反相高效液相色谱法测定利福昔明的含量

目的:采用反相高效液相色谱法测定利福昔明的含量。方法:色谱柱为C_(18)柱,流动相为甲醇—0.075mol·L~(-1)KH_2PO_4溶液-1.0mol·L~(-1)枸橼酸溶液(75:26:4),检测波长为254nm;流速为1.0mL·min~(-1)。结果:线性范围:10.0～100.0μg·mL~(-1),r=0.9999,回收率99.2％。供试品溶液在8h内稳定性良好,日内重复性RSD=0.24％,日间重复性RSD=0.50％。结论:本方法简单、快速,结果准确。     

Long-term treatment with mesalazine and rifaximin versus rifaximin alone for patients with recurrent attacks of acute diverticulitis of colon

BACKGROUND/AIMS: To compare efficacy of combined therapy with rifaximin and mesalazine versus rifaximin alone in treatment of patients with recurrent diverticulitis in order to evaluate: 1) rapidity in improvement of symptoms, 2) regulation of bowel attacks, 3) prevention of recurrence of diverticulitis. METHODS: A total of 218 consecutive eligible patients (131 males, 87 females age 64.3 years, range 51-79), affected by diverticulitis were monitored. Of these, 109 patients were treated with rifaximin 400 mg bid plus mesalazine 800 mg tid for 7 days, followed by rifaximin 400 mg bid plus mesalazine 800 mg bid for 7 days/month (group A); 109 patients were treated with rifaximin 400 mg bid for 7 days, followed by rifaximin 400 mg bid for 7 days/month (group B). Colonoscopy was performed after 3, 6 and 12 months of therapy. RESULTS: At end of follow-up, 193 patients were fully compliant to therapy Two patients died during study (1 in group A, 1 in group B), while four patients were lost to follow-up [1 in group A (0.91%) and 3 in group B (2.75%)]. The only side-effects recorded were transient urticaria (1 in group B, 0.91%) and epigastric pain (9 in group A, 8.25%). Severity of symptoms improved significantly in group A vs group B within 3 months (p < 0.005, p < 0.001 and p < 0.0001 and p < 0.0005 at 3, 6, 9 and 12 months, respectively). Bowel habits inproved significantly in group A vs group B within 3 months (p < 0.005, p < 0.0005, p < 0.001 and p < 0.0001 at 3,6,9 and 12 months respectively). Symptomatic recurrence of diverticulitis occurred in 3 patients in group A, while 13 patients showed recurrence of diverticulitis in group B (p < 0.005) during follow-up. CONCLUSIONS: This study clearly shows that rifaximin plus mesalazine are more effective than rifaximin alone in resolution of symptoms and prevention of recurrence of diverticulitis.     

Existing and emerging therapies for irritable bowel syndrome

Introduction: Irritable bowel syndrome is a common disorder that is associated with a significant impact on both affected individuals and society. While the pathophysiology of irritable bowel syndrome remains unknown, knowledge regarding the normal and abnormal functions of the gut and its complex interaction with the body's nervous systems continues to shed light on the multifactorial origins of irritable bowel syndrome symptoms. This article provides an overview of the current knowledge of the therapeutic approaches to irritable bowel syndrome.

Areas covered: A search of the online bibliographic databases MEDLINE and EMBASE was performed in order to identify all relevant articles published between 1980 and 2010. The search was enhanced with the use of a medical librarian. Bibliographies from potentially relevant articles were manually searched.

Expert opinion: The therapeutic options for irritable bowel syndrome are rapidly evolving beyond traditional symptom-based therapies, such as fiber, antispasmodics, antidiarrheals and laxatives, and are moving toward agents with organ-specific receptor selectivity directed, in many cases, at specific gastrointestinal functions.     

利福昔明胶囊对急性感染性腹泻的疗效和安全性及其血药浓度测定

目的评价利福昔明胶囊（抗结核病药）治疗急性感染性腹泻的疗效、安全性及口服后吸收情况。方法用随机对照前瞻性试验方法，共入选病例70例，利福昔明胶囊（试验组33例）每次200mg，每6h1次；左氧氟沙星胶囊（对照组35例）每次200mg，每12h1次，疗程均3天。试验组有10例患者接受了血药浓度分析。结果从开始服药至最后1次排不成型便的时间，试验组和对照组平均分别为33．56，31．13h，2组相比无明显差异（P〉0．05）；2者的临床疗效比较也无明显差异（P〉0．05）；利福昔明口服后血药浓度极低或测不出。结论利福昔明口服后基本不吸收，是治疗急性感染性腹泻的安全有效药物。     

The role of antimicrobials in Crohn’s disease

This review summarizes literature regarding the role of antimicrobials for induction and maintenance of Crohn’s disease (CD) remission. PubMed was searched (1966 to October 2012) for controlled trials involving adults and written in English. Five of the 13 identified studies showed benefit with the use of ciprofloxacin, metronidazole and rifaximin for induction of remission. Eight studies showed no benefit using ciprofloxacin, metronidazole, combination of metronidazole and ciprofloxacin or clarithromycin and rifaximin. Four of the five studies showed benefit based on colonic location. Perianal CD with draining fistulas responded in one of two studies. Two studies in postileocolonic resection demonstrated benefit of metronidazole or ornidazole in reducing CD recurrence. Antimicrobials, especially metronidazole, are promising for inducing remission in patients with colonic CD and preventing recurrence in postileocolonic resection.     

Rifaximin: a nonsystemic rifamycin antibiotic for gastrointestinal infections

Use of nonsystemic antimicrobials with activity against enteropathogens is a promising approach for treatment of infectious diarrhea and other nonsystemic gastrointestinal infections. Rifaximin is approved by the US FDA for the treatment of travelers’ diarrhea caused by noninvasive strains of Escherichia coli in patients aged 12 years and older, and for the reduction in risk of overt hepatic encephalopathy (HE) recurrence in patients aged 18 years or older. Rifaximin has been available in Italy since 1987 and overall is approved in 33 countries for various conditions, such as acute and chronic infections, bacterial diarrhea, HE, and pre- and postsurgical prophylaxis. There is accumulating evidence on the benefit of rifaximin for nonsystemic gastrointestinal infections. This article will serve as an update on rifaximin. The pharmacology and pharmacodynamics of rifaximin along with an updated review on the bacterial susceptibility to rifaximin will be presented. Finally, clinical trials with rifaximin for nonsystemic gastrointestinal indications will be updated.     

Rifaximin: a nonabsorbable rifamycin antibiotic for use in nonsystemic gastrointestinal infections

Rifaximin is a poorly water-soluble and minimally absorbed (<0.4%) rifamycin with in vitro activity against enteric Gram-negative bacteria including enteric pathogens. Fecal levels of the drug after 3 days’ oral therapy exceed 8000 µg/g. Rifaximin is effective in the treatment and prevention of travelers’ diarrhea due to Escherichia coli-predominant bacterial pathogens. It shows lower activity against dysenteric forms of bacterial diarrhea. The drug may be useful in other enteric infectious diseases, including Clostridium difficile colitis, pediatric bacterial diarrhea and Helicobacter pylori gastritis and chronic gastrointestinal disorders including hepatic encephalopathy, small bowel bacterial overgrowth, inflammatory-bowel disease, irritable-bowel syndrome and pouchitis. Importantly, rifaximin does not appear to lead to bacterial resistance. Rifaximin has an excellent safety profile and adverse drug reactions have been comparable to those associated with the placebo control agent.