Inflammatory bowel disease detection and monitoring by measuring biomarkers in non-invasively collected colorectal mucus

BACKGROUND AND AIM

Non-invasive detection and monitoring of inflammatory bowel disease (IBD) is an important clinical challenge. Stool calprotectin is the most popular among available options, but the necessity of stool collection limits its acceptability. This study aimed to evaluate biomarker measurement in non-invasively collected colorectal mucus as a new tool for IBD detection and activity monitoring.

METHODS

Calprotectin, eosinophil-derived neurotoxin (EDN), and protein S100A12 were measured in colorectal mucus self-collected following defecation by 58 patients with IBD (before therapy), 50 patients with irritable bowel syndrome, and 33 healthy volunteers. Patients with IBD also collected samples at days 10, 20, and 30 of treatment for disease activity monitoring.

RESULTS

Protein biomarker levels were significantly (P < 0.001) higher in IBD patients than in irritable bowel syndrome and control groups. Calprotectin and EDN effectively detected IBD with a respective sensitivity and specificity of 0.76 and 0.92 for calprotectin and 0.83 and 0.94 for EDN. S100A12 was less sensitive. Calprotectin and EDN results were combined in a new test (CALEDN) that had a sensitivity of 0.91 and a specificity of 0.89. Repeated biomarker measurement during IBD treatment demonstrated a steady decline of calprotectin and EDN levels as well as CALEDN values in patients responding to applied therapy and lack of this pattern in non-responders.

CONCLUSIONS

Measuring calprotectin and EDN in non-invasively collected colorectal mucus presents a simple and efficient method for IBD detection and monitoring. Excellent performance of EDN for this purpose is reported for the first time. Combining calprotectin and EDN in one test improves IBD detection sensitivity.

Effects of eosinophilic oesophagitis on quality of life in an adult UK population: a case control study

Eosinophilic oesophagitis (EoE) is a chronic immune-mediated esophageal disease, characterized by symptoms related to esophageal dysfunction and histologically by eosinophil predominant inflammation. Current evidence for an adverse impact on quality of life (QoL) is conflicting and there are no data from a UK population regarding QoL. We conducted a prospective cross-sectional observational study using the Short Form-36 Health Survey, Hospital Dysphagia/Odynophagia Questionnaire, and the EoE Adult Quality of Life Questionnaire to assess QoL and severity of dysphagia in EoE patients, compared to age and gender matched healthy control subjects. Data were also collected on comorbidity and medication use. Eighty-eight subjects were recruited (44 patients). Patients had higher rates of antihistamine and topical (swallowed) corticosteroid use. Physical QoL did not differ between patients and controls, although patients did report a statistically significant lower mental QoL, with small absolute magnitude of difference. Patients reported higher dysphagia scores and these were negatively correlated with both physical and mental QoL. Higher rates of dysphagia and medication use in patients may among other things account for lower mental QoL. However, a higher rate of dysphagia in patients is not associated with a reduced physical QoL. Our findings are of clinical value, particularly when a new diagnosis of EoE is made, as clinicians can reassure patients that their general physical health should not be greatly affected by the diagnosis. Moreover, it may also be useful for patients to be aware that EoE may have an impact on their mental health, but this effect is likely to be small. We therefore advocate education and reassurance in this respect for all patients at diagnosis.

Steroid dependency and trends in prescribing for inflammatory bowel disease - a 20-year national population-based study

BACKGROUND

It is unclear whether adherence to prescribing standards has been achieved in inflammatory bowel disease (IBD).

AIM

To determine how prescribing of 5-aminosalicylates (5-ASAs), steroids and thiopurines has changed in response to emerging evidence.

METHODS

We examined trends in oral and topical therapies in 23 509 incident IBD cases (6997 with Crohn's disease and 16 512 with ulcerative colitis) using a nationally representative sample between 1990 and 2010. We created five eras according to the year of diagnosis: era 1 (1990-1993), era 2 (1994-1997), era 3 (1998-2001), era 4 (2002-2005) and era 5 (2006-2010). We calculated the proportion of patients treated with prolonged 5-ASAs (>12 months) and steroid dependency, defined as prolonged steroids (>3 months) or recurrent (restarting within 3 months) steroid exposure. We calculated the cumulative probability of receiving each medication using survival analysis.

RESULTS

Half of the Crohn's disease patients were prescribed prolonged oral 5-ASAs during the study, although this decreased between era 3 and 5 from 61.8% to 56.4% (P = 0.002). Thiopurine use increased from 14.0% to 47.1% (P < 0.001) between era 1 and 5. This coincided with a decrease in steroid dependency from 36.5% to 26.8% (P < 0.001) between era 1 and 2 and era 4 and 5 respectively. In ulcerative colitis, 49% of patients were maintained on prolonged oral 5-ASAs. Despite increasing thiopurine use, repeated steroid exposure increased from 15.3% to 17.8% (P = 0.02) between era 1 and 2 and era 4 and 5 respectively.

CONCLUSIONS

Prescribing in clinical practice insufficiently mirrors the evidence base. Physicians should direct management towards reducing steroid dependency and optimising 5-ASA use in patients with IBD.

Assessment of cytology and mucin 2 in colorectal mucus collected from patients with inflammatory bowel disease: Results of a pilot trial

BACKGROUND AND AIM

Non-invasive diagnosis of colorectal disease remains problematic, fecal biomarkers presenting the only current option. Colorectal mucus is the diagnostically informative element of stool samples, but its separation from stool is difficult. We aimed to: (i) test a novel method of non-invasive colorectal mucus sampling in a pilot clinical trial; (ii) evaluate sampling method acceptance by study participants; (iii) characterize the collected material cytologically; and (iv) assess feasibility of quantitative protein analysis in the samples.

METHODS

A total of 141 patients with IBD (58), IBS (50), and healthy controls (33) participated in the study. Samples rich in colorectal mucus were self-collected by swabbing the anal area immediately following defecation. Collected samples were examined cytologically and subjected to quantitative analysis for total protein and mucin 2 (MUC2).

RESULTS

The novel sampling technique was assessed as "good" or "adequate" by 96% of study participants. A total of 55% of the collected samples were free of fecal contamination. Cytology showed large numbers of well preserved inflammatory cells in IBD cases. Total protein values varied in all groups, being affected by fecal contamination. MUC2 levels were similar among all IBD-free individuals (control and IBS groups) and elevated in IBD patients (p < 0.001). MUC2 measurement applied as a test for IBD detection provided sensitivity = 72.4% and specificity = 86.7%.

CONCLUSIONS

A novel non-invasive method for collecting human colorectal mucus has been successfully tested. The method was very well accepted by trial participants. The results have proven high quality of collected samples for both cytological investigation and diagnostic biomarker analysis.

Colorectal mucus non-invasively collected from patients with inflammatory bowel disease and its suitability for diagnostic cytology

Colorectal mucus is a key component of the protective gut barrier which is altered in inflammatory bowel disease (IBD). We aimed to cytologically characterize colorectal mucus non-invasively collected from IBD patients using our new sampling technique. Colorectal mucus was self-collected by 58 IBD patients comprising 31 ulcerative colitis (UC) and 27 Crohn's disease (CD) cases. The samples were examined cytologically, and immunocytochemically. Large numbers of well-preserved granulocytes were typically detected (neutrophils undergoing degradation were observed as well). Plasma cells and erythrophagocytosis were present in 18.2% and 29.1% of cases, respectively, predominantly in patients with UC and distal CD. Immunocytochemical visualization of calprotectin in neutrophils, eosinophil-derived neurotoxin in eosinophils and tumour necrosis factor-α in macrophages was also achieved. Correct cytological diagnosis was made in 61.8% of analysed IBD cases. Our new method of colorectal mucus sampling provides highly informative material for cytology. Findings of the presence of plasmocytes and erythrophagocytosis in colorectal mucus are unique and may reflect previously unknown mechanisms of IBD pathogenesis. Immunocytochemical detection of inflammation biomarkers demonstrates the suitability of this material for biomarker quantification. These promising results suggest a potential role for colorectal mucus cytology in the non-invasive diagnosis of IBD.

Impact of early thiopurines on surgery in 2770 children and young people diagnosed with inflammatory bowel disease: a national population-based study

BACKGROUND

The role of early thiopurine treatment in inflammatory bowel disease (IBD) is unproven.

AIM

To quantify the impact of timing and duration of thiopurines on the risk of first surgery in children and young people with IBD using a population-based cohort.

METHODS

We constructed an incident cohort of children and young people aged <25 years, diagnosed with Crohn's disease (CD) or ulcerative colitis (UC) from 1990 to 2009. We used Cox proportional hazards modelling to determine the impact of early thiopurine use, commenced within a year of diagnosis on risk of first surgery.

RESULTS

We identified 1595 and 1175 incident cases of CD and UC respectively with a mean length of follow-up of 4.3 years/person. There were 216 (13.5%) and 73 (6.2%) surgeries for CD and UC patients between 1990 and 2009 respectively. In CD among thiopurine users, the absolute risk of surgery at 5 years for early thiopurine use vs. late was 15.3% (95% CI: 10.5-22.1) vs. 22.1% (95% CI: 18.1-26.9) respectively. After adjustment, the early use of thiopurines was associated with a reduction in risk of first surgery of 39% (HR 0.61, 95% CI: 0.41-0.91) over the 20-year study period. In UC, early thiopurine use offered no additional benefit.

CONCLUSIONS

In Crohn's disease, early treatment with thiopurines in children and young people is associated with an appreciable reduction in the risk of surgery, but early treatment does not reduce surgical risk in UC.

Differences in intestinal metaplasia in Barrett's esophagus patients in an ethnically diverse south London population

Barrett's esophagus (BE) is the replacement of any portion of the normal distal squamous epithelial mucosa by metaplastic columnar epithelium and is the only known precursor for esophageal adenocarcinoma. We undertook a study to identify ethnic differences for the presence of intestinal metaplasia (IM) in BE in patients in an ethnically diverse south London population. Retrospective analysis was done using the endoscopy database of St George's Hospital NHS Trust, which serves a large ethnically diverse London population. Gastroscopy records between 2009 and 2012 were retrieved, and patients with an endoscopic diagnosis of BE were identified. Patients of Indian subcontinent Asian origin (ISCA) were further identified. The presence of IM was retrieved from hospital pathology databases and was the primary outcome measured. Multivariate logistic regression analysis was performed to determine the odds of having IM by ethnic origin. ISCAs were 70% less likely to have IM compared to non-ISCAs (OR 0.32, 95% CI: 0.16-0.61, p = 0.001). This is the first study to identify differences in histological findings in ISCAs with BE living in the UK. Our findings may be useful for the future risk stratification of BE patients. Identification of environmental factors responsible for this difference would be of great therapeutic value.

Small intestinal contrast ultrasonography for the detection of small bowel complications in Crohn's disease: correlation with intraoperative findings and magnetic resonance enterography

BACKGROUND AND AIMS

In evaluating small bowel Crohn's disease (CD), small intestine contrast-enhanced ultrasonography (SICUS) is emerging as an alternative to magnetic resonance enterography (MRE). This retrospective study compared the diagnostic accuracy of SICUS and MRE with surgical findings, and their level of agreement.

METHODS

We identified a cohort of CD patients investigated by either SICUS and/or MRE that subsequently required resective bowel surgery within 6 months. The accuracy and agreement of SICUS and MRE to detect small bowel complications were compared with intraoperative findings using kappa coefficient (κ). Agreement between SICUS and MRE in those undergoing both modalities was also assessed.

RESULTS

A total of 67 patients were evaluated; 25 underwent SICUS and 17 underwent MRE prior to surgery. Another 25 patients underwent both SICUS and MRE. When compared with intraoperative findings, the sensitivity of SICUS and MRE was 87.5% and 100%, respectively, in detecting strictures, 87.7% and 66.7% for fistulae, 100% for both in identifying abscesses, 100% and 66.7% for bowel dilatation, and 94.7% and 81.8% in defining bowel wall thickening. When correlating SICUS and MRE with surgery, there was a high level of agreement in localizing strictures (κ = 0.75, 0.88, respectively), fistulae (κ = 0.82, 0.79) and abscesses (κ = 0.87, 0.77). Concordance between SICUS and MRE was substantial or almost complete in identifying stricturing disease (κ = 0.84), their number and location (κ = 0.85), fistulae (κ = 0.65), and mucosal thickening (κ = 0.61).

CONCLUSION

SICUS accurately identified small bowel complications and correlated well with MRE and intraoperative findings. SICUS offers an alternative in the preoperative assessment of CD.

The impact of timing and duration of thiopurine treatment on colectomy in ulcerative colitis: a national population-based study of incident cases between 1989-2009

BACKGROUND

The role of thiopurines in altering the risk of colectomy in ulcerative colitis (UC) remains unclear.

AIMS

To examine predictors of colectomy in UC and determine the impact of thiopurines on the risk of colectomy.

METHODS

We constructed a population-based cohort of incident cases of UC in the United Kingdom between 1989 and 2009. We determined trends in thiopurine usage and colectomy for three defined cohorts: era 1 (1989-1995), era 2 (1996-2002), era 3 (2003-2009). We used Cox regression to determine predictors of colectomy and quantified the impact of duration and timing of thiopurine use on the risk of colectomy.

RESULTS

We identified 8673 incident cases of UC. 5-year colectomy rates increased from 4.2%, 5.1% to 6.9% (P = 0.001) for era 1, era 2 and era 3, respectively, despite increasing thiopurine use. This was not significant after adjustment for predictors of colectomy (P = 0.06). There was a higher risk of colectomy in men (HR 1.44, 95% CI: 1.19-1.73), those diagnosed at an early age (HR 1.35, 95% CI: 1.04-1.75; 16-24 vs. 25-64) and early steroid users (HR 1.94, 95% CI: 1.59-2.37). 5-ASA users were less likely to require a colectomy (HR 0.35, 95% CI: 0.28-0.44). Amongst thiopurine users, those treated for greater than 12 months had a 71% reduction in risk of colectomy (HR 0.29, 95% CI: 0.21-0.40). Early thiopurines offered no additional benefit.

CONCLUSIONS

Thiopurine exposure for greater than 12 months reduces the likelihood of colectomy by 71%. Young men and those requiring steroids within 3 months of diagnosis are at greatest risk of colectomy, and most likely to benefit from sustained thiopurine use.

The impact of thiopurines on surgical outcomes in inflammatory bowel disease: do they make a difference?

Ulcerative colitis and Crohn's disease together are known as inflammatory bowel disease (IBD). Surgery is considered for more severe disease and is a dreaded consequence for patients. Thiopurines have proven efficacy in the induction and maintenance of remission of IBD, but the long-term need for surgery remains uncertain with conflicting results from the available studies. The timing and duration of thiopurines also appears to play a pivotal role in the management of these conditions and may also affect the need for surgery. Data from Denmark, Canada, Hungary and the UK appear to suggest a reduction in surgery rates prior to the introduction of anti-tumor necrosis factor (TNF) therapy. The authors aim to review the more recent literature evaluating the surgery rates in IBD and changes in disease trends over time. We ask whether increasing thiopurine prescribing has had an effect on the surgery rates in the era of biologic therapy and whether more aggressive treatment approaches have altered the natural history of IBD.

Factors associated with vitamin D deficiency in a multicultural inflammatory bowel disease cohort

OBJECTIVE

The aim of this study was to determine the prevalence of vitamin D deficiency in a multicultural inflammatory bowel disease (IBD) cohort and determine predictors of deficiency including ethnicity.

DESIGN

Patients with IBD were recruited into a dedicated database over a 6-month period and evaluated retrospectively.

SETTING

Department of Gastroenterology, St George's University Hospital, London, UK.

OUTCOMES MEASURED

Clinical data including demographics, ethnic group, disease phenotype by the Montreal classification, vitamin D level and season tested were recorded from clinical and electronic medical records. Vitamin D levels were classified as normal (≥50 nmol/l) and deficient (<50 nmol/l).

RESULTS

168 patients had a vitamin D level measured subsequent to diagnosis. There was no significant difference in the median vitamin D level between patients with Crohn's disease (CD) and ulcerative colitis (UC) (39 nmol/l (IQR 23-56) vs 28 nmol/l (IQR 17-51), p=0.35). Overall the median vitamin D level was significantly lower in non-Caucasians (Asian and Black) versus Caucasians (28 nmol/l (IQR 17-41) vs 41 nmol/l (IQR 25-63), p<0.0001). Multiple regression analysis revealed IBD related surgery (OR 2.9) and ethnicity (OR 6.0 non-Caucasian vs Caucasian) in CD and ethnicity (OR 5.0 non-Caucasian vs Caucasian) in UC were independently associated with vitamin D deficiency.

CONCLUSIONS

Vitamin D deficiency is common in IBD patients; therefore, we suggest monitoring of vitamin D levels and correction with supplements especially in non-Caucasians and those with a history of IBD related surgery.