Endemic extended-spectrum beta-lactamase-producing Klebsiella pneumoniae at an intensive care unit: risk factors for colonization and infection

Epidemiology of extended-spectrum β-lactamase-producing Enterobacterales infection in kidney transplant recipients

BACKGROUND

Extended-spectrum b-lactamase (ESBL)-producing gram-negative bacilli (ESBL-GNB) are the most important pathogenic bacteria infecting kidney transplant patients. Kidney transplantation has been shown to be a risk factor for nosocomial ESBL-GNB bacteremia. The aims of this study were to describe the epidemiology of ESBL-GNB acquisition and to identify factors associated with ESBL-GNB infection in kidney transplant recipients, including pretransplant ESBL-GNB fecal carriage.

METHODS

A prospective study of patients undergoing kidney transplantation at Ramathibodi Hospital from March 1, 2019-November 30, 2020 was conducted. During this period, 66 patients who underwent kidney transplantation. Perianal swab cultures and urine cultures for ESBL-GNB were obtained from all subjects upon admission for transplantation and on Days 3, 7, 14 and 21 after surgery to determine the prevalence, incidence, and duration of admission before acquisition of the organisms.

RESULTS

Of the 66 patients undergoing kidney transplantation, 18 preoperative perianal swabs were detected to be positive for ESBL-GNB upon admission, representing 27.3% of the cases. The in-hospital perianal swab tests showed a significant increase to 96.8% positive ESBL-GNB cultures at the end of week 3. Approximately one-fourth (27.8%) of patients who acquired ESBL-GNB developed a postoperative symptomatic infection. The infection occurred in 13% of such patients who were not ESBL positive at first. These infections included urinary tract infections (20 cases, [30%], of which 55% were due to ESBL-GNB) and bloodstream infections (13 cases; of which 9 [69.2%] were due to ESBL-GNB). E. coli was the most common pathogen. Previous exposure to antibiotics, including surgical prophylaxis, underlying disease, duration of indwelling urinary catheters and ureteric stents, as well as other operative factors were not found to be significantly associated with the acquisition of ESBL-producing organisms in this dataset.

CONCLUSIONS

ESBL carriage may be a risk factor for the development of bacteremia and other serious infections among kidney transplant recipients, although a statistically significant difference could not be demonstrated owing to the small size of the sample. The high rate of ESBL acquisition suggests that more stringent infection prevention and control efforts are needed.

Extraintestinal Foodborne Pathogens

In general, foodborne diseases present themselves with gastrointestinal symptoms caused by bacterial, viral, and parasitic pathogens well established to be foodborne. These pathogens are also associated with extraintestinal clinical manifestations. Recent studies have suggested that Escherichia coli and Klebsiella pneumoniae, which both cause common extraintestinal infections such as urinary tract and bloodstream infections, may also be foodborne. The resolution and separation of these organisms into pathotypes versus commensals by modern genotyping methods have led to the identification of key lineages of these organisms causing outbreaks of extraintestinal infections. These epidemiologic observations suggested common- or point-source exposures, such as contaminated food. Here, we describe the spectrum of extraintestinal illnesses caused by recognized enteric pathogens and then review studies that demonstrate the potential role of extraintestinal pathogenic E. coli (ExPEC) and K. pneumoniae as foodborne pathogens. The impact of global food production and distribution systems on the possible foodborne spread of these pathogens is discussed.

Incidence and risk factors for acquired colonization and infection due to extended-spectrum beta-lactamase-producing Gram-negative bacilli: a retrospective analysis in three ICUs with low multidrug resistance rate

The purpose of this study is to assess risk factors for the acquisition of extended-spectrum β-lactamase-producing Gram-negative bacilli (ESBL-GNB) colonization and infection (AI) in ICUs with low ESBL-GNB prevalence rate. We conducted a retrospective observational study in three ICUs in Bretagne, France. All patients admitted from January 2016 to September 2017 with a length of stay of 2 days or more were included. Universal screening for ESBL-GNB colonization was performed in all participating ICUs. Of the 3250 included patients, 131 (4.0%) were colonized at admission, 59 acquired colonization while hospitalized (1.9%; 95% CI [1.5–2.5%]), and 15 (0.5%; 95% CI [0.3–0.8%]) acquired ESBL-GNB infections. In the case of infection, the specificity and the negative predictive values of preexistent colonization for the ESBL-GNB etiology were 93.2% [91.5–95.1%] and 95.2% [93.5–97.1%], respectively. Colonization was the main risk factor for ESBL-GNB AI (OR = 9.61; 95% CI [2.86–32.29]; p < 0.001). Antimicrobial susceptibility of non-ESBL-GNB isolates responsible for AI was similar for any non-carbapenem β-lactam (95%) and imipenem (94%). ESBL-GNB AIs were rare in ICUs with low ESBL-GNB prevalence rate. Prior colonization was the main risk factor for subsequent infection. Empirical carbapenem therapy could be avoided in non ESBL-GNB colonized patients with suspected AI.

Outcome of Late-onset Neonatal Sepsis at a Tertiary Hospital in Oman

Objectives

We sought to determine the prevalence, pattern of causative organisms, and mortality of newborns with culture-proven late-onset sepsis (LOS) and to determine and compare the risk factors linked to late-onset gram-positive and late-onset gram-negative sepsis in Sultan Qaboos University Hospital (SQUH).

Methods

We conducted a cross-sectional retrospective study of data obtained between 1 January 2007 and 31 December 2014 (eight years) from infants in the neonatal intensive care unit (NICU) at SQUH. Infants born in SQUH (inborn) and other institutions (outborn) with positive blood cultures were included in the study.

Results

The total number of live births and admissions during the study period were 26 289 and 3559, respectively. The total number of infants identified with LOS were 125 of whom 69 (55.2%) were gram-positive, 52 (41.6%) were gram-negative, and four (3.2%) were due to Candida species (spp.). The majority of infants (n = 113, 90.4%) were inborn; 69 (55.2%) were males and 56 (44.8%) were females. The prevalence of LOS among inborn admissions was 4.3 per 1000 live births. Most infections occurred in very low birth weight infants (n = 81, 64.8%). Eleven (8.8%) infants died due to gram-negative sepsis. Klebsiella pneumoniae followed by Pseudomonas aeruginosa were the leading cause of death. Maternal intrapartum antibiotics were the only independent risk factor correlating with gram-negative organisms in multivariate analysis (p = 0.003).

Conclusions

LOS poses a burden in the NICU, which could be due to the increasing survival of premature babies. The main contributing organisms to LOS are gram-positive bacteria. Klebsiella spp. is a major cause of mortality in LOS. The use of intrapartum antibiotic prophylaxis in mothers might explain the positive correlation of maternal antibiotics as a risk factor with gram-negative infections.

Is systematic fecal carriage screening of extended-spectrum beta-lactamase-producing Enterobacteriaceae still useful in intensive care unit: a systematic review

BACKGROUND

Extended-spectrum beta-lactamase-producing Enterobacteriaceae (ESBL-E) are disseminating worldwide leading to increased hospital length of stay and mortality in intensive care units (ICU). ESBL-E dissemination was first due to outbreaks in hospital settings which led to the implementation of systematic fecal carriage screening to improve hygiene procedures by contact precautions. ESBLs have since spread in the community, and the relevance of contact precautions is questioned. ESBL-E dissemination led to an overuse of carbapenems triggering the emergence of carbapenem-resistant Enterobacteriaceae. Empirical antimicrobial therapy based on ESBL-E fecal carriage has been proposed but is debated as it could increase the consumption of carbapenems among ESBL-E carriers without any clinical benefit. Finally, selective decontamination among ESBL-E fecal carriers is evoked to decrease the risk for subsequent ESBL-E infection, but its efficacy remains debated. We propose to systematically review the evidence to recommend or not such systematic ESBL-E fecal carriage screening in adult ICU.

METHODS

Every article focusing on ESBL-E and ICU available on the MEDLINE database was assessed. Articles were included if focusing on cross-transmission, efficacy of hygiene procedures, link between ESBL-E colonization and infection or guidance of empirical therapy or selective decontamination efficacy.

RESULTS

Among 330 articles referenced on PubMed, 39 abstracts were selected for full-text assessment and 25 studies were included. Systematic screening of ESBL-E fecal carriage to guide contact precautions do not seem to decrease the rate of ESBL-E cross-transmission. It has a very good negative predictive value for subsequent ESBL-E infections but a positive predictive value between 40 and 50% and so does not help to spare carbapenems. Cessation of ESBL-E carriage systematic screening could decrease the use of carbapenems in ICU without any clinical harm. Nevertheless, further studies are needed to validate these results from monocentric before-after study. Selective decontamination strategy applied to ESBL-E fecal carriers could be helpful, but available data are conflicting.

CONCLUSION

Current knowledge lacks of high-quality evidence to strongly recommend in favor of or against a systematic ESBL-E fecal carriage screening policy for ICU patients in a non-outbreak situation. Further evaluation of selective decontamination or fecal microbiota transplantation among ESBL-E fecal carriers is needed.

Colonization With Antimicrobial-Resistant Gram-Negative Bacilli at Neonatal Intensive Care Unit Discharge

BACKGROUND

The epidemiology of the colonization of infants with antimicrobial-resistant Gram-negative bacilli (GNB) at discharge from the neonatal intensive care unit (NICU) is not well understood.

METHODS

A multicenter study in which rectal surveillance samples for culture were obtained at NICU discharge from infants hospitalized ≥14 days was performed. Factors associated with colonization with GNB resistant to gentamicin, third/fourth-generation cephalosporin agents, or carbapenem agents were assessed by using a fixed-effects model.

RESULTS

Of these infants, 9% (119 of 1320) were colonized with ≥1 antimicrobial-resistant GNB. Prolonged treatment (≥10 days) with meropenem or third/fourth-generation cephalosporin agents or treatment for ≥5 days with a β-lactam/β-lactamase combination agent were associated with an increased risk of colonization with GNB resistant to gentamicin. Surgery and ≥5 days of treatment with third/fourth-generation cephalosporin agents, a β-lactam/β-lactamase combination agent, or metronidazole were associated with an increased risk of colonization with GNB resistant to third/fourth-generation cephalosporin agents. Female sex and prolonged treatment (≥10 days) with meropenem were associated with colonization with GNB resistant to carbapenem agents.

CONCLUSIONS

Prolonged treatment with broad-spectrum antibiotics was associated with the colonization of infants with antimicrobial-resistant GNB within 7 days of NICU discharge. These findings suggest the potential for dissemination of resistant GNB from colonized infants to other NICUs, the community, or pediatric long-term care facilities. Antimicrobial stewardship efforts aimed at improving appropriate antibiotic use could have a beneficial effect on the emergence of antimicrobial-resistant GNB in the NICU population.

ICU Acquisition Rate, Risk Factors, and Clinical Significance of Digestive Tract Colonization With Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae: A Systematic Review and Meta-Analysis

OBJECTIVE

To evaluate the acquisition rate, identify risk factors, and estimate the risk for subsequent infection, associated with the colonization of the digestive tract with extended-spectrum beta-lactamase-producing Enterobacteriaceae during ICU-hospitalization.

DATA SOURCES

PubMed, EMBASE, and reference lists of all eligible articles.

STUDY SELECTION

Included studies provided data on ICU-acquired colonization with extended-spectrum beta-lactamase-producing Enterobacteriaceae in previously noncolonized and noninfected patients and used the double disk synergy test for extended-spectrum beta-lactamase-producing Enterobacteriaceae phenotypic confirmation. Studies reporting extended-spectrum beta-lactamase-producing Enterobacteriaceae outbreaks or data on pediatric population were excluded.

DATA EXTRACTION

Two authors independently assessed study eligibility and performed data extraction.

DATA SYNTHESIS

Thirteen studies (with 15,045 ICUs-patients) were evaluated using a random-effect model and a meta-regression analysis. The acquisition rate of digestive tract colonization during ICU stay was 7% (95% CI, 5-10) and it varies from 3% (95% CI, 2-4) and 4% (95% CI, 2-6) in the Americas and Europe to 21% (95% CI, 9-35) in the Western Pacific region. Previous hospitalization (risk ratio, 1.57 [95% CI, 1.07-2.31]) or antibiotic use (risk ratio, 1.65 [95% CI, 1.15-2.37]) and exposure to beta-lactams/beta-lactamase inhibitors (risk ratio, 1.78 [95% CI, 1.24-2.56]) and carbapenems (risk ratio, 2.13 [95% CI, 1.49-3.06]) during the ICU stay were independent risk factors for ICU-acquired colonization. Importantly, colonized patients were more likely to develop an extended-spectrum beta-lactamase-producing Enterobacteriaceae infection (risk ratio, 49.62 [95% CI, 20.42-120.58]). The sensitivity and specificity of prior colonization to predict subsequent extended-spectrum beta-lactamase-producing Enterobacteriaceae infection were 95.1% (95% CI, 54.7-99.7) and 89.2% (95% CI, 77.2-95.3), respectively.

CONCLUSIONS

The ICU acquisition rate of extended-spectrum beta-lactamase-producing Enterobacteriaceae ranged from 5% to 10%. Previous use of beta-lactam/beta-lactamase or carbapenems and recent hospitalization were independent risk factors for extended-spectrum beta-lactamase-producing Enterobacteriaceae colonization, and colonization was associated with significantly higher frequency of extended-spectrum beta-lactamase-producing Enterobacteriaceae subsequent infection and increased mortality.

Clinical and Molecular Epidemiology of Extended-Spectrum Beta-Lactamase-Producing Klebsiella spp.: A Systematic Review and Meta-Analyses

Healthcare-related infections caused by extended-spectrum beta-lactamase (ESBL)-producing Klebsiella spp. are of major concern. To control transmission, deep understanding of the transmission mechanisms is needed. This systematic review aimed to identify risk factors and sources, clonal relatedness using molecular techniques, and the most effective control strategies for ESBL-producing Klebsiella spp. A systematic search of PubMed, Embase, and Outbreak Database was performed. We identified 2771 articles from November 25th, 1960 until April 7th, 2014 of which 148 were included in the systematic review and 23 in a random-effects meta-analysis study. The random-effects meta-analyses showed that underlying disease or condition (odds ratio [OR] = 6.25; 95% confidence interval [CI] = 2.85 to 13.66) generated the highest pooled estimate. ESBL-producing Klebsiella spp. were spread through person-to-person contact and via sources in the environment; we identified both monoclonal and polyclonal presence. Multi-faceted interventions are needed to prevent transmission of ESBL-producing Klebsiella spp.

Prospective Evaluation of Colonization with Extended-Spectrum β-Lactamase (ESBL)–Producing Enterobacteriaceae Among Patients at Hospital Admission and of Subsequent Colonization with ESBL-Producing Enterobacteriaceae Among Patients During Hospitalization

Objective.

To determine the rates of and risk factors for carriage and acquisition of extended-spectrum (β-lactamase (ESBL)-producing Enterobacteriaceae during hospitalization.

Design.

Cohort study.

Setting.

Shaare Zedek Medical Center, a 550-bed teaching hospital.

Methods.

During a 5-month period (February 1-June 30, 2004), 167 (8%) of 1,985 newly admitted general medical patients were enrolled in our study. Nasal, oropharyngeal, and rectal swab specimens were obtained at admission and every 2-3 days until hospital discharge or death. Enterobacteriaceae isolates were tested for ESBL, andStaphylococcus aureusisolates were tested for methicillin resistance.

Results.

Of the 167 patients enrolled in our study, 15 (9%) were identified as nasal carriers of methicillin-resistantS. aureus(MRSA) at admission, and 13 (8%) were rectal carriers of ESBL-producing Enterobacteriaceae at admission. Univariate risk factors for rectal carriage of ESBL-producing Enterobacteriaceae included female sex (odds ratio [OR], 11 [95% confidence interval {CI}, 1.4—238];P< .05), nursing home residence (OR, 6.9 [95% CI, 1.8-27];P< .01), recent antibiotic treatment (OR, 9.8 [95% CI, 1.7-74];P< .05), and concomitant nasal carriage of MRSA and/or ESBL-producing Enterobacteriaceae (OR, 5.8 [95% CI, 1.2-26];P< .01). Multivariate risk factors were female sex and recent antibiotic treatment. During hospitalization, 35 (21%) of 167 patients had acquired rectal carriage of ESBL-producing Enterobacteriaceae (P= .002, for trend analysis). Of the 12 patients who were still in the hospital 2 weeks after admission, 4 (33%) were carriers of ESBL-producing Enterobacteriaceae. Univariate risk factors for acquisition included an age of older than 65 years (P< .005), nursing home residence (OR 2.6, [95% CI, 0.98-2.6]), impaired cognition (OR, 4.8 [95% CI, 1.9-12]), recent antibiotic treatment (OR, 2.7 [95% CI, 0.9-8.3]), respiratory assistance (OR, 4.2 [95% CI, 1.2-14]), and prolonged hospitalization. Multivariate risk factors were an age of older than 65 years and broad-spectrum antibiotic therapy.

Conclusions.

Rectal carriage of ESBL-producing Enterobacteriaceae occurred in 13 (8%) of 167 patients at admission to the medical departments of our hospital and in 4 (33%) of 12 patients still remaining in our hospital after 2 weeks.

Risk factors for tracheobronchial acquisition of resistant Gram-negative bacterial pathogens in mechanically ventilated ICU patients

The aim of this study was to identify risk factors for tracheobronchial acquisition with the most common resistant Gram-negative bacteria in the intensive care unit (ICU) during the first week after intubation and mechanical ventilation. Tracheobronchial and oropharyngeal cultures were obtained at admission, after 48 hours, and after 7 days of mechanical ventilation. Patient characteristics, interventions, and antibiotic usage were recorded. Among 71 eligible patients with two negative bronchial cultures for resistant Gram-negative bacteria (at admission and within 48 hours), 41 (58%) acquired bronchial resistant Gram-negative bacteria by day 7. Acquisition strongly correlated with presence of the same pathogens in the oropharynx: Acinetobacter baumannii [odds ratio (OR) = 20·2, 95% confidence interval (CI): 5·5-73·6], Klebsiella pneumoniae (OR = 8·0, 95% CI: 1·9-33·6), and Pseudomonas aeruginosa (OR = 27, 95%: CI 2·7-273). Bronchial acquisition with resistant K. pneumoniae also was associated with chronic liver disease (OR = 3·9, 95% CI: 1·0-15·3), treatment with aminoglycosides (OR = 4·9, 95% CI: 1·4-18·2), tigecycline (OR = 4·9, 95% CI: 1·4-18·2), and linezolid (OR = 3·9, 95% CI: 1·1-15·0). In multivariate analysis, treatment with tigecycline and chronic liver disease were independently associated with bronchial resistant K. pneumoniae acquisition. Our results show a high incidence of tracheobronchial acquisition with resistant Gram-negative microorganisms in the bronchial tree of newly intubated patients. Oropharynx colonization with the same pathogens and specific antibiotics use were independent risk factors.

Extended-spectrum β lactamase-producing gram-negative bacteria: clinical profile and outcome in a neonatal intensive care unit

BACKGROUND & AIMS

Multidrug-resistant extended-spectrum 3 lactamase-producing bacteria (ESBL) have emerged as a common problem globally. However, data regarding clinical profile and outcome in neonates infected with ESBL-producing gram-negative bacteria are sparse.

METHODS

A retrospective study was undertaken of all neonates admitted between April 2002 and May 2003 to the neonatal intensive care unit, Safdarjang Hospital, New Delhi who had blood cultures positive for gram-negative bacteria. The clinical profile and outcome in each patient was obtained from the case notes. The mortality and morbidity of the ESBL (cases) and non-ESBL groups were compared. Data were analysed using the chi(2) and Student's t-tests.

RESULTS

There were 75 cases of gram-negative septicaemia, 46 newborns (61.3%) were infected with ESBL-producing strains and 63 case records were available. ESBL production was associated with prematurity (24/38 vs 9/25, p=0.03), prolonged rupture of membranes (14/38 vs 2/25, p=0.01) and previous antibiotic administration to the infant (15/38 vs 1/25, p=0.002). Fifty per cent of infants with early-onset sepsis and 82.1% with late-onset sepsis were infected with ESBL strains. Newborns with ESBL sepsis were more likely to manifest persistent thermal instability (13/38 vs 3/25, p=0.04) and pre-feed gastric aspirates (18/38 vs 3/25, p=0.004). More than 90% of ESBL isolates were susceptible to carbapenems, cefperazone-sulbactam and piperacillin-tazobactam. The mean length of nursery stay (15.8 vs 10.7, p=0.02) and mortality (23.6 vs 4.0%, p= 0.07) were higher in the ESBL group and onset of feeds was delayed (7.6 vs 3.9 days, p=0.007) in this group.

CONCLUSIONS

Isolation of ESBL in cases of early-onset sepsis indicates that ESBL producers might have percolated into the community. Early suspicion of ESBL-producing isolates in cases of neonatal sepsis can facilitate prompt institution of appropriate empirical therapy and lead to an improved outcome.

Pretransplant fecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae and infection after liver transplant, France

Bacterial infection after liver transplant is fairly common, mostly because liver transplant patients are severely ill and the surgery is very complex. Adding to the seriousness of this situation is that some bacteria are resistant to many antimicrobial drugs. However, treating all infections as drug resistant would lead to even more drug resistance, so only patients at highest risk should receive the most powerful drugs. But who is at highest risk? A recent study in France screened fecal samples of liver transplant candidates and found that post-operative infections were most likely for those patients who already had certain bacteria in their feces before surgery. Thus, fecal screening for those multiresistant bacteria should be considered for all liver transplant candidates so that if post-operative infection develops, those at high risk can receive the most specific drugs right away.

Potential role of active surveillance in the control of a hospital-wide outbreak of carbapenem-resistant Klebsiella pneumoniae infection

BACKGROUND

The recent emergence of carbapenem resistance among Enterobacteriaceae is a major threat for hospitalized patients, and effective strategies are needed.

OBJECTIVE

To assess the effect of an intensified intervention, which included active surveillance, on the incidence of infection with carbapenem-resistant Klebsiella pneumoniae.

SETTING

Sheba Medical Center, a 1,600-bed tertiary care teaching hospital in Tel Hashomer, Israel.

DESIGN

Quasi-experimental study.

METHODS

The medical records of all the patients who acquired a carbapenem-resistant K. pneumoniae infection during 2006 were reviewed. An intensified intervention was initiated in May 2007. In addition to contact precautions, active surveillance was initiated in high-risk units. The incidence of clinical carbapenem-resistant K. pneumoniae infection over time was measured, and interrupted time-series analysis was performed.

RESULTS

The incidence of clinical carbapenem-resistant K. pneumoniae infection increased 6.42-fold from the first quarter of 2006 up to the initiation of the intervention. In 2006, of the 120 patients whose clinical microbiologic culture results were positive for carbapenem-resistant K. pneumoniae, 67 (56%) developed a nosocomial infection. During the intervention period, the rate of carbapenem-resistant K. pneumoniae rectal colonization was 9%. Of the 390 patients with carbapenem-resistant K. pneumoniae colonization or infection, 204 (52%) were identified by screening cultures. There were a total of 12,391 days of contact precautions, and of these, 4,713 (38%) were added as a result of active surveillance. After initiation of infection control measures, we observed a significant decrease in the incidence of carbapenem-resistant K. pneumoniae infection.

CONCLUSIONS

The use of active surveillance and contact precautions, as part of a multifactorial intervention, may be an effective strategy to decrease rates of nosocomial transmission of carbapenem-resistant K. pneumoniae colonization or infection.

Emergence of resistant Klebsiella pneumoniae in the intestinal tract during successful treatment of Klebsiella pneumoniae lung infection in rats

Antibiotic treatment of lung infections may lead to the emergence of resistance in the gut flora. Appropriate dosing regimens could mitigate this adverse effect. In gnotobiotic rats harboring intestinal Escherichia coli and Enterococcus faecium populations, a lung infection by Klebsiella pneumoniae was instigated with two different sizes of inoculum to represent an early or a late initiation of antibiotic treatment. The rats were treated with marbofloxacin, an expanded-spectrum fluoroquinolone, by a single-shot administration or a fractionated regimen over 4 days. Intestinal bacterial populations were monitored during and after treatment. At the infection site, bacterial cure without any selection of resistance was observed. Whatever the dosage regimen, fluoroquinolone treatment had a transient negative impact on the E. coli gut population but not on that of E. faecium. The intestinal flora was colonized by the pathogenic lung bacteria, and there was the emergence of intestine-resistant K. pneumoniae, occurring more often in animals treated with a single marbofloxacin dose than with the fractionated dose. Bacterial cure without resistance selection at the infection site with fluoroquinolone treatment can be linked to colonization of the digestive tract by targeted pulmonary bacteria, followed by the emergence of resistance.