Impact of environmental and dietary factors on the course of inflammatory bowel disease

Besides their possible effects on the development of inflammatory bowel disease(IBD),some environmental factors can modulate the clinical course of both ulcerative colitis(UC) and Crohn's disease(CD).This review is mainly devoted to describing the current knowledge of the impact of some of these factors on the outcome of IBD,with special emphasis on smoking and diet.Although the impact of smoking on the susceptibility to develop CD and UC is firmly established,its influence on the clinical course of both diseases is still debatable.In CD,active smoking is a risk factor for postoperative recurrence.Beyond this clinical setting,smoking cessation seems to be advantageous in those CD patients who were smokers at disease diagnosis,while smoking resumption may be of benefit in ex-smokers with resistant UC.The role of dietary habits on the development of IBD is far from being well established.Also,food intolerances are very frequent,but usually inconsistent among IBD patients,and therefore no general dietary recommendations can be made in these patients.In general,IBD patients should eat a diet as varied as possible.Regarding the possible therapeutic role of some dietary components in IBD,lessons should be drawn from the investigation of the primary therapeutic effect of enteral nutrition in CD.Low-fat diets seem to be particularly useful.Also,some lipid sources,such as olive oil,medium-chain triglycerides,and perhaps omega-3 fatty acids,might have a therapeutic effect.Fermentable fiber may have a role in preventing relapses in inactive UC.

Characterization and validation of a chronic retinal neovascularization rabbit model by evaluating the efficacy of anti-angiogenic and anti-inflammatory drugs

AIM:To establish a rabbit model with chronic condition of retinal neovascularization(RNV)induced by intravitreal(IVT)injection of DL-2-aminoadipic acid(DL-AAA),a retinal glial(Mül er)cell toxin,extensive characterization of DL-AAA induced angiographic features and the suitability of the model to evaluate anti-angiogenic and anti-inflammatory therapies for ocular vascular diseases.METHODS:DL-AAA(80 mmol/L)was administered IVT into both eyes of Dutch Belted rabbit.Post DL-AAA delivery,clinical ophthalmic examinations were performed weekly following modified Mc Donald-Shadduck Scoring System.Color fundus photography,fluorescein angiography(FA),and optical coherence tomography(OCT)procedures were performed every 2 or 4 wk until stable retinal vascular leakage was observed.Once stable retinal leakage(12 wk post DL-AAA administration)was established,anti-vascular endothelial growth factor(VEGF)(bevacizumab,ranibizumab and aflibercept)and anti-inflammatory(triamcinolone,TAA)drugs were tested for their efficacy after IVT administration.Fluorescein angiograms were scored before and after treatment following a novel grading system,developed for the DL-AAA rabbit model.RESULTS:Post DL-AAA administration,eyes were presented with moderate to severe retinal/choroidal inflammation which was accompanied by intense vitreous flare and presence of inflammatory cells in the vitreous humor.Retinal hemorrhage was restricted to the tips of neo-retinal vessels.FA revealed maximum retinal vascular leakage at 2 wk after DL-AAA injection and then persisted as evidenced by stable mean FA scores in weeks 8 and 12.Retinal vascular angiographic and tomographic features were stable and consistent up to 36 mo among two different staggers induced for RNV at two different occasions.Day 7,mean FA scores showed that 1μg/eye of bevacizumab,ranibizumab,aflibercept and 2μg/eye of TAA suppress 65%,90%,100%and 50%retinal vascular leakage,respectively.Day 30,bevacizumab and TAA continued to show 66%and 44%suppression while ranibizumab effect was becoming less effective(68%).In contrast,aflibercept was still able to fully(100%)suppress vascular leakage on day 30.On day 60,bevacizumab,ranibizumab and TAA showed suppression of 7%,12%,and 9%retinal vascular leakage,respectively,however,aflibercept continued to be more effective showing 50%suppression of vascular leakage.CONCLUSION:The DL-AAA rabbit model mimics RNV angiographic features like RNV and chronic retinal leakage.Based on these features the DL-AAA rabbit model provides an invaluable tool that could be used to test the therapeutic efficacy and duration of action of novel anti-angiogenic formulations,alone or in combination with anti-inflammatory compounds.

Surgery for Crohn's disease in the era of biologicals:A reduced need or delayed verdict?

Crohn's disease(CD) is a chronic inflammatory bowel disease that can affect the entire gastrointestinal tract.Ultimately,up to 70% of all patients will need surgery,despite optimized medical therapy.Moreover,about half of the patients will need redo-surgery because of disease recurrence.The introduction of anti-tumor necrosis factor(TNF) drugs(Infliximab in 1998) revolutionized the treatment of CD.Different randomized trials assessed the efficacy of anti-TNF treatment not only to induce,but also to maintain,steroid-free remission.Furthermore,these agents can rapidly lead to mucosal healing.This aspect is important,as it is a major predictor for long-term disease control.Subgroup analyses of responding patients seemed to suggest a reduction in the need for surgery at median-term follow up(1-3 years).However if one looks at population surveys,one does not observe any decline in the need for surgery since the introduction of Infliximab in 1998.The short follow-up term and the exclusion of patients with imminent surgical need in the randomized trials could bias the results.Only 60% of patients respond to induction of anti-TNF therapy,moreover,some patients will actually develop resistance to biologicals.Many patients are diagnosed when stenosing disease has already occurred,obviating the need for biological therapy.In a further attempt to change the actual course of the disease,top down strategies have been progressively implemented.Whether this will indeed obviate surgery for a substantial group of patients remains unclear.For the time being,surgery will still play a pivotal role in the treatment of CD.

Improvement of lenvatinib-induced nephrotic syndrome after adaptation to sorafenib in thyroid cancer:A case report

BACKGROUND Target therapy is licensed by United States Food and Drug Administration on certain cancers.Both sorafenib and lenvatinib are tyrosine kinase inhibitor and indicated on radioactive iodine(RAI)-refractory differentiated thyroid cancer(DTC).Lenvatinib is more effective in cancers'control than sorafenib,but causes more nephrotoxicity than sorafenib does.This case is the second published case about the serial adaptions from lenvatinib to sorafenib for improving the proteinuria and,meanwhile,achieving the therapeutic goal.CASE SUMMARY A 56-year-old man suffered from bilateral edematous lower extremities after 1-mo prescription of lenvatinib of 20 mg/d for RAI-refractory DTC.Aside from this symptom,he also developed hypertension.His laboratory showed grade-3 proteinuria(estimated 24-h urine protein:9993 mg),hypoalbuminemia and hypercholesterolemia.Anti-vascular endothelial growth factor(VEGF)therapyinduced nephrotic syndrome was impressed.After reduced dosage of lenvatinib of 10 mg/d and related symptomatic drugs,limited improvement was observed in both adverse effects and caner control.Under this condition,we substituted sorafenib of 400 mg/d for lenvatinib of 10 mg/d.After a 5-mo prescription,not only hypertension and peripheral edema were greatly improved,but also proteinuria was improved from grade three to grade one(estimated 24-h urine protein:962 mg).At the same time the cancer control was achieved,judged from computed tomography and laboratory evidence[thyroglobulin(Tg)before prescription of sorafenib:354.7 ng/m L;Tg after prescription of sorafenib:108.9 ng/m L].CONCLUSION Adaption from lenvatinib to sorafenib is a feasible method to improve the antiVEGF therapy-induced nephrotic syndrome and achieve the therapeutic goal at the same time.