Duration and cessation of antimicrobial treatment

An investigation of the effects of procalcitonin testing on antimicrobial prescribing in respiratory tract infections in an Irish university hospital setting: a feasibility study

BACKGROUND

Diagnostic uncertainty and a high prevalence of viral infections present unique challenges for antimicrobial prescribing for respiratory tract infections (RTIs). Procalcitonin (PCT) has been shown to support prescribing decisions and reduce antimicrobial use safely in patients with RTIs, but recent study results have been variable.

METHODS

We conducted a feasibility study of the introduction of PCT testing in patients admitted to hospital with a lower RTI to determine if PCT testing is an effective and worthwhile intervention to introduce to support the existing antimicrobial stewardship (AMS) programme and safely decrease antimicrobial prescribing in patients admitted with RTIs.

RESULTS

A total of 79 patients were randomized to the intervention PCT-guided treatment group and 40 patients to the standard care respiratory control group. The addition of PCT testing led to a significant decrease in duration of antimicrobial prescriptions (mean 6.8 versus 8.9 days, P = 0.012) and decreased length of hospital stay (median 7 versus 8 days, P = 0.009) between the PCT and respiratory control group. PCT did not demonstrate a significant reduction in antimicrobial consumption when measured as DDDs and days of therapy.

CONCLUSIONS

PCT testing had a positive effect on antimicrobial prescribing during this feasibility study. The successful implementation of PCT testing in a randomized controlled trial requires an ongoing comprehensive education programme, greater integration into the AMS programme and delivery of PCT results in a timely manner. This feasibility study has shown that a larger randomized controlled trial would be beneficial to further explore the positive aspects of these findings.

Risk Factors for Multidrug-Resistant Acinetobacter baumannii Infections in a Mass Burn Casualty Incident

They investigated the risk factors of multidrug-resistant Acinetobacter baumannii infections in 33 burn patients in a mass burn casualty. The independent variables included sex, burn size, vancomycin, ampicillin/sulbactam, cefazolin, meropenem, third-/fourth-generation cephalosporin, the number of classes of antibiotic used, and the number of days of antibiotic use. Multidrug-resistant A. baumannii infection was the outcome variable. Logistic regressions and structural equation model were used for statistical analysis. The average age was 21.7 years (range, 17-32 years; M = 11 [33%], F = 22 [67%]; mean burn area, 42% of the total body surface area; study period, June 28, 2015 to July 31, 2015). The incidence of infection was 39% (n = 13/33). For every percent increase in burn size, the odds of developing A. baumannii infections increased by 1.1 (P < .05). Similarly, the odds increased by 2.5 in every number increase in the classes of antibiotic used, by 1.2 in everyday increase in the days of antibiotic used, and by 12 in patients treated with vancomycin (P < .05). The correlations of these risk factors were demonstrated in a hypothetical structural equation model (P-value of chi-squared test > .05 and root mean square error of approximation < 0.05) in which burn size was the fundamental risk factor of multidrug-resistant A. baumannii infections. The model did not predict the emergence of multidrug-resistant A. baumannii infections. Conclusively, the risks of multidrug-resistant A. baumannii infections in burns are correlated with burn size, the number of classes of antibiotic used, the number of days of antibiotic use, and the prior use of vancomycin.

Procalcitonin-Guided Treatment on Duration of Antibiotic Therapy and Cost in Septic Patients (PRODA): a Multi-Center Randomized Controlled Trial

BACKGROUND

The objective of this study was to establish the efficacy and safety of procalcitonin (PCT)-guided antibiotic discontinuation in critically ill patients with sepsis in a country with a high prevalence of antimicrobial resistance and a national health insurance system.

METHODS

In a multi-center randomized controlled trial, patients were randomly assigned to a PCT group (stopping antibiotics based on a predefined cut-off range of PCT) or a control group. The primary end-point was antibiotic duration. We also performed a cost-minimization analysis of PCT-guided antibiotic discontinuation.

RESULTS

The two groups (23 in the PCT group and 29 in the control group) had similar demographic and clinical characteristics except for need for renal replacement therapy on ICU admission (46% vs. 14%; P = 0.010). In the per-protocol analysis, the median duration of antibiotic treatment for sepsis was 4 days shorter in the PCT group than the control group (8 days; interquartile range [IQR], 6-10 days vs. 14 days; IQR, 12-21 days; P = 0.001). However, main secondary outcomes, such as clinical cure, 28-day mortality, hospital mortality, and ICU and hospital stays were not different between the two groups. In cost evaluation, PCT-guided therapy decreased antibiotic costs by USD 30 (USD 241 in the PCT group vs. USD 270 in the control group). The results of the intention-to-treat analysis were similar to those obtained for the per-protocol analysis.

CONCLUSION

PCT-guided antibiotic discontinuation in critically ill patients with sepsis could reduce the duration of antibiotic use and its costs with no apparent adverse outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02202941.

The Pharmacoeconomic Aspects of Antibiotic Stewardship Programs

Optimal antimicrobial therapy must take into account the key factors in antibiotic selection, that is, spectrum, tissue penetration, resistance potential, safety profile, and relative cost-effectiveness. The least expensive drug is usually accompanied by other concerns, such as high resistance potential, poor side effect profile, pharmacokinetic properties that limit penetration into target tissue (site of infection), and/or suboptimal activity against the presumed/known pathogen. It is false economy to preferentially select the least expensive antibiotics solely because of its acquisition cost. Therapeutic failure and hidden costs may make an apparently less expensive antibiotic most costly in the end.

Overview of systematic reviews assessing the evidence for shorter versus longer duration antibiotic treatment for bacterial infections in secondary care

Our objective was to assess the clinical effectiveness of shorter versus longer duration antibiotics for treatment of bacterial infections in adults and children in secondary care settings, using the evidence from published systematic reviews. We conducted electronic searches in MEDLINE, Embase, Cochrane, and Cinahl. Our primary outcome was clinical resolution. The quality of included reviews was assessed using the AMSTAR criteria, and the quality of the evidence was rated using the GRADE criteria. We included 6 systematic reviews (n = 3,162). Four reviews were rated high quality, and two of moderate quality. In adults, there was no difference between shorter versus longer duration in clinical resolution rates for peritonitis (RR 1.03, 95% CI 0.98 to 1.09, I² = 0%), ventilator-associated pneumonia (RR 0.93; 95% CI 0.81 to 1.08, I² = 24%), or acute pyelonephritis and septic UTI (clinical failure: RR 1.00, 95% CI 0.46 to 2.18). The quality of the evidence was very low to moderate. In children, there was no difference in clinical resolution rates for pneumonia (RR 0.98, 95% CI 0.91 to 1.04, I² = 48%), pyelonephritis (RR 0.95, 95% CI 0.88 to 1.04) and confirmed bacterial meningitis (RR 1.02, 95% CI 0.93 to 1.11, I² = 0%). The quality of the evidence was low to moderate. In conclusion, there is currently a limited body of evidence to clearly assess the clinical benefits of shorter versus longer duration antibiotics in secondary care. High quality trials assessing strategies to shorten antibiotic treatment duration for bacterial infections in secondary care settings should now be a priority.

Comparing the Outcomes of Adults With Enterobacteriaceae Bacteremia Receiving Short-Course Versus Prolonged-Course Antibiotic Therapy in a Multicenter, Propensity Score-Matched Cohort

Background

The recommended duration of antibiotic treatment for Enterobacteriaceae bloodstream infections is 7-14 days. We compared the outcomes of patients receiving short-course (6-10 days) vs prolonged-course (11-16 days) antibiotic therapy for Enterobacteriaceae bacteremia.

Methods

A retrospective cohort study was conducted at 3 medical centers and included patients with monomicrobial Enterobacteriaceae bacteremia treated with in vitro active therapy in the range of 6-16 days between 2008 and 2014. 1:1 nearest neighbor propensity score matching without replacement was performed prior to regression analysis to estimate the risk of all-cause mortality within 30 days after the end of antibiotic treatment comparing patients in the 2 treatment groups. Secondary outcomes included recurrent bloodstream infections, Clostridium difficile infections (CDI), and the emergence of multidrug-resistant gram-negative (MDRGN) bacteria, all within 30 days after the end of antibiotic therapy.

Results

There were 385 well-balanced matched pairs. The median duration of therapy in the short-course group and prolonged-course group was 8 days (interquartile range [IQR], 7-9 days) and 15 days (IQR, 13-15 days), respectively. No difference in mortality between the treatment groups was observed (adjusted hazard ratio [aHR], 1.00; 95% confidence interval [CI], .62-1.63). The odds of recurrent bloodstream infections and CDI were also similar. There was a trend toward a protective effect of short-course antibiotic therapy on the emergence of MDRGN bacteria (odds ratio, 0.59; 95% CI, .32-1.09; P = .09).

Conclusions

Short courses of antibiotic therapy yield similar clinical outcomes as prolonged courses of antibiotic therapy for Enterobacteriaceae bacteremia, and may protect against subsequent MDRGN bacteria.

Basis for selecting optimum antibiotic regimens for secondary peritonitis

Adequate management of severely ill patients with secondary peritonitis requires supportive therapy of organ dysfunction, source control of infection and antimicrobial therapy. Since secondary peritonitis is polymicrobial, appropriate empiric therapy requires combination therapy in order to achieve the needed coverage for both common and more unusual organisms. This article reviews etiological agents, resistance mechanisms and their prevalence, how and when to cover them and guidelines for treatment in the literature. Local surveillances are the basis for the selection of compounds in antibiotic regimens, which should be further adapted to the increasing number of patients with risk factors for resistance (clinical setting, comorbidities, previous antibiotic treatments, previous colonization, severity…). Inadequate antimicrobial regimens are strongly associated with unfavorable outcomes. Awareness of resistance epidemiology and of clinical consequences of inadequate therapy against resistant bacteria is crucial for clinicians treating secondary peritonitis, with delicate balance between optimization of empirical therapy (improving outcomes) and antimicrobial overuse (increasing resistance emergence).

Impact of antibiotic exposure on occurrence of nosocomial carbapenem-resistant Acinetobacter baumannii infection: a case control study

Carbapenem-resistant Acinetobacter baumannii (CRAB) infection is one of the most important healthcare associated diseases worldwide. Although antibiotic use is recognized as a risk factor for CRAB infection, the impact of antibiotic class and length of use on CRAB infection is still unclear. A case-control study was conducted in adult intensive care units and general wards of Songklanagarind Hospital, a tertiary-care hospital in southern Thailand, to investigate the effect of different antibiotic exposure and the duration of use on the risk of developing CRAB infection. Cases were defined as patients with carbapenem-susceptible A. baumannii (CSAB) or CRAB infection. Controls were randomly selected from patients and matched 1:1 with cases using ward and date of admission. Multinomial logistic regression was used to compute relative risk ratios (RRR) and 95% confidence intervals (CI) for CRAB infection. Of 197 cases with A. baumannii infection, there were 139 with CRAB infection and 58 with CSAB infection. Compared to the control group, use of fluoroquinolones, broad-spectrum cephalosporins and carbapenems for more than three days increased the risk of CRAB infection with RRR (95% CI) of 81.2 (38.1-862.7), 31.3 (9.9-98.7) and 112.1 (7.1-1770.6), respectively. The RRR (95% CI) for one to three day treatment of fluoroquinolones, broad-spectrum cephalosporins and carbapenems were 5.4 (0.8-38.7), 6.2 (0.1-353.2) and 63.3 (15.6-256.9), respectively. Long-term use of certain antibiotics and even short term use of carbapenems increased the risk of CRAB infection. In this setting, use of these antibiotics, especially carbapenems, should be limited to reduce CRAB infection.

Intravenous antibiotic durations for common bacterial infections in children: when is enough enough?

Durations of intravenous antibiotic therapy for bacterial infections in hospitalized children sometimes extend well beyond clinical recovery and are often the primary determinants of length of stay. These durations, however, are not always based on solid evidence. Moreover, fixed durations are invariant to important individual factors. We review guidelines and the available evidence for durations of intravenous antibiotic therapy for meningitis, bacteremia, urinary tract infection, and osteomyelitis, conditions where intravenous antibiotics often extend beyond resolution of clinical symptoms. We propose a framework for the duration of therapy that is intended to serve as a guide when standards of care are either nonexistent, dated, conflicting, or contrary to evidence from published studies. This framework incorporates patient-centered factors such as severity of infection, response to therapy, ease of intravenous access, harms and costs of ongoing intravenous treatment, and family preferences.