Validation of the ACE [Albumin, CRP, and Endoscopy] Index in Acute Colitis: Analysis of the CONSTRUCT dataset.

BACKGROUND AND AIMS: In 2020 we reported the ACE Index in acute colitis which used biochemical and endoscopic parameters to predict steroid non-response on admission in patients with acute ulcerative colitis [UC]. We aimed to validate the ACE Index in an independent cohort. METHODS: The validation cohort comprised patients screened as eligible for inclusion in the CONSTRUCT study, a prospective, randomized, placebo-controlled trial which compared the effectiveness of treatment with infliximab vs ciclosporin in patients admitted with acute UC. The CONSTRUCT cohort database was reviewed at The Edinburgh IBD Unit and the same biochemical and endoscopic variables and cut-off values as those in the derivation cohort were applied to the validation cohort. RESULTS: In total, 800 patients were identified; 62.5% [55/88] of patients with a maximum ACE Index of 3 did not respond to intravenous [IV] steroids (positive predictive value [PPV] 62.5%, negative predictive value [NPV] 79.8%). Furthermore, 79.8% [158/198] of patients with an ACE Index of 0 responded to IV steroids [PPV 79.8%, NPV 62.5%]. Receiver operator characteristic [ROC] curve analysis produced an area under the curve [AUC] of 0.663 [p < 0.001]. CONCLUSIONS: We have now reported and externally validated the ACE Index in acute colitis in a combined cohort of over 1000 patients from across the UK. The ACE Index may be used in conjunction with clinical judgement to help identify patients admitted with active UC who are at high risk of not responding to IV steroids. Further studies are required to improve objectivity and accuracy of assessment.

Real-World Cohort Study on the Effectiveness and Safety of Filgotinib Use in Ulcerative Colitis.

BACKGROUND: Filgotinib is a small molecule with preferential inhibition of Janus kinase type 1, approved for the treatment of ulcerative colitis in Scotland in May 2022. We present the first real world experience on its use in clinical practice. METHODS: In this retrospective, observational, cohort study we assessed patients with active ulcerative colitis who received filgotinib in NHS Lothian, Scotland. Baseline demographic, phenotype and follow-up data were collected via review of electronic medical records. RESULTS: We included 91 patients with median treatment duration of 39 weeks (IQR 23-49). Among the cohort, 67% (61/91) were biologic and small molecule naïve, whilst 20.9% (19/91) had failed one and 12.1% (11/91) ≥2 classes of advanced therapy. Of the biologic and small molecule naïve patients, 18% (11/61) were also thiopurine naïve. Clinical remission (partial Mayo score <2) was achieved in 71.9% (41/57) and 76.4% (42/55) of patients at weeks 12 and 24 respectively. Biochemical remission (CRP≤5mg/L) was achieved in 87.3% (62/71) at week 12 and 88.9% (40/45) at week 24. Faecal biomarker (calprotectin <250µg/g) remission was achieved in 82.8% (48/58) at week 12 and 79.5% (35/44) at week 24.At the end of follow-up, median 42 weeks (IQR 27-50), 82.4% (75/91) of patients remained on filgotinib. Severe adverse events leading to drug discontinuation occurred in 2.2% (2/91) and there were 8.8% (8/91) moderate adverse events that required temporary discontinuation. CONCLUSION: These are the first reported data on the real-world efficacy and safety of filgotinib in ulcerative colitis. Our findings demonstrate that filgotinib is an effective and low risk treatment option for these patients.

Establishing key performance indicators for inflammatory bowel disease in the UK.

Background and aims: Healthcare quality improvement (QI) is the systematic process to continuously improve the quality of care and outcomes for patients. The landmark Inflammatory Bowel Disease (IBD) UK National Audits provided a means to measure the variation in care, highlighting the need to define the standards of excellence in IBD care. Through a consensus approach, we aimed to establish key performance indicators (KPIs), providing reliable benchmarks for IBD care delivery in UK. Methods: KPIs that measure critical aspects of a patient journey within an IBD service were identified though stakeholder meetings. A two-stage Delphi consensus was then conducted. The first involved a multidisciplinary team of IBD clinicians and patients to refine definitions and methodology. The second stage assessed feasibility and utility of the proposed QI process by surveying gastroenterology services across UK. Results: First, the four proposed KPIs were refined and included time from primary care referral to diagnosis in secondary care, time to treatment recommendation following a diagnosis, appropriate use of steroids and advanced therapies prescreening and assessment. Second, the Delphi consensus reported >85% agreement on the feasibility of local adoption of the QI process and >75% agreement on the utility of benchmarking of the KPIs. Conclusions: Through a structured approach, we propose quantifiable KPIs for benchmarking to improve and reduce the individual variation in IBD care across the UK.

Multiple infliximab biosimilar switches appear to be safe and effective in a real-world inflammatory bowel disease cohort.

BACKGROUND: Switching from originator infliximab (IFX) to biosimilar IFX is effective and safe. However, data on multiple switching are scarce. The Edinburgh inflammatory bowel disease (IBD) unit has undertaken three switch programmes: (1) Remicade to CT-P13 (2016), (2) CT-P13 to SB2 (2020), and (3) SB2 to CT-P13 (2021). OBJECTIVE: The primary endpoint of this study was to assess CT-P13 persistence following switch from SB2. Secondary endpoints included persistence stratified by the number of biosimilar switches (single, double and triple), effectiveness and safety. METHODS: We performed a prospective, observational, cohort study. All adult IBD patients on IFX biosimilar SB2 underwent an elective switch to CT-P13. Patients were reviewed in a virtual biologic clinic with protocol driven collection of clinical disease activity, C-reactive protein (CRP), faecal calprotectin (FC), IFX trough/antibody levels, and drug survival. RESULTS: 297 patients (CD n = 196 [66%], ulcerative colitis/inflammatory bowel disease unclassified n = 101, [34%]) were switched (followed-up: 7.5 months [6.8-8.1]). This was the third, second and first IFX switch for 67/297 (22.5%), 138/297 (46.5%) and 92/297 (31%) of the cohort respectively. 90.6% of patients remained on IFX during follow-up. The number of switches was not independently associated with IFX persistence after adjusting for confounders. Clinical (p = 0.77), biochemical (CRP ≤5 mg/ml; p = 0.75) and faecal biomarker (FC<250 µg/g; p = 0.63) remission were comparable at baseline, week 12 and week 24. CONCLUSION: Multiple successive switches from IFX originator to biosimilars are effective and safe in patients with IBD, irrespective of the number of IFX switches.

Rates, predictive factors and effectiveness of ustekinumab intensification to 4- or 6-weekly intervals in Crohn's disease.

BACKGROUND: The UNITI trial reports efficacy of ustekinumab (UST) dose intensification in Crohn's disease (CD) from 12- to 8-weekly, but not 4-weekly. We aimed 1) to assess the cumulative incidence of UST dose intensification to 4- or 6-weekly, 2) to identify factors associated with dose intensification, and 3) to assess the effectiveness of this strategy. METHODS: We performed a retrospective, observational cohort study in NHS Lothian including all UST treated CD patients (2015-2020). RESULTS: 163 CD patients were treated with UST (median follow-up: 20.3 months [13.4-38.4]), of whom 55 (33.7%) underwent dose intensification to 4-weekly (n = 50, 30.7%) or 6-weekly (n = 5, 3.1%). After 1 year 29.9% were dose intensified. Prior exposure to both anti-TNF and vedolizumab (HR 9.5; 1.3-70.9), and concomitant steroid use at UST start (HR 1.8; 1.0-3.1) were associated with dose intensification. Following dose intensification, 62.6% patients (29/55) remained on UST beyond 1 year. Corticosteroid-free clinical remission was achieved in 27% at week 16 and 29.6% at last follow-up. CONCLUSION: One third of CD patients treated with UST underwent dose intensification to a 4- or 6-weekly interval within the first year. Patients who failed both anti-TNF and vedolizumab, or required steroids at initiation were more likely to dose intensify.

The Value of a Dedicated IBD Flare Clinic to Effectively Manage Exacerbations of Inflammatory Bowel Disease: The Edinburgh IBD Unit.

We assessed the impact of a dedicated inflammatory bowel disease flare clinic. Attenders had more changes to maintenance medications made and less steroid use than inflammatory bowel disease patients reviewed at the Acute Receiving Unit. This model of care may potentially reduce hospital admissions.

Incidence of collagenous colitis in NHS Lothian: a population-based study.

Objective: Increases in incidence of collagenous colitis (CC) have been documented across Europe; however, previous data from NHS Lothian (1998-2003) demonstrated this to be a low-prevalence area. We aimed to assess incidence of CC in NHS Lothian over time by comparing a more recent cohort (2013-2018) with our existing cohort. Methods: All histologically confirmed diagnoses of CC between 2013 and 2018 were obtained from the NHS Lothian colorectal pathology department (Western General Hospital, Edinburgh). Case record review was performed to obtain relevant demographic and clinical data. Data were also collected regarding the availability of colonoscopy in NHS Lothian. Results: 224 cases of CC were diagnosed between 2013 and 2018, compared with 25 between 1998 and 2003. Mean annual incidence rose from 0.5/100 000 population to 4.3/100 000 population. Incidence in females ≥60 years old rose from 2.3/100 000 population to 22.4/100 000 population (p<0.001). The total number of colonoscopies performed increased by 179.1% from 15 262 (1998-2003) to 42 600 (2013-2018), with the number of CC cases per 1000 colonoscopies performed rising from 1.7 to 5.3 (p<0.001). Conclusion: We describe the increasing incidence of CC in Southeast Scotland, with temporal trends comparable to other European countries. The increase is particularly marked in older females and parallels increasing numbers of colonoscopies being performed.

Patterns of emergency admission for IBD patients over the last 10 years in Lothian, Scotland: a retrospective prevalent cohort analysis.

OBJECTIVE: It is unclear how the compounding prevalence of inflammatory bowel disease (IBD) has translated into the causes and rates of hospitalisation, particularly in an era of increased biologic prescribing. We aimed to analyse these trends in a population-based IBD cohort over the last 10 years. DESIGN: The Lothian IBD registry is a complete, validated, prevalent database of IBD patients in NHS Lothian, Scotland. ICD-10 coding of hospital discharge letters from all IBD patient admissions to secondary care between 1 January 2010 and 31 December 2019 was interrogated for admission cause, with linkage to local/national data sets on death and prescribed drugs. RESULTS: Fifty-seven per cent (4673/8211) of all IBD patients were admitted to secondary care for >24 h between 1 January 2010 and 31 December 2019. In patients <40 years, IBD was the commonest reason for admission (38% of admissions), whereas infection was the most common cause in those >60 years (19% of admissions). Three per cent (243/8211) of IBD patients accounted for 50% of the total IBD bed-days over the study period. Age-standardised IBD admission rates fell from 39.4 to 25.5 admissions per 100,000 population between 2010 and 2019, an average annual percentage reduction of 3% (95% CI -4.5% to -2.1%, p < 0.0001). Non-IBD admission rates were unchanged overall (145-137 per 100,000 population) and specifically for serious (hospitalisation) and severe (ITU admission or death) infection over the same period. CONCLUSION: Despite compounding prevalence and increased biologic use, IBD admission rates are falling. The cause of admission varies with age, with infection the predominant cause in older patients.

Effectiveness and Safety of Adalimumab Biosimilar SB5 in Inflammatory Bowel Disease: Outcomes in Originator to SB5 Switch, Double Biosimilar Switch and Bio-Naïve SB5 Observational Cohorts.

BACKGROUND AND AIMS: Multiple adalimumab [ADA] biosimilars are now approved for use in inflammatory bowel disease [IBD]; however, effectiveness and safety data remain scarce. We aimed to investigate long-term outcomes of the ADA biosimilar SB5 in IBD patients following a switch from the ADA originator [SB5-switch cohort] or after start of SB5 [SB5-start cohort]. METHODS: We performed an observational cohort study in a tertiary IBD referral centre. All IBD patients treated with Humira underwent an elective switch to SB5. We identified all these patients in a biological prescription database that prospectively registered all ADA start and stop dates including brand names. Data on IBD phenotype, C-reactive protein [CRP], drug persistence, ADA drug and antibody levels, and faecal calprotectin were collected. RESULTS: In total, 481 patients were treated with SB5, 256 in the SB5-switch cohort (median follow-up: 13.7 months [IQR 8.6-15.2]) and 225 in the SB5-start cohort [median follow-up: 8.3 months [4.2-12.8]). Of the SB5-switch cohort, 70.8% remained on SB5 beyond 1 year; 90/256 discontinued SB5, mainly due to adverse events [46/90] or secondary loss of response [37/90]. In the SB5-start cohort, 81/225 discontinued SB5, resulting in SB5-drug persistence of 60.3% beyond 1 year. No differences in clinical remission [p = 0.53], CRP [p = 0.80], faecal calprotectin [p = 0.40] and ADA trough levels [p = 0.55] were found between baseline, week 26 and week 52 following switch. Injection site pain was the most frequently reported adverse event. CONCLUSION: Switching from ADA originator to SB5 appeared effective and safe in this study with over 12 months of follow-up.

Prognostic factors associated with unhealed perineal wounds post-proctectomy for perianal Crohn's disease: a two-centre study.

AIM: The aim of this work was to determine the factors associated with poor wound healing in patients with perianal Crohn's disease (pCD) who had undergone proctectomy in the era of biologic therapies. METHOD: Case record review was performed on 103 patients with pCD who underwent proctectomy at St Mark's Hospital, Harrow and the Western General Hospital, Edinburgh between 2005 and 2017. Healing rates at 6 and 12 months post-proctectomy were considered; univariate analysis was performed. RESULTS: Sixty out of 103 patients (58.3%) had failure of wound healing at 6 months and 41/103 (39.8%) at 12 months. In total, 63.1% (65/103) patients received biologic therapies prior to proctectomy; however, exposure to biologics was not a significant factor in predicting failure of wound healing at 12 months (infliximab p = 0.255; adalimumab p = 0.889; vedolizumab p = 0.153). Male gender was the only variable associated with poor wound healing at 12 months on univariate analysis (p = 0.017). A lower pre-operative C-reactive protein was associated with early wound healing at 6 months compared with at 12 months (p = 0.041) on univariate analysis. Other parameters not associated with rates of wound healing included smoking status, corticosteroid exposure, thiopurine exposure, number of previous biologics, perianal sepsis on MRI within the last 12 months, duration of CD prior to proctectomy and pre-operative albumin. CONCLUSION: More than a third of patients had unhealed wounds 12 months after proctectomy. We report that unhealed wounds are more common in male patients. Importantly, our results also suggest that exposure to biologics does not affect rates of wound healing.

Normalization of Fecal Calprotectin Within 12 Months of Diagnosis Is Associated With Reduced Risk of Disease Progression in Patients With Crohn's Disease.

BACKGROUND & AIMS: The level of fecal calprotectin (FC) correlates with endoscopic evidence of inflammation in Crohn's disease (CD). A treat-to-target algorithm for patients with CD, that incorporates FC, outperforms a treatment strategy based on symptoms alone in the induction of mucosal healing at 12 months. We investigated whether normalization of FC within 12 months of diagnosis of CD is associated with a reduction in disease progression. METHODS: We performed a retrospective cohort study at a tertiary IBD centre in the United Kingdom. We identified all incident cases of CD diagnosed from 2005 through 2017. Patients with a FC measurement ≥250 µg/g at diagnosis who also had at least 1 follow-up FC measurement within the first 12 months of diagnosis and >12 months of follow up were included. The last FC measurement within 12 months of diagnosis was used to determine normalization (cut-off <250 µg/g). The primary endpoint was time to first disease progression (composite of progression in Montreal disease behavior B1 to B2/3, B2 to B3, or new perianal disease; CD-related surgery; or CD-related hospitalization). Cox proportional hazards regression analysis was used to determine independent factors associated with time to first disease progression. RESULTS: A total of 375 patients out of 1389 incident cases were included, with a median follow up of 5.3 years (interquartile range, 3.1-7.4 years). Normalization of FC within 12 months of diagnosis was confirmed in 43.5% of patients. Patients with normalized levels of FC had a significantly lower risk of composite disease progression (hazard ratio [HR], 0.36; 95% CI, 0.24-0.53; P < .001). They also had a lower risk of reaching any of the separate progression endpoints (progression in Montreal behavior or new perianal disease HR, 0.22; 95% CI, 0.11-0.45; P < .001; hospitalization HR, 0.33; 95% CI, 0.21-0.53; P <.001; surgery HR, 0.39; 95% CI, 0.19-0.78; P = .008) CONCLUSIONS: Normalization of FC within 12 months of diagnosis is associated with a reduced risk of progression of CD.

The ACE (Albumin, CRP and Endoscopy) Index in Acute Colitis: A Simple Clinical Index on Admission that Predicts Outcome in Patients With Acute Ulcerative Colitis.

BACKGROUND: Intravenous (IV) steroids remain the first-line treatment for patients with acute ulcerative colitis (UC). However, 30% of patients do not respond to steroids, requiring second-line therapy and/or surgery. There are no existing indices that allow physicians to predict steroid nonresponse at admission. We aimed to determine if admission biochemical and endoscopic values could predict response to IV steroids. METHODS: All admissions for acute UC (ICD-10 K51) between November 1, 2011, and October 31, 2016 were identified. Case note review confirmed diagnosis; clinical, endoscopic, and laboratory data were collected. Steroid response was defined as discharge home with no further therapy for active UC. Nonresponse was defined as requirement for second-line therapy or surgery. Univariate and binary logistic regression analyses were employed to identify factors associated with steroid nonresponse. RESULTS: Two hundred and thirty-five acute UC admissions were identified, comprising both acute severe and acute nonsevere UC; 155 of the 235 patients (66.0%) responded to steroids. Admission C-reactive protein (CRP) (P = 0.009, odds ratio [OR] 1.006), albumin (P < 0.001, OR 0.894) and endoscopic severity (P < 0.001, OR 3.166) differed significantly between responders and nonresponders. A simple UC severity score (area under the curve [AUC] 0.754, P < 0.001) was derived from these variables; 78.1% (25 of 32) of patients with concurrent CRP ≥50 mg/L, albumin ≤30 g/L, and increased endoscopic severity (severe on physician's global assessment) (maximum score = 3) did not respond to IV steroids (positive predictive value [PPV] 78.1%, negative predictive value [NPV] 87.1%). CONCLUSIONS: More than three quarters of patients scoring 3 (albumin ≤30 g/L, CRP ≥50 mg/L, and increased endoscopic severity) did not respond to IV steroids. This combination of parameters (ACE) identifies on admission a high-risk population who may benefit from earlier second-line medical treatment or surgical intervention.

Analysis of colectomy rates for ulcerative colitis in pre- and postbiological eras in Lothian, Scotland.

AIM: Biological treatment is effective in maintaining remission in ulcerative colitis (UC), although the effect on colectomy rates remains unclear. In the UK the use of antitumour necrosis factor and anti-α4ß7 treatments for maintenance therapy in UC was restricted until 2015. The aim of this study was to describe the impact that this change in the prescribing of biologicals had on colectomy rates for UC. METHOD: All patients (adult and paediatric) with a diagnosis of UC who received maintenance biological treatment and/or underwent a colectomy in Lothian, Scotland between 2005 and 2018 were identified. Linear and segmental regression analyses were used to identify the annual percentage change (APC) and temporal trends (statistical joinpoints) in biological prescription and colectomy rates. RESULTS: Rates of initiation of maintenance biological therapy increased from 0.05 per 100 UC patients in 2005 to 1.26 in 2018 (p < 0.001). Colectomy rates per 100 UC patients fell from 1.47 colectomies in 2005 to 0.44 in 2018 (p < 0.001). The APC for colectomy decreased by 4.1% per year between 2005 and 2014 and by 18.9% between 2014 and 2018. Temporal trend analysis (2005-2018) identified a significant joinpoint in colectomy rates in 2014 (p = 0.019). CONCLUSION: The use of maintenance biological therapy increased sharply following the change in guidance. This has been paralleled by a significant reduction in the rates of colectomy over the same time period.

Consensus standards of healthcare for adults and children with inflammatory bowel disease in the UK.

OBJECTIVE: Symptoms and clinical course during inflammatory bowel disease (IBD) vary among individuals. Personalised care is therefore essential to effective management, delivered by a strong patient-centred multidisciplinary team, working within a well-designed service. This study aimed to fully rewrite the UK Standards for the healthcare of adults and children with IBD, and to develop an IBD Service Benchmarking Tool to support current and future personalised care models. DESIGN: Led by IBD UK, a national multidisciplinary alliance of patients and nominated representatives from all major stakeholders in IBD care, Standards requirements were defined by survey data collated from 689 patients and 151 healthcare professionals. Standards were drafted and refined over three rounds of modified electronic-Delphi. RESULTS: Consensus was achieved for 59 Standards covering seven clinical domains; (1) design and delivery of the multidisciplinary IBD service; (2) prediagnostic referral pathways, protocols and timeframes; (3) holistic care of the newly diagnosed patient; (4) flare management to support patient empowerment, self-management and access to specialists where required; (5) surgery including appropriate expertise, preoperative information, psychological support and postoperative care; (6) inpatient medical care delivery (7) and ongoing long-term care in the outpatient department and primary care setting including shared care. Using these patient-centred Standards and informed by the IBD Quality Improvement Project (IBDQIP), this paper presents a national benchmarking framework. CONCLUSIONS: The Standards and Benchmarking Tool provide a framework for healthcare providers and patients to rate the quality of their service. This will recognise excellent care, and promote quality improvement, audit and service development in IBD.

Association of trough vedolizumab levels with clinical, biological and endoscopic outcomes during maintenance therapy in inflammatory bowel disease.

OBJECTIVE: To establish the relationship between trough vedolizumab levels and outcomes during maintenance therapy. DESIGN: Cross-sectional service evaluation was performed on patients with inflammatory bowel disease (IBD) receiving maintenance vedolizumab therapy (minimum of 12 weeks following induction). Prior to infusion, data on clinical activity (Harvey-Bradshaw Index or partial Mayo score), trough C-reactive protein (CRP)/vedolizumab levels and faecal calprotectin were collected. Endoscopic data (±8 weeks from vedolizumab level testing) were obtained by review of medical records. Vedolizumab levels were processed using the Immundiagnostik monitor ELISA. SETTING: The Edinburgh IBD Unit, Western General Hospital (tertiary IBD referral centre). PATIENTS: Seventy-three patients (30 ulcerative colitis and 43 Crohn's disease) were identified who fulfilled inclusion criteria and had vedolizumab levels matched with clinical activity scores, CRP and faecal calprotectin. Of these, 40 patients also had matched endoscopic data. MAIN OUTCOME MEASURES: The association of trough vedolizumab levels with clinical remission (Harvey-Bradshaw Index <5 or partial Mayo <2), biologic remission (faecal calprotectin <250 µg/g+CRP <5 mg/L) and endoscopic remission (Mayo score 0/no inflammation and ulceration on colonoscopy). RESULTS: The median trough vedolizumab levels were similar between patients in and not in clinical remission (10.6 vs 9.9 µg/mL, p=0.54); biologic remission (10.6 vs 9.8 µg/mL, p=0.35) and endoscopic remission (8.1 vs 10.2 µg/mL, p=0.21). Quartile analysis revealed no significant increase in the proportion of patients in clinical remission, biologic remission or endoscopic remission with increasing trough vedolizumab levels (p<0.05). CONCLUSIONS: In this cohort, trough vedolizumab levels were not associated with clinical, biological or endoscopic outcomes during maintenance therapy.

Higher anti-tumor necrosis factor levels are associated with perianal fistula healing and fistula closure in Crohn's disease.

OBJECTIVE: Limited data are available regarding the relationship between anti-tumor necrosis factor (TNF) drug/antibody levels and perianal fistula outcomes in Crohn's disease. The aims of this study were to assess the relationship between maintenance anti-TNF levels and perianal fistula outcomes. METHODS: This was a retrospective cross-sectional study of patients receiving maintenance adalimumab or infliximab therapy (minimum 24 weeks) for the treatment of Crohn's disease with associated perianal fistulas, who had anti-TNF drug/antibody levels (trough for infliximab) measured within 4 weeks of clinical assessment. The primary outcome was the association of anti-TNF levels with perianal fistula healing defined as the absence of drainage. The secondary outcome was the association of anti-TNF levels with complete perianal fistula closure. RESULTS: A total of 64 patients (adalimumab, n = 35; infliximab, n = 29) were included. Patients with fistula healing had higher levels of anti-TNF vs. those without fistula healing (adalimumab: 12.6 vs. 2.7 µg/mL, P < 0.01; infliximab: 8.1 vs. 3.2 µg/mL, P < 0.01). Patients with fistula closure also had significantly higher anti-TNF levels vs. those without fistula closure (adalimumab: 14.8 vs. 5.7 µg/mL, P < 0.01; infliximab: 8.2 vs. 3.2 µg/mL, P < 0.01). For adalimumab, receiver operator characteristic analysis identified an optimum level of >6.8 µg/mL and >9.8 µg/mL for fistula healing and closure, respectively. For infliximab, receiver operator characteristic analysis identified an optimum trough level of >7.1 µg/mL for both fistula healing and closure. CONCLUSION: Higher maintenance anti-TNF levels are associated with perianal fistula healing and closure in Crohn's disease.

Association Between Level of Fecal Calprotectin and Progression of Crohn's Disease.

BACKGROUND & AIMS: Mucosal healing is associated with improved outcomes in patients with Crohn's disease (CD), but assessment typically requires ileocolonoscopy. Calprotectin can be measured in fecal samples to determine luminal disease activity in place of endoscopy-this measurement is an important component of the treat-to-target strategy. We investigated whether levels of fecal calprotectin are associated with subsequent CD progression. METHODS: We performed a retrospective study of 918 patients with CD (4218 patient-years of follow-up evaluation; median, 50.6 mo; interquartile range [IQR], 32.8-76.0 mo) managed at a tertiary medical center in Edinburgh, United Kingdom, from 2003 through 2015. Patients were included if they had 1 or more fecal calprotectin measurements made 3 months or more after their diagnosis. We collected clinical data and fecal calprotectin measurements and analyzed these data to identify factors associated with a composite outcome of progression in Montreal behavior, hospitalization, and resection. RESULTS: An increased level of fecal calprotectin at the index visit was associated with subsequent progression of CD, independent of symptoms or disease location. The median level of fecal calprotectin at the index visit was 432 µg/g (IQR, 1365-998 µg/g) in patients who reached the composite end point vs 180 µg/g (IQR, 50-665 µg/g) in patients who did not. In multivariable analysis, a cut-off value of 115 µg/g calprotectin identified patients who met the end point with a hazard ratio of 2.4 (95% CI, 1.8-3.1; P < .0001). CONCLUSIONS: In a retrospective analysis of patients with CD, we found that measurements of fecal calprotectin made during routine monitoring can identify patients at risk for disease progression, independent of symptoms or disease location. It is therefore important to screen asymptomatic patients for mucosal inflammation and pursue complete resolution of inflammation.