single-nucleotide polymorphism (SNP) genotyping and from imputation of classical human leukocyte antigen (HLA) types, their constituent SNPs and corresponding amino acids in 562 UC, 611 CD and 1428 control subjects. Univariate and multivariate association analyses were performed, controlling for ancestry. In univariate analyses, absence of the rs9269955 C allele was strongly associated with risk for UC (P = 2.67 × 10(-13)). rs9269955 is a SNP in the codon for amino acid position 11 of HLA-DRβ1, located in the P6 pocket of the HLA-DR antigen binding cleft. This amino acid position was also the most significantly UC-associated amino acid in omnibus tests (P = 2.68 × 10(-13)). Multivariate modeling identified rs9269955-C and 13 other variants in best predicting UC vs control status. In contrast, there was only suggestive association evidence between the MHC and CD. Taken together, these data demonstrate that variation at HLA-DRβ1, amino acid 11 in the P6 pocket of the HLA-DR complex antigen binding cleft is a major determinant of chromosome 6p association with UC.

How patients view probiotics: findings from a multicenter study of patients with inflammatory bowel disease and irritable bowel syndrome

BACKGROUND

Patients with inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) have access to a growing number of probiotic products marketed to improve digestive health. It is unclear how patients make decisions about probiotics and what role they expect their gastroenterologists to play as they consider using probiotics. Understanding patients' knowledge, attitudes and expectations of probiotics may help gastroenterologists engage patients in collaborative discussions about probiotics.

STUDY

Focus groups were conducted with patients with IBD and IBS at the Cleveland Clinic, Mayo Clinic, and Johns Hopkins University. Inductive analytic methods were used to identify common themes and draw interpretations from focus group narratives.

RESULTS

One hundred thirty-six patients participated in 22 focus groups between March and August 2009. Patients viewed probiotics as an appealing alternative to pharmaceutical drugs and understood probiotics as a more "natural," low-risk therapeutic option. Many patients were hesitant to use them without consulting their gastroenterologists. Patients would weigh the risks and benefits of probiotics, their disease severity and satisfaction with current treatments when considering probiotic use.

CONCLUSIONS

Patients are interested in probiotics but have many unanswered questions about their use. Our findings suggest that patients with IBD and IBS will look to gastroenterologists and other clinicians as trustworthy advisors regarding the utility of probiotics as an alternative or supplement to pharmaceutical drugs. Gastroenterologists and other clinicians who care for patients with these diseases should be prepared to discuss the potential benefits and risks of probiotics and assist patients in making informed decisions about their use.

Efficacy of 5-aminosalicylates in ulcerative colitis: systematic review and meta-analysis

OBJECTIVES

The efficacy of 5-aminosalicylic acids (5-ASAs) in ulcerative colitis (UC) has been studied previously in meta-analyses. However, several randomized controlled trials (RCTs) have been published recently, and no previous meta-analysis has studied the effect of 5-ASA dosage used.

METHODS

MEDLINE, EMBASE, and the Cochrane central register of controlled trials were searched (through December 2010). Eligible trials recruited adults with active or quiescent UC, comparing different doses of 5-ASAs with themselves or placebo. Dichotomous data were pooled to obtain relative risk (RR) of failure to achieve remission in active UC, and RR of relapse of disease activity in quiescent UC, with a 95% confidence interval (CI). The number needed to treat (NNT) was calculated from the reciprocal of the risk difference.

RESULTS

The search identified 3,061 citations, and 37 RCTs were eligible. Of these, 11 compared 5-ASA with placebo in active UC remission, with the RR of no remission with 5-ASAs of 0.79 (95% CI 0.73-0.85; NNT=6). Doses of ≥ 2.0 g/day were more effective than <2.0 g/day for remission (RR=0.91; 95% CI 0.85-0.98). There were 11 RCTs comparing 5-ASAs with placebo in preventing relapse of quiescent UC, with the RR of relapse of 0.65 (95% CI 0.55-0.76; NNT=4). Doses of ≥ 2.0 g/day appeared more effective than <2.0 g/day for preventing relapse (RR=0.79; 95% CI 0.64-0.97).

CONCLUSIONS

5-ASAs are highly effective for inducing remission and preventing relapse in UC. Evidence suggests that doses of ≥ 2.0 g/day have greater efficacy, although doses >2.5 g/day do not appear to lead to higher remission rates.

Pathogenesis of postoperative recurrence in Crohn's disease

The majority of patients with Crohn's disease (CD) require surgery during the course of their disease, but such surgery is typically not curative. Although some studies suggest that the disease state is theoretically reset to its earliest phase following surgery, disease phenotype and natural history of CD do not change significantly after surgery, leading to high rates of recurrence. Factors predisposing to this recurrence are not well defined, so there is a need for and a unique opportunity to develop a better understanding of the pathogenesis of recurrent inflammation and associated risk factors after an ileocolic resection. This paper reviews the postoperative disease outcome and evolution based on defining the combination of the patient's microbial flora, environmental exposure history, immune response and genetic make-up.

ATG16L1 and NOD2 interact in an autophagy-dependent antibacterial pathway implicated in Crohn's disease pathogenesis

BACKGROUND & AIMS

The identification of numerous genes that confer susceptibility to Crohn's disease (CD) indicates that this complex disease might arise from alterations in several genes with related functions. We examined the functional interaction between the CD risk genes ATG16L1 and NOD2 to identify an autophagy-dependent pathway that is altered by disease-associated variants.

METHODS

We assessed Nod2 signaling and autophagy activation in response to muramyl dipeptide (MDP) by immunoblot, confocal microscopy, flow cytometry, reporter gene, and gentamicin protection assays in human epithelial cell lines and primary human macrophages and dendritic cells from healthy individuals. The requirement of Nod2 and ATG16L1 expression and the effects of CD-associated variants in MDP-stimulated autophagy and Nod2-dependent signaling were assessed in cell lines manipulated by RNA interference, inhibitors, or ATG16L1 or NOD2 variants and in primary macrophages and dendritic cells from healthy genotyped donors.

RESULTS

MDP stimulation of epithelial cells, macrophages, and dendritic cells activated autophagy and nuclear factor κB and mitogen-activated protein kinase signaling; it also increased killing of Salmonella. These responses depended on ATG16L1 and Nod2 expression and were impaired by CD-associated NOD2 variants. Nod2-dependent signaling was not impaired in cells with the ATG16L1 T300A genotype, which is associated with CD. However, the ATG16L1 T300A variant blocked the increase in MDP-mediated killing of Salmonella only in epithelial cell lines and not primary macrophages or dendritic cells.

CONCLUSIONS

ATG16L1 and NOD2 are components of an autophagy-mediated antibacterial pathway that is altered in a cell- and function-specific manner by CD-associated mutations.

Gene-gene interactions in inflammatory bowel disease: biological and clinical implications

The results of recently completed genome-wide association studies have advanced knowledge of inflammatory bowel disease (IBD) genetics, including the identification of over 30 genes or loci associated with Crohn's disease (CD). The possibility of interactions between genes, referred to by the term epistasis, needs to be carefully considered as both genetic and functional studies in IBD move forward. We review a paper in this issue of the Journal that reports evidence of epistasis in CD, and we discuss important issues that arise when trying to determine whether there is indeed interaction between genes and what their potential implications for disease pathogenesis and clinical outcome might be.

Genetic variants in the region harbouring IL2/IL21 associated with ulcerative colitis

OBJECTIVES

Genetic susceptibility is known to play a large part in the predisposition to the inflammatory bowel diseases (IBDs) known as Crohn's disease (CD) and ulcerative colitis (UC). The IL2/IL21 locus on 4q27 is known to be a common risk locus for inflammatory disease (shown in coeliac disease, type 1 diabetes, rheumatoid arthritis, systemic lupus erythematosus and psoriasis), while the roles that interleukin 2 (IL2) and IL21 play in the immune response also make them attractive candidates for IBD. The objective of this study was to test for association between the IL2/IL21 locus and the IBDs.

METHODS

The four single nucleotide polymorphisms (SNPs) in the IL2/IL21 locus most associated with coeliac disease were genotyped in 1590 subjects with IBD and 929 controls from The Netherlands, and then replicated in a North American cohort (2387 cases and 1266 controls) and an Italian cohort (805 cases and 421 controls), yielding a total of 4782 cases (3194 UC, 1588 CD) and 2616 controls. Allelic association testing and a pooled analysis using a Cochran-Mantel-Haenszel test were performed.

RESULTS

All four SNPs were strongly associated with UC in all three cohorts and reached genome-wide significance in the pooled analysis (rs13151961 p = 1.35 x 10(-10), rs13119723 p = 8.60 x 10(-8), rs6840978 p = 3.0 7x 10(-8), rs6822844 p = 2.77 x 10(-9)). A moderate association with CD was also found in the pooled analysis (p value range 0.0016-9.86 x 10(-5)).

CONCLUSIONS

A strong association for the IL2/IL21 locus with UC was found, which also confirms it as a general susceptibility locus for inflammatory disease.

Helping patients make informed choices about probiotics: a need for research

Applications of probiotics in the treatment of gastrointestinal disorders are gaining acceptance among patients, despite evidence that probiotics can present substantial health risks, particularly for patients who are immunocompromised or seriously ill. Patients will likely formulate their attitudes and beliefs about probiotic therapies with reference to interpretive frameworks that compare probiotics with more familiar therapeutic modalities, including complementary and alternative medicines, pharmacological therapies, and gene-transfer technologies. Each of these frameworks highlights a different set of benefit-to-risk considerations regarding probiotic usage and reinforces extreme characterizations of both the therapeutic promise and peril of probiotics. Considerable effort may be required to help patients make informed choices about probiotic therapies.

Using technology to promote gastrointestinal outcomes research: a case for electronic health records

Electronic health records (EHRs) have been shown to reduce medication errors, improve patient outcomes, and create administrative efficiencies. Numerous public and private efforts are currently underway to achieve universal EHR adoption in the United States by the year 2014. EHRs hold a great potential to integrate clinical care and research by allowing input of clinical data in a structured format, facilitating electronic data capture for clinical trials and providing linkage with genomic information. The goal of this article is to inform the academic gastrointestinal community about the research opportunities created by the widespread adoption of EHRs and present a systematic approach in utilizing EHR-derived data for observational, experimental, or translational studies.

IL23R and ATG16L1 SNPs in IBD: alphabet soup or something more?

The results of recently completed genome-wide association studies have rapidly advanced knowledge of inflammatory bowel disease (IBD) genetics. Several promising associations between IBD and gene variants have been identified with the two best replicated so far being variants in the IL23R and ATG16L1 genes. These findings highlight the importance of the immune system and interactions with intestinal microflora in the pathogenesis of IBD.

Ulcerative colitis: responding to the challenges

Aminosalicylates are the first-line therapy for patients with mild to moderate active ulcerative colitis. Treatment should start at dosages of 4.8 g per day of the active 5-aminosalicylate moiety, rather than starting at a lower dosage and increasing if treatment fails. Infliximab has been shown to be effective and is now approved by the US Food and Drug Administration for the treatment of moderately to severely active ulcerative colitis in patients who have had an inadequate response to conventional therapy.

Assessment of reliability and validity of IBD phenotyping within the National Institutes of Diabetes and Digestive and Kidney Diseases (NIDDK) IBD Genetics Consortium (IBDGC)

BACKGROUND

The NIDDK IBD Genetics Consortium (IBDGC) collects DNA and phenotypic data from inflammatory bowel disease (IBD) subjects to provide a resource for genetic studies. No previous studies have been performed on the reliability and validity of phenotypic determinations in either Crohn's disease (CD) or ulcerative colitis (UC) using primary records. Our aim was to determine the reliability and validity of these phenotypic assessments.

METHODS

The de-identified records of 30 IBD patients were reviewed by 2 phenotypers per center using a standard protocol for phenotypic assessment. Each phenotyper evaluated 10 charts on 2 occasions 5 months apart. Reliability was expressed as the kappa (kappa) statistic. Performance characteristics were determined by comparison to a consensus-derived "gold standard" and by generation of receiver operating characteristic (ROC) curves.

RESULTS

Agreement for diagnosis was excellent (kappa = 0.82; 95% confidence interval [CI]: 0.71-0.92). Agreement for CD location was good for jejunal, ileal, colorectal, and perianal disease with kappa between 0.60 and 0.74 but was fair for esophagogastroduodenal (kappa = 0.36). Agreement for UC extent (kappa = 0.67; 95% CI: 0.48-0.85), and CD behavior (kappa = 0.67; 95% CI: 0.49-0.83) were very good. Area under the ROC curves was greater than 0.84 for diagnosis, CD behavior, UC extent, and ileal and colonic CD location.

CONCLUSIONS

IBD phenotype classification using a standard protocol exhibited very good to excellent inter- and intrarater agreement and validity. This study highlights the importance of standard protocols in generating reliable and valid phenotypic assessments. The data will facilitate estimates of phenotyping misclassification rates that should be considered when making inferences from IBD genotype-phenotype studies.

Phenotype-stratified genetic linkage study demonstrates that IBD2 is an extensive ulcerative colitis locus

OBJECTIVES

The complete elucidation of genetic variants that contribute to inflammatory bowel disease (IBD) will likely include variants that increase risk to both Crohn's disease and ulcerative colitis as well as variants that increase risk for particular phenotypic subsets. The purpose of this study was to assess phenotypic subsets that contribute to the major IBD susceptibility loci.

METHODS

This linkage study encompassed 904 affected relative pairs, representing the largest combined phenotyped cohort to date, and allowing for meaningful subset analyses. Genetic linkage data were stratified by disease location and age at diagnosis.

RESULTS

We establish that some loci, notably the IBD3 and chromosome 3q linkage regions demonstrate contributions from both small intestine and colon cohorts, whereas others, notably the IBD1 (NOD2/CARD15) and IBD2 regions increase risk for small intestine or colon inflammation, respectively. The strongest linkage evidence in this study was for the subset of extensive ulcerative colitis in the region of IBD2 (lod 3.27; p < 0.001). Evidence for linkage in the region of NOD2/CARD15 (IBD1) was stronger for the subset of Crohn's patients with ileal disease (lod 2.56; p= 0.035) compared to the overall Crohn's group, consistent with previous findings that NOD2/CARD15 variants are associated with ileal disease.

CONCLUSIONS

Analyses incorporating disease location in IBD increase the power and enhance the accuracy of genomic localization. Our data provide strong evidence that extensive ulcerative colitis represents a pathophysiologic subset of IBD.

Risk factors for diseases of ileal pouch-anal anastomosis after restorative proctocolectomy for ulcerative colitis

BACKGROUND & AIMS

Although pouchitis is considered the most common adverse sequela of ileal pouch-anal anastomosis (IPAA), inflammatory and noninflammatory conditions other than pouchitis are increasingly being recognized. The risk factors for these non-pouchitis conditions, including Crohn's disease (CD) of the pouch, cuffitis, and irritable pouch syndrome (IPS), have not been studied. The aim of this study was to assess risk factors for inflammatory and noninflammatory diseases of IPAA in a tertiary care setting.

METHODS

The study consisted of 240 consecutive patients who were classified as having healthy pouches (N = 49), pouchitis (N = 61), CD of the pouch (N = 39), cuffitis (N = 41), or IPS (N =50). Demographic and clinical features were assessed to determine risk factors for each of these conditions by using logistic regression analysis.

RESULTS

Risk factors remaining in the final logistic regression models were for pouchitis: IPAA indication for dysplasia (odds ratio [OR], 3.89; 95% confidence interval [CI], 1.69-8.98), never having smoked (OR, 5.09; 95% CI, 1.01-25.69), no use of anti-anxiety agents (OR, 5.19; 95% CI, 1.45-18.59), or use of NSAIDs (OR, 3.24; 95% CI, 1.71-6.13); for CD of the pouch: a long duration of IPAA (OR, 1.20; 95% CI, 1.12-1.30) and current smoking (OR, 4.77; 95% CI, 1.39-16.25); for cuffitis: arthralgias (OR, 4.13; 95% CI, 1.91-8.94) and younger age (OR, 1.16; 95% CI, 1.01-1.33); and for IPS: use of antidepressants (OR, 4.17, 95% CI, 1.95-8.92) or anti-anxiety agents (OR, 3.21; 95% CI, 1.34-7.47).

CONCLUSIONS

The majority of risk factors for the 4 inflammatory and noninflammatory conditions of IPAA are different, suggesting that each of these diseases has a different etiology and pathogenesis. The identification and modification of these risk factors might help patients and clinicians to make a preoperative decision for IPAA, reduce IPAA-related morbidity, and improve response to treatment.

Management of peristomal pyoderma gangrenosum

PURPOSE

This study was designed to evaluate the presentation, management, and outcome of peristomal pyoderma gangrenosum at a specialist colorectal unit and develop a strategy for therapy.

METHODS

Patients with peristomal pyoderma gangrenosum were identified from a prospectively accrued Institutional Review Board-approved stoma database. Data were collected regarding demographics, disease status, history of illness, time to healing, and treatments used from the database and by chart review.

RESULTS

Sixteen patients presented between 1997 and 2002 with peristomal ulceration consistent with a diagnosis of peristomal pyoderma gangrenosum. Diagnosis was predominantly clinically based on a classic presentation of painful, undermined peristomal ulceration. The underlying diagnosis was Crohn's disease in 11 patients, ulcerative colitis in 3, indeterminate colitis in 1, and posterior urethral valves in 1. At the time of development of peristomal pyoderma gangrenosum, the underlying disease was active in 69 percent of patients. Stoma care, ulcer debridement with unroofing of undermined edges, and intralesional corticosteroid injection was associated with a 40 percent complete response rate and further 40 percent partial response rate. Of five patients who received infliximab, four (80 percent) responded to therapy. Complete response after all forms of therapy, including stoma relocation in seven patients, was 87 percent.

CONCLUSIONS

Local wound management and enterostomal therapy are extremely important for patients with peristomal pyoderma gangrenosum. Infliximab may provide a useful option for those failing other forms of medical therapy. Relocation of the stoma is reserved for persistent ulceration failing other therapies, because peristomal pyoderma gangrenosum may recur at the new stoma site.

Differentiating risk factors for acute and chronic pouchitis

BACKGROUND & AIMS

Pouchitis is the most common complication of ileal pouch anal anastomosis in patients with ulcerative colitis. In some cases the inflammation becomes chronic and requires long-term medical therapy. The clinical course and medical therapy are different between acute pouchitis and chronic pouchitis. The aim of this study was to determine if there are predictors of risk for acute vs. chronic pouchitis.

METHODS

Patients with acute pouchitis (N = 40) and patients with chronic pouchitis (N = 40) were matched with a control group who never had pouchitis (N = 40). Data were collected for multiple pre-, peri-, and postoperative factors and follow-up telephone calls were performed. Case-control univariable analyses and multivariate logistic regression were used to measure the association between covariates and pouchitis.

RESULTS

Multivariate logistic regression showed that extensive colonic disease (odds ratio [OR], 2.99; P = .045 for acute pouchitis; and OR, 4.61; P = .010 for chronic pouchitis) and extraintestinal manifestations (OR, 2.88; P = .037 for acute pouchitis; and OR, 2.69; P = .047 for chronic pouchitis) were associated with both acute and chronic pouchitis. Postoperative nonsteroidal anti-inflammatory drug (NSAID) use was associated with chronic pouchitis, but less so with acute pouchitis. Patients with fulminant colitis as an indication for surgery had a decreased risk for developing chronic pouchitis (OR, 0.22; P = .036), but no such association was seen for acute pouchitis.

CONCLUSIONS

Extensive colonic disease and preoperative extraintestinal manifestations are associated with increased risk for both acute and chronic pouchitis. Fulminant colitis leading to colectomy is protective from development of chronic pouchitis. Postoperative use of NSAIDS is a risk factor for chronic pouchitis and possibly for acute pouchitis, and thus should be discouraged for patients who undergo ileal pouch anal anastomosis.

Comprehensive evaluation of inflammatory and noninflammatory sequelae of ileal pouch-anal anastomoses

BACKGROUND AND AIMS

Ileal pouch-anal anastomosis (IPAA) improves quality of life (QOL) for ulcerative colitis patients who require surgery. Crohn's disease (CD) of the pouch, pouchitis, cuffitis, and irritable pouch syndrome (IPS) have an adverse impact on physical and psychological well-being, which can compromise the gain in QOL after the surgery. Their clinical, endoscopic, and histologic features have not been fully characterized. The aim of this study was to compare demographic, clinical, endoscopic, and histologic features between CD of the pouch, pouchitis, cuffitis, IPS, and normal pouches. METHODS We enrolled 124 patients: normal pouches (N = 26), CD of the pouch (N = 23), pouchitis (N = 22), cuffitis (N = 21), and IPS (N = 32). Symptomatology, endoscopy, histology, and the Cleveland Global QOL and the Irritable Bowel Syndrome-QOL scores were compared among the groups.

RESULTS

Univariate analysis of demographic and clinical data showed a possible association between NSAID use and pouchitis, extraintestinal manifestation and cuffitis, and antidepressant use and IPS. There were no differences in the Pouchitis Disease Activity Index symptom scores between the disease groups, with an exception of bleeding, which occurred almost exclusively in cuffitis. Endoscopy was useful in discriminating between CD of the pouch, pouchitis, cuffitis, and normal pouches or IPS. Patients with diseased IPAA had worse QOL scores.

CONCLUSIONS

Symptoms largely overlapped among the disease groups of IPAA. Endoscopy is valuable for diagnosis. Inflammatory or noninflammatory sequelae of IPAA adversely affected patients' QOL.

Endoscopic balloon dilation of ileal pouch strictures

BACKGROUND

Restorative proctocolectomy with ileal pouch-anal anastomosis is the surgical treatment of choice in patients with ulcerative colitis. Strictures can occur at the inlet and outlet of the pouch. Endoscopic balloon dilation has been successfully used in patients with Crohn's strictures at the small intestine and colon. There are no published trials on endoscopic balloon therapy of ileal pouch strictures.

AIM

To evaluate outpatient endoscopic balloon dilation of strictures in ileal pouches.

METHODS

Patients underwent nonfluoroscopy-guided, nonsedated, outpatient endoscopic dilations with an 8.6-mm upper endoscope and through-the-scope balloons (size: 11-18 mm). Pre- and posttreatment Pouchitis Disease Activity Index symptom scores (range: 0-6), endoscopic stricture scores based on resistance in passing the endoscope (range: 0-4), and Cleveland Global Quality of Life were compared.

RESULTS

Nineteen patients with pouch strictures who had concurrent Crohn's disease of the pouch (n = 11), cuffitis (n = 5), and pouchitis (n = 3), including 14 inlet and 14 outlet strictures, were enrolled. The mean number of strictures for each patient was 1.61 +/- 0.78. All strictures were successfully dilated with the through-the-scope balloon, with a mean of 1.74 +/- 1.19 (range: 1-5) sessions for each patient. Nine patients had a second endoscopy at 8 wk and five patients had a third pouch endoscopy at 16 wk after the initial endoscopic dilation. Endoscopic stricture scores immediately (0.30 +/- 0.47), 8 wk (0.40 +/- 0.51), and 16 wk (0.44 +/- 0.76) after the dilation were significantly improved compared to the predilation stricture scores (2.67 +/- 0.78). The symptom scores and quality-of-life (QOL) scores improved at week 8 and 16 following dilation, with a mean follow-up of 6.10 +/- 5.83 months (2-25 months). No complications were experienced with the procedure. One patient with CD who failed endoscopic and medical therapy underwent pouch resection.

CONCLUSION

In conjunction with medical therapy, outpatient endoscopic balloon dilation appears safe and effective in treating pouch inlet and outlet strictures, by relieving symptoms, restoring pouch patency, and improving QOL in the majority of patients.

Azathioprine formulation optimizes metabolite profile in inflammatory bowel disease

BACKGROUND

Recent studies have suggested that mercaptopurine metabolism is influenced by drug formulation (mercaptopurine vs. azathioprine) and concomitant use of 5-aminosalicylic acid medications.

AIM

To determine the influence of dose, formulation and 5-aminosalicylic acid use on mercaptopurine metabolism.

METHODS

Metabolites from 131 inflammatory bowel disease patients were analysed. Logistic regression was used to analyse correlations between dose and metabolite levels. Multivariate analysis was used to determine the effects of drug formulation and 5-aminosalicylic acid use.

RESULTS

A positive correlation was detected between dose and 6-tioguanine nucleotides levels for azathioprine/Imuran formulation (P = 0.005) but not for mercaptopurine formulation. Adjusted mean 6-tioguanine nucleotides levels were similar for both formulations. Adjusted mean 6-methylmercaptopurine levels were higher for mercaptopurine formulation than for azathioprine formulation (1950 vs. 1056, P = 0.04). 5-Aminosalicylic acid use: 6-tioguanine nucleotides levels did not differ based on concomitant 5-aminosalicylic acid use. However, 5-aminosalicylic acid use did result in higher adjusted mean 6-methylmercaptopurine levels: 2078 on 5-aminosalicylic acid vs. 991 off 5-aminosalicylic acid (P = 0.004).

CONCLUSIONS

(i) Azathioprine may have metabolic benefits by achieving a correlation of dose with 6-tioguanine nucleotides levels and by leading to lower mean 6-methylmercaptopurine levels. (ii) 5-aminosalicylic acid use does not significantly impact 6-tioguanine levels and may lead to higher 6-methylmercaptopurine levels.