Carbapenem vs. non-carbapenem antibiotics for ventilator-associated pneumonia: A systematic review with meta-analysis

BACKGROUND

Carbapenem is recommended as one of the first-line regimens for ventilator-associated pneumonia (VAP), but no recent systematic review has fully investigated its efficacy. This systematic review aims to evaluate the efficacy of carbapenem compared with non-carbapenem for VAP treatment.

METHODS

We performed a systematic review and meta-analysis of studies comparing the efficacy and the safety between carbapenem and non-carbapenem with activity to Pseudomonas aeruginosa in the treatment for VAP. The main outcome was mortality, and the additional outcomes were the clinical cure of pneumonia, length of intensive care unit stay, recurrence, adverse effects, and the development of resistant bacteria. This study was conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Of the initial 1,730 publications, 9 randomized control trials were enrolled. In the meta-analysis, no difference was observed between the carbapenem and non-carbapenem regimens in improving mortality (odds ratio, 0.83; 95 % confidence interval (CI) 0.67-1.02). While the carbapenem regimen was superior to the non-carbapenem regimen in studies reporting the resolution of pneumonia (odds ratio, 1.09; 95 % CI 1.01-1.17), the effectiveness of carbapenem treatment was not evident in studies assessing the other outcomes.

CONCLUSIONS

Carbapenem might have no superiority in survival when treating VAP. Moreover, non-carbapenem antibiotics with activities to P. aeruginosa have a potential option to avoid inducing carbapenem-resistant pathogens.

Efficacy of cefmetazole in immunocompetent patients with uncomplicated colonic diverticulitis: A propensity score matching analysis

INTRODUCTION

The incidence of colonic diverticulitis is increasing in Japan. Although antimicrobial chemotherapy is a treatment option, Japanese guidelines for diverticulosis do not recommend any antibiotic in particular and antibiotic selection is left to the discretion of the prescribing physician, who often selects antibiotics with anti-pseudomonal activity. Therefore, this study compared the efficacy of cefmetazole (CMZ) with that of tazobactam/piperacillin (TAZ/PIPC) in hospitalized Japanese immunocompetent patients with uncomplicated colonic diverticulitis.

PATIENTS AND METHODS

This retrospective study included Japanese immunocompetent patients hospitalized for colonic diverticulitis between April 2019 and March 2022. Participants were divided into the CMZ and TAZ/PIPC groups. After propensity score matching, the intergroup differences in clinical outcomes, including adverse events, mortality, and re-admission rate, were ascertained.

RESULTS

During the study period, 142 Japanese patients were hospitalized with community-onset colonic diverticulitis; 124 of these patients were immunocompetent. Of the 124 patients, 42 were excluded, and the CMZ and TAZ/PIPC groups comprised 62 and 20 patients, respectively. After propensity score matching, there were 16 patients in each group. There was no significant intergroup difference in the mortality and re-admission rates; however, the incidence of liver dysfunction was significantly higher (p = 0.018) in the TAZ/PIPC group.

CONCLUSION

In patients with colonic diverticulitis, CMZ therapy should be selected because of the adequate clinical outcomes and lower incidence of adverse events, as this would reduce broad-spectrum antibiotic use and minimize antibiotic-resistant bacteria.

Low utilization of vancomycin in febrile neutropenia: real-world evidence from 4 Brazilian centers

PURPOSE

The prompt initiation of a betalactam antibiotic in febrile neutropenic patients is considered standard of care, while the empiric use of vancomycin is recommended by guidelines in specific situations, with a low level of evidence. The objective of this study was to assess the utilization of vancomycin in the management of febrile neutropenia within four Brazilian medical centers that implemented more stringent criteria for its administration.

METHODS

A comprehensive retrospective analysis was performed encompassing all instances of febrile neutropenia observed during the period from 2013 to 2019. The primary focus was to identify the reasons for initiating vancomycin therapy.

RESULTS

A total of 536 consecutive episodes of febrile neutropenia were documented, involving 384 patients with a median age of 52 years (range 18-86). Chemotherapy preceded febrile neutropenia in 59.7% of cases, while 40.3% occurred after hematopoietic stem cell transplantation. The most prevalent underlying diseases were acute myeloid leukemia (26.5%) and non-Hodgkin's lymphoma (22%). According to international guidelines, vancomycin should have been initiated at the onset of fever in 145 episodes (27%); however, it was administered in only 27 cases (5.0%). Three episodes were associated with Staphylococcus aureus bacteremia, two of which were methicillin resistant. The 15-day and 30-day mortality rates were 5.0% and 9.9%, respectively.

CONCLUSIONS

The results of this study underscore the notably low utilization rate of vancomycin in cases of febrile neutropenia, despite clear indications outlined in established guidelines. These findings emphasize the importance of carefully implementing guideline recommendations, considering local epidemiological factors, especially when the strength of recommendation is weak.

Empiric antimicrobial therapy in the intensive care unit based on the risk of multidrug-resistant bacterial infection: a single-centre case‒control study of blood culture results in Japan

BACKGROUND

Infections and sepsis are the leading causes of death in intensive care units (ICUs). Antimicrobial agent selection is challenging because the intervention is directly related to the outcome, and the problem of antimicrobial resistance (AMR) must be considered. Therefore, in this study, we aimed to clarify the epidemiological data and examine whether the detection rate of multidrug-resistant (MDR) bacteria differed depending on the presence or absence of the risk of MDR bacterial infections to establish guidance regarding the choice of antimicrobial therapy for ICU patients.

METHODS

This retrospective case‒control study was performed in a single ICU in Japan. Patients admitted to the ICU who underwent blood culture (BC) analysis were considered for inclusion in this study; patients were at risk of MDR bacterial infections, and controls were not. The primary outcome measure was the detection rate of MDR bacteria in BCs collected from patients and controls. The secondary outcome measure was the selection rate of anti-Pseudomonas and anti-methicillin-resistant Staphylococcus aureus (MRSA) drugs for patients and controls.

RESULTS

Among the 1,730 patients admitted to the ICU during the study period, BCs were obtained from 186 patients, and 173 samples were finally included in the analysis (n = 129 cases; n = 44 controls). No MDR bacteria or Pseudomonas aeruginosa were detected in the controls (14 (11%) vs. 0 (0%)) (P = 0.014) However, there was no difference in empiric antimicrobials, including anti-MRSA (30 (23%) vs. 12 (27%)) (P = 0.592) and anti-Pseudomonas aeruginosa (61 (47%) vs. 16 (36%)) (P = 0.208) drugs, that were administered to the two groups.

CONCLUSIONS

Even in critically ill patients in the ICU, MDR bacteria are unlikely to be detected in patients without the risk of MDR bacterial infections. Therefore, for such patients, a strategy of starting empiric narrow-spectrum antimicrobial therapy rather than empiric broad-spectrum therapy should be considered. This strategy, in conjunction with daily updates of clinical and epidemiological data at each facility, will promote the appropriate use of antimicrobials and reduce the emergence of MDR bacteria in the ICU.

TRIAL REGISTRATION

None.

Empiric versus culture-based antibiotic therapy for UTIs in menopausal women

PURPOSE

To assess the benefits and risks associated with empiric prescription of antibiotic therapy for treatment of a urinary tract infection (UTI).

METHODS

Following IRB approval menopausal women presenting with a symptomatic UTI to a single urology clinic were prospectively assigned to one of the two treatment groups based on day of presentation: culture-based treatment (CB) (Monday, Tuesday, Wednesday) or empiric treatment (ET) (Thursday, Friday) and started on nitrofurantoin (NF) pending culture results. Both groups were contacted at 7 and 14 days following treatment. Side effects and answers to a standardized questionnaire (UTISA) were recorded. Success was defined as a total UTISA score < 3. Any NF retreatment, use of another antibiotic therapy, or extension of the original antibiotic course was considered treatment failures.

RESULTS

From July 2020 to March 2022, 65 women with 80 UTI events were included in the study, with CB treatment used for 60 UTIs and ET used for 23 UTIs. At 7 days after start of treatment, questionnaire failure rate was 44% (20/45) for the CB group and 16% (3/19) for the ET group (P = 0.076). At 14 days following start of treatment, questionnaire failure rate was 31% (13/42) for the CB group and 17% (3/18) for the ET group (P = 0.3). In the ET group, 11% of cultures were found to be resistant to NF.

CONCLUSION

Outcomes for the empiric treatment of uncomplicated UTI with NF at both 7 and 14 days are not significantly different than outcomes with culture-based treatment.

Utilising cumulative antibiogram data to enhance antibiotic stewardship capacity in the Cape Coast Teaching Hospital, Ghana

BACKGROUND

Antimicrobial resistance (AMR) is a major public health challenge with its impact felt disproportionately in Western Sub-Saharan Africa. Routine microbiology investigations serve as a rich source of AMR monitoring and surveillance data. Geographical variations in susceptibility patterns necessitate regional and institutional tracking of resistance patterns to aid in tailored Antimicrobial Stewardship (AMS) interventions to improve antibiotic use in such settings. This study focused on developing a cumulative antibiogram of bacterial isolates from clinical samples at the Cape Coast Teaching Hospital (CCTH). This was ultimately to improve AMS by guiding empiric therapy.

METHODS

A hospital-based longitudinal study involving standard microbiological procedures was conducted from 1st January to 31st December 2020. Isolates from routine diagnostic aerobic cultures were identified by colony morphology, Gram staining, and conventional biochemical tests. Isolates were subjected to antibiotic susceptibility testing using Kirby-Bauer disc diffusion. Inhibitory zone diameters were interpreted per the Clinical and Laboratory Standards Institute guidelines and were entered and analysed on the WHONET software using the "first isolate only" principle.

RESULTS

Overall, low to moderate susceptibility was observed in most pathogen-antibiotic combinations analysed in the study. Amikacin showed the highest susceptibility (86%, n = 537/626) against all Gram-negatives with ampicillin exhibiting the lowest (6%, n = 27/480). Among the Gram-positives, the highest susceptibilities were exhibited by gentamicin (78%, n = 124/159), with clindamycin having the lowest susceptibility (27%, n = 41/154). Among the Gram-negatives, 66% (n = 426/648) of the isolates were identified phenotypically as potential extended-spectrum beta-lactamase producers. Multiple multidrug-resistant isolates were also identified among both Gram-positive and Gram-negative isolates. Low to moderate susceptibility was found against first- and second-line antibiotics recommended in the National standard treatment guidelines (NSTG). Laboratory quality management deficiencies and a turnaround time of 3.4 days were the major AMS barriers identified.

CONCLUSIONS

Low to moderate susceptibilities coupled with high rates of phenotypic resistance warrant tailoring NSTGs to fit local contexts within CCTH even after considering the biases in these results. The cumulative antibiogram proved a key AMS programme component after its communication to clinicians and subsequent monitoring of its influence on prescribing indicators. This should be adopted to enhance such programmes across the country.

Antimicrobial susceptibility testing of Staphylococcus aureus isolates from patients at a tertiary hospital in Tehran, Iran, 2018-2019

Background

Staphylococcus aureus, a human skin and mucous membranes colonizer, could opportunistically cause a variety of infectious diseases. Frequently, it is resistant to methicillin (MRSA), and often, co-resistant to many clinically available antibiotics. MRSA is a major burden for healthcare systems and communities all over the world, especially in developing countries. We addressed the issue that more than a decade had passed since the last report about cumulative antibiogram for S. aureus from our center, whereas The Clinical and Laboratory Standards Institute (CLSI) recommends to analyze and report it on an annual basis in order to guide clinicians to select the best initial empiric antimicrobial therapy.

Methods

In a cross-sectional retrospective design, data of culture-proven S. aureus from clinical specimens of hospitalized patients at Imam Khomeini Hospital Complex, Tehran, Iran, were collected from September 2018 to September 2019. Antimicrobial susceptibility testing (AST) had been performed using either Kirby–Bauer disk diffusion or VITEK 2 automated system which is based on minimum inhibitory concentration (MIC). The Chi-squared test was used considering the critical p-value to be ≤ .05.

Results

Among 576 unique isolates, the overall prevalence of MRSA was 37.5%. Patients admitted to the infectious diseases ward and ICUs have a greater chance to have such an isolate. Methicillin resistance was predictive of resistance to most antibiotics: erythromycin (90.9%), clindamycin (85.4% including inducible resistance), gentamicin, cipro-/levo-/moxi-floxacin, trimethoprim–sulfamethoxazole (58.3%), tetracycline, and rifampin. Resistance rate of zero was observed for daptomycin, linezolid, tigecycline, and (roughly) vancomycin. The prevalence of multiple-drug resistant (MDR) isolates was 48.5%.

Conclusions

Although in this study, the prevalence of MRSA was lower than the previous ones from the same hospital, it is still far from the desired rates. Besides, resistance to clindamycin and trimethoprim–sulfamethoxazole were remarkable. So far, vancomycin is the best choice for empiric treatment of MRSA, with linezolid as the second choice. It is advised to avoid prescribing the newer antibacterial agents as long as the older ones are effective to prevent the emergence of MDR species.

"Rationalization of Empiric Antibiotic Therapy" - A Move Towards Preventing Emergence of Resistant Infections

Antimicrobial resistance is a key factor leading to emerging/ re-emerging infections. Rational antimicrobial therapy or antimicrobial stewardship is one of the important interventions to prevent emergence of resistance. Choosing correct empiric therapy is crucial not only to prevent antimicrobial resistance but also to achieve good treatment outcomes. Antimicrobial therapy can be broadly classified as empiric, definitive/ targeted and preventive. It is in choice of empiric therapy that the largest margin of error exists. Paradoxically, empiric therapy is the most commonly employed therapy since microbiologic results are either not available at initiation of treatment or cannot be sent due to logistic reasons or are negative. In the Indian setting, where penetration of microbiologic diagnostic methods in small cities, towns and rural areas is still fairly low, therapy is largely empiric. Choice of empiric therapy is governed by various factors including likely pathogens, antimicrobial resistance, degree of sickness, site of infection and host co-morbidities. These principles can be applied to any clinical syndrome whether it is fever without focus, infections of the respiratory tract, gastrointestinal tract, abdomen, central nervous system, bone and joint, skin and soft tissue, urinary tract as well as neonatal sepsis and healthcare associated infections. Adherence to published guidelines for syndromic management such as that by the Indian Academy of Pediatrics and Indian Council of Medical Research is strongly recommended. One can tailor these guidelines and suggestions made in this article to an individual setting.

A real-world prospective observational study on the efficacy and safety of liposomal amphotericin B in 426 patients with persistent neutropenia and fever

INTRODUCTION

Invasive fungal diseases are crucial causes of morbidity and mortality among patients with febrile neutropenia (FN). Though liposomal amphotericin B (L-AMB) is one of the agents recommended for first-line empirical antifungal therapy in patients with FN, large-scale clinical studies have not been performed in Japan.

METHODS

An open-label prospective multi-center study was carried out to evaluate the safety and efficacy of L-AMB in Japanese patients with FN suspected of having fungal infection.

RESULTS

Of the 426 patients registered, safety and efficacy evaluations were conducted for 424 and 399, respectively. By clinical response criteria using 5 composite endpoints, the response rate was 46.6% (186/399). The response rate by age were 54.5% (child: 30/55), 47.5% (adult: 97/204), 42.1% (elderly: 59/140) respectively. Regarding the composite endpoints, resolution of fever was observed in 61.2% (244/399), no breakthrough fungal infection in 99.0% (395/399), survival for 7 days or longer after the completion of treatment in 83.7% (334/399), no discontinuation of treatment due to toxicity or lack of efficacy in 60.9% (243/399), and successful treatment of any baseline fungal infection in 10/18. Adverse drug reactions (ADRs) developed in 61.1% (259/424), and frequent ADRs were hypokalemia, kidney dysfunction, and liver dysfunction, as previously reported.

CONCLUSIONS

The safety and efficacy profile of L-AMB in Japanese patients with FN suspected of having fungal infection were elucidated for the first time, through the analysis of a large number of cases including pediatric patients under real-world clinical settings collected in this nationwide study.

Using local clinical and microbiological data to develop an institution specific carbapenem-sparing strategy in sepsis: a nested case-control study

Background

From a stewardship perspective it is recommended that antibiotic guidelines are adjusted to the local setting, accounting for the local epidemiology of pathogens. In many settings the prevalence of Gram-negative pathogens with resistance to empiric sepsis therapy is increasing. How and when to escalate standard sepsis therapy to a reserve antimicrobial agent, is a recurrent dilemma. The study objective was to develop decision strategies for empiric sepsis therapy based on local microbiological and clinical data, and estimate the number needed to treat with a carbapenem to avoid mismatch of empiric therapy in one patient (NNTC).

Methods

We performed a nested case control study in patients (> 18 years) with Gram-negative bacteremia in 2013-2016. Cases were defined as patients with Gram-negative bacteremia with in vitro resistance to the combination 2nd generation cephalosporin AND aminoglycoside (C-2GC + AG). Control patients had Gram-negative bacteremia with in vitro susceptibility to cefuroxime AND/OR gentamicin, 1:2 ratio. Univariate and multivariable analysis was performed for demographic and clinical predictors of resistance. The adequacy rates of empiric therapy and the NNTC were estimated for different strategies.

Results

The cohort consisted of 486 episodes of Gram-negative bacteremia in 450 patients. Median age was 66 years (IQR 56-74). In vitro resistance to C-2GC + AG was present in 44 patients (8.8%). Independent predictors for resistance to empiric sepsis therapy were hematologic malignancy (adjusted OR 4.09, 95%CI 1.43-11.62, p < 0.01), previously cultured drug resistant pathogen (adjusted OR 3.72. 95%CI 1.72-8.03, p < 0.01) and antibiotic therapy during the preceding 2 months (adjusted OR 12.5 4.08-38.48, p < 0.01). With risk-based strategies, an adequacy rate of empiric therapy of 95.2-99.3% could be achieved. Compared to treating all patients with a carbapenem, the NNTC could be reduced by 82.8% (95%CI 78.5-87.5%) using the targeted approaches.

Conclusions

A risk-based approach in empiric sepsis therapy has the potential to better target the use of reserve antimicrobial agents aimed at multi-resistant Gram-negative pathogens. A structured evaluation of the expected antimicrobial consumption and antibiotic adequacy rates is essential to be able to weigh the costs and benefits of potential antibiotic strategies and select the most appropriate approach.

Treating invasive aspergillosis in patients with hematologic malignancy: diagnostic-driven approach versus empiric therapies

BACKGROUND

Early antifungal therapy for invasive aspergillosis (IA) has been associated with improved outcome. Traditionally, of empiric antifungal therapy has been used for clinically suspected IA. We compared outcomes of patients with hematologic malignancy and IA who were treated with voriconazole using the diagnostic driven DDA (DDA-Vori) that includes galactomannan testing vs. empiric therapy with a non-voriconazole-containing regimen (EMP-non-Vori) or empiric therapy with voriconazole (EMP-Vori).

METHODS

We retrospectively reviewed the medical records of 342 hematologic malignancy patients diagnosed with proven, or probable IA between July 1993 and February 2016 at our medical center who received at least 7 days of DDA-Vori, EMP-Vori, or EMP-non-Vori. Outcome assessment included response to therapy (clinical and radiographic), all-cause mortality, and IA-attributable mortality.

RESULTS

By multivariate analysis, factors predictive of a favorable response included localized/sinus IA vs. disseminated/pulmonary IA (p <  0.0001), not receiving white blood cell transfusion (p <  0.01), and DDA-Vori vs. EMP-non-Vori (p < 0.0001). In contrast, predictors of mortality within 6 weeks of initiating IA therapy included disseminated/pulmonary infection vs. localized/sinus IA (p < 0.01), not undergoing stem cell transplantation within 1 year before IA (p = 0.01), and EMP-non-Vori vs. DDA-Vori (p < 0.001).

CONCLUSIONS

DDA-Vori was associated with better outcome (response and survival) compared with EMP-non-Vori and with equivalent outcome to EMP-Vori in hematologic malignancy patients. These outcomes associated with the implementation of DDA could lead to a reduction in the unnecessary costs and adverse events associated with the widespread use of empiric therapy.

MRSA colonization status as a predictor of clinical infection: A systematic review and meta-analysis

BACKGROUND

Vancomycin is often used as empiric therapy for methicillin-resistant Staphylococcus aureus (MRSA), but can be associated with clinically important adverse events including renal failure. MRSA colonization swabs are primarily used for infection control; their use as a diagnostic test to inform the decision to add empiric vancomycin therapy has not been well elucidated.

METHODS

We performed a Medline and Embase systematic review for peer-reviewed studies reporting the diagnostic accuracy of using MRSA colonization status to predict MRSA infections. Meta-analysis was performed using Cochrane guidelines. Grey literature was excluded.

FINDINGS

29 studies were included involving 24225 patients. In cases where the pathogen is not known to be S. aureus, specificities were greater than 85% for bacteremia, lower respiratory tract infections, skin and soft tissue infections (SSTI), and all infections pooled together. Sensitivities ranged between 54.0% and 77.5%. In cases where the pathogen is known to be S. aureus, we found studies on bacteremia and SSTI and arrived at pooled estimates of sensitivities ranging between 56.6% and 56.9%, and of specificities greater than 91%. Most importantly, for most infections in settings where the prevalence of MRSA as a causative organism is below 15%, the negative predictive value of a negative MRSA colonization swab exceeds 90%.

INTERPRETATIONS

In settings of low-moderate MRSA prevalence, negative MRSA screening swabs may prevent unnecessary vancomycin use. More research is needed to assess if this strategy can mitigate the cost of screening in areas with a low MRSA colonization rate.

A decision support system for antibiotic prescription based on local cumulative antibiograms

BACKGROUND

Local cumulative antibiograms are useful tools with which to select appropriate empiric or directed therapies when treating infectious diseases at a hospital. However, data represented in traditional antibiograms are static, incomplete and not well adapted to decision-making.

METHODS

We propose a decision support method for empiric antibiotic therapy based on the Number Needed to Fail (NNF) measure. NNF indicates the number of patients that would need to be treated with a specific antibiotic for one to be inadequately treated. We define two new measures, Accumulated Efficacy and Weighted Accumulated Efficacy in order to determine the efficacy of an antibiotic. We carried out two experiments: the first during which there was a suspicion of infection and the patient had empiric therapy, and the second by considering patients with confirmed infection and directed therapy. The study was performed with 15,799 cultures with 356,404 susceptibility tests carried out over a four-year period.

RESULTS

The most efficient empiric antibiotics are Linezolid and Vancomycin for blood samples and Imipenem and Meropenem for urine samples. In both experiments, the efficacies of recommended antibiotics are all significantly greater than the efficacies of the antibiotics actually administered (P < 0.001). The highest efficacy is obtained when considering 2 years of antibiogram data and 80% of the cumulated prevalence of microorganisms.

CONCLUSION

This extensive study on real empiric therapies shows that the proposed method is a valuable alternative to traditional antibiograms as regards developing clinical decision support systems for antimicrobial stewardship.

Comparison of UTI antibiograms stratified by ED patient disposition

OBJECTIVE

Institutional antibiograms guide Emergency Department (ED) clinicians' empiric antibiotic selection. For this study, we created and compared antibiograms of ED patients stratified by disposition (admitted or discharged).

METHODS

We conducted a cross-sectional study at two hospitals for 2014, comparing antibiograms limited to Escherichia coli urinary tract infections. Study-Specific Antibiograms, created for the study, excluded polymicrobial samples and multiple cultures from the same patient. Study-Specific Antibiograms were arranged by patient disposition: admitted (IP-Only) vs discharged from the ED (ED-Only). Antibiogram data were presented as average antibiotic sensitivities with 95% confidence intervals and demographic data as medians with interquartile ranges. Sensitivities between Study-Specific Antibiograms were compared by Fisher's Exact Test, alpha=0.05, 2 tails.

RESULTS

For Hospital A, 13 antibiotics were compared between Study-Specific ED-Only (n=313) vs IP-Only (n=244). We found that sensitivities to all four antibiotics appropriate for empiric outpatient therapy by Infectious Disease Society of America guidelines were significantly (p<0.0001) higher in the ED-Only compared to IP-Only groups: ciprofloxacin 80% (76-90%) vs 60% (53-69%), levofloxacin 81% (77-91%) vs 63% (57-72%), nitrofurantoin 75% (70-84%) vs 51% (44-58%), and trimethoprim/sulfamethoxazole 73% (68-82%) vs 58% (52-67%). For Hospital B, 14 antibiotics were compared between Study-Specific ED-Only (n=256) and IP-Only (n=168). Two out of the five appropriate empiric outpatient antibiotics had significantly (p<0.0001) higher sensitivities for ED-Only compared to IP-Only: ciprofloxacin 87% (83-91%) vs 71% (64-78%) and levofloxacin 86% (82-91%) vs 71% (65-78%).

CONCLUSIONS

We found higher antibiotic sensitivities in ED-Only than the IP-Only Study-Specific Antibiograms. Our Study-Specific Antibiograms offer an alternative guide for antibiotic selection in the ED.

Empiric treatment against invasive fungal diseases in febrile neutropenic patients: a systematic review and network meta-analysis

Background

The most optimal antifungal agent for empiric treatment of invasive fungal diseases (IFDs) in febrile neutropenia is controversial. Our objective was evaluate the relative efficacy of antifungals for all-cause mortality, fungal infection-related mortality and treatment response in this population.

Methods

Pubmed, Embase and Cochrane Library were searched to identify randomized controlled trials (RCTs). Two reviewers performed the quality assessment and extracted data independently. Pairwise meta-analysis and network meta-analysis were conducted to compare the antifungals.

Results

Seventeen RCTs involving 4583 patients were included. Risk of bias of included studies was moderate. Pairwise meta-analysis indicated the treatment response rate of itraconazole was significantly better than conventional amphotericin B (RR = 1.33, 95%CI 1.10–1.61). Network meta-analysis showed that amphotericin B lipid complex, conventional amphotericin B, liposomal amphotericin B, itraconazole and voriconazole had a significantly lower rate of fungal infection-related mortality than no antifungal treatment. Other differences in outcomes among antifungals were not statistically significant. From the rank probability plot, caspofungin appeared to be the most effective agent for all-cause mortality and fungal infection-related mortality, whereas micafungin tended to be superior for treatment response. The results were stable after excluding RCTs with high risk of bias, whereas micafungin had the lowest fungal infection-related mortality.

Conclusions

Our results highlighted the necessity of empiric antifungal treatment and indicates that echinocandins appeared to be the most effective agents for empiric treatment of febrile neutropenic patients based on mortality and treatment response. However, more studies are needed to determine the best antifungal agent for empiric treatment. Our systematic review has been prospectively registered in PROSPERO and the registration number was CRD42015026629.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2263-6) contains supplementary material, which is available to authorized users.

Comparative effectiveness of β-lactam versus vancomycin empiric therapy in patients with methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia

BACKGROUND

Vancomycin may be inferior to β-lactams for the empiric treatment of methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia. We compared empiric β-lactams to vancomycin to assess clinical outcomes in patients with MSSA bacteremia.

METHODS

We conducted a retrospective cohort study of adult inpatients with their first episode of MSSA bacteremia at two tertiary care hospitals in Vancouver, Canada, between 2007 and 2014. Exposure was either empiric β-lactam with or without vancomycin or vancomycin monotherapy. All patients received definitive treatment with cloxacillin or cefazolin. The primary outcome was 28-day mortality. Secondary outcomes were 90-day mortality, duration of bacteremia, and hospital length-of-stay. Outcomes were adjusted using multivariable logistic regression.

RESULTS

Of 669 patients identified, 255 met inclusion criteria (β-lactam = 131, vancomycin = 124). Overall 28-day mortality was 7.06 % (n = 18). There were more cases of infective endocarditis in the β-lactam than in the vancomycin group [24 (18.3 %) vs 12 (9.7 %), p = 0.05]. Adjusted mortality at 28 days was similar between the two groups (OR 0.85; 95 % CI 0.27-2.67). The duration of bacteremia was longer in the vancomycin group (97.1 vs 70.7 h, p = 0.007). Transition to cloxacillin or cefazolin occurred within a median of 68.3 h in the vancomycin group.

CONCLUSIONS

Empiric β-lactams was associated with earlier clearance of bacteremia by a median of 1 day compared to vancomycin. Future prospective studies are needed to confirm our findings.

BRAVO esophageal pH monitoring: more cost-effective than empiric medical therapy for suspected gastroesophageal reflux

INTRODUCTION

Early referral for catheter-based esophageal pH monitoring is more cost-effective than empiric proton-pump inhibitor (PPI) therapy to diagnose gastroesophageal reflux disease (GERD). We hypothesize that BRAVO wireless pH monitoring will also demonstrate substantial cost-savings compared to empiric PPI therapy, given its superior sensitivity and comfort.

METHODS

We reviewed 100 consecutive patients who underwent wireless pH monitoring for suspected GERD at our institution. A cost model and a cost equivalence calculation were generated. Cost-saving analyses were performed for both esophageal and extraesophageal symptoms.

RESULTS

Eighty-seven patients were available for analysis. Median PPI use prior to referral was 215 weeks (range 0-520). Forty-three patients (49 %) had BRAVO results diagnosing GERD; 98 % of these had esophageal symptoms. Patients with negative BRAVO studies had a median of 113 (0-520) weeks of unnecessary PPI therapy. Cost-savings ranged from $1048 to $15,853 per patient, depending on sensitivity (75-95 %), PPI dosage, and brand. Maximum cost-savings occurred in patients with extraesophageal symptoms ($2948-$31,389 per patient). The PPI cost equivalence of BRAVO placement was 36 and 6 weeks for low- and high-dose therapy, respectively.

CONCLUSIONS

BRAVO wireless pH testing is more cost-effective than prolonged empiric medical management for GERD and should be incorporated early in the treatment algorithm.

How to select an antifungal agent in critically ill patients

Fungal infections are common in critically ill patients and are associated with increased morbidity and mortality. Candida spp are the most commonly isolated fungal pathogens. The last 2 decades have seen an increased incidence of fungal infections in critical illness and the emergence of new pathogenic fungal species and also the development of more effective (better bioavailability) and safer (less toxicity, fewer drug interactions) drugs. The distinction between colonization and infection can be difficult, and problems diagnosing infection may delay initiation of antifungal treatment. A number of factors have been identified that can help to distinguish patients at high risk for fungal infection. The antifungal agents that are most frequently used in the intensive care unit are the first- and second-generation azoles and the echinocandins; amphotericin B derivatives (mainly the liposomal agents) are less widely used because of adverse effects. The choice of antifungal agent in critically ill patients will depend on the aim of therapy (prophylaxis, pre-emptive, empiric, definitive), as well as on local epidemiology and specific properties of the drug (antifungal spectrum, efficacy, toxicity, pharmacokinetic/pharmacodynamic properties, cost). In this article we will review all these aspects and propose an algorithm to guide selection of antifungal agents in critically ill patients.

Antimicrobial sensitivity patterns of cerebrospinal fluid (CSF) isolates in Namibia: implications for empirical antibiotic treatment of meningitis

OBJECTIVE

Bacterial meningitis is a medical emergency associated with high mortality rates. Cerebrospinal fluid (CSF) culture is the "gold standard" for diagnosis of meningitis and it is important to establish the susceptibility of the causative microorganism to rationalize treatment. The Namibia Standard Treatment Guidelines (STGs) recommends initiation of empirical antibiotic treatment in patients with signs and symptoms of meningitis after taking a CSF sample for culture and sensitivity. The objective of this study was to assess the antimicrobial sensitivity patterns of microorganisms isolated from CSF to antibiotics commonly used in the empirical treatment of suspected bacterial meningitis in Namibia.

METHODS

This was a cross-sectional descriptive study of routinely collected antibiotic susceptibility data from the Namibia Institute of Pathology (NIP) database. Results of CSF culture and sensitivity from January 1, 2009 to May 31, 2012, from 33 state hospitals throughout Namibia were analysed.

RESULTS

The most common pathogens isolated were Streptococcus species, Neisseria meningitidis, Haemophilus influenzae, Staphylococcus, and Escherichia coli. The common isolates from CSF showed high resistance (34.3% -73.5%) to penicillin. Over one third (34.3%) of Streptococcus were resistance to penicillin which was higher than 24.8% resistance in the United States. Meningococci were susceptible to several antimicrobial agents including penicillin. The sensitivity to cephalosporins remained high for Streptococcus, Neisseria, E. coli and Haemophilus. The highest percentage of resistance to cephalosporins was seen among ESBL K. pneumoniae (n = 7, 71%-100%), other Klebsiella species (n = 7, 28%-80%), and Staphylococcus (n = 36, 25%-40%).

CONCLUSIONS

The common organisms isolated from CSF were Streptococcus Pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Staphylococcus, and E. coli. All common organisms isolated from CSF showed high sensitivity to cephalosporins used in the empirical treatment of meningitis. The resistance of the common isolates to penicillin is high. Most ESBL K. pneumoniae were isolated from CSF samples drawn from neonates and were found to be resistant to the antibiotics recommended in the Namibia STGs. Based on the above findings, it is recommended to use a combination of aminoglycoside and third-generation cephalosporin to treat non-ESBL Klebsiella isolates. Carbapenems (e.g., meropenem) and piperacillin/tazobactam should be considered for treating severely ill patients with suspected ESBL Klebsiella infection. Namibia should have a national antimicrobial resistance surveillance system for early detection of antibiotics that may no longer be effective in treating meningitis and other life-threatening infections due to resistance.