Implications of direct amplification for measuring antimicrobial resistance using point-of-care devices.

Antimicrobial resistance (AMR) is recognized as a global threat to human health. Rapid detection and characterization of AMR is a critical component of most antibiotic stewardship programs. Methods based on amplification of nucleic acids for detection of AMR are generally faster than culture-based approaches but they still require several hours to more than a day due to the need for transporting the sample to a centralized laboratory, processing of sample, and sometimes DNA purification and concentration. Nucleic acids-based point-of-care (POC) devices are capable of rapidly diagnosing antibiotic-resistant infections which may help in making timely and correct treatment decisions. However, for most POC platforms, sample processing for nucleic acids extraction and purification is also generally required prior to amplification. Direct amplification, an emerging possibility for a number of polymerases, has the potential to eliminate these steps without significantly impacting diagnostic performance. This review summarizes direct amplification methods and their implication for rapid measurement of AMR. Future research directions that may further strengthen the possibility of integrating direct amplification methods with POC devices are also summarized.

Influence of Access, Anticoagulant, and Bleeding Definition on Outcomes of Primary Percutaneous Coronary Intervention: Early Experience of an US Academic Center.

Background We aimed to carry out comparison of different bleeding avoidance strategies in doing primary percutaneous coronary intervention (PPCI) using either radial or femoral as access of choice and either bivalirudin or unfractionated heparin as anticoagulant of choice. In this analysis, we analyzed the influence of major bleeding definition on bleeding outcomes as well. Methods We did a retrospective analysis of 139 patients with ST-segment elevation myocardial infarction (STEMI) who had PPCI in our academic center from January 2010 till October 2013. The primary outcome at 30 days was a composite of death from any cause or stent thrombosis or non-coronary artery bypass grafting (CABG) related major bleeding (CathPCI Registry definition) and secondary outcomes were individual components of primary outcome and the hospital length of stay. Results There was no significant difference among different access/anticoagulant combinations with regards to primary outcome (22% in radial/bivalirudin vs. 5% in radial/heparin vs. 17% in femoral/bivalirudin vs. 28% in femoral/heparin group; p = 0.2) as well as its individual components except the hospital length of stay (2.56 vs. 3 vs. 3.97 vs. 4.4 days each; p < 0.0001). The overall rate of major bleeding was 11.5%. When we use HORIZON-AMI bleeding definition, it went up to 25 % due to one particular component (p < 0.004). Conclusions This single center observational study doing PPCI did not show any superiority of one bleeding avoidance strategy over others with regard to primary outcome and its individual components except the hospital length of stay. It also shows the importance of bleeding definition on bleeding outcomes.