Comparison of clinical characteristics of bacteremia from Elizabethkingia meningoseptica and other carbapenem-resistant,non-fermenting Gram-negative bacilli at a tertiary medical center

Background

Acquired carbapenem resistance among non-fermenting Gram-negative bacilli (NFGNB), such as Pseudomonas aeruginosa and Acinetobacter calcoaceticus-Acinetobacter baumannii complex (ACB complex), is a serious problem in nosocomial infections. We previously reported that patients infected with the intrinsically carbapenem-resistant Elizabethkingia meningoseptica were associated with high mortality. However, little information is available regarding the clinical outcome of E. meningoseptica bacteremia when compared to that of other carbapenem-resistant NFGNB.

Changing trend of antimicrobial resistance among gram-negative bacilli isolated from lower respiratory tract of ICU patients: A 5-year study

Background:

Lower respiratory tract infections (LRTIs) are the most frequent infections among patients in intensive care units (ICUs).

Aim:

To track the resistance rate among the causative agents causing LRTI in the ICU patients.

Design and Settings:

This is a retrospective study done in a tertiary care hospital.

Materials and Methods:

Transtracheal or bronchial aspirates from 2776 patients admitted to the ICU were cultured and identified, and antibiotic sensitivity was performed by standard methods.

Results:

Of 2776 specimens, 1233 (44.41%) isolates were recovered, of which 1123 (91.07%) were gram-negative bacilli (GNB) and 110 (8.92%) were gram-positive organisms. From 2004 to 2009, Pseudomonas aeruginosa remained the most common pathogen. In phase I, high level of resistance (79–98%) was observed against all GNB. During phase II increasing trend in resistance to cephalosporins and declining trend in resistance to aminoglycosides against most GNB were observed. Multidrug resistance (resistance to three or more than three drugs) was observed in 83% of total isolates.

Conclusions:

Gram-negative organisms are the predominant pathogens causing LRTI in ICU. The increasing trend of resistance to cephalosporins and carbapenems in gram-negative organisms is very disturbing. Judicious use of antimicrobial agents is essential to prevent the emergence of multidrug-resistant bacteria in the ICU.     

Carbapenem resistant Gram-negative bacteremia in an Indian intensive care unit: A review of the clinical profile and treatment outcome of 50 patients

Background:

Growing antimicrobial resistance and limited therapeutic options to treat carbapenem-resistant bacteremia prompted us to evaluate the clinical outcomes associated with healthcare-associated bacteremia.

Methods:

This was a retrospective observational study of carbapenem-resistant Gram-negative bacteremia performed at a tertiary care facility in Chennai, India between May 2011 and May 2012.

Results:

In our study, patients had mean 11.76 days of intensive care unit (ICU) care and mean time to onset of bacteremia was 6.4 days after admission. The commonest organism was Klebsiella pneumoniae (44%). Patients with combination treatment had lower mortality (44.8%) compared with colistin monotherapy (66.6%); (P = 0.35).

Conclusion:

Carbapenem resistant bacteremia is a late onset infection in patients with antibiotic exposure in the ICU and carries a 30 days mortality of 60%; K. pneumoniae is the most common organism at our center. Two drug combinations appear to carry a lower mortality compared with monotherapy.     

Antimicrobial resistance patterns among aerobic Gram-negative bacilli isolated from patients in intensive care units: results of a multicenter study in Russia

Objective: To determine the antimicrobial resistance patterns among aerobic Gram-negative bacilli isolated from patients in intensive care units (ICUs) in different parts of Russia.
Methods: During 1995–96, 10 Russian hospitals from different geographic areas were asked to submit 100 consecutive Gram-negative isolates from patients with ICU-acquired infections. Minimal inhibitory concentrations (MICs) of 12 antimicrobials were determined by Etest and results were interpreted according to National Committee for Clinical Laboratory Standards (NCCLS) guidelines.
Results: In total, 1005 non-duplicate strains were obtained from 863 patients. The most common species were Pseudomonas aeruginosa (28.8%), Escherichia coli (21.4%), Klebsiella pneumoniae (16.7%), Proteus mirabilis (9.7%), Enterobacter spp. (8.2%) and Acinetobacter spp. (7.7%). High levels of resistance were seen to second- and third-generation cephalosporins, ureidopenicillins, β-lactam/β-lactamase inhibitor combinations and gentamicin. The most active agents were imipenem (no resistance in Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterobacter spp. and Acinetobacter spp., 7% resistance in Pseudomonas aeruginosa ), amikacin (7% resistance in Pseudomonas aeruginosa and Acinetobacter spp., 4% in Enterobacter spp., 1% in Escherichia coli and Proteus mirabilis, no resistance in Klebsiella pneumoniae ) and ciprofloxacin (15% resistance in Pseudomonas aeruginosa, 5% in Enterobacter spp. and Proteus mirabilis, 2% in Klebsiella pneumoniae, 1% in Escherichia coli ).
Conclusions: Second- and third-generation cephalosporins, ureidopenicillins, β-lactam/β-lactamase inhibitor combinations and gentamicin cannot be considered as reliable drugs for empirical monotherapy for aerobic Gram-negative infections in ICUs in Russia.     

Detection of cross-transmission of multiresistant Gram-negative bacilli and Staphylococcus aureus in adult intensive care units by routine typing of clinical isolates

Objective: To determine the potential of laboratory services in identifying cross-transmission of multiresistant Gram-negative bacilli (MR GNB) and Staphylococcus aureus in adult intensive care units by routine typing of clinical isolates.
Methods: Over a 12-month period, isolates with indistinguishable PCR fingerprints were traced back to the source patients and their epidemiologic relationships were investigated. Possible episodes of cross-transmission were ascertained, and the validity of antibiograms in identifying the same cluster assessed.
Results: Of 3503 specimens received by the microbiological laboratory during 5372 patient days, 1295 cultures showed bacterial growth. Of these, 132 were primary isolates of MR GNB and 92 were primary isolates of S. aureus . Thirty-two MR GNB isolates (24%) shared fingerprints with one or more other isolates. Indistinguishable isolates from epidemiologically related patients suggested 17 episodes of cross-transmission. The positive and negative predictive values of antibiogram-based identification of these episodes were 19% and 72% respectively. S aureus displayed limited genetic diversity. The two most frequent genotypes contained 19 and 16 isolates, of which the majority appeared to be epidemiologically unrelated.
Conclusions: Endemic transmission of MR GNB occurs mainly between two patients and remains unrecognized by conventional laboratory investigation. Rapid genetic typing methods identify patients involved in cross-transmission and give an insight into the population dynamics of MR GNB on adult intensive care units.     

Antibiotic strategies and clinical outcomes in critically ill patients with pneumonia caused by carbapenem-resistant Acinetobacter baumannii

ObjectivesThis study aimed to investigate antibiotic prescribing patterns and effectiveness of different anti-carbapenem-resistant Acinetobacter baumannii (CRAB) strategies for CRAB pneumonia.MethodsWe conducted a multicentre, retrospective study in three hospitals. During 2010–2015, adult ICU patients with CRAB pneumonia treated with at least one antimicrobial agent covering the CRAB isolate in vitro for more than 2 days were included. We used multivariate logistic regression to analyse the associations of anti-CRAB strategies with ICU mortality and other clinical outcomes.ResultsAmong 238 patients with CRAB pneumonia, tigecycline monotherapy (84, 35.3%) was the most common antibiotic strategy, followed by tigecycline with colistin (43, 18.1%), colistin monotherapy (34, 14.3%), colistin combination without tigecycline (33, 13.9%), tigecycline combination without colistin (32, 13.4%), and sulbactam-based therapy without tigecycline and colistin (12, 5.0%). In multivariate analysis, tigecycline-based therapy was associated with higher ICU mortality than non-tigecycline therapy (adjusted OR 2.30, 95% CI 1.19–4.46). There was no difference between colistin-based therapy and non-colistin therapy. Compared with tigecycline monotherapy, colistin monotherapy was associated with lower ICU mortality (aOR 0.30, 95% CI 0.10–0.88). Treatment failure analyses showed similar trends. Tigecycline-based therapy was associated with higher treatment failure rate than non-tigecycline therapy (aOR 2.51, 95% CI 1.39–4.54), whereas colistin-based therapy was associated with lower treatment failure rate than non-colistin-based therapy (aOR 0.48, 95% CI 0.27–0.86).ConclusionsTigecycline was commonly prescribed for CRAB pneumonia. However, tigecycline-based therapy was associated with higher ICU mortality and treatment failure. Our study suggests that colistin monotherapy may be a better antibiotic strategy for CRAB pneumonia.     

An audit of characteristics and outcomes in adult intensive care patients following tracheostomy

Background:

Tracheostomies are commonly performed on critically ill patients requiring prolonged mechanical ventilation. The purpose of this study was to review our experience with surgical and percutaneous tracheostomies and identify factors affecting outcome.

Materials and Methods:

Patients who underwent tracheostomy between January 1999 and June 2008 were identified on the basis of Diagnostic Related Group coding and the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, Australian Modification procedural code. The primary endpoint was in-hospital mortality. Contingency tables were generated for clinical variables and a chi-squared test was used to determine significance.

Results:

One hundred and sixty-eight patients underwent tracheostomy between January 1999 and 30 June 2008. In-hospital mortality was 22.6%. The probability of death was found to be independent of timing of tracheostomy, technique used (percutaneous vs. surgical), number of failed extubations and obesity. On univariate analysis, the null hypothesis of independence was rejected for age on admission (P = 0.014), diagnosis of sepsis (P = 0.0008) or cardiac arrest (P = 0.0016), Acute Physiology and Chronic Health Evaluation II score (P = 0.0319) and the Australasian Outcomes Research Tool for Intensive Care calculated risk of death (P = 0.0432).

Conclusion:

Although a number of patient factors are associated with worse outcome, tracheostomy appears to be a relatively safe technique in the Intensive Care Unit population.     

Impact of prior pulmonary tuberculosis in treatment outcomes of HCAP and CAP patients in intensive care units

Background/purpose

It is controversial whether healthcare-associated pneumonia (HCAP) belongs to a unique clinical entity or it shares common characteristics with community-acquired pneumonia (CAP). The impact of prior pulmonary tuberculosis (PTB) in clinical presentation and treatment outcome of ICU-admitted CAP and HCAP patients also remains unknown.

Ignorance of pre-ED healthcare setting is a factor leading to inappropriate initial antibiotic treatment of sepsis in ED and poor outcomes in ICU

ObjectivesAppropriate initial antibiotic therapy is critical for successfully treating sepsis. In the emergency department (ED), clinicians often rely on septic symptoms to guide empirical therapy. The aim of this study was to investigate whether history of contacting pre-ED healthcare setting is easy to be neglected and whether the patients received more inappropriate initial antibiotic therapy and developed poorer outcomes.MethodsSeptic patients (n = 453) admitted from ED to the intensive care unit (ICU) between 2014 and 2017 were retrospectively selected. Appropriate antibiotic treatment or not was determined by checking whether the selected antibiotics can effectively eradicate the bacteria identified. Various indexes were compared between patients with appropriate and inappropriate initial antibiotic treatments, including septic symptoms (qSOFA scores) in ED, septic-severity change in ICU (SOFA-score ratios), and septic outcomes (APACHE II scores, stay length, 30-day survival probability). These indexes were also compared between pre-ED healthcare and pre-ED community patients.ResultsIn comparison with pre-ED community patients, pre-ED healthcare patients received more inappropriate initial antibiotic treatment in ED, showing poorer outcomes in ICU, including septic severity, stay-lengths in ICU and 30-day survival probabilities. Pre-ED settings is more significant than qSOFA scores to predict the inappropriate initial antibiotic treatment.ConclusionsPre-ED healthcare settings, which are indexes for infection with antibiotic resistant pathogens, are easy to be neglected in the first hour in ED. We suggested that standard operating procedure for getting enough information of pre-ED settings should be incorporated to the 1 h bundle of sepsis guideline.     

Clinical characteristics and treatment outcomes of vancomycin-resistant Enterococcus faecium bacteremia

Background

Vancomycin-resistant Enterococcus faecium (VRE-fm) bacteremia causes significant mortality in hospitalized patients. We sought to investigate clinical characteristics, treatment outcomes, and microbiological eradication associated with VRE-fm bacteremia.

Liver abscesses in adult patients with and without diabetes mellitus: an analysis of the clinical characteristics,features of the causative pathogens,outcomes and predictors of fatality: a report based on a large population,retrospective study in China

In China, there are four types of liver abscesses (LAs) that meet the clinical criteria. Pyogenic liver abscesses (PLAs) and amoebic liver abscesses (ALAs) are two of the most common types of abscesses, followed by fungal liver abscesses (FLAs) and hydatid secondary liver abscesses (HsLAs). Diabetes mellitus (DM) is associated with the development of PLAs. However, there is a lack of population-based studies that have evaluated the underlying relationship between LAs (mainly PLAs and FLAs) and DM. We conducted a retrospective study based on a large population to identify the potential differences and factors that affect the mortality of PLA patients in DM and non-DM groups. Our results revealed that the prevalence of DM is 44.3% (158/357) in PLA patients and 35.3% (18/51) in FLA patients. Compared with the non-DM patients, statistically significant differences were found in DM patients according to symptomatology, clinical manifestations, laboratory findings, microbiological characteristics, antimicrobial resistance, clinical treatments and outcomes in relation to mortality. In addition, the status of antibiotic resistance to E. coli and K. pneumoniae, which were isolated from the patient samples, is severe in the area in which the study was conducted. Regarding the treatment of PLAs, our study indicated that broad-spectrum antimicrobial therapy and drug combinations should be recommended and initiated before the pathogens are cultured and identified. In the clinic, therapies that combine percutaneous drainage with antibiotics and surgery with antibiotics are the two most useful strategies for treating an LA. These two combined treatments resulted in satisfactory cure rates. In the DM and non-DM groups, the cure rates for percutaneous drainage with antibiotics were 90.3% and 92.0%, respectively, and the cure rates for surgery with antibiotics were 93.9% and 95.2%, respectively.