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Objectives: To determine the prevalence of 16S rRNA methyltransferase- (16S RMTase-) producing Gram-negative bacteria in patients in the UK and to identify potential risk factors for their acquisition., Methods: A 6 month prospective surveillance study was conducted from 1 May to 31 October 2016, wherein 14 hospital laboratories submitted Acinetobacter baumannii, Enterobacterales and Pseudomonas aeruginosa isolates that displayed high-level amikacin resistance according to their testing methods, e.g. no zone of inhibition with amikacin discs. Isolates were linked to patient travel history, medical care abroad, and previous antibiotic exposure using a surveillance questionnaire. In the reference laboratory, isolates confirmed to grow on Mueller-Hinton agar supplemented with 256 mg/L amikacin were screened by PCR for 16S RMTase genes armA, rmtA-rmtH and npmA, and carbapenemase genes (blaKPC, blaNDM, blaOXA-48-like and blaVIM). STs and total antibiotic resistance gene complement were determined via WGS. Prevalence was determined using denominators for each bacterial species provided by participating hospital laboratories., Results: Eighty-four isolates (44.7%), among 188 submitted isolates, exhibited high-level amikacin resistance (MIC >256 mg/L), and 79 (94.0%) of these harboured 16S RMTase genes. armA (54.4%, 43/79) was the most common, followed by rmtB (17.7%, 14/79), rmtF (13.9%, 11/79), rmtC (12.7%, 10/79) and armA + rmtF (1.3%, 1/79). The overall period prevalence of 16S RMTase-producing Gram-negative bacteria was 0.1% (79/71 063). Potential risk factors identified through multivariate statistical analysis included being male and polymyxin use., Conclusions: The UK prevalence of 16S RMTase-producing Gram-negative bacteria is low, but continued surveillance is needed to monitor their spread and inform intervention strategies., (© Crown copyright 2021.)

Nontuberculous mycobacteria (NTM) are an important cause of pulmonary disease in patients with cystic fibrosis (CF). A new culture medium (RGM medium) for the isolation of rapidly growing mycobacteria from the sputum of cystic fibrosis patients has recently been reported. The aim of this study was to compare culture of sputum samples on RGM medium with culture using a standard automated liquid culture method. Sputum samples were obtained from 187 distinct patients with CF attending King's College Hospital, London, United Kingdom. Each sample was decontaminated with 3% oxalic acid and inoculated into a mycobacterial growth indicator tube (MGIT) that was monitored for 42 days using the Bactec MGIT 960 instrument. Each sample was also cultured, without decontamination, onto RGM medium, which was incubated for 10 days at 30°C. Mycobacteria were isolated from 28 patients (prevalence, 15%). Mycobacteria were detected in 24 samples (86%) using the MGIT and in 23 samples (82%) using RGM medium (P = 1.00). In this setting, RGM medium showed sensitivity equivalent to that of the MGIT for isolation of NTM from the sputum of patients with CF. RGM medium offers a simple, convenient tool that can be embedded into routine culture methods, allowing the culture of all sputum samples that are submitted from patients with CF., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

In the last two decades there have been dramatic changes in the epidemiology of Clostridium difficile infection (CDI), with increases in incidence and severity of disease in many countries worldwide. The incidence of CDI has also increased in surgical patients. Optimization of management of C difficile, has therefore become increasingly urgent. An international multidisciplinary panel of experts prepared evidenced-based World Society of Emergency Surgery (WSES) guidelines for management of CDI in surgical patients.

Purpose: This study aims to investigate what factors predict the development of postoperative bloodstream infection (BSI) in patients transplanted electively for chronic liver disease and compare outcomes in infected transplant recipients (BCLD) with noninfected patients (CLD)., Methods: A retrospective cohort study of 218 patients who had elective liver transplantation (LT) between January 2003 and July 2005 and admitted to a specialist intensive care unit (ICU) was done., Results: Fifteen patients had BSI post-LT (BCLD, 29 isolates) while in the ICU, and 203 patients did not (CLD). Thirty-eight percent of isolates were gram negatives; 55%, gram positives; and 7%, fungemia. Median time to first BSI post-LT was 11 days (range, 3-16 days). On admission post-LT to the ICU, patients with BCLD had higher Acute Physiology and Chronic Health Evaluation II scores (23 vs 10, P < .001). While in the ICU, patients with BCLD had greater requirements for renal replacement therapy (73% vs 8%) and days on mechanical ventilation (17 vs 2 days) and longer median ICU stay (21 vs 3 days, P < .001 for all). One-year survival was worse in the BCLD group (40% vs 94%, P < .001). On multivariate analysis, Acute Physiology and Chronic Health Evaluation II score (odds ratio, 1.36) post-LT was independently associated with subsequent BSI. Bloodstream infection (hazards ratio, 8.7) was independently associated with mortality., Conclusion: Bloodstream infection post-LT was associated with increased severity of illness on admission, greater requirements for organ support, and increased mortality., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Purpose: To determine what physiological and biochemical factors predict development of bacteraemia and mortality in patients with acute liver failure (ALF)., Methods: Retrospective analysis of 206 ALF patients admitted to a specialist liver intensive therapy unit (LITU) from January 2003 to July 2005 (data collected prospectively)., Results: A total of 206 patients were defined with ALF: 72 (35%) suffered bacteraemia (BAClf) and 134 (65%) did not (NBAClf). Gram positive organisms were observed in 44% of isolates, gram negatives in 52% and fungaemia in 4%. Median time to first bacteraemia was 10 (7-16) days. On admission, BAClf patients had higher SIRS scores and degrees of hepatic encephalopathy (HE). During their LITU course, BAClf patients had significantly increased requirements for renal replacement therapy (RRT), mechanical ventilation, and longer median LITU stay. Multivariate analysis (logistical regression) demonstrated significant predictors of bacteraemia on admission were HE grade >2 (Odds Ratio 1.6) and SIRS score >1 (OR 2.7). In all patients, independent predictors of mortality (logistical) were age (OR 1.41), maximum HE grade pre-intubation (1.76), Lactate (1.14) and Acute Physiology and Chronic Health Evaluation II score (APACHEII) (1.09), but not bacteraemia. Transplantation was protective (OR 0.20)., Conclusion: In this study, severity of hepatic encephalopathy and SIRS score >1 were predictive of bacteraemia. APACHEII was independently predictive of mortality in all ALF patients but not bacteraemia.