Factors associated with bacteraemia due to multidrug-resistant organisms among bacteraemic patients with multidrug-resistant organism carriage: a case control study

Predictors of bacteremia and death, including immune status, in a large single-center cohort of unvaccinated ICU patients with COVID-19 pneumonia

BACKGROUND

We investigated the possible role of the immune profile at ICU admission, among other well characterized clinical and laboratory predictors of unfavorable outcome in COVID-19 patients assisted in ICU.

METHODS

Retrospective analysis of clinical and laboratory data collected for all consecutive patients admitted to the ICUs of the General Hospital of Pescara (Abruzzo, Italy), between 1^st March 2020 and 30^th April 2021, with a confirmed diagnosis of COVID-19 respiratory failure. Logistic regressions were used to identify independent predictors of bacteremia and mortality.

RESULTS

Out of 431 patients included in the study, bacteremia was present in N = 191 (44.3%) and death occurred in N = 210 (48.7%). After multivariate analysis, increased risk of bacteremia was found for viral reactivation (OR = 3.28; 95% CI:1.83-6.08), pronation (3.36; 2.12-5.37) and orotracheal intubation (2.51; 1.58-4.02). Increased mortality was found for bacteremia (2.05; 1.31-3.22), viral reactivation (2.29; 1.29-4.19) and lymphocytes < 0.6 × 10³c/µL (2.32; 1.49-3.64).

CONCLUSIONS

We found that viral reactivation, mostly due to Herpesviridae, was associated with increased risk of both bacteremia and mortality. In addition, pronation and intubation are strong predictors of bacteremia, which in turn together with severe lymphocytopenia due to SARS-CoV2 was associated with increased mortality. Most episodes of bacteremia, even due to Acinetobacter spp, were not predicted by microbiological evidence of colonization.

Short Antibiotic Treatment Duration for Osteomyelitis Complicating Pressure Ulcers: A Quasi-experimental Study

Background

Osteomyelitis-complicating pressure ulcers are frequent among patients with spinal cord injuries (SCIs), and the optimal management is unknown. In our referral center, the current management is debridement and flap coverage surgeries, followed by a short antibiotic treatment. We aimed to evaluate patients' outcomes a year after surgery.

Methods

We performed a quasi-experimental retrospective before/after study on SCI patients with presumed osteomyelitis associated with perineal pressure ulcers. We included all patients who underwent surgery with debridement and flap covering, followed by effective antibiotic treatment, between May 1, 2016, and October 30, 2020. The effective antimicrobial treatment duration included the 10 days leading up to January 1, 2018 (before period), and the 5 to 7 days after (after period). We also compared the efficacy of 5-7-day vs 10-day antibiotic treatment and performed uni- and multivariable analyses to identify factors associated with failure.

Results

Overall, 415 patients were included (77.6% male patients; mean age ± SD, 53.0 ± 14.4 years). Multidrug-resistant organisms (MDROs) were involved in 20.7% of cases. Favorable outcomes were recorded in 69.2% of cases: 117/179 (65.3%) in the 10-day treatment group vs 169/287 (71.9%) in the 5-7-day treatment group (P = .153). The only factor associated with failure in the multivariate analysis was a positive culture from suction drainage (odds ratio, 1.622; 95% CI, 1.005-2.617; P = .046). Effective treatment duration >7 days and intraoperative samples negative for MDROs were not associated with better outcomes (P = .153 and P = .241, respectively).

Conclusions

A treatment strategy combining surgical debridement and flap covering, followed by 5 to 7 days of effective antibiotic treatment seems safe.

Risk factors associated with bacteremia with drug-resistant organisms: Review of blood culture results in emergency department of a regional hospital

Background:

Early antibiotic administration in sepsis improves patient survival. Treatment with antibiotics should cover potential pathogens and should avoid overusing broad-spectrum antibiotics. We have to identify patients who have high risks of infection with drug-resistant organisms.

Objectives:

A retrospective cohort study was conducted to identify potential risk factors associated with bloodstream infections with drug-resistant organisms to help the choice of empirical antibiotics in the emergency department.

Methods:

Adult patients with bloodstream infection diagnosed by blood culture in the emergency department in the period of 1 January 2020 to 31 December 2020 were included. Clinical features including chronic medical illnesses, clinical presentation and severity, and patients’ outcomes were identified in the electronic medical records. Bloodstream infection with drug-resistant organisms is defined as positive blood culture with bacteria resistant to either (1) amoxicillin/ clavulanic acid AND ceftriaxone or (2) amoxicillin/ clavulanic acid or ceftriaxone PLUS amikacin or levofloxacin. Univariate and multivariate analyses were conducted to identify risk factors associated with the study outcome.

Results:

Among 105 patients with bloodstream infection, 17% were caused by drug-resistant organisms. Multivariate analysis showed that age is a risk factor associated with bloodstream infection with drug-resistant organisms (odds ratio: 1.04, 95% confidence interval: 1.0–1.08, p = 0.03).

Conclusion:

In conclusion, age is a significant risk factor for drug-resistant bloodstream infection in emergency department patients. Further research may be needed to find out the relationship between frailty and infection with drug-resistant organisms.

The threat of multidrug-resistant/extensively drug-resistant Gram-negative respiratory infections: another pandemic

Antibiotic resistance is recognised as a global threat to human health by national healthcare agencies, governments and medical societies, as well as the World Health Organization. Increasing resistance to available antimicrobial agents is of concern for bacterial, fungal, viral and parasitic pathogens. One of the greatest concerns is the continuing escalation of antimicrobial resistance among Gram-negative bacteria resulting in the endemic presence of multidrug-resistant (MDR) and extremely drug-resistant (XDR) pathogens. This concern is heightened by the identification of such MDR/XDR Gram-negative bacteria in water and food sources, as colonisers of the intestine and other locations in both hospitalised patients and individuals in the community, and as agents of all types of infections. Pneumonia and other types of respiratory infections are among the most common infections caused by MDR/XDR Gram-negative bacteria and are associated with high rates of mortality. Future concerns are already heightened due to emergence of resistance to all existing antimicrobial agents developed in the past decade to treat MDR/XDR Gram-negative bacteria and a scarcity of novel agents in the developmental pipeline. This clinical scenario increases the likelihood of a future pandemic caused by MDR/XDR Gram-negative bacteria.

Multidrug-Resistant Bloodstream Infections in Internal Medicine: Results from a Single-Center Study

OBJECTIVES

Infections due to multidrug-resistant organisms (MDROs) are expanding globally and are associated with higher mortality rates and hospital-related costs. The objectives of this study were to analyze the trends of MDRO bacteremia and antimicrobial resistance rates in Internal Medicine wards of our hospital and to identify the variables associated with these infections.

METHODS

During a 6-year period (July 1, 2011-June 30, 2017), patients with positive blood culture isolates hospitalized in the Internal Medicine wards in the Santa Croce and Carle Hospital in Cuneo, Italy, were assessed. We performed an analysis taking into consideration the time trends and frequencies of MDRO infections, as well as a case-control study to identify clinical-demographic variables associated with MDRO bacteremias.

RESULTS

During the study period a total of 596 blood cultures were performed in 577 patients. The most frequently identified organism was Escherichia coli (33.7%), followed by Staphylococcus aureus (15.6%) and S epidermidis (7.4%). The percentage of resistance to methicillin among S aureus isolates showed a decreasing trend, whereas rates of extended-spectrum β-lactamase-producing Enterobacteriaceae and carbapenemase-producing Klebsiella pneumoniae increased during the study period. Multivariate analysis showed that the nosocomial origin of the infection, hospitalization during the previous 3 months, residence in long-term care facilities, presence of a device, antibiotic exposure during the previous 3 months, and cerebrovascular disease were independently associated with bacteremia by resistant microorganisms.

CONCLUSIONS

Our analysis reveals a concerning microbiological situation in an Internal Medicine setting, in line with other national and regional data. The risk variables for infection by MDRO identified in our study correspond to those reported in the literature, although studies focused on Internal Medicine settings appear to be limited.

Profiles of multidrug-resistant organisms among patients with bacteremia in intensive care units: an international ID-IRI survey

Evaluating trends in antibiotic resistance is a requisite. The study aimed to analyze the profile of multidrug-resistant organisms (MDROs) among hospitalized patients with bacteremia in intensive care units (ICUs) in a large geographical area. This is a 1-month cross-sectional survey for blood-borne pathogens in 57 ICUs from 24 countries with different income levels: lower-middle-income (LMI), upper-middle-income (UMI), and high-income (HI) countries. Multidrug-resistant (MDR), extensively drug-resistant (XDR), or pan-drug-resistant isolates were searched. Logistic regression analysis determined resistance predictors among MDROs. Community-acquired infections were comparable to hospital-acquired infections particularly in LMI (94/202; 46.5% vs 108/202; 53.5%). Although MDR (65.1%; 502/771) and XDR (4.9%; 38/771) were common, no pan-drug-resistant isolate was recovered. In total, 32.1% of MDR were Klebsiella pneumoniae, and 55.3% of XDR were Acinetobacter baumannii. The highest MDR and XDR rates were in UMI and LMI, respectively, with no XDR revealed from HI. Predictors of MDR acquisition were male gender (OR, 12.11; 95% CI, 3.025-15.585) and the hospital-acquired origin of bacteremia (OR, 2.643; 95%CI, 1.462-3.894), and XDR acquisition was due to bacteremia in UMI (OR, 3.344; 95%CI, 1.189-5.626) and admission to medical-surgical ICUs (OR, 1.481; 95% CI, 1.076-2.037). We confirm the urgent need to expand stewardship activities to community settings especially in LMI, with more paid attention to the drugs with a higher potential for resistance. Empowering microbiology laboratories and reports to direct prescribing decisions should be prioritized. Supporting stewardship in ICUs, the mixed medical-surgical ones in particular, is warranted.

Prevalence of multidrug-resistant bacteria in Ethiopia: a systematic review and meta-analysis

OBJECTIVES

Multidrug-resistant (MDR) bacteria are a significant public-health threat worldwide, especially in low- and middle-income countries. Comprehensive data are important to understand the magnitude of multidrug resistance (MDR), however these are not available in Ethiopia.

METHODS

Five electronic databases and grey literature of Addis Ababa University Repository were searched for data regarding the prevalence of MDR bacteria in Ethiopia. OpenMetaAnalyst R1.3 was used for analysis using a random-effects model to determine the effect size. Heterogeneity among articles was checked using the inconsistency index (I²). Funnel plot was used to check for publication bias. The quality of each article was checked using the Newcastle-Ottawa checklist adapted for cross-sectional studies.

RESULTS

Through database searching, 2094 articles were identified, of which 37 fulfilled the study inclusion criteria. This review comprises 6856 bacteria, of which 4949 isolates were MDR. The overall pooled prevalence of MDR was 70.5% (95% CI 64.9-76.1%), with considerable heterogeneity (I² = 97.48%, P < 0.001). Funnel plot revealed no publication bias. Sidama (81.7%) had the highest MDR and Tigray (51.1%) the lowest. The greatest source of MDR was from multiple sites of infection (MSI) (76.8%); the least was from bloodstream infections (62.9%). MDR was higher in studies conducted on hospital-acquired infections (72.1%) compared with both hospital- and community-acquired infections (69.8%).

CONCLUSION

Our study indicates a high prevalence of MDR in Ethiopia. Sidama region, MSI and hospital-acquired infections showed the highest MDR in subgroup analysis. Regional hospitals should implement infection prevention and proper use of antibiotics in the community.

Adverse clinical outcomes associated with infections by Enterobacterales producing ESBL (ESBL-E): a systematic review and meta-analysis

OBJECTIVES

Enterobacterales producing ESBL (ESBL-E) have been notable for their rapid expansion in community settings. This systematic review and meta-analysis aimed to summarize evidence investigating the association between ESBL-E infection and adverse clinical outcomes, defined as bacteraemia, sepsis or septic shock, and all-cause mortality in adult patients.

METHODS

Database search was conducted in PubMed, Scopus and EMBASE. In general, studies were screened for effect estimates of ESBL-E colonization or infection on clinical outcomes with non-ESBL-producing Enterobacterales as comparator, adult populations and molecular ascertainment of ESBL gene. Meta-analysis was performed using the inverse variance heterogeneity model.

RESULTS

Eighteen studies were identified, including 1399 ESBL-E and 3200 non-ESBL-E infected patients. Sixteen of these studies included only bacteraemic patients. Mortality was studied in 17 studies and ESBL-E infection was significantly associated with higher odds of mortality compared with non-ESBL-producing Enterobacterales infection (OR = 1.70, 95% CI: 1.15-2.49, I 2=58.3%). However, statistical significance did not persist when adjusted estimates were pooled (aOR = 1.67, 95% CI: 0.52-5.39, I 2=78.1%). Septic shock was studied in seven studies and all included only bacteraemic patients. No association between ESBL-E infection and shock was found (OR = 1.23, 95% CI: 0.75-2.02, I 2=14.8%). Only one study investigated the association between ESBL-E infection and bacteraemia.

CONCLUSIONS

Infections by ESBL-E appear to be significantly associated with mortality but not septic shock. Available studies investigating bacteraemia and shock as an intermediate outcome of ESBL-E infections are lacking. Future studies investigating the relationship between clinical outcomes and molecular characteristics of resistant strains are further warranted, along with studies investigating this in non-bacteraemic patients.

Early Screening of Risk for Multidrug-Resistant Organisms in the Emergency Department in Patients With Pneumonia and Early Septic Shock: Single-Center, Retrospective Cohort Study

OBJECTIVES

Pneumonia is the fourth leading cause of death globally, with rapid progression during sepsis. Multidrug-resistant organisms (MDROs) are becoming more common with some healthcare-associated pneumonia events. Early detection of MDRO risk improves the outcomes; however, MDROs risk in pneumonia with sepsis is unknown. This study investigated the disease outcomes of pneumonia with septic shock in patients admitted in the emergency department (ED) intensive care unit (ICU), a population with a high prevalence of MDROs, after early screening of MDROs risk.

METHODS

In this retrospective cohort study, patients with pneumonia and early septic shock (n = 533) admitted to the ED at the Taipei Tzu Chi Hospital from 2013 to 2019 were selected. The study population was divided into four subgroups after the MDROs risk and screening procedure were completed within 1 or 6 h of admission. ICU mortality and multidrug antibiotic therapy were compared.

RESULTS

The high-risk MDROs groups had higher percentage of P aeruginosa than the low-risk group. Furthermore, the appropriate ED first antibiotics were higher in the 1-h subgroup than in the 6-h subgroup of the high-risk MDROs group. In multivariate analysis, the 6-h high-risk MDROs group had an adjusted odds ratio of 7.191 (95% CI: 2.911-17.767, P < 0.001) and 2.917 (95% CI: 1.456-5.847, P = 0.003) for ICU mortality and multidrug therapy in the ICU, respectively, after adjusting for other confounding factors.

CONCLUSIONS

MDRO screening within 1 h is recommended following admission of patients with pneumonia and early septic shock in the ED, especially in areas with a high prevalence of MDROs.

Whole Genome Sequencing of Ceftolozane-Tazobactam and Ceftazidime-Avibactam Resistant Pseudomonas aeruginosa Isolated from a Blood Stream Infection Reveals VEB and Chromosomal Metallo-Beta Lactamases as Genetic Determinants: A Case Report

Pseudomonas aeruginosa is a common gram-negative bacillus in nosocomial settings. Consideration of this organism is important due to its potential to acquire multi-drug resistance through various mechanisms causing severe infections, particularly in immunocompromised hosts. Here, we present a challenging case of a blood stream infection caused by a drug-resistant strain of P. aeruginosa in a debilitated young patient. A 31-year-old male patient with a complex history of multiple trauma following a vehicle accident that required several surgical interventions, is plagued by persistent bacteremia. An extensively drug-resistant strain of P. aeruginosa was repeatedly isolated that continued to grow in the patient's blood cultures despite treatment with meropenem and colistin for an extended period. In addition to phenotypic characterization, the complete genome of the strain was sequenced and a genomic view was provided regarding its antimicrobial resistance (AMR) patterns, efflux pump genes, virulence determinants, phageomic signals, and genomic islands. The strain belongs to sequence type ST357 with dominant Class A (VEB), Class B, Class C (PDC-11) and D (OXA-10, OXA-50) β-lactamases, and injectosomes (type III secretion system) known to mediate high virulence. The pool of extended spectrum β-lactamases genes and the upregulated chromosomal efflux system are likely to account for the extended resistance pattern in this strain. In light of the global spread of ST357 isolates, it is essential to continue monitoring their resistance patterns and evaluate effective epidemiological tools to define the genetic determinants of emerging resistance. Intensified infection control measures are continuously required to stop dissemination of such strains in an institution where susceptible hosts are at risk of acquiring them.

Comparison of surveillance and clinical cultures to measure the impact of infection control interventions on the incidence of methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus in the hospital

OBJECTIVE

To evaluate whether clinical cultures are an appropriate surrogate for surveillance cultures to measure the effect of interventions on the incidence of MRSA and VRE in the hospital.

DESIGN

Cross-sectional and quasi-experimental, retrospective analysis.

SETTING AND POPULATION

Convenience sample of patients admitted between January 1, 2002, and June 31, 2011, to the medical intensive care unit (MICU) and surgical intensive care unit (SICU) of an acute-care hospital in the United States.

INTERVENTIONS

Asynchronously in the MICU and SICU, we introduced (1) universal glove and gown use, (2) bundled intervention to prevent central-line-associated bloodstream infection, and (3) daily chlorhexidine gluconate bathing.

RESULTS

We observed a statistically significant correlation between surveillance and clinical culture-based incidence rates of MRSA in the MICU (0.32; P < .001) and the SICU (0.37; P < .001) but not for VRE in either the MICU (0.16, P = .11) or the SICU (0.15; P = .12). For VRE, but not for MRSA, incidence density rates based on surveillance cultures were 2- to 4-fold higher than for clinical cultures. When evaluating the impacts of the interventions, different effect estimates were noted for universal glove and gown use on MRSA acquisition in MICU, and for VRE acquisition in both the MICU and the SICU based on surveillance versus clinical cultures.

CONCLUSIONS

For multidrug-resistant organism acquisition, surveillance cultures should be used when feasible because clinical cultures may not be an appropriate surrogate. Clinical or surveillance-based end points for infection control interventions should reflect the conceptual model from colonization to infection and where an intervention might have an effect, rather than considering them interchangeable.

Epidemiology of Vancomycin-Resistant Enterococcus faecium and Enterococcus faecalis Colonization in Nursing Facilities

BACKGROUND

Vancomycin-resistant Enterococcus faecium and Enterococcus faecalis frequently colonize nursing facility (NF) residents, creating opportunities for vancomycin-resistant Enterococcus (VRE) transmission and dissemination of mobile genetic elements conferring antimicrobial resistance. Most VRE studies do not speciate; our study addresses this lack and compares the epidemiology of E faecium and E faecalis.

METHODS

We enrolled 651 newly admitted patients from 6 different NFs and collected swabs from several body sites at enrollment, 14 days, 30 days, and monthly thereafter for up to 6 months. The VRE were speciated using a duplex polymerase chain reaction. We used multinomial logistic regression models to compare risk factors associated with colonization of E faecium and E faecalis.

RESULTS

Overall, 40.7% were colonized with E faecium, E faecalis, or both. At enrollment, more participants were colonized with E faecium (17.8%) than E faecalis (8.4%); 3.2% carried both species. Enterococcus faecium was carried twice as long as E faecalis (69 days and 32 days, respectively), but incidence rates were similar (E faecium, 3.9/1000 person-days vs E faecalis, 4.1/1000 person-days). Length of stay did not differ by species among incident cases. Residents who used antibiotics within the past 30 days had a greater incidence of both E faecium (odds ratio [OR] = 2.89; 95% confidence interval [CI], 1.82-4.60) and E faecalis (OR = 1.80; 95% CI, 1.16-2.80); device use was most strongly associated with the incidence of E faecium colonization (OR = 2.01; 95% CI, 1.15-3.50).

CONCLUSIONS

Recent increases in vancomycin-resistant E faecium prevalence may reflect increased device use and longer duration of carriage.