Risk factors for the first episode of Klebsiella pneumoniae resistant to carbapenems infection in critically ill patients: a prospective study

Clinical Management of a Pandrug-Resistant OXA-48 Klebsiella pneumoniae Infection in the Pediatric Intensive Care Unit

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is one of the serious forms of health care-associated infection. Pan-drug resistant (PDR) CRKP infections can cause severe infections. Mortality and treatment costs in the pediatric intensive care unit (PICU) are high. This study aims to share our experience regarding the treatment of oxacillinase (OXA)-48-positive PDR-CRKP infection in our 20-bed tertiary PICU with isolated rooms and 1 nurse for every 2-3 patients. Methods: Patient demographic characteristics, underlying diseases, previous infections, source of infection PDR-CRKP, treatment modalities, measures used, and outcomes were recorded. Findings: Eleven patients (eight men and three women) were found to have PDR OXA-48-positive CRKP. Because of the simultaneous detection of PDR-CRKP in three patients and the rapid spread of the disease, it was classified as a clinical outbreak, and strict infection control measures were taken. Combination therapy with double carbapenemase (meropenem and imipenem), amikacin, colistin, and tigecycline was used for treatment. The mean duration of treatment and isolation was 15.7 and 65.4 days, respectively. No treatment-related complication was observed, only one patient died, and the mortality rate was 9%. Conclusions: This severe clinical outbreak can be successfully treated with effective treatment with combined antibiotics and strict adherence to infection control measures. ClinicalTrial.gov ID: 28/01/2022 - 1/5.

Incidence and Risk Factors for Blood Stream Infection in Mechanically Ventilated COVID-19 Patients

It is widely known that blood stream infections (BSIs) in critically ill patients may affect mortality, length of stay, or the duration of mechanical ventilation. There is scarce data regarding blood stream infections in mechanically ventilated COVID-19 patients. Preliminary studies report that the number of secondary infections in COVID-9 patients may be higher. This retrospective analysis was conducted to determine the incidence of BSI. Furthermore, risk factors, mortality, and other outcomes were analyzed. The setting was an Intensive Care Unit (ICU) at a University Hospital. Patients suffering from SARS-CoV-2 infection and requiring mechanical ventilation (MV) for >48 h were eligible. The characteristics of patients who presented BSI were compared with those of patients who did not present BSI. Eighty-four patients were included. The incidence of BSI was 57%. In most cases, multidrug-resistant pathogens were isolated. Dyslipidemia was more frequent in the BSI group (p < 0.05). Moreover, BSI-group patients had a longer ICU stay and a longer duration of both mechanical ventilation and sedation (p < 0.05). Deaths were not statistically different between the two groups (73% for BSI and 56% for the non-BSI group, p > 0.05). Compared with non-survivors, survivors had lower baseline APACHE II and SOFA scores, lower D-dimers levels, a higher baseline compliance of the respiratory system, and less frequent heart failure. They received anakinra less frequently and appropriate therapy more often (p < 0.05). The independent risk factor for mortality was the APACHE II score [1.232 (1.017 to 1.493), p = 0.033].

Prior Antibiotic Therapy and the Onset of Healthcare-Associated Infections Sustained by Multidrug-Resistant Klebsiella pneumoniae in Intensive Care Unit Patients: A Nested Case-Control Study

Epidemiological research has demonstrated direct relationships between antibiotic consumption and the emergence of multidrug-resistant (MDR) bacteria. In this nested case-control study, we assessed whether prior exposure to antibiotic therapy and its duration affect the onset of healthcare-associated infections (HAIs) sustained by MDR Klebsiella pneumoniae (MDR-Kp) in intensive care unit patients. Cases were defined as patients who developed an MDR-Kp HAI. Controls matched on sex and the length of intensive care unit (ICU) stay were randomly selected from the at-risk population. Any antibiotic agent received in systemic administration before the onset of infection was considered as antibiotic exposure. Multivariable conditional logistic regression analyses were performed to estimate the effect of prior exposure to each antibiotic class (Model 1) or its duration (Model 2) on the onset of HAIs sustained by MDR-Kp. Overall, 87 cases and 261 gender-matched controls were compared. In Model 1, aminoglycosides and linezolid independently increased the likelihood of developing an MDR-Kp HAI, whereas exposure to both linezolid and penicillins reduced the effect of linezolid alone. In Model 2, cumulative exposure to aminoglycosides increased the likelihood of the outcome, as well as cumulative exposures to penicillins and colistin, while a previous exposure to both penicillins and colistin reduced the influence of the two antibiotic classes alone. Our study confirms that aminoglycosides, penicillins, linezolid, and colistin may play a role in favoring the infections sustained by MDR-Kp. However, several double exposures in the time window before HAI onset seemed to hinder the selective pressure exerted by individual agents.

Clinical Observation and Prognostic Analysis of Patients With Klebsiella pneumoniae Bloodstream Infection

Background and purpose

The clinical prognosis of Klebsiella pneumoniae(K. pneumoniae) bloodstream infection is poor, and the prevalence of drug-resistant bacteria makes clinical anti-infective treatment more challenging. This retrospective study evaluated the epidemiological characteristics of patients with K. pneumoniae, the risk factors for drug-resistant bacterial infection and death, and analyzed treatment options.

Methods

Clinical data of 297 patients diagnosed with K. pneumoniae bacteremia between June 2014 and June 2019 were collected.

Results

Intensive care unit hospitalization history, operation history, recent antibiotic use history, mechanical ventilation, and number of days hospitalized before bloodstream infection were found to be independent risk factors for drug-resistant bacterial infection. The risk of death for carbapenem-resistant K. pneumoniae infection was 2.942 times higher than that for carbapenem-sensitive K. pneumoniae infection. For extensively drug-resistant K. pneumoniae bacteremia patients, the mortality rate of combined anti-infective therapy was lower.

Conclusions

Clinicians should pay attention to patients with high-risk drug-resistant bacteria infection and administer timely anti-infection treatment. The findings of this study may provide some suggestions for early identification and standardized treatment of patients with K. pneumoniae bacteremia.

Ceftazidime-Avibactam To Treat Life-Threatening Infections by Carbapenem-Resistant Pathogens in Critically Ill Mechanically Ventilated Patients

Data on the effectiveness of ceftazidime-avibactam (CAZ-AVI) in critically ill, mechanically ventilated patients are limited. The present retrospective observational cohort study, which was conducted in two general intensive care units (ICUs) in central Greece, compared critically ill, mechanically ventilated patients suffering from carbapenem-resistant Enterobacteriaceae (CRE) infections receiving CAZ-AVI to patients who received appropriate available antibiotic therapy. Clinical and microbiological outcomes and safety issues were evaluated. A secondary analysis in patients with bloodstream infections (BSIs) was conducted. Forty-one patients that received CAZ-AVI (the CAZ-AVI group) were compared to 36 patients that received antibiotics other than CAZ-AVI (the control group). There was a significant improvement in the Sequential Organ Failure Assessment (SOFA) score on days 4 and 10 in the CAZ-AVI group compared to that in the control group (P = 0.006, and P = 0.003, respectively). Microbiological eradication was accomplished in 33/35 (94.3%) patients in the CAZ-AVI group and 21/31 (67.7%) patients in the control group (P = 0.021), and clinical cure was observed in 33/41 (80.5%) versus 19/36 (52.8%) patients (P = 0.010), respectively. The results were similar in the BSI subgroups for both outcomes (P = 0.038 and P = 0.014, respectively). The 28-day survival was 85.4% in the CAZ-AVI group and 61.1% in the control group (log-rank test = 0.035), while there were 2 and 12 relapses in the CAZ-AVI and control groups, respectively (P = 0.042). A CAZ-AVI-containing regime was an independent predictor of survival and clinical cure (odds ratio [OR] = 5.575 and P = 0.012 and OR = 5.125 and P = 0.004, respectively), as was illness severity. No significant side effects were recorded. In conclusion, a CAZ-AVI-containing regime was more effective than other available antibiotic agents for the treatment of CRE infections in the high-risk, mechanically ventilated ICU population evaluated.

Risk factors for the first episode of Acinetobacter baumannii resistant to colistin infection and outcome in critically ill patients

Introduction

To identify risk factors for the first episode of Acinetobacter baumannii resistant to colistin (ABCR) infection in critically ill patients.

Aim

Prospective observational study.

Methodology

ICU patients who required mechanical ventilation for >48 h during a 36 month period. Clinical and microbiological data were studied; characteristics of patients infected with ABCR were compared with those of critically ill patients who presented infection due to A. baumannii sensitive to colistin (ABCS).

Results

Twenty patients presented with ABCR infection, and 57 patients ABCS infection. Compared to patients with ABCS infection, patients suffering from ABCR infection had received more frequent and/or for longer duration dosing of several antibiotics active against Gram-negative bacteria (P<.05). Moreover, the duration of mechanical ventilation, and the presence of invasive procedures and tracheostomy prior to infection were associated with ABCR infections. The duration of carbapenem administration was an independent risk factor for ABCR infection [odds ratio (OR), 1.21; 95 % confidence interval (95 %, CI), 1.00 to 1.45; P=.049]. Mortality rate for patients with ABCR infection was higher (85 vs 39 % for the ABCS group). Sequential organ failure assessment score on admission, Charlson score and ABCR infection were independent risk factors for mortality.

Conclusion

ABCR infection is a life-threatening infection, which might be more common in patients with previous use of antibiotics, especially carbapenems.

Subtractive Genomics, Molecular Docking and Molecular Dynamics Simulation Revealed LpxC as a Potential Drug Target Against Multi-Drug Resistant Klebsiella pneumoniae

The emergence and dissemination of pan drug resistant clones of Klebsiella pneumoniae are great threat to public health. In this regard new therapeutic targets must be highlighted to pave the path for novel drug discovery and development. Subtractive proteomic pipeline brought forth UDP-3-O-[3-hydroxymyristoyl] N-acetylglucosamine deacetylase (LpxC), a Zn⁺² dependent cytoplasmic metalloprotein and catalyze the rate limiting deacetylation step of lipid A biosynthesis pathway. Primary sequence analysis followed by 3-dimensional (3-D) structure elucidation of the protein led to the detection of K. pneumoniae LpxC (KpLpxC) topology distinct from its orthologous counterparts in other bacterial species. Molecular docking study of the protein recognized receptor antagonist compound 106, a uridine-based LpxC inhibitory compound, as a ligand best able to fit the binding pocket with a Gold Score of 67.53. Molecular dynamics simulation of docked KpLpxC revealed an alternate binding pattern of ligand in the active site. The ligand tail exhibited preferred binding to the domain I residues as opposed to the substrate binding hydrophobic channel of subdomain II, usually targeted by inhibitory compounds. Comparison with the undocked KpLpxC system demonstrated ligand induced high conformational changes in the hydrophobic channel of subdomain II in KpLpxC. Hence, ligand exerted its inhibitory potential by rendering the channel unstable for substrate binding.

A Systematic Review and Meta-analyses of the Clinical Epidemiology of Carbapenem-Resistant Enterobacteriaceae

Carbapenem-resistant Enterobacteriaceae (CRE) are major health care-associated pathogens and responsible for hospital outbreaks worldwide. To prevent a further increase in CRE infections and to improve infection prevention strategies, it is important to summarize the current knowledge about CRE infection prevention in hospital settings. This systematic review aimed to identify risk factors for CRE acquisition among hospitalized patients. In addition, we summarized the environmental sources/reservoirs and the most successful infection prevention strategies related to CRE. A total of 3,983 potentially relevant articles were identified and screened. Finally, we included 162 studies in the systematic review, of which 69 studies regarding risk factors for CRE acquisition were included in the random-effects meta-analysis studies. The meta-analyses regarding risk factors for CRE acquisition showed that the use of medical devices generated the highest pooled estimate (odds ratio [OR] = 5.09; 95% confidence interval [CI] = 3.38 to 7.67), followed by carbapenem use (OR = 4.71; 95% CI = 3.54 to 6.26). To control hospital outbreaks, bundled interventions, including the use of barrier/contact precautions for patients colonized or infected with CRE, are needed. In addition, it is necessary to optimize the therapeutic approach, which is an important message to infectious disease specialists, who need to be actively involved in a timely manner in the treatment of patients with known CRE infections or suspected carriers of CRE.

Piperacillin-tazobactam as alternative to carbapenems for ICU patients

Several studies suggest that alternatives to carbapenems, and particulary beta-lactam/beta-lactamase inhibitor combinations, can be used for therapy of extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-PE)-related infections in non-ICU patients. Little is known concerning ICU patients in whom achieving the desired plasmatic pharmacokinetic/pharmacodynamic (PK/PD) target may be difficult. Also, in vitro susceptibility to beta-lactamase inhibitors might not translate into clinical efficacy. We reviewed the recent clinical studies examining the use of BL/BLI as alternatives to carbapenems for therapy of bloodstream infection, PK/PD data and discuss potential ecological benefit from avoiding the use of carbapenems. With the lack of prospective randomized studies, treating ICU patients with ESBL-PE-related infections using piperacillin-tazobactam should be done with caution. Current data suggest that BL/BLI empirical use should be avoided for therapy of ESBL-PE-related infection. Also, definitive therapy should be reserved to patients in clinical stable condition, after microbial documentation and results of susceptibility tests. Optimization of administration and higher dosage should be used in order to reach pharmacological targets.

Evaluation of early antimicrobial therapy adaptation guided by the BetaLACTA® test: a case-control study

Background

Rapid diagnostic tests detecting microbial resistance are needed for limiting the duration of inappropriateness of empirical antimicrobial therapy (EAT) in intensive care unit patients, besides reducing the use of broad-spectrum antibiotics. We hypothesized that the betaLACTA® test (BLT) could lead to early increase in the adequacy of antimicrobial therapy.

Methods

This was a case-control study. Sixty-one patients with BLT-guided adaptation of EAT were prospectively included, and then matched with 61 “controls” having similar infection characteristics (community or hospital-acquired, and source of infection), in whom EAT was conventionally adapted to antibiogram results. Endpoints were to compare the proportion of appropriate (primary endpoint) and optimal (secondary endpoint) antimicrobial therapies with each of the two strategies, once microbiological sample culture results were available.

Results

Characteristics of patients, infections and EAT at inclusion were similar between groups. Nine early escalations of EAT occurred in the BLT-guided adaptation group, reaching 98% appropriateness vs. 77% in the conventional adaptation group (p < 0.01). The BLT reduced the time until escalation of an inappropriate EAT from 50.5 (48–73) to 27 (24–28) hours (p < 0.01). Seventeen early de-escalations occurred in the BLT-guided adaptation group, compared to one in the conventional adaptation group, reducing patients’ exposure to broad-spectrum beta-lactam such as carbapenems. In multivariate analysis, use of the BLT was strongly associated with early appropriate (OR = 18 (3.4–333.8), p = 0.006) and optimal (OR = 35.5 (9.6–231.9), p < 0.001) antimicrobial therapies. Safety parameters were similar between groups.

Conclusions

Our study suggests that a BLT-guided adaptation strategy may allow early beta-lactam adaptation from the first 24 hours following the beginning of sepsis management.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1746-6) contains supplementary material, which is available to authorized users.

Carbapenemase-producing Enterobacteriaceae: Risk factors for infection and impact of resistance on outcomes

BACKGROUND

Carbapenemase-producing Enterobacteriaceae (CPE) have increased in recent years leading to limitations of treatment options. The present study was undertaken to detect CPE, risk factors for acquiring them and their impact on clinical outcomes.

METHODS

This retrospective observational study included 111 clinically significant Enterobacteriaceae resistant to cephalosporins subclass III and exhibiting a positive modified Hodge test. Screening for carbapenemase production was done by phenotypic methods, and polymerase chain reaction was performed to detect genes encoding them. Retrospectively, the medical records of the patients were perused to assess risk factors for infections with CPE and their impact. The data collected were duration of hospital stay, Intensive Care Unit (ICU) stay, use of invasive devices, mechanical ventilation, the presence of comorbidities, and antimicrobial therapy. The outcome was followed up. Univariate and multivariate analysis of the data were performed using SPSS software.

RESULTS

Carbapenemase-encoding genes were detected in 67 isolates. The genes detected were New Delhi metallo-β-lactamase, Verona integron-encoded metallo-β-lactamase, and oxacillinase-181.Although univariate analysis identified risk factors associated with acquiring CPE infections as ICU stay (P = 0.021), mechanical ventilation (P = 0.013), indwelling device (P = 0.011), diabetes mellitus (P = 0.036), usage of multiple antimicrobial agents (P = 0.007), administration of carbapenems (P = 0.042), presence of focal infection or sepsis (P = 0.013), and surgical interventions (P = 0.016), multivariate analysis revealed that all these factors were insignificant. Mortality rate was 56.7% in patients with CPE infections. By both univariate and multivariate analysis of impact of the variables on mortality in these patients, the significant factors were mechanical ventilation (odds ratio [OR]: 0.141, 95% confidence interval [CI]: 0.024-0.812) and presence of indwelling invasive device (OR: 8.034; 95% CI: 2.060-31.335).

CONCLUSION

In this study, no specific factor was identified as an independent risk for acquisition of CPE infection. However, as it is evident by multivariate analysis, there is an increased risk of mortality in patients with CPE infections when they are ventilated and are supported by indwelling devices.

Colonization pressure as a risk factor of ICU-acquired multidrug resistant bacteria: a prospective observational study

The primary objective of this study was to evaluate the impact of colonization pressure on intensive care unit (ICU)-acquired multidrug resistant bacteria (MDRB). All patients hospitalized for more than 48 h in the ICU were included in this prospective observational study. MDRB were defined as methicillin resistant Staphylococcus aureus, Pseudomonas aeruginosa resistant to ceftazidime or imipenem, Gram-negative bacilli producing extended-spectrum beta-lactamases (ESBL), and all strains of Acinetobacter baumannii and Stenotrophomonas maltophilia. Colonization pressure was daily calculated in the three participating ICUs. Univariate and multivariate analyses were used to determine risk factors for ICU-acquired MDRB. Two hundreds and four (34%) of the 593 included patients acquired an MDRB during their ICU stay. Multivariate analysis identified colonization pressure as an independent risk factor for ICU-acquired MDRB (OR (95% CI) 4.18 (1.03-17.01), p = 0.046). Other independent risk factors for ICU-acquired MDRB were mechanical ventilation (3.08 (1.28-7.38), p = 0.012), and arterial catheter use (OR, 3.04 (1.38-6.68), p = 0.006). ICU-acquired MDRB were associated with increased mortality, duration of mechanical ventilation, and ICU stay. However, ICU-acquired MDRB was not independently associated with ICU-mortality. Colonization pressure is an independent risk factor for acquiring MDRB in the ICU.

Multidrug-Resistant Escherichia coli and Klebsiella pneumoniae Isolated From Patients in Kashan, Iran

BACKGROUND

Escherichia coli and Klebsiella pneumoniae are common human pathogens that cause a wide spectrum of infections. Antimicrobial resistance is a basic obstacle in the management of these infections which has different patterns in various regions.

OBJECTIVES

In this study, the antibiotic resistance patterns and risk factors for multidrug-resistant (MDR) E. coli and K. pneumoniae were determined.

PATIENTS AND METHODS

In this cross-sectional study, a total of 250 isolates (134 E. coli and 116 K. pneumoniae) were collected and antimicrobial resistances to ampicillin, amoxicillin-clavulanic acid, amikacin, gentamycin, ceftriaxone, ceftazidime, ciprofloxacin and imipenem were evaluated by disc diffusion method and confirmed by E-test. Moreover, risk factors for MDR E. coli and K. pneumoniae were also detected.

RESULTS

The mean ages of the culture-positive cases of E. coli and K. pneumoniae were 33.39 ± 24.42 and 36.54 ± 24.66 years, respectively (P = 0.31); 137 (54.8%) cases were male and 113 (45.2%) were female (P = 0.53). Nineteen (14.2%) isolates of E. coli and 12 (10.3%) isolates of K. pneumoniae were sensitive to all the evaluated antibiotics. The prevalence of MDR E. coli and MDR K. pneumoniae was 50% and 46.6%, respectively (P = 0.59). The highest resistance for both strains was to ampicillin and no imipenem resistance was seen. The risk factors for MDR E. coli were admission history during the recent three months (P = 0.043) and antibiotic use in the previous month (P = 0.03); for MDR K. pneumoniae, they were admission in the pediatric ward (P = 0.016), surgical ward (P = 0.019), or gynecology ward (P = 0.12), admission duration of > seven days, and antibiotic use during the past month (P = 0.04).

CONCLUSIONS

The prevalence of multidrug resistance was high compared with developed countries, and history of admission, antibiotic use, admission duration and admission wards were the risk factors for multidrug resistance.

Acinetobacter baumannii infection in prior ICU bed occupants is an independent risk factor for subsequent cases of ventilator-associated pneumonia

OBJECTIVE

We aimed to evaluate risk factors for ventilator-associated pneumonia (VAP) due to Acinetobacter baumannii (AbVAP) in critically ill patients.

METHODS

This was a prospective observational study conducted in an intensive care unit (ICU) of a district hospital (6 beds). Consecutive patients were eligible for enrolment if they required mechanical ventilation for >48 hours and hospitalization for >72 hours. Clinical, microbiological, and laboratory parameters were assessed as risk factors for AbVAP by univariate and multivariate analysis.

RESULTS

193 patients were included in the study. Overall, VAP incidence was 23.8% and AbVAP, 11.4%. Previous hospitalization of another patient with Acinetobacter baumannii infection was the only independent risk factor for AbVAP (OR (95% CI) 12.016 (2.282-19.521) P < 0.001). ICU stay (25 ± 17 versus 12 ± 9  P < 0.001), the incidence of other infections (OR (95% CI) 9.485 (1.640-10.466) P = 0.002) (urinary tract infection, catheter related infection, and bacteremia), or sepsis (OR (95% CI) 10.400 (3.749-10.466) P < 0.001) were significantly increased in patients with AbVAP compared to patients without VAP; no difference was found with respect to ICU mortality.

CONCLUSION

ICU admission or the hospitalization of patients infected by Acinetobacter baumannii increases the risk of AbVAP by subsequent patients.