Observational studies examining patient management in infectious diseases

Knowledge of Medical Imaging Professionals on Healthcare-Associated Infections: A Systematic Review and Meta-Analysis

Healthcare-associated infections (HCAIs) are a significant concern for both healthcare professionals and patients. With recent advances in imaging modalities, there is an increase in patients visiting the radiology department for diagnosis and therapeutic examination. The equipment used for the investigator is contaminated, which may result in HCAIs to the patients and healthcare professionals. Medical imaging professionals (MIPs) should have adequate knowledge to overcome the spread of infection in the radiology department. This systematic review aimed to examine the literature on the knowledge and precaution standard of MIPs on HCIAs. This study was performed with a relative keyword using PRISMA guidelines. The articles were retrieved from 2000 to 2022 using Scopus, PubMed, and ProQuest databases. The NICE public health guidance manual was used to assess the quality of the full-length article. The search yielded 262 articles, of which Scopus published 13 articles, PubMed published 179 articles, and ProQuest published 55 articles. In the present review, out of 262 articles, only 5 fulfilled the criteria that reported MIPs' knowledge of Jordan, Egypt, Sri Lanka, France, and Malawi populations. The present review reported that MIPs have moderate knowledge and precautionary standards regarding HCIAs in the radiology department. However, due to the limited studies published in the literature, the current review limits the application of the outcome in the vast MIPs population. This review recommended further studies to be conducted among the MIPs worldwide to know the actual knowledge and precaution standards regarding HCIAs.

The role of combination therapy in the treatment of severe infections caused by carbapenem resistant gram-negatives: a systematic review of clinical studies

BACKGROUND

Effective treatment of sepsis due to carbapenem-resistant Gram-negative bacteria (CR-GNB) remains a challenge for clinicians worldwide. In recent years, the combination of antibiotics has become the preferred treatment strategy for CR-GNB infection. However, robust evidence to support this approach is lacking. This systematic review aimed at critically evaluating all available antibiotic options for CR-GNB sepsis with particular focus on combination.

METHODS

We systematically searched published literature from January 1945 until December 2018 for observational comparative and non-comparative studies and randomized trials examining any antibiotic option for CR-GNB. Studies were included if reporting microbiologically-confirmed infection caused by Acinetobacter baumannii, Enterobacteriaceae/Klebsiella spp., or Pseudomonas aeruginosa, reporting at least one of the study outcomes, and definitive antibiotic treatment. Carbapenem-resistance was defined as phenotypically-detected in vitro resistance to at least one of the following carbapenems: doripenem, ertapenem, imipenem, meropenem. Each antibiotic regimen was classified as "defined" when at least the molecular class(es) composing the regimen was detailed. Primary outcomes were 30-day and attributable mortality. Bayesian network meta-analysis (NMA) approach was selected for quantitative synthesis to explore feasibility of pooling data on antibiotic regimens.

RESULTS

A total of 6306 records were retrieved and 134 studies including 11,546 patients were included: 54 studies were on Acinetobacter, 52 on Enterobacteriaceae/Klebsiella, 21 on mixed Gram-negative, and 7 on Pseudomonas. Nine (7%) were RCTs; 19 prospective cohorts (14%), 89 (66%) retrospective, and 17 (13%) case series. Forty-one studies (31%) were multicentric. Qualitative synthesis showed an heterogeneous and scattered reporting of key-clinical and microbiological variables across studies. Ninety-two distinct antibiotic regimens were identified with 47 of them (51%, 5863 patients) not reporting any details on numbers, type, dosage and in vitro activity of the included antibiotic molecules. The NMAs could not be performed for any of the selected outcome given the presence of too many disconnected components.

CONCLUSION

The existing evidence is insufficient to allowing for the formulation of any evidence-based therapeutic recommendation for CR-GNB sepsis. Future studies must provide a standardized definition of antibiotic regimen to drive recommendations for using combination of antibiotics that can be reliably applied to clinical practice.

The Impact of Carbapenem Resistance on Mortality in Patients With Klebsiella Pneumoniae Bloodstream Infection: An Individual Patient Data Meta-Analysis of 1952 Patients

INTRODUCTION

Available evidence from observational studies and meta-analyses has highlighted an increased mortality in patients with carbapenem-resistant Klebsiella pneumoniae (CRKP) bloodstream infections (BSI) compared with their carbapenem-susceptible (CSKP) counterparts, but the exact reasons for this outcome difference are still to be determined.

METHODS

We updated the search of a previous meta-analysis through four databases up to April 2018. A two-stage individual-patient data (IPD) meta-analysis was conducted, building an adjusting model to account for age, comorbidities and activity of empirical and targeted antimicrobial therapy. The protocol was registered on PROSPERO (identifier: CRD42018104256).

RESULTS

IPD data were obtained from 14 out of 28 eligible observational studies. A total of 1952 patients were investigated: 1093 in the CRKP group and 859 in the CSKP group. Patients with CRKP-BSI had a twofold risk of death compared with CSKP-infected patients [adjusted odds ratio (aOR) 2.17; 95% confidence interval (CI) 1.56-3.04; I² = 44.1%]. Mortality was higher in patients with CRKP BSI, in both the subgroup of absent/inactive (aOR 1.75; 95% CI 1.24-2.47; I² = 0) and of active initial therapy (aOR 2.66; 95% CI 1.70-4.16; I² = 16%) as well as in case of active targeted therapy (aOR 2.21; 95% CI 1.36-3.59; I² = 58%).

CONCLUSION

Resistance to carbapenem is associated with worse outcome in patients with BSI by Klebsiella pneumoniae even adjusting for comorbidities and treatment appropriateness according to in vitro activity of empirical and targeted therapy. This applies to a scenario dominated by colistin-based therapies for CRKP. Further studies are needed to compare the mortality difference between CRKP and CSKP cases in the light of new anti-CRKP antimicrobials.

A Systematic Review of Healthcare-Associated Infectious Organisms in Medical Radiation Science Departments

Healthcare-associated infections (HAIs) pose a significant occupational risk to medical radiation science (MRS) professionals, who have a high degree of patient contact. Current research largely focusses on HAIs in patients, with limited attention given to infectious organisms that MRS professionals are exposed to. This is a significant gap that this systematic review seeks to address by summarizing current literature to determine the infectious organisms within MRS departments, their reservoirs, and transmission modes. Reporting of this systematic review follows the preferred reporting items for systematic reviews and meta-analyses guidelines. Five databases were searched (Scopus, Medical Literature Analysis and Retrieval System Online (MEDLINE), the Cochrane Library, EMBASE, and Cumulative Index to Nursing and Allied Health Literature (CINAHL)) for relevant studies published between 1983 and 2018. Quality assessment was performed using checklists from the Johanna Briggs Institute. Nineteen studies were included in the review; twelve of which were set in diagnostic radiography departments, two in radiotherapy departments, and five in non-MRS departments. No studies were set in nuclear medicine departments, indicating a gap in the available literature. A total of 19 genera of infectious organisms were identified in the literature, with Staphylococcus, Escherichia, Bacillus, and Corynebacterium reported in all MRS departments. Infectious organisms were identified in all observational studies, indicating a need for better infection control methods and/or compliance training within MRS to minimize the risk of infections.

Use of nebulized antimicrobials for the treatment of respiratory infections in invasively mechanically ventilated adults: a position paper from the European Society of Clinical Microbiology and Infectious Diseases

With an established role in cystic fibrosis and bronchiectasis, nebulized antibiotics are increasingly being used to treat respiratory infections in critically ill invasively mechanically ventilated adult patients. Although there is limited evidence describing their efficacy and safety, in an era when there is a need for new strategies to enhance antibiotic effectiveness because of a shortage of new agents and increases in antibiotic resistance, the potential of nebulization of antibiotics to optimize therapy is considered of high interest, particularly in patients infected with multidrug-resistant pathogens. This Position Paper of the European Society of Clinical Microbiology and Infectious Diseases provides recommendations based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology regarding the use of nebulized antibiotics in invasively mechanically ventilated adults, based on a systematic review and meta-analysis of the existing literature (last search July 2016). Overall, the panel recommends avoiding the use of nebulized antibiotics in clinical practice, due to a weak level of evidence of their efficacy and the high potential for underestimated risks of adverse events (particularly, respiratory complications). Higher-quality evidence is urgently needed to inform clinical practice. Priorities of future research are detailed in the second part of the Position Paper as guidance for researchers in this field. In particular, the panel identified an urgent need for randomized clinical trials of nebulized antibiotic therapy as part of a substitution approach to treatment of pneumonia due to multidrug-resistant pathogens.

Polymyxin monotherapy or in combination against carbapenem-resistant bacteria: systematic review and meta-analysis

OBJECTIVES

The objective of this study was to summarize available data on polymyxin-based combination therapy or monotherapy for carbapenem-resistant Gram-negative bacteria.

METHODS

This is a systematic review. We included observational studies and randomized controlled trials (RCTs) comparing polymyxin monotherapy versus polymyxin-based combination therapy in adult patients with infections caused by carbapenem-resistant or carbapenemase-producing Gram-negative bacteria. Only named antibiotic regimens were included. The primary outcome was 30 day mortality. Unadjusted OR (uOR) and adjusted OR where available with 95% CI were pooled in random-effects meta-analyses.

RESULTS

Twenty-two studies including 28 comparisons were included. Polymyxin monotherapy was associated with a uOR of 1.58 (95% CI = 1.03-2.42) for mortality compared with polymyxin/carbapenem combination therapy (seven observational studies, 537 patients), without heterogeneity. Subgrouping studies to serious and critical risk of bias resulted in uORs of 0.94 (95% CI = 0.42-2.09) and 1.94 (95% CI = 1.17-3.23), respectively. Mortality was significantly higher with polymyxin monotherapy compared with combination therapy with tigecycline, aminoglycosides or fosfomycin (potentially double-coverage regimens): uOR of 1.57 (95% CI = 1.06-2.32) overall (10 observational studies and 1 RCT, 585 patients, no heterogeneity) and uOR of 2.09 (95% CI = 1.21-3.6) for Klebsiella pneumoniae bacteraemia (7 observational studies, 285 patients, no heterogeneity); very low quality evidence. Two RCTs and one observational study assessing rifampicin/colistin combination therapy for Acinetobacter baumannii infections showed no difference in mortality compared with colistin monotherapy; moderate quality evidence.

CONCLUSIONS

The significant association observed in observational studies between polymyxin monotherapy and mortality cannot be taken as proof of combination therapy effects due to the low quality of the evidence. The only three RCTs to date show no effect of rifampicin/colistin or fosfomycin/colistin on mortality for Acinetobacter infections.