Low Incidence of Colorectal Advanced Neoplasia During Surveillance in Individuals with a Family History of Colorectal Cancer

BACKGROUND

Family history of colorectal cancer (CRC) is used to stratify individuals into risk categories which determine timing of initial screening and ongoing CRC surveillance. Evidence for long-term CRC risk following a normal index colonoscopy in family history populations is limited.

AIMS

To assess the incidence of advanced neoplasia and associated risk factors in a population undergoing surveillance colonoscopies due to family history of CRC.

METHODS

Surveillance colonoscopy findings were examined in 425 individuals with a family history of CRC, a normal index colonoscopy and a minimum of 10 years of follow-up colonoscopies. Advanced neoplasia risk was determined for three CRC family history categories (near-average, medium and high-risk), accounting for demographics and time after the first colonoscopy.

RESULTS

The median follow-up was 13.5 years (IQR 11.5-16.0), with an incidence of advanced neoplasia of 14.35% (61/425). The number of affected relatives and age of CRC diagnosis in the youngest relative did not predict the risk of advanced neoplasia (p > 0.05), with no significant differences in advanced neoplasia incidence between the family history categories (p = 0.16). Patients ≥ 60 years showed a fourfold (HR 4.14, 95% CI 1.33-12.89) higher advanced neoplasia risk during surveillance than those < 40 years at index colonoscopy. With each subsequent negative colonoscopy, the risk of advanced neoplasia at ongoing surveillance was reduced.

CONCLUSIONS

The incidence of advanced neoplasia was low (14.35%), regardless of the family history risk category, with older age being the main risk for advanced neoplasia. Delaying onset of colonoscopy or lengthening surveillance intervals could be a more efficient use of resources in this population.

Inhibited postprandial retrograde cyclic motor pattern in the distal colon of patients with diarrhea-predominant irritable bowel syndrome

Patients with irritable bowel syndrome (IBS) have recurrent lower abdominal pain, associated with altered bowel habit (diarrhea and/or constipation). As bowel habit is altered, abnormalities in colonic motility are likely to contribute; however, characterization of colonic motor patterns in patients with IBS remains poor. Utilizing fiber-optic manometry, we aimed to characterize distal colonic postprandial colon motility in diarrhea-predominant IBS. After an overnight fast, a 72-sensor (spaced at 1-cm intervals) manometry catheter was colonoscopically placed to the proximal colon, in 13 patients with IBS-D and 12 healthy adults. Recordings were taken for 2 h pre and post a 700 kcal meal. Data were analyzed with our two developed automated techniques. In both healthy adults and patients with IBS-D, the dominant frequencies of pressure waves throughout the colon are between 2 and 4 cycles per minute (cpm) and the power of these frequencies increased significantly after a meal. Although these pressure waves formed propagating contractions in both groups, the postprandial propagating contraction increase was significantly smaller in patients compared with healthy adults. In healthy adults during the meal period, retrograde propagation between 2 and 8 cpm was significantly greater than antegrade propagation at the same frequencies. This difference was not observed in IBS-D. Patients with IBS-D show reduced prevalence of the retrograde cyclic motor pattern postprandially compared with the marked prevalence in healthy adults. We hypothesize that this reduction may allow premature rectal filling, leading to postprandial urgency and diarrhea.NEW & NOTEWORTHY Compared with healthy adults this study has shown a significant reduction in the prevalence of the postprandial retrograde cyclic motor pattern in the distal colon of patients with diarrhea-predominant irritable bowel syndrome. We hypothesize that this altered motility may allow for premature rectal filling which contributes to the postprandial urgency and diarrhea experienced by these patients.

An Extremes of Phenotype Approach Confirms Significant Genetic Heterogeneity in Patients with Ulcerative Colitis

BACKGROUND AND AIMS

Ulcerative colitis [UC] is a major form of inflammatory bowel disease globally. Phenotypic heterogeneity is defined by several variables including age of onset and disease extent. The genetics of disease severity remains poorly understood. To further investigate this, we performed a genome wide association [GWA] study using an extremes of phenotype strategy.

METHODS

We conducted GWA analyses in 311 patients with medically refractory UC [MRUC], 287 with non-medically refractory UC [non-MRUC] and 583 controls. Odds ratios [ORs] were calculated for known risk variants comparing MRUC and non-MRUC, and controls.

RESULTS

MRUC-control analysis had the greatest yield of genome-wide significant single nucleotide polymorphisms [SNPs] [2018], including lead SNP = rs111838972 [OR = 1.82, p = 6.28 × 10-9] near MMEL1 and a locus in the human leukocyte antigen [HLA] region [lead SNP = rs144717024, OR = 12.23, p = 1.7 × 10-19]. ORs for the lead SNPs were significantly higher in MRUC compared to non-MRUC [p < 9.0 × 10-6]. No SNPs reached significance in the non-MRUC-control analysis (top SNP, rs7680780 [OR 2.70, p = 5.56 × 10-8). We replicate findings for rs4151651 in the Complement Factor B [CFB] gene and demonstrate significant changes in CFB gene expression in active UC. Detailed HLA analyses support the strong associations with MHC II genes, particularly HLA-DQA1, HLA-DQB1 and HLA-DRB1 in MRUC.

CONCLUSIONS

Our MRUC subgroup replicates multiple known UC risk variants in contrast to non-MRUC and demonstrates significant differences in effect sizes compared to those published. Non-MRUC cases demonstrate lower ORs similar to those published. Additional risk and prognostic loci may be identified by targeted recruitment of individuals with severe disease.

Quality of colonoscopy performed by medical or surgical specialists and trainees in five Australian hospitals

BACKGROUND

Ensuring colonoscopy procedure quality is vital to the success of screening and surveillance programmes for bowel cancer in Australia. However, the data on the performance of quality metrics, through adequate adenoma detection, bowel preparation, and procedure completion rates, in the Australian public sector is limited. Understanding these can inform quality improvement to further strengthen our capacity for prevention and early detection of colorectal cancer.

AIM

To determine the quality of colonoscopy in Australian teaching hospitals and their association with proceduralist specialty, trainee involvement, and location.

METHODS

We retrospectively evaluated 2443 consecutive colonoscopy procedure reports from 1 January to 1 April, 2018 from five public teaching tertiary hospitals in Australia (median 60 years old, 49% male). Data for bowel preparation quality, procedure completion rates, and detection rates of clinically significant adenomas, conventional adenomas, and serrated lesions was collected and compared to national criteria for quality in colonoscopy. Participating hospital, proceduralist specialty, and trainee involvement indicators were used for stratification. Data was analysed using Chi-squared tests of independence, Mann-Whitney U, One-way ANOVA, and multivariate binary logistic regression.

RESULTS

Fifty-two point two percent (n = 1276) and 43.3% (n = 1057) were performed by medical and surgical proceduralists respectively, whilst 29.8% (n = 728) involved a trainee. Inadequate bowel preparation affected 7.3% of all procedures. The procedure completion rate was 95.1%, which increased to 97.5% after adjustment for bowel preparation quality. The pooled cancer, adenoma, and serrated lesion detection rates for all five hospitals were 3.5%, 40%, and 5.9% respectively. Assessed hospitals varied significantly by patient age (P < 0.001), work-force composition (P < 0.001), adequacy of bowel preparation (P < 0.001), and adenoma detection rate (P < 0.001). Two hospitals (40%) did not meet all national criteria for quality, due to a procedure completion rate of 94.5% or serrated lesion detection rate of 2.6%. Although lower than the other hospitals, the difference was not significant. Compared with surgical specialists, procedures performed by medical specialists involved older patients [65 years (inter-quartile range, IQR 58-73) vs 64 years (IQR 56-71); P = 0.04] and were associated with a higher adenoma detection rate [odds ratio (OR) 1.53; confidence interval: 1.21-1.94; P < 0.001]. Procedures involving trainee proceduralists were not associated with differences in the detection of cancer, adenoma, or serrated lesions, compared with specialists, or according to their medical or surgical background. On multivariate analysis, cancer detection was positively associated with patient age (OR 1.04; P < 0.001) and negatively associated with medical compared to surgical proceduralists (OR 0.54; P = 0.04). Conventional adenoma detection rates were independently associated with increasing patient age (OR 1.04; P < 0.001), positively associated with medical compared to surgical proceduralists (OR 1.41; P = 0.002) and negatively associated with male gender (OR 0.53; P < 0.001).

CONCLUSION

Significant differences in the quality of colonoscopy in Australia exist, even when national benchmarks are achieved. The role of possible contributing factors, like procedural specialty and patient gender need further evaluation.

The influence of the surveillance time interval on the risk of advanced neoplasia after non-advanced adenoma removal

OBJECTIVES

To investigate the incidence of advanced neoplasia (colorectal cancer or advanced adenoma) at surveillance colonoscopy following removal of non-advanced adenoma; to determine whether the time interval before surveillance colonoscopy influences the likelihood of advanced neoplasia.

DESIGN

Retrospective cohort study.

SETTING, PARTICIPANTS

Patients enrolled in a South Australian surveillance colonoscopy program with findings of non-advanced adenoma during 1999-2016 who subsequently underwent surveillance colonoscopy.

MAIN OUTCOME MEASURES

Incidence of advanced neoplasia at follow-up surveillance colonoscopy.

RESULTS

Advanced neoplasia was detected in 169 of 965 eligible surveillance colonoscopies (18%) for 904 unique patients (median age, 62.0 years; interquartile range [IQR], 54.0-69.0 years), of whom 570 were men (59.1%). The median interval between the initial and surveillance procedures was 5.2 years (IQR, 4.4-6.0 years; range, 2.0-14 years). Factors associated with increased risk of advanced neoplasia at follow-up included age (per year: odds ratio [OR], 1.03; 95% CI, 1.01-1.05), prior history of adenoma (OR, 1.48; 95% CI, 1.01-2.15), two non-advanced adenomas identified at baseline procedure (v one: OR, 1.74; 95% CI, 1.18-2.57), and time to surveillance colonoscopy (OR, 1.21; 95% CI, 1.08-1.37). The estimated incidence of advanced neoplasia was 19% five years after non-advanced adenoma removal, and 30% at ten years.

CONCLUSIONS

Increasing the surveillance colonoscopy interval beyond five years after removal of non-advanced adenoma increases the risk of detection of advanced neoplasia at follow-up colonoscopy.

Level of UV Exposure, Skin Type, and Age Are More Important than Thiopurine Use for Keratinocyte Carcinoma Development in IBD Patients

BACKGROUND

Retrospective studies observe an increased risk of keratinocyte carcinomas (KCs) in patients with inflammatory bowel disease (IBD) on thiopurine (TP) medication. The role of traditional risk factors such as skin type and sun protection behavior has not been studied in this population. This study aimed to examine traditional KC risk factors and thiopurine use on skin cancer development in an IBD cohort.

METHODS

Consecutive IBD patients were recruited from four specialist centers in Australia and New Zealand, each with varying UV exposure indices. Data pertaining to race, skin color, freckling and sun protection behavior, dose of TP therapy, and skin cancer development were elicited through a self-reported questionnaire.

RESULTS

A total of 691 IBD patients were included with 62 reporting KC development. Thiopurine usage was similar among patients who developed skin cancer compared with those who did not (92% vs. 89%, p = 0.3). There was no statistically significant association between KC development and TP dose or 6-thioguanine nucleotide levels. In multivariate modeling, four factors were independently and significantly associated with KC: age over 61 years old versus less than 30 years old (OR 6.76; 95% CI 2.38-19.18), residing in Brisbane versus Christchurch (OR 3.3; 95% CI 1.6-6.8), never staying in the shade versus staying in the shade ≥ 50% of the time (OR 3.8; 95% CI 1.4-10.5), and having a skin type that never tanned versus other skin types (OR 6.9; 95% CI 2.9-16.0).

CONCLUSION

Skin type, age, and sun protection behavior are more important risk factors for KC development than thiopurine medication use in this IBD population.

Anti-TNF Therapeutic Drug Monitoring in Postoperative Crohn's Disease

BACKGROUND

Anti-TNF prevents postoperative Crohn's disease recurrence in most patients but not all. This study aimed to define the relationship between adalimumab pharmacokinetics, maintenance of remission and recurrence.

METHODS

As part of a study of postoperative Crohn's disease management, some patients undergoing resection received prophylactic postoperative adalimumab. In these patients, serum and fecal adalimumab concentration and serum anti-adalimumab antibodies [AAAs] were measured at 6, 12 and 18 months postoperatively. Levels of Crohn's disease activity index [CDAI], C-reactive protein [CRP] and fecal calprotectin [FC] were assessed at 6 and 18 months postoperatively. Body mass index and smoking status were recorded. A colonoscopy was performed at 6 and/or 18 months.

RESULTS

Fifty-two patients [32 on monotherapy and 20 on combination therapy with thiopurine] were studied. Adalimumab concentration did not differ significantly between patients in endoscopic remission vs recurrence [Rutgeerts ≥ i2] [9.98µg/mL vs 8.43 µg/mL, p = 0.387]. Patients on adalimumab monotherapy had a significantly lower adalimumab concentration [7.89 µg/mL] than patients on combination therapy [11.725 µg/mL] [p = 0.001], and were significantly more likely to have measurable AAA [31% vs 17%, p = 0.001]. Adalimumab concentrations were lower in patients with detectable AAA compared with those without [3.59 µg/mL vs 12.0 µg/mL, p < 0.001]. Adalimumab was not detected in fecal samples. Adalimumab serum concentrations were lower in obese patients compared with in non-obese patients [p = 0.046].

CONCLUSION

Adalimumab concentration in patients treated with adalimumab to prevent symptomatic endoscopic recurrence postoperatively is, for most patients, well within the therapeutic window, and is not significantly lower in patients who develop recurrence compared with in those who remain in remission. Mechanisms of anti-TNF failure to prevent postoperative recurrence remain to be determined in these patients.

Toward More Efficient Surveillance of Barrett's Esophagus: Identification and Exclusion of Patients at Low Risk of Cancer

BACKGROUND

Endoscopic surveillance of Barrett's esophagus (BE) is probably not cost-effective. A sub-population with BE at increased risk of high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) who could be targeted for cost-effective surveillance was sought.

METHODS

The outcome for BE surveillance from 2003 to 2012 in a structured program was reviewed. Incidence rates and incidence rate ratios for developing HGD or EAC were calculated. Risk stratification identified individuals who could be considered for exclusion from surveillance. A health-state transition Markov cohort model evaluated the cost-effectiveness of focusing on higher-risk individuals.

RESULTS

During 2067 person-years of follow-up of 640 patients, 17 individuals progressed to HGD or EAC (annual IR 0.8%). Individuals with columnar-lined esophagus (CLE) ≥2 cm had an annual IR of 1.2% and >8-fold increased relative risk of HGD or EAC, compared to CLE <2 cm [IR-0.14% (IRR 8.6, 95% CIs 4.5-12.8)]. Limiting the surveillance cohort after the first endoscopy to individuals with CLE ≥2 cm, or dysplasia, followed by a further restriction after the second endoscopy-exclusion of patients without intestinal metaplasia-removed 296 (46%) patients, and 767 (37%) person-years from surveillance. Limiting surveillance to the remaining individuals reduced the incremental cost-effectiveness ratio from US$60,858 to US$33,807 per quality-adjusted life year (QALY). Further restrictions were tested but failed to improve cost-effectiveness.

CONCLUSIONS

Based on stratification of risk, the number of patients requiring surveillance can be reduced by at least a third. At a willingness-to-pay threshold of US$50,000 per QALY, surveillance of higher-risk individuals becomes cost-effective.

Serologic antibodies in relation to outcome in postoperative Crohn's disease

BACKGROUND AND AIM

Disease recurs frequently after Crohn's disease resection. The role of serological antimicrobial antibodies in predicting recurrence or as a marker of recurrence has not been well defined.

METHODS

A total of 169 patients (523 samples) were prospectively studied, with testing peri-operatively, and 6, 12 and 18 months postoperatively. Colonoscopy was performed at 18 months postoperatively. Serologic antibody presence (perinuclear anti-neutrophil cytoplasmic antibody [pANCA], anti-Saccharomyces cerevisiae antibodies [ASCA] IgA/IgG, anti-OmpC, anti-CBir1, anti-A4-Fla2, anti-Fla-X) and titer were tested. Quartile sum score (range 6-24), logistic regression analysis, and correlation with phenotype, smoking status, and endoscopic outcome were assessed.

RESULTS

Patients with ≥ 2 previous resections were more likely to be anti-OmpC positive (94% vs 55%, ≥ 2 vs < 2, P = 0.001). Recurrence at 18 months was associated with anti-Fla-X positivity at baseline (49% vs 29%; positive vs negative, P = 0.033) and 12 months (52% vs 31%, P = 0.04). Patients positive (n = 28) for all four antibacterial antibodies (anti-CBir1, anti-OmpC, anti-A4-Fla2, and anti-Fla-X) at baseline were more likely to experience recurrence at 18 months than patients negative (n = 32) for all four antibodies (82% vs 18%, P = 0.034; odds ratio 6.4, 95% confidence interval 1.16-34.9). The baseline quartile sum score for all six antimicrobial antibodies was higher in patients with severe recurrence (Rutgeert's i3-i4) at 18 months, adjusted for clinical risk factors (odds ratio 1.16, 95% confidence interval 1.01-1.34, P = 0.039). Smoking affected antibody status.

CONCLUSIONS

Anti-Fla-X and presence of all anti-bacterial antibodies identifies patients at higher risk of early postoperative Crohn's disease recurrence. Serologic screening pre-operatively may help identify patients at increased risk of recurrence.

Outcomes and patients’ perspectives of transition from paediatric to adult care in inflammatory bowel disease

AIM: To describe the disease and psychosocial outcomes of an inflammatory bowel disease (IBD) transition cohort and their perspectives.

METHODS: Patients with IBD, aged > 18 years, who had moved from paediatric to adult care within 10 years were identified through IBD databases at three tertiary hospitals. Participants were surveyed regarding demographic and disease specific data and their perspectives on the transition process. Survey response data were compared to contemporaneously recorded information in paediatric service case notes. Data were compared to a similar age cohort who had never received paediatric IBD care and therefore who had not undergone a transition process.

RESULTS: There were 81 returned surveys from 46 transition and 35 non-transition patients. No statistically significant differences were found in disease burden, disease outcomes or adult roles and responsibilities between cohorts. Despite a high prevalence of mood disturbance (35%), there was a very low usage (5%) of psychological services in both cohorts. In the transition cohort, knowledge of their transition plan was reported by only 25/46 patients and the majority (54%) felt they were not strongly prepared. A high rate (78%) of discussion about work/study plans was recorded prior to transition, but a near complete absence of discussion regarding sex (8%), and other adult issues was recorded. Both cohorts agreed that their preferred method of future transition practices (of the options offered) was a shared clinic appointment with all key stakeholders.

CONCLUSION: Transition did not appear to adversely affect disease or psychosocial outcomes. Current transition care processes could be optimised, with better psychosocial preparation and agreed transition plans.

Efficacy of thiopurines and adalimumab in preventing Crohn's disease recurrence in high-risk patients - a POCER study analysis

BACKGROUND

Crohn's disease recurs in the majority of patients after intestinal resection.

AIM

To compare the relative efficacy of thiopurines and anti-TNF therapy in patients at high risk of disease recurrence.

METHODS

As part of a larger study comparing post-operative management strategies, patients at high risk of recurrence (smoker, perforating disease, ≥2nd operation) were treated after resection of all macroscopic disease with 3 months metronidazole together with either azathioprine 2 mg/kg/day or mercaptopurine 1.5 mg/kg/day. Thiopurine-intolerant patients received adalimumab induction then 40 mg fortnightly. Patients underwent colonoscopy at 6 months with endoscopic recurrence assessed blind to treatment.

RESULTS

A total of 101 patients [50% male; median (IQR) age 36 (25-46) years] were included. There were no differences in disease history between thiopurine- and adalimumab-treated patients. Fifteen patients withdrew prior to 6 months, five due to symptom recurrence (of whom four were colonoscoped). Endoscopic recurrence (Rutgeerts score i2-i4) occurred in 33 of 73 (45%) thiopurine vs. 6 of 28 (21%) adalimumab-treated patients [intention-to-treat (ITT); P = 0.028] or 24 of 62 (39%) vs. 3 of 24 (13%) respectively [per-protocol analysis (PPA); P = 0.020]. Complete mucosal endoscopic normality (Rutgeerts i0) occurred in 17/73 (23%) vs. 15/28 (54%) (ITT; P = 0.003) and in 27% vs. 63% (PPA; P = 0.002). The most advanced disease (Rutgeerts i3 and i4) occurred in 8% vs. 4% (thiopurine vs. adalimumab).

CONCLUSIONS

In Crohn's disease patients at high risk of post-operative recurrence adalimumab is superior to thiopurines in preventing early disease recurrence.

Effect of intestinal resection on quality of life in Crohn's disease

INTRODUCTION

Patients with Crohn's disease have poorer health-related quality of life [HRQoL] than healthy individuals, even when in remission. Although HRQoL improves in patients who achieve drug-induced or surgically induced remission, the effects of surgery overall have not been well characterised.

METHODS

In a randomised trial, patients undergoing intestinal resection of all macroscopically diseased bowel were treated with postoperative drug therapy to prevent disease recurrence. All patients were followed prospectively for 18 months. C-reactive protein [CRP], Crohn's Disease Activity Index [CDAI], and faecal calprotectin [FC] were measured preoperatively and at 6, 12, and 18 months. HRQoL was assessed with a general [SF36] and disease-specific [IBDQ] questionnaires at the same time points.

RESULTS

A total of 174 patients were included. HRQoL was poor preoperatively but improved significantly [p < 0.001] at 6 months postoperatively. This improvement was sustained at 18 months. Females and smokers had a poorer HRQoL when compared with males and non-smokers, respectively. Persistent endoscopic remission, intensification of drug treatment at 6 months, and anti-tumour necrosis factor therapy were not associated with HRQoL outcomes different from those when these factors were not present. There was a significant inverse correlation between CDAI, [but not endoscopic recurrence, CRP, or FC] on HRQoL.

CONCLUSION

Intestinal resection of all macroscopic Crohn's disease in patients treated with postoperative prophylactic drug therapy is associated with significant and sustained improvement in HRQoL irrespective of type of drug treatment or endoscopic recurrence. HRQoL is lower in female patients and smokers. A higher CDAI, but not direct measures of active disease or type of drug therapy, is associated with a lower HRQoL.

Factors affecting faecal immunochemical test positive rates: demographic, pathological, behavioural and environmental variables

OBJECTIVES

Positive rates in faecal immunochemical test (FIT)-based colorectal cancer screening programmes vary, suggesting that differences between programmes may affect test results. We examined whether demographic, pathological, behavioural, and environmental factors affected haemoglobin concentration and positive rates where samples are mailed.

METHODS

A retrospective cohort study; 34,298 collection devices were sent, over five years, to screening invitees (median age 60.6). Participant demographics, temperature on sample postage day, and previous screening were recorded. Outcomes from colonoscopy performed within a year following FIT were collected. Multivariate logistic regression identified significant predictors of test positivity.

RESULTS

Higher positive rate was independently associated with male gender, older age, lower socioeconomic status, and distally located neoplasia, and negatively associated with previous screening (p < 0.05). Older males had higher faecal haemoglobin concentrations and were less likely to have a false positive result at colonoscopy (p < 0.05). High temperature on the sample postage day was associated with reduced haemoglobin concentration and positivity rate (26-35℃: Odds ratio 0.78, 95% confidence interval 0.66-0.93), but was not associated with missed significant neoplasia at colonoscopy (p > 0.05).

CONCLUSIONS

Haemoglobin concentrations, and therefore FIT positivity, were affected by factors that vary between screening programmes. Participant demographics and high temperature at postage had significant effects. The impact of temperature could be reduced by seasonal scheduling of invitations. The importance of screening, and following up positive test results, particularly in older males, should be promoted.

Measurement of fecal calprotectin improves monitoring and detection of recurrence of Crohn's disease after surgery

BACKGROUND & AIMS

Crohn's disease (CD) usually recurs after intestinal resection; postoperative endoscopic monitoring and tailored treatment can reduce the chance of recurrence. We investigated whether monitoring levels of fecal calprotectin (FC) can substitute for endoscopic analysis of the mucosa.

METHODS

We analyzed data collected from 135 participants in a prospective, randomized, controlled trial, performed at 17 hospitals in Australia and 1 hospital in New Zealand, that assessed the ability of endoscopic evaluations and step-up treatment to prevent CD recurrence after surgery. Levels of FC, serum levels of C-reactive protein (CRP), and Crohn's disease activity index (CDAI) scores were measured before surgery and then at 6, 12, and 18 months after resection of all macroscopic Crohn's disease. Ileocolonoscopies were performed at 6 months after surgery in 90 patients and at 18 months after surgery in all patients.

RESULTS

Levels of FC were measured in 319 samples from 135 patients. The median FC level decreased from 1347 μg/g before surgery to 166 μg/g at 6 months after surgery, but was higher in patients with disease recurrence (based on endoscopic analysis; Rutgeerts score, ≥i2) than in patients in remission (275 vs 72 μg/g, respectively; P < .001). Combined 6- and 18-month levels of FC correlated with the presence (r = 0.42; P < .001) and severity (r = 0.44; P < .001) of CD recurrence, but the CRP level and CDAI score did not. Levels of FC greater than 100 μg/g indicated endoscopic recurrence with 89% sensitivity and 58% specificity, and a negative predictive value (NPV) of 91%; this means that colonoscopy could have been avoided in 47% of patients. Six months after surgery, FC levels less than 51 μg/g in patients in endoscopic remission predicted maintenance of remission (NPV, 79%). In patients with endoscopic recurrence at 6 months who stepped-up treatment, FC levels decreased from 324 μg/g at 6 months to 180 μg/g at 12 months and 109 μg/g at 18 months.

CONCLUSIONS

In this analysis of data from a prospective clinical trial, FC measurement has sufficient sensitivity and NPV values to monitor for CD recurrence after intestinal resection. Its predictive value might be used to identify patients most likely to relapse. After treatment for recurrence, the FC level can be used to monitor response to treatment. It predicts which patients will have disease recurrence with greater accuracy than CRP level or CDAI score.

Crohn's disease management after intestinal resection: a randomised trial

BACKGROUND

Most patients with Crohn's disease need an intestinal resection, but a majority will subsequently experience disease recurrence and require further surgery. This study aimed to identify the optimal strategy to prevent postoperative disease recurrence.

METHODS

In this randomised trial, consecutive patients from 17 centres in Australia and New Zealand undergoing intestinal resection of all macroscopic Crohn's disease, with an endoscopically accessible anastomosis, received 3 months of metronidazole therapy. Patients at high risk of recurrence also received a thiopurine, or adalimumab if they were intolerant to thiopurines. Patients were randomly assigned to parallel groups: colonoscopy at 6 months (active care) or no colonoscopy (standard care). We used computer-generated block randomisation to allocate patients in each centre to active or standard care in a 2:1 ratio. For endoscopic recurrence (Rutgeerts score ≥i2) at 6 months, patients stepped-up to thiopurine, fortnightly adalimumab with thiopurine, or weekly adalimumab. The primary endpoint was endoscopic recurrence at 18 months. Patients and treating physicians were aware of the patient's study group and treatment, but central reading of the endoscopic findings was undertaken blind to the study group and treatment. Analysis included all patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov, number NCT00989560.

FINDINGS

Between Oct 13, 2009, and Sept 28, 2011, 174 (83% high risk across both active and standard care groups) patients were enrolled and received at least one dose of study drug. Of 122 patients in the active care group, 47 (39%) stepped-up treatment. At 18 months, endoscopic recurrence occurred in 60 (49%) patients in the active care group and 35 (67%) patients in the standard care group (p=0.03). Complete mucosal normality was maintained in 27 (22%) of 122 patients in the active care group versus four (8%) in the standard care group (p=0.03). In the active care arm, of those with 6 months recurrence who stepped up treatment, 18 (38%) of 47 patients were in remission 12 months later; conversely, of those in remission at 6 months who did not change therapy recurrence occurred in 31 (41%) of 75 patients 12 months later. Smoking (odds ratio [OR] 2.4, 95% CI 1.2-4.8, p=0.02) and the presence of two or more clinical risk factors including smoking (OR 2.8, 95% CI 1.01-7.7, p=0.05) increased the risk of endoscopic recurrence. The incidence and type of adverse and severe adverse events did not differ significantly between patients in the active care and standard care groups (100 [82%] of 122 vs 45 [87%] of 52; p=0.51) and (33 [27%] of 122 vs 18 [35%] of 52; p=0.36), respectively.

INTERPRETATION

Treatment according to clinical risk of recurrence, with early colonoscopy and treatment step-up for recurrence, is better than conventional drug therapy alone for prevention of postoperative Crohn's disease recurrence. Selective immune suppression, adjusted for early recurrence, rather than routine use, leads to disease control in most patients. Clinical risk factors predict recurrence, but patients at low risk also need monitoring. Early remission does not preclude the need for ongoing monitoring.

FUNDING

AbbVie, Gutsy Group, Gandel Philanthropy, Angior Foundation, Crohn's Colitis Australia, and the National Health and Medical Research Council.

Colonic motor abnormalities in slow transit constipation defined by high resolution, fibre-optic manometry

BACKGROUND

Slow transit constipation (STC) is associated with colonic motor abnormalities. The underlying cause(s) of the abnormalities remain poorly defined. In health, utilizing high resolution fiber-optic manometry, we have described a distal colonic propagating motor pattern with a slow wave frequency of 2-6 cycles per minute (cpm). A high calorie meal caused a rapid and significant increase in this activity, suggesting the intrinsic slow wave activity could be mediated by extrinsic neural input. Utilizing the same protocol our aim was to characterize colonic meal response STC patients.

METHODS

A fiber-optic manometry catheter (72 sensors at 1 cm intervals) was colonoscopically placed with the tip clipped at the ascending or transverse colon, in 14 patients with scintigraphically confirmed STC. Manometric recordings were taken, for 2 h pre and post a 700 kCal meal. Data were compared to 12 healthy adults.

KEY RESULTS

Prior to and/or after the meal the cyclic propagating motor pattern was identified in 13 of 14 patients. However, the meal, did not increase the cyclic motor pattern (preprandial 7.4 ± 7.6 vs postprandial 8.3 ± 4.5 per/2 h), this is in contrast to the dramatic increase observed in health (8.3 ± 13.3 vs 59.1 ± 89.0 per/2 h; p < 0.001).

CONCLUSIONS & INFERENCES

In patients with STC a meal fails to induce the normal increase in the distal colonic cyclic propagating motor patterns. We propose that these data may indicate that the normal extrinsic parasympathetic inputs to the colon are attenuated in these patients.

Allopurinol use in pregnancy in three women with inflammatory bowel disease: safety and outcomes: a case series

Background

Allopurinol is a frequently prescribed drug. In inflammatory bowel disease patients who shunt thiopurine metabolism towards more toxic and less desirable pathways, allopurinol is proving to be an effective add on therapy with good resultant disease control and less treatment side effects. As many such patients are young, the potential for pregnant women to be exposed to allopurinol is increasing. The safety of allopurinol in pregnancy is not known however.

Case presentation

We report three cases of safe use of allopurinol in pregnancy for women with inflammatory bowel disease. This included 2 patients with ulcerative colitis and 1 patient with fistulising Crohn’s disease. Allopurinol was used throughout pregnancy in all patients. All 3 pregnancies resulted in normal healthy babies born at term by Caesarean section.

Conclusion

It is important to evaluate and document the safety of allopurinol during pregnancy, as it is finding new roles in young patients. These three cases add significantly to the very limited data on allopurinol use in pregnancy. We encourage reporting of all cases of allopurinol use in pregnant patients and suggest an allopurinol pregnancy registry to document drug exposures and outcomes.

Thiopurine metabolite measurement leads to changes in management of inflammatory bowel disease

BACKGROUND

The thiopurines azathioprine and 6-mercaptopurine are recommended for maintenance of remission in inflammatory bowel disease (IBD). Measurement of concentrations of the metabolites 6-thioguanine nucleotide and 6-methylmercaptopurine helps delineate interindividual variation in metabolism that may underlie variability in efficacy and toxicity.

AIMS

We aimed to perform a retrospective observational study to determine the utility of thiopurine metabolite testing following its introduction into South Australia.

METHODS

All patients having thiopurine metabolite tests done at Flinders Medical Centre between November 2008 and January 2010 were identified. Case notes of patients with testing done in the context of treatment for IBD were interrogated to determine the reason for testing, clinical context and outcome.

RESULTS

One hundred and fifty-one patients were identified with thiopurine metabolite testing for IBD with 157 testing episodes. Eighty (51.0%) had testing done for flare or inefficacy, 18 (11.5%) for adverse effects, 5 (3.2%) for a combination of inefficacy and adverse effects, and 54 (34.4%) for routine or other reasons. Testing was followed by improved outcomes of increased efficacy, reduced toxicity or change to alternative therapy in 55.0% of the inefficacy/flare group, 27.8% of the suspected adverse reaction group, 60.0% of the combination group, and 13.0% of the routine/other group. Allopurinol was used as cotherapy in 16 patients and led to marked improvements in metabolite concentrations.

CONCLUSIONS

Thiopurine metabolite testing has quickly become established in South Australia. When used for inefficacy or adverse effects, it often leads to improved outcomes. Prospective studies are needed to determine whether routine testing to guide dosing is of benefit.

Crohn's disease and smoking: is it ever too late to quit?

BACKGROUND

Smoking increases CD risk. The aim was to determine if smoking cessation at, prior to, or following, CD diagnosis affects medication use, disease phenotypic progression and/or surgery.

METHODS

Data on CD patients with disease for ≥5 yrs were collected retrospectively including the Montreal classification, smoking history, CD-related abdominal surgeries, family history, medication use and disease behaviour at diagnosis and the time when the disease behaviour changed.

RESULTS

1115 patients were included across six sites (mean follow-up-16.6 yrs). More non-smokers were male (p=0.047) with A1 (p<0.0001), L4 (p=0.028) and perianal (p=0.03) disease. Non-smokers more frequently received anti-TNF agents (p=0.049). (p=0.017: OR 2.5 95%CI 1.18-5.16) and those who ceased smoking prior to diagnosis (p=0.045: OR 2.3 95%CI 1.02-5.21) progressed to complicated (B2/B3) disease as compared to those quitting at diagnosis. Patients with uncomplicated terminal ileal disease at diagnosis more frequently developed B2/B3 disease than isolated colonic CD (p<0.0001). B2/B3 disease was more frequent with perianal disease (p<0.0001) and if i.v. steroids (p=0.004) or immunosuppressants (p<0.0001) were used. 49.3% (558/1115) of patients required at least one intestinal surgery. More smokers had a 2nd surgical resection than patients who quit at, or before, the 1st resection and non-smokers (p=0.044: HR=1.39 95%CI 1.01-1.91). Patients smoking >3 cigarettes/day had an increased risk of developing B2/B3 disease (p=0.012: OR 3.8 95%CI 1.27-11.17).

CONCLUSION

Progression to B2/B3 disease and surgery is reduced by smoking cessation. All CD patients regardless of when they were diagnosed, or how many surgeries, should be strongly encouraged to cease smoking.

Shift to earlier stage at diagnosis as a consequence of the National Bowel Cancer Screening Program

OBJECTIVE

To assess the impact of the National Bowel Cancer Screening Program (NBCSP) in South Australia.

DESIGN, SETTING AND PARTICIPANTS

A cohort comparison of colorectal cancer (CRC) patient data from the NBCSP register and the South Australian Cancer Registry. Patient records of those invited to take part in screening through the NBCSP, those who participated in the program, and those with positive test results were compared with those of the rest of the study population (excluding the group of interest) on an intention-to-screen basis.

MAIN OUTCOME MEASURE

Stage of CRC at diagnosis as a surrogate marker for effect on CRC mortality.

RESULTS

Of 3481 eligible patients, 221 had been invited to the NBCSP. Invitees were more likely to have stage A lesions compared with all other patients (34.8% versus 19.2%; P < 0.001), and half as likely to have stage D CRC (5.4% versus 12.4%; P < 0.001). A further shift towards earlier stage was seen in those who participated in screening and those with positive test results compared with all other patients (38.8% stage A and 3.0% stage D in screening participants versus 19.3% stage A and 12.4% stage D in all other patients; and 39.7% stage A and 2.6% stage D in those with positive test results versus 19.3% stage A and 12.4% stage D in all other patients; P < 0.001).

CONCLUSIONS

CRCs were diagnosed at a significantly earlier stage in people invited to the NBCSP compared with those who were not invited, regardless of participation status or test result. The NBCSP should lead to reductions in CRC mortality in Australia.

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.

Screening for colorectal cancer and advanced colorectal neoplasia in kidney transplant recipients: cross sectional prevalence and diagnostic accuracy study of faecal immunochemical testing for haemoglobin and colonoscopy

OBJECTIVE

To investigate whether screening kidney transplant recipients aged over 50 years for colorectal cancer with a faecal immunochemical test for haemoglobin might be justified, by determining the prevalence of advanced colorectal neoplasia and evaluating the diagnostic accuracy of faecal haemoglobin testing compared with colonoscopy in a population of kidney transplant recipients at otherwise average risk.

DESIGN

Cross sectional prevalence and diagnostic accuracy study with index test of faecal haemoglobin and reference standard of colonoscopy.

SETTING

Outpatient clinics in metropolitan and regional hospitals in South Australia.

PARTICIPANTS

229 kidney transplant recipients aged 50 years and over, who were at least 6 months (mean 9.0 (SD 8.4) years) post-transplant and otherwise at average risk of colorectal cancer, completed the study between June 2008 and October 2011.

INTERVENTIONS

Faecal immunochemical testing (Enterix Insure) for human haemoglobin, followed by colonoscopy with histological evaluation of retrieved samples.

MAIN OUTCOME MEASURES

Prevalence of advanced colorectal neoplasia, defined as an adenoma at least 10 mm in diameter, villous features, high grade dysplasia, or colorectal cancer; sensitivity, specificity, and predictive values of faecal haemoglobin testing for advanced neoplasia compared with colonoscopy.

RESULTS

Advanced colorectal neoplasia was found in 29 (13%, 95% confidence interval 9% to 18%) participants, including 2% (n=4) with high grade dysplasia and 2% (n=5) with colorectal cancer. Faecal testing for haemoglobin was positive in 12% (n=28); sensitivity, specificity, and positive and negative predictive values for advanced neoplasia were 31.0% (15.3% to 50.8%), 90.5% (85.6% to 94.2%), 32.1% (15.9% to 52.4%), and 90.1% (85.1% to 93.8%). Colonoscopy was well tolerated, with no significant adverse outcomes. To identify one case of advanced neoplasia, 8 (6 to 12) colonoscopies were needed.

CONCLUSIONS

Kidney transplant recipients aged over 50 years have a high prevalence of advanced colorectal neoplasia. Faecal haemoglobin screening for colorectal neoplasia has similar performance characteristics in transplant recipients to those reported in general population studies, with poor sensitivity but reasonable specificity. Surveillance colonoscopy might be a more appropriate approach in this population.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12608000154303.

Interval fecal immunochemical testing in a colonoscopic surveillance program speeds detection of colorectal neoplasia

BACKGROUND & AIMS

Rapidly progressing or missed lesions can reduce the effectiveness of colonoscopy-based colorectal cancer surveillance programs. We investigated whether giving fecal immunochemical tests (FITs) for hemoglobin between surveillance colonoscopies resulted in earlier detection of neoplasia.

METHODS

The study included 1736 patients with a family history or past neoplasia; they received at least 2 colonoscopy examinations and were followed for a total of 8863 years. Patients were excluded from the study if they had genetic syndromes, colorectal surgery, or inflammatory bowel disease. An FIT was offered yearly, in the interval between colonoscopies; if results were positive, the colonoscopy was performed earlier than scheduled.

RESULTS

Among the 1071 asymptomatic subjects (61%) who received at least 1 FIT, the test detected 12 of 14 cancers (86% sensitivity) and 60 of 96 (63%) advanced adenomas. In patients with positive results from the FIT, the diagnosis of cancer was made 25 months (median) earlier and diagnosis of advanced adenoma 24 months earlier. Patients who had repeated negative results from FIT had an almost 2-fold decrease in risk for cancer and advanced adenoma compared with patients who were not tested (5.5% vs 10.1%, respectively, P = .0004). The most advanced stages of neoplasia, observed across the continuum from nonadvanced adenoma to late-stage cancer, were associated with age (increased with age), sex (increased in males), and FIT result. The probability of most advanced neoplastic stage was lowest among those with a negative result from the FIT (odds ratio, 0.68; P < .001).

CONCLUSIONS

Interval examinations using the FIT detected neoplasias sooner than scheduled surveillances. Subjects with negative results from the FIT had the lowest risk for the most advanced stage of neoplasia. Interval FIT analyses can be used to detect missed or rapidly developing lesions in surveillance programs.

Serious infections in patients with inflammatory bowel disease receiving anti-tumor-necrosis-factor-alpha therapy: an Australian and New Zealand experience

BACKGROUND AND AIM

Anti-tumor-necrosis-factor-alpha (anti-TNF-α) medications are effective in inflammatory bowel disease (IBD), but have an increased risk of tuberculosis (TB) and serious infections. The aim of this study was to examine the Australian/New Zealand experience of serious infections and TB in IBD patients receiving anti-TNF-α therapy from 1999-2009.

METHODS

Serious infections, defined as 'requiring hospital admission' and TB cases in patients receiving, or within 3 months following, anti-TNF-α therapy were analyzed across Australia and New Zealand. Patient demographics, IBD medications, duration of anti-TNF-α therapy, and infection details were collected.

RESULTS

A total of 5562 IBD patients were managed across the centers. Of these, 489 (16.8%) Crohn's disease and 137 (5.2%) ulcerative colitis patients received anti-TNF-α therapy. There were three cases of latent TB that received prophylaxis prior to anti-TNF-α therapy. No cases of active TB were reported. Fourteen (2.2%) serious infections occurred. Seven occurred in patients receiving anti-TNF-α therapy for less than 6 months, including two cases of primary Varicella zoster (VZV), two cases of Pneumocystis jiroveci pneumonia, two cases of Staphylococcus aureus bacteremia, and one severe flu-like illness. Six patients were taking additional immunosuppressive medications. The other seven infections occurred after 6 months (mean 32.6 ± 24.3 months) and included one case of primary VZV, one flu-like illness, and five bacterial infections. All infections resolved with treatment.

CONCLUSION

TB is a very rare complication of anti-TNF-α therapy in Australia and New Zealand. Serious infections are uncommon but early opportunistic infections with Pneumocystis jiroveci pneumonia suggest a need for vigilance in patients on multiple immunosuppressive medications. VZV vaccination prior to immunosuppressive therapy should be considered in VZV-naïve patients.

Clinical trial: the impact of cyclooxygenase inhibitors on gastrointestinal recovery after major surgery - a randomized double blind controlled trial of celecoxib or diclofenac vs. placebo

BACKGROUND

Ileus occurs after abdominal surgery and may be severe. Inhibition of prostaglandin release reduces post-operative ileus in a rat model.

AIM

To determine whether prostaglandin inhibition by cyclooxygenase inhibitors, celecoxib or diclofenac, could enhance gastrointestinal recovery and reduce post-operative ileus in humans.

METHODS

Two hundred and ten patients undergoing elective major abdominal surgery were randomized to receive twice daily placebo (n = 67), celecoxib (100 mg, n = 74) or diclofenac (50 mg, n = 69), preoperatively and continuing for up to 7 days. Primary outcomes were hallmarks of gut recovery. Secondary outcomes were paralytic ileus, pain and complications.

RESULTS

There was no clinically significant difference between the groups for restoration of bowel function. There was a significant reduction in paralytic ileus in the celecoxib-treated group (n = 1, 1%) compared with diclofenac (n = 7, 10%) and placebo (n = 9, 13%); P = 0.025, RR 0.20, CI 0.01-0.77. Pain scores, analgesia, transfusion requirements and adverse event rates were similar between study groups.

CONCLUSIONS

Perioperative low dose celecoxib, but not diclofenac, markedly reduced the development of paralytic ileus following major abdominal surgery, but did not accelerate early recovery of bowel function. This was independent of narcotic use and had no increase in post-operative complications.

Un-promoted issues in inflammatory bowel disease: opportunities to optimize care

Inflammatory bowel diseases (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), are chronic inflammatory disorders of the gut, which lead to significant morbidity and impaired quality of life (QoL) in sufferers, without generally affecting mortality. Despite CD and UC being chronic, life-long illnesses, most medical management is directed at acute flares of disease. Moreover, with more intensive medical therapy and the development of biological therapy, there is a risk that management will become even more narrowly focused on acute care, and be directed only at those with more severe disease, rather than encompassing all sufferers and addressing important non-acute issues. This imbalance of concentration of medical attention on 'high-end' care is in part driven by the need to perform and publish randomized clinical trials of newer therapies to obtain registration and licensing for these agents, which thus occupy a large proportion of the recent IBD treatment literature. This leads to less attention on relatively 'low-technology' issues including: (i) the psychosocial burden of chronic disease, QoL and specific psychological comorbidities; (ii) comorbidity with functional gastrointestinal disorders (FGIDs); (iii) maintenance therapy, monitoring and compliance; (iv) smoking (with regard to CD); (v) sexuality, fertility, family planning and pregnancy; and (vi) iron deficiency and anaemia. We propose these to be the 'Un-promoted Issues' in IBD and review the importance and treatment of each of these in the current management of IBD.

Un-promoted issues in inflammatory bowel disease: opportunities to optimize care

Inflammatory bowel diseases (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), are chronic inflammatory disorders of the gut, which lead to significant morbidity and impaired quality of life (QoL) in sufferers, without generally affecting mortality. Despite CD and UC being chronic, life-long illnesses, most medical management is directed at acute flares of disease. Moreover, with more intensive medical therapy and the development of biological therapy, there is a risk that management will become even more narrowly focused on acute care, and be directed only at those with more severe disease, rather than encompassing all sufferers and addressing important non-acute issues. This imbalance of concentration of medical attention on 'high-end' care is in part driven by the need to perform and publish randomized clinical trials of newer therapies to obtain registration and licensing for these agents, which thus occupy a large proportion of the recent IBD treatment literature. This leads to less attention on relatively 'low-technology' issues including: (i) the psychosocial burden of chronic disease, QoL and specific psychological comorbidities; (ii) comorbidity with functional gastrointestinal disorders (FGIDs); (iii) maintenance therapy, monitoring and compliance; (iv) smoking (with regard to CD); (v) sexuality, fertility, family planning and pregnancy; and (vi) iron deficiency and anaemia. We propose these to be the 'Un-promoted Issues' in IBD and review the importance and treatment of each of these in the current management of IBD.

Achieving long-term compliance with colonoscopic surveillance guidelines for patients at increased risk of colorectal cancer in Australia

We have previously demonstrated that we could improve colonoscopic surveillance practice for patients at increased risk of colorectal cancer by the adoption of guidelines, facilitated by a nurse co-ordinator. This study was to determine whether we could sustain this improvement over a longer period (4 years). All colonoscopic surveillance decisions made by the co-ordinated colorectal screening programme of our hospital between 2000 and April 2004 were reviewed. Reasons for variance were recorded, and surveillance decisions made in the last 4 months of the study time were compared with decisions made 4 years previously, both before and after the introduction of the co-ordinated programme. Between 2000 and 2004, 1794 surveillance decisions were made with variance occurring in 100. In the last 4 months of the period of study, 98% of decisions matched guidelines, suggesting that the improvement made following the adoption of the guidelines (45-96% p < 0.05) could be maintained. Reasons for variance from guidelines included a belief that the particular clinical scenario was not covered in the guidelines, disagreement with the guidelines or patient anxiety. Adherence to evidence based medicine guidelines for colonoscopy surveillance can be maintained over time at a high level. A number of clinical scenarios are not covered adequately by the existing guidelines and continue to generate disagreement amongst clinicians.

Many participants in fecal occult blood test population screening have a higher-than-average risk for colorectal cancer

OBJECTIVES

Population-based colorectal cancer screening by fecal occult blood testing reduces cancer-specific mortality. Current guidelines recommend this strategy for average risk individuals. This study investigated the prevalence of higher-than-average risk characteristics, and rate of prior colonoscopy, in participants in fecal occult blood test screening programs.

METHODS

Randomly selected individuals aged 50-74 years in urban Adelaide were offered free fecal occult blood test screening by mail, without prior knowledge of their medical status. Each invitation included a questionnaire to record the prevalence of higher-than-average risk characteristics related to symptoms, family history or comorbidity, as well as prior colonoscopy. The definition of average risk was taken from updated guidelines published by the US Multisociety Task Force on Colorectal Cancer.

RESULTS

Of 2538 responses analyzed, 425 individuals had had a colonoscopy within the last 5 years, 106 fulfilled family history criteria for an initial screening colonoscopy, 209 had past polyps and 26 had had colorectal cancer. Eighty-three reported recent rectal bleeding. By current guidelines, 23% of the screened population did not warrant fecal occult blood test, because either prior colonoscopy rendered it unnecessary or particular patient characteristics made colonoscopy a more appropriate initial investigation.

CONCLUSIONS

Fecal occult blood test screening programs capture a sizeable number of higher-than-average risk individuals that may warrant colonoscopic rather than fecal occult blood test screening. Other participants have had a recent colonoscopy and probably warrant a delay in screening. Mass population fecal occult blood test-based screening programs need to more effectively target those at average risk and should divert those of higher or lower risk to more individualized assessment.

Improving surveillance for Barrett's oesophagus

PROBLEM

A retrospective audit of surveillance for Barrett's oesophagus 1996-2001 identified the need to improve adherence to guidelines for the endoscopic surveillance of patients with Barrett's oesophagus.

DESIGN

Prospective audit of the effect of disseminating guidelines in 2002. Prospective audit of the effect of introducing local guidelines and Barrett's oesophagus surveillance officers, 2003-2005.

SETTING

Two general hospitals in Australia, 2002-5. All adult patients diagnosed with Barrett's oesophagus were included.

KEY MEASURES FOR IMPROVEMENT

Proportions of patients in a Barrett's oesophagus surveillance programme who had appropriate time intervals between follow-up endoscopies and who had appropriate numbers of biopsies collected at endoscopy.

STRATEGIES FOR CHANGE

Local guidelines were laid down. Surveillance coordinators for Barrett's oesophagus were introduced to manage the process according to a clinical protocol designed for each patient.

EFFECTS OF CHANGE

Disseminating guidelines had little effect on practice. Six months after surveillance coordinators were introduced, adherence to the planned surveillance interval increased from 17% to 92% and the number of endoscopies at which sufficient biopsies were collected increased from 45% to 83%. These changes have been maintained.

LESSONS LEARNT

Disseminating guidelines and results of an audit on endoscopic surveillance in Barrett's oesophagus had no effect on practice. Introducing coordinators who proactively managed the process greatly improved adherence to guidelines.

Impaired proximal colonic motor response to rectal mechanical and chemical stimulation in obstructed defecation

PURPOSE

Both motor and sensory dysfunction have been implicated in the pathogenesis of obstructed defecation. We have found that despite preservation of a defecatory urge, patients with obstructed defecation have lost the normal predefecatory augmentation in frequency and amplitude of colonic propagating pressure waves. This observation might be explainable by either altered rectal sensory thresholds or by dysfunction in the colonic motor apparatus. By measuring rectal sensory thresholds and proximal colonic motor responses to rectal mechanical and chemical stimuli, we tested the hypotheses that central perception of rectal stimuli is enhanced and that the proximal colonic motor response to rectal stimulation is attenuated.

METHODS

In seven patients with obstructed defecation and ten healthy volunteers we measured proximal colonic motor responses and sensory thresholds in response to both rectal balloon distention and rectal instillation of chenodeoxycholic acid.

RESULTS

In controls, but not in patients, rectal mechanical distention significantly reduced and chemical stimulation significantly increased the frequency of proximal colonic propagating sequences (P = 0.01). There was no significant difference in rectal sensory thresholds between patients and controls. Prior instillation of chenodeoxycholic acid significantly reduced (P < 0.03) maximum tolerated balloon volume and defecatory urge volume to comparable degree in both patients and controls.

CONCLUSIONS

In obstructed defecation, 1) the normal rectocolonic pathways mediating stimulation-induced proximal colonic propagating pressure waves are nonfunctioning, and. 2) central perception of these rectal stimuli is normal.

Interval faecal occult blood testing in a colonoscopy based screening programme detects additional pathology

BACKGROUND

Colonoscopic based surveillance is recommended for patients at increased risk of colorectal cancer. The appropriate interval between surveillance colonoscopies remains in debate, as is the "miss rate" for colorectal cancer within such screening programmes.

AIMS

The main aim of this study was to determine whether a one-off interval faecal occult blood test (FOBT) facilitates the detection of significant neoplasia within a colonoscopic based surveillance programme. Secondary aims were to determine if invitees were interested in participating in interval screening, and to determine whether interval lesions were missed or whether they developed rapidly since the previous colonoscopy

PATIENTS

Patients enrolled in a colonoscopic based screening programme due to a personal history of colorectal neoplasia or a significant family history.

METHODS

Patients within the screening programme were invited to perform an immunochemical FOBT (Inform). A positive result was followed by colonoscopy; significant neoplasia was defined as colorectal cancer, adenomas either > or =10 mm or with a villous component, high grade dysplasia, or multiplicity (>/=3 adenomas). Participation rates were determined for age, sex, and socioeconomic subgroups. Colonoscopy recall databases were examined to determine the interval between previous colonoscopy and FOBT offer, and correlations between lesion characteristics and interval time were determined.

RESULTS

A total of 785 of 1641 patients invited (47.8%) completed an Inform kit. A positive result was recorded for 57 (7.3%). Fifty two of the 57 test positive patients completed colonoscopy; 14 (1.8% of those completing the FOBT) had a significant neoplastic lesion. These consisted of six colorectal cancers and eight significant adenomas.

CONCLUSIONS

A one off immunochemical faecal occult blood test within a colonoscopy based surveillance programme had a participation rate of nearly 50% and appeared to detect additional pathology, especially in patients with a past history of colonic neoplasia.

Abnormal predefecatory colonic motor patterns define constipation in obstructed defecation

BACKGROUND & AIMS

The pathophysiology of constipation in the syndrome of obstructed defecation is unknown. Using 24-hour pancolonic manometric recordings of the unprepared colon to record basal pressures and spontaneous defecation episodes, we tested the hypothesis that the frequency, timing, or spatial distribution of propagating colonic pressure waves is abnormal in patients with obstructed defecation.

METHODS

In 11 patients with obstructed defecation and 16 healthy controls, pressures were recorded using a nasocolonic catheter that was positioned such that 16 recording sites spanned the unprepared colon at 7.5-cm intervals.

RESULTS

The overall frequency of propagating sequences (PS) in the colon did not differ between patients and controls. When compared with controls, patients had a significant increase in the frequency of retrograde and antegrade PS (P < 0.05) in the left colon and a significant reduction in the amplitude of propagating pressure waves throughout the entire colon (P < 0.03). Defecation occurred in 6 of 11 patients and 9 of 16 controls. In the 15 minutes before defecation, controls showed a highly significant increase in frequency (P = 0.001) and amplitude (P = 0.01) of PS. In contrast, patients did not demonstrate this or the typical spatiotemporal organization of PS normally observed before expulsion of stool.

CONCLUSIONS

Patients with obstructed defecation lack the normal predefecatory augmentation in frequency and amplitude of propagating pressure waves and lack the normal stereotypic spatiotemporal patterning of colonic pressure waves that would normally culminate in effective expulsion of stool.

The proximal colonic motor response to rectal mechanical and chemical stimulation

We aimed to determine whether rectal distension and/or infusion of bile acids stimulates propagating or nonpropagating activity in the unprepared proximal colon in 10 healthy volunteers using a nasocolonic manometric catheter (16 recording sites at 7.5-cm spacing). Sensory thresholds and proximal colonic motor responses were assessed following rectal distension by balloon inflation and rectal instillation of chenodeoxycholic acid. Maximum tolerated balloon volume and the volume that stimulated a desire to defecate were both significantly (P < 0.01) reduced after rectal chenodeoxycholic acid. The frequency of colonic propagating pressure wave sequences decreased significantly in response to initial balloon inflations (P < 0.05), but the frequency doubled after subsequent chenodeoxycholic acid infusion (P < 0.002). Nonpropagating activity decreased after balloon inflation, was not influenced by acid infusion, and demonstrated a further decrease in response to repeat balloon inflation. We concluded that rectal chenodeoxycholic acid in physiological concentrations is a potent stimulus for propagating pressure waves arising in the proximal colon and reduces rectal sensory thresholds. Rectal distension inhibits all colonic motor activity.

Applying evidence-based guidelines improves use of colonoscopy resources in patients with a moderate risk of colorectal neoplasia

OBJECTIVES

To determine whether applying National Health and Medical Research Council (NHMRC) guidelines for colorectal cancer prevention would reduce the number of follow-up colonoscopies.

DESIGN

A prospective audit of colonoscopic surveillance decisions before and after the intervention.

SETTING

The endoscopy suite at a metropolitan tertiary hospital three months before and after January 2000.

INTERVENTION

Dissemination of NHMRC guidelines, and supervision of application of the guidelines by a nurse coordinator.

SUBJECTS

We compared colonoscopic surveillance decisions before and after the intervention in two groups of 100 consecutive patients after polypectomy and in two groups of 50 consecutive patients with a family history of colorectal cancer after a normal colonoscopy.

MAIN OUTCOME MEASURES

Change in concordance of decisions with NHMRC guidelines; and effect on number of follow-up colonoscopies.

RESULTS

After the intervention, the proportion of postpolypectomy surveillance decisions matching the guidelines increased from 37% to 96% (P < 0.05). The mean time to repeat colonoscopy after polypectomy increased from 2.7 to 3.5 years (P < 0.005) (ie, a 23% reduction in the number of postpolypectomy surveillance colonoscopies performed per year). Likewise, the proportion of family-history surveillance decisions matching the guidelines increased from 63% to 96%. Adhering to the guidelines resulted in a 17% reduction in colonoscopies performed on the basis of a family history of colorectal cancer.

CONCLUSIONS

Supervised application of evidence-based guidelines to a colorectal cancer surveillance program significantly reduces the number of surveillance colonoscopies performed.

Prolonged multi-point recording of colonic manometry in the unprepared human colon: providing insight into potentially relevant pressure wave parameters

OBJECTIVES

To determine the feasibility of and derive normative data for prolonged, 24-h, multipoint, closely spaced, water perfused manometry of the unprepared human colon.

METHODS

In 14 healthy volunteers, 24-h recordings were made using a water perfused, balloon-tipped, 17 lumen catheter which was passed pernasally and positioned so that 16 recording sites spanned the colon at 7.5 cm intervals from cecum to rectum. The area under the pressure curve and propagating pressure wave parameters were quantified for the 16 regions. High amplitude propagating sequences were defined as were rectal motor complexes.

RESULTS

Nasocolonic recording was well tolerated and achievable. Propagation sequences, including high amplitude propagating sequences, originated in the cecum (0.32 +/- 0.05/h) more frequently than in other regions and the extent of propagation correlated significantly with proximity of the site of sequence origin to the cecum (p < 0.001). Propagation velocity of propagating sequences was greater than high amplitude propagating sequences (p = 0.0002) and region-dependent, unlike high amplitude propagating sequences (p < 0.01). The frequency of propagating sequences did not increase after the meal, but frequency of high amplitude propagating sequences was increased significantly by the meal (p < 0.01). Rectal motor complexes were seen throughout the colon with no apparent periodicity.

CONCLUSIONS

Prolonged, multipoint, perfusion manometry of the unprepared colon provides improved spatial resolution of colonic motor patterns and confirms the diurnal and regional variations in propagating pressure waves detected in the prepared colon. The study demonstrates differences between high amplitude propagating sequences and propagating sequence parameters that may have functional significance; and also, that the rectal motor complex is a ubiquitous pan colonic motor pattern.

Spatial and temporal organization of pressure patterns throughout the unprepared colon during spontaneous defecation

OBJECTIVE

The aim of this study was to examine colonic motor events associated with spontaneous defecation in the entire unprepared human colon under physiological conditions.

METHODS

In 13 healthy volunteers a perfused, balloon-tipped, 17-lumen catheter (outer diameter, 3.5 mm; intersidehole spacing, 7.5 cm) was passed pernasally and positioned in the distal unprepared colon.

RESULTS

In the hour before spontaneous defecation, there was an increase in propagating sequence frequency (p = 0.04) and nonpropagating activity when compared to basal conditions (p < 0.0001). During this hour the spatial and temporal relationships among propagating sequences demonstrated a biphasic pattern. Both the early (proximal) and late (distal) colonic phases involved the whole colon and were characterized by respective antegrade and retrograde migration of site-of-origin of arrays of propagating sequences. There was a negative correlation between propagating sequence amplitude and the time interval from propagating sequence to stool expulsion (p = 0.008).

CONCLUSIONS

The colonic motor correlate of defecation is the colonic propagating sequence, the frequency and amplitude of which begin to increase as early as 1 h before stool expulsion. During the preexpulsive phase, the spatial and temporal relationship among the sites of origin of individual propagating sequences demonstrate a stereotypic anal followed by orad migration, which raises the possibility of control by long colocolonic pathways.

Relationship between terminal ileal pressure waves and propagating proximal colonic pressure waves

The relationship between propagating distal ileal and proximal colonic motor patterns has not been systematically examined in humans. Our aim was to define the relationships, if any, between prolonged propagating contractions or discrete clustered contractions and cecal propagating sequences using multiple manometric recording sites spanning the distal ileum and unprepared colon. In 14 healthy volunteers, a 17-lumen-perfused silicon catheter was positioned pernasally such that at least three recording sites lay in the ileum and the remainder in the colon. Intersidehole distance was 7.5 cm. In 271 h of recording, 30% of the terminal ileal propagating events was temporally associated with cecal propagating sequences. Significantly more prolonged propagating contractions (11 of 24, 46%; P = 0.02) were associated with cecal propagating sequences than were associated with ileal discrete clustered contractions (4 of 26, 15%). This trend was more pronounced at night. Of 159 cecal propagating sequences, 15 (9%) were preceded by an ileal propagating event. The remaining 91% was preceded by increased nonpropagating activity commencing 2 min before the cecal propagating sequence (P = 0.0002). We conclude that distal ileal propagating motor patterns are one stimulus for cecal propagating sequences, with the association being stronger for prolonged propagating contractions than for discrete clustered contractions.

Basal pressure patterns and reflexive motor responses in the human ileocolonic junction

This study aimed to determine whether a sustained high-pressure zone exists at the human ileocolonic junction (ICJ) and whether the motor responses of ICJ are consistent with sphincteric function. In 10 subjects with temporary ileostomies, a high-pressure zone was identified using a manometric pull-through with a mean pressure of 9. 7 +/- 3.2 mmHg and length of 4.8 +/- 1.2 cm. Prolonged recordings using a sleeve sensor confirmed sustained tone in the ICJ and superimposed phasic pressure waves (4-8 counts/min) occupying 35% of fasted state. A meal increased ICJ tone (P = 0.0001) and the proportion of time occupied by phasic activity to 50% (P = 0.013). Terminal ileal propagating pressure wave sequences inhibited ICJ phasic activity, and sequences not extending to the cecum reduced ICJ tone (9.0 +/- 7.2 to 5.6 +/- 6.3 mmHg; P = 0.04). Cecal distension increased ICJ tone (8.9 +/- 4.4 mmHg to 11.7 +/- 4.9 mmHg; P = 0.005). The ICJ response to ileal distension was variable and depended on resting tone at the time of distension. We conclude that the human ICJ has sustained tone with superimposed phasic activity. Tone is augmented by cecal distension or a meal and is inhibited by ileal propagating pressure waves. Response to ileal distension is variable but suggests control by descending excitatory and inhibitory pathways.

A comparison of transnasal and transoral oesophagogastroduodenoscopy

Transnasal oesophagogastroduodenoscopy (OGD) with a narrow-bore endoscope has been demonstrated to be feasible in unsedated volunteers. The aim of the study was to compare efficacy, safety, patient tolerance and costs between this novel approach to OGD and standard sedated OGD. Sixty day patients were enrolled for either sedated transoral endoscopy with a standard calibre endoscope or for unsedated transnasal endoscopy with a narrow-bore (5.3 mm diameter) endoscope. Visualization was unsatisfactory in one examination in each group. The only complications were minor epistaxis in four of the transnasal group and oxygen desaturation below 90% in two of the sedated transoral group. On a 1 (very uncomfortable) to 5 (very comfortable) visual analogue scale, the mean transnasal group score was 3.09, compared with 3.86 in the transoral group (P = 0.013). In the transnasal group, mean procedure room time was 15 min compared with 20 min in the transoral group (P < 0.0003), and mean recovery room time was 7 min compared with 37 min (P < 0.0001). Consumable and pharmaceutical costs were reduced by 65 and 92%, respectively. This study demonstrates that unsedated transnasal OGD is a safe and effective route for OGD and has acceptable patient tolerance. The safety and decreased recovery times offer major cost savings and the potential for this method of OGD to become an office procedure for the investigation of the upper gastrointestinal tract.

A prospective study of the gastroenterological causes of iron deficiency anaemia in a general hospital

BACKGROUND

Current practice is to investigate routinely both upper and lower gastrointestinal tracts in patients with unexplained iron deficiency anaemia.

AIMS

To determine the efficacy of this approach and whether the use of more stringent biochemical criteria for iron deficiency, symptoms, or a positive immunochemical faecal human haemoglobin (FHH) influenced the findings of the investigations and could help target investigations more efficiently.

METHODS

Eighty patients were studied prospectively, 51 who had "definite' iron deficiency anaemia (low ferritin and transferrin saturation) and 29 with "probable' iron deficiency anaemia (either low ferritin or transferrin saturation). Patients underwent a standardised symptom assessment and testing for FHH, upper endoscopy with small bowel biopsy and colonoscopy, and a small bowel series if upper endoscopy and colonoscopy were negative.

RESULTS

Lesions potentially causative for iron deficiency anemia were found in 54/80 (60%) of patients. Five patients (7%) had lesions in both upper and lower tracts. Small bowel biopsy was abnormal in one of 80 patients and small bowel series one of 25 patients. Significant lesions in either the upper or lower gastrointestinal tract were found in 14/20 patients with positive FHH and 25/47 with negative FHH. Symptoms, use of non-steroidal anti-inflammatory drugs and classification of patients into "definite' and "probable' iron deficiency did not influence yield of investigations or site of lesions found.

CONCLUSIONS

Gastrointestinal lesions are common in patients with unexplained iron deficiency anaemia. Neither symptoms nor presence of FHH predict the presence of site of detectable lesions and neither testing for FHH nor more stringent biochemical criteria for iron deficiency alters clinical decision making. The findings support the routine performance of both upper endoscopy and colonoscopy in the investigation of patients with unexplained iron deficiency anaemia, however routine investigation of the small bowel is of questionable value.