Fecal microbiota transplantation (FMT) is a method to directly change the recipient's gut microbiota to normalize the composition and gain a therapeutic benefit. The history of FMT has been traced back to the 4th century and has been highly regarded since 2013, when the United States Food and Drug Administration approved FMT for treating recurrent and refractory Clostridium difficile infection. Since then, the range of FMT applications extended rapidly and broadly not only in gastrointestinal disorders, but also in extra-gastrointestinal diseases. Donor selection with questionnaire, interview, blood tests, and stool examinations should be strictly performed before FMT to reduce and prevent occurrence of any adverse events. Step-by-step cautious fecal and recipient preparation along with adequately choosing delivery methods based on individual clinical situations are key points of the FMT process. Although current evidence deems FMT as a generally safe therapeutic method with few adverse effects, the long-term outcomes of FMT have not been completely elucidated. Therefore, establishing periodicity and length of regular follow-up after FMT to monitor the clinical efficacy and long-term adverse events are other essential issues. In the future, we will look forward to personalized FMT for different patients and conditions according to varied hosts and diseases.

Accurate diagnosis of Helicobacter pylori (H. pylori) infection is a crucial part in the effective management of many gastroduodenal diseases. Several invasive and non-invasive diagnostic tests are available for the detection of H. pylori and each test has its usefulness and limitations in different clinical situations. Although none can be considered as a single gold standard in clinical practice, several techniques have been developed to give the more reliable results. Invasive tests are performed via endoscopic biopsy specimens and these tests include histology, culture, rapid urease test as well as molecular methods. Developments of endoscopic equipment also contribute to the real-time diagnosis of H. pylori during endoscopy. Urea breathing test and stool antigen test are most widely used non-invasive tests, whereas serology is useful in screening and epidemiological studies. Molecular methods have been used in variable specimens other than gastric mucosa. More than detection of H. pylori infection, several tests are introduced into the evaluation of virulence factors and antibiotic sensitivity of H. pylori, as well as screening precancerous lesions and gastric cancer. The aim of this article is to review the current options and novel developments of diagnostic tests and their applications in different clinical conditions or for specific purposes.

This prospective study was designed to determine the efficacy of a levofloxacin-based rescue therapy for Helicobacter pylori infection after failure of standard triple therapies. We also surveyed the predictors of this rescue therapy. From June 2005 to March 2007, 1036 patients infected with H. pylori received standard triple regimens (proton pump inhibitor, clarithromycin and amoxicillin). H. pylori eradication was achieved in 855 (82.5%) subjects. One hundred and sixty-six eradication-failure patients were enrolled and randomly assigned to receive a 7 day eradication therapy with esomeprazole, bismuth subcitrate, tetracycline and metronidazole (EBTM) or esomeprazole, amoxicillin and levofloxacin (EAL). Follow-up endoscopy was done 16 weeks later to assess the treatment response. Patients' response, CYP2C19 genotypes and antibiotic resistances were also examined. Intention-to-treat analysis revealed that both groups showed similar eradication rates [EBTM 63.9%; 95% confidence interval (CI): 53.6–74.2 and EAL 69.9%; 95% CI: 60.1–79.7] (P = 0.89). Per-protocol results were EBTM = 84.1% (95% CI: 75.1–93.1) and EAL = 75.3% (95% CI: 65.8–84.8) (P = 0.82). Both regimens had similar compliance (P = 0.32), but the EBTM group had more adverse events (P = 0.27). Logistic regression analysis showed that poor compliance, CYP2C19 homozygous extensive metabolizer genotype and levofloxacin resistance were important predictors for eradication failure. The EAL regimen can achieve an efficacy similar to that of the standard EBTM therapy. It may be very useful in countries where bismuth salts are not available. Compliance, CYP2C19 genotype and resistances to antibiotics may influence the outcome of levofloxacin-based rescue therapy. It seems advisable to reserve levofloxacin for rescue treatment to avoid an increase in the resistance phenomenon.

Over-expression of AURKA , SKA3 and DSN1 contributes to colorectal adenoma to carcinoma progression