An in vitro analysis of microbial transmission during EUS-guided FNA and the utility of sterilization agents

Antibioprophylaxis in endoscopic ultrasound guided fine needle aspiration in pancreatic cysts: A systematic review and meta-analysis

Antibioprohylaxis (ABP) for pancreatic cystic lesion is still a debated clinical indication. Although professional societies guidelines still recommend ABP in endoscopic ultrasound-fine needle aspiration (EUS-FNA) for pancreatic cystic lesions (PCL), this standard of care recommendation was based on old and weakly planned studies with a small number of patients. Herein, in this work, we provide a critical review with pooled data analysis of the available literature. Overall, the studies reported are weak and limited with small number of patients, the absence of exact definition of infection and the heterogenicity of the type and the duration of the ABP used. Pooled data analysis showed that the effect of ABP on the rate of cyst infection was not significant (OR 0.56, 95% CI 0.17-1.2), with no significant heterogenicity between the results of the studies reviewed and reported (as assessed by Breslow Day test for homogeneity of OR's [P = 0.15]). The pooled infection rate without ABP was 0.89% and 0.36% in the ABP group. Moreover, according to the pooled data infection rate, sample size calculation demonstrated that 6954 patients are needed to show superiority of ABP, with a number needed to treat of 179 patients to prevent single infection. However, through the literature only six studies (1660 patients) reported the cyst infection rate among ABP versus control, making these results scarce and biased by a small number of patients. Therefore, we suggest the need to revise the guidelines, until performing well organized large international study to solve this controversy.

Diagnostic endoscopic ultrasonography: Assessment of safety and prevention of complications

Endoscopic ultrasonography (EUS) has gained wide acceptance as an important, minimally invasive diagnostic tool in gastroenterology, pulmonology, visceral surgery and oncology. This review focuses on data regarding risks and complications of non-interventional diagnostic EUS and EUS-guided fine-needle biopsy (EUS-FNB). Measures to improve the safety of EUS und EUS-FNB will be discussed. Due to the specific mechanical properties of echoendoscopes in EUS, there is a low but noteworthy risk of perforation. To minimize this risk, endoscopists should be familiar with the specific features of their equipment and their patients’ specific anatomical situations (e.g., tumor stenosis, diverticula). Most diagnostic EUS complications occur during EUS-FNB. Pain, acute pancreatitis, infection and bleeding are the primary adverse effects, occurring in 1% to 2% of patients. Only a few cases of needle tract seeding and peritoneal dissemination have been reported. The mortality associated with EUS and EUS-FNB is 0.02%. The risks associated with EUS-FNB are affected by endoscopist experience and target lesion. EUS-FNB of cystic lesions is associated with an increased risk of infection and hemorrhage. Peri-interventional antibiotics are recommended to prevent cyst infection. Adequate education and training, as well consideration of contraindications, are essential to minimize the risks of EUS and EUS-FNB. Restricting EUS-FNB only to patients in whom the cytopathological results may be expected to change the course of management is the best way of reducing the number of complications.

An ex vivo bacteriologic study comparing antiseptic techniques for natural orifice translumenal endoscopic surgery (NOTES) via the gastrointestinal tract

BACKGROUND

NOTES via the gastrointestinal tract raises the specter of intra-peritoneal infection. Various anti-microbial techniques have been employed in animal and human survival studies, including saline lavage, intravenous and topical antibiotics, and povidone-iodine, although there is a paucity of data regarding their general effectiveness.

AIM

To assess the effectiveness of existing sterilization techniques for NOTES by quantifying and speciating colony-forming units (CFUs) before and after treatment.

DESIGN

Ex vivo animal studies; bacteriological study.

METHODS

Stomachs and distal colons were harvested en bloc from ten fasted adult white pigs following euthanasia. Half received cefazolin 1 g intravenously prior to killing. Multiple tissue samples were obtained from each resected organ. Each tissue sample was then assigned to one of five treatment arms: (1) normal saline, (2) Betadine, (3) cefazolin/metronidazole suspension, (4) chlorhexidine, (5) no treatment. Fifteen samples were used per arm. After treatment, the mucosal surface of each sample was swabbed and inoculated in normal saline, followed by serial dilutions, which were then plated onto sheep's blood agar plates and incubated under aerobic and anaerobic conditions. CFUs were quantified and speciated.

RESULTS

Median bacterial density was estimated to be 8.0 × 10(5) CFUs/ml (stomach) and 1.9 × 10(6) CFUs/ml (colon). The predominant organisms were Escherichia coli (stomach) and both E. coli and Enterococcus sp. (colon). Saline and antibiotic suspension lavages caused a 1-log reduction in stomach and colon. Betadine/chlorhexidine lavage resulted in a 4-log reduction. Intravenous antibiotics alone resulted in a 4-log reduction. Combining intravenous antibiotics and either Betadine or chlorhexidine decreased counts to the 10(1) level. By Kruskal-Wallis method, differences were statistically significant (p = 0.001).

CONCLUSIONS

The use of intravenous antibiotics in addition to topical Betadine or chlorhexidine effectively reduced microbial burden in both gastric and colonic mucosa in this porcine model to the 10(1) level.