Optimization of biologic therapy in Crohn’s disease

Optimizing biologic therapy in inflammatory bowel disease: a Delphi consensus in the United Arab Emirates

BACKGROUND

Inflammatory bowel diseases (IBD) are chronic, relapsing-remitting inflammatory conditions with a substantial negative impact on health-related quality of life and work productivity. Treatment of IBD has been revolutionized by the advent of biologic therapies, initially with anti-TNF agents and more recently with multiple alternatives targets, and yet more under development.

OBJECTIVES

Approximatively one third of patients do not respond to biologic therapy and more importantly a significant proportion experiences partial response or loss of response during treatment. The latter are common clinical situations and paradoxically are not addressed in the commercial drug labels and available guidelines. There is therefore a clinical need for physicians to understand when and how eventually to optimize the biologic therapy.

DESIGN

This consensus using a Delphi methodology was promoted and supported by the Emirates Society of Gastroenterology and Hepatology to close this gap.

DATA SOURCES AND METHODS

Following an extensive systematic review of over 60,000 studies, 81 studies with dose escalation and five addressing drug monitoring were selected and in addition five systematic reviews and three guidelines.

RESULTS AND CONCLUSION

after three rounds of voting 18 statements were selected with agreement ranging from of 80% to 100.

Clinical Criteria Can Identify Children With Osteopenia in Newly Diagnosed Crohn Disease

OBJECTIVES

Chronic inflammation of Crohn disease (CD) is associated with reduced bone mineral density (BMD). As bone mass is almost exclusively accrued during childhood, early recognition of osteopenia is especially important in pediatric CD. We aimed to identify variables associated with osteopenia to guide dual-energy X-ray absorptiometry (DXA) scan screening to those who most need it.

METHODS

This was a retrospective inception cohort study of children newly diagnosed with CD, and routinely referred to DXA scans. Demographic and explicit clinical data were recorded along with whole-body less head BMD, adjusted for age, sex, and height by z-scores.

RESULTS

Of the 116 included children (mean age 13 ± 3.1 years, 67 [58%] boys, mean body mass index [BMI] 16.7 ± 2.6), 63 (54%) had normal BMD (z-score > -1) or borderline osteopenia (-1 ≥ z-score > -2) and 53 (46%) had osteopenia (z-score ≤ -2). Osteopenia was associated with lower BMI z-score (-0.8 ± 1.2 vs -1.8 ± 1.1, P < 0.001) and higher PCDAI (33.7 ± 15.2 vs 25.7 ± 16.5; P = 0.009) than those with BMD z-score >-2. In total, 59% of children with BMI z-score <-0.5 had moderate-severe osteopenia and only 18% of those with higher z-scores. Multivariate logistic regression identified BMI z-score as the sole risk factor (OR 1.28 [95% CI 1.08-1.52], P = 0.005). BMI z-score ≥-0.5 excludes osteopenia with a sensitivity 87%, specificity 49%, NPV 82%, and PPV 59%.

CONCLUSIONS

Osteopenia was found in nearly half of children with newly onset CD. BMI z-score <-0.5 should prompt referral to DXA screening.

Targeting desmosomal adhesion and signalling for intestinal barrier stabilization in inflammatory bowel diseases-Lessons from experimental models and patients

Inflammatory bowel diseases (IBD) such as Crohn's disease (CD) and Ulcerative colitis (UC) have a complex and multifactorial pathogenesis which is incompletely understood. A typical feature closely associated with clinical symptoms is impaired intestinal epithelial barrier function. Mounting evidence suggests that desmosomes, which together with tight junctions (TJ) and adherens junctions (AJ) form the intestinal epithelial barrier, play a distinct role in IBD pathogenesis. This is based on the finding that desmoglein (Dsg) 2, a cadherin-type adhesion molecule of desmosomes, is required for maintenance of intestinal barrier properties both in vitro and in vivo, presumably via Dsg2-mediated regulation of TJ. Mice deficient for intestinal Dsg2 show increased basal permeability and are highly susceptible to experimental colitis. In several cohorts of IBD patients, intestinal protein levels of Dsg2 are reduced and desmosome ultrastructure is altered suggesting that Dsg2 is involved in IBD pathogenesis. In addition to its adhesive function, Dsg2 contributes to enterocyte cohesion and intestinal barrier function. Dsg2 is also involved in enterocyte proliferation, barrier differentiation and induction of apoptosis, in part by regulation of p38MAPK and EGFR signalling. In IBD, the function of Dsg2 appears to be compromised via p38MAPK activation, which is a critical pathway for regulation of desmosomes and is associated with keratin phosphorylation in IBD patients. In this review, the current findings on the role of Dsg2 as a novel promising target to prevent loss of intestinal barrier function in IBD patients are discussed.