How to choose the duration of antibiotic therapy in patients with pneumonia

An algorithm for PCT-guided antimicrobial therapy: a consensus statement by Japanese experts

In Japan, a national antimicrobial resistance (AMR) action plan was adopted in 2016, advocating a 20% reduction in antibiotic consumption by 2020. However, there is still room for improvement to accomplish this goal. Many randomized controlled trials have reported that procalcitonin (PCT)-guided antimicrobial therapy could help to reduce antibiotic consumption without negative health effects, specifically in acute respiratory infections. In September 2018, some experts in Europe and the USA proposed algorithms for PCT-guided antimicrobial therapy in mild to moderate infection cases outside the ICU and severe cases in the ICU (the international experts consensus). Thereafter, a group of Japanese experts, including specialists in intensive care medicine, emergency medicine, respiratory medicine and infectious diseases, created a modified version of a PCT-guided algorithm (Japanese experts consensus). This modified algorithm was adapted to better fit Japanese medical circumstances, since PCT-guided therapy is not widely used in daily clinical practice in Japan. The Japanese algorithm has three specific characteristics. First, the target patients are limited to only hospitalized ICU or non-ICU patients. Second, pneumonia due to Pseudomonas aeruginosa, Staphylococcus aureus and Legionella species are excluded. Finally, a different timing of PCT follow-up measurement was proposed to meet restrictions of the Japanese medical insurance system. The adapted algorithms has high potential to further improve the safe reduction in antibiotic consumption in Japan, while reducing the spread of AMR pathogens.

International prevalence and risk factors evaluation for drug-resistant Streptococcus pneumoniae pneumonia

OBJECTIVE

Streptococcus pneumoniae is the most frequent bacterial pathogen isolated in subjects with Community-acquired pneumonia (CAP) worldwide. Limited data are available regarding the current global burden and risk factors associated with drug-resistant Streptococcus pneumoniae (DRSP) in CAP subjects. We assessed the multinational prevalence and risk factors for DRSP-CAP in a multinational point-prevalence study.

DESIGN

The prevalence of DRSP-CAP was assessed by identification of DRSP in blood or respiratory samples among adults hospitalized with CAP in 54 countries. Prevalence and risk factors were compared among subjects that had microbiological testing and antibiotic susceptibility data. Multivariate logistic regressions were used to identify risk factors independently associated with DRSP-CAP.

RESULTS

3,193 subjects were included in the study. The global prevalence of DRSP-CAP was 1.3% and continental prevalence rates were 7.0% in Africa, 1.2% in Asia, and 1.0% in South America, Europe, and North America, respectively. Macrolide resistance was most frequently identified in subjects with DRSP-CAP (0.6%) followed by penicillin resistance (0.5%). Subjects in Africa were more likely to have DRSP-CAP (OR: 7.6; 95%CI: 3.34-15.35, p<0.001) when compared to centres representing other continents.

CONCLUSIONS

This multinational point-prevalence study found a low global prevalence of DRSP-CAP that may impact guideline development and antimicrobial policies.

Individualizing duration of antibiotic therapy in community-acquired pneumonia

International experts suggest tailoring antibiotic duration in community-acquired pneumonia (CAP) according to patients' characteristics. We aimed to assess the effectiveness of an individualized approach to antibiotic duration based on time in which CAP patients reach clinical stability during hospitalization. In a multicenter, non-inferiority, randomized, controlled trial hospitalized adult patients with CAP reaching clinical stability within 5 days after hospitalization were randomized to a standard vs. individualized antibiotic duration. In the Individualized group, antibiotics were discontinued 48 h after the patient reached clinical stability, with at least five days of total antibiotic treatment. Early failure within 30 days was the primary composite outcome. 135 patients were randomized to the Standard group and 125 to the Individualized group. The trial was interrupted by the safety committee because of an apparent inferiority of the Individualized group over the Standard treatment: 14 (11.2%) patients in the Individualized group experienced early failure vs. 10 (7.4%) patients in the Standard group, p = 0.200, at the intention-to-treat analysis. 30-day mortality rate was four-time higher in the Individualized group than the Standard group. Shortening antibiotic duration according to patients' characteristics still remains an open question.

Controversies in diagnosis and management of community-acquired pneumonia

Community-acquired pneumonia (CAP) is a common condition; however, it appears to be overdiagnosed. Diagnosing CAP too frequently may be adding to the problems of overuse of antibiotics, such as bacterial resistance in the community and greater costs and complications in individuals. Data support that most patients with non-severe CAP can be treated for 3-5 days; however, most patients with CAP are receiving much longer courses of therapy. Macrolides such as azithromycin have the potential to prolong the QT interval, although large population studies show that this does not appear to result in excess cardiac mortality. CAP is associated with an increase in a variety of cardiac complications, most notably infarctions and worsening cardiac failure, so clinicians should be vigilant for signs and symptoms of these complications, particularly in patients with a history of ischaemic cardiac disease or the presence of cardiac risk factors. Cardiac risk factors should be assessed and managed in patients with CAP over 40 years of age, although there are yet to be data to show that this approach reduces deaths. Corticosteroids may have a slight effect on reducing deaths in patients with severe CAP, but this must be balanced against the significant potential for side effects.

C-reactive protein (CRP) measurement in geriatric patients hospitalized for acute infection

The physiology of inflammatory response is modified by the aging process and is substantially affected by multimorbidity and disability. Infection is the most frequent cause of acute inflammation in both adult and older subjects. C-reactive protein (CRP) is the most used biomarker of inflammation, and a substantial amount of literature has demonstrated its importance and clinical usefulness in adult subjects. However, the clinical significance of serum CRP determination has not been completely clarified in older subjects with acute infection, especially in the light of the age-related rearrangements in immunity and cytokine production. Thus, in the present review, we focus on the existing knowledge about serum CRP level interpretation in geriatric patients hospitalized with acute infection. Our aims were to determine the significance of CRP measurement at hospital admission for establishing a diagnosis of infection and/or a prognosis and to evaluate whether it is indicated to repeat hs-CRP measurements during hospital stay for monitoring disease course and, possibly, guiding the discharge timing. We concluded that CRP dosage at hospital admission is helpful to detect acute infection, and particularly sepsis, in geriatric patients, and that CRP elevation may provide valuable short-term prognostic information. At the current state of art, serial CRP measurements are instead not indicated to monitor disease course and plan hospital discharge in this setting.

Acute bacterial skin and skin structure infections in internal medicine wards: old and new drugs

Skin and soft tissue infections (SSTIs) are a common cause of hospital admission among elderly patients, and traditionally have been divided into complicated and uncomplicated SSTIs. In 2010, the FDA provided a new classification of these infections, and a new category of disease, named acute bacterial skin and skin structure infections (ABSSSIs), has been proposed as an independent clinical entity. ABSSSIs include three entities: cellulitis and erysipelas, wound infections, and major cutaneous abscesses This paper revises the epidemiology of SSTIs and ABSSSIs with regard to etiologies, diagnostic techniques, and clinical presentation in the hospital settings. Particular attention is owed to frail patients with multiple comorbidities and underlying significant disease states, hospitalized on internal medicine wards or residing in nursing homes, who appear to be at increased risk of infection due to multi-drug resistant pathogens and treatment failures. Management of ABSSSIs and SSTIs, including evaluation of the hemodynamic state, surgical intervention and treatment with appropriate antibiotic therapy are extensively discussed.

Non-Intensive Care Unit Acquired Pneumonia: A New Clinical Entity?

Hospital-acquired pneumonia (HAP) is a frequent cause of nosocomial infections, responsible for great morbidity and mortality worldwide. The majority of studies on HAP have been conducted in patients hospitalized in the intensive care unit (ICU), as mechanical ventilation represents a major risk factor for nosocomial pneumonia and specifically for ventilator-associated pneumonia. However, epidemiological data seem to be different between patients acquiring HAP in the ICU vs. general wards, suggesting the importance of identifying non ICU-acquired pneumonia (NIAP) as a clinical distinct entity in terms of both etiology and management. Early detection of NIAP, along with an individualized management, is needed to reduce antibiotic use and side effects, bacterial resistance and mortality. The present article reviews the pathophysiology, diagnosis, treatment and prevention of NIAP.

Treatment of Gram-negative pneumonia in the critical care setting: is the beta-lactam antibiotic backbone broken beyond repair?

Beta-lactam antibiotics form the backbone of treatment for Gram-negative pneumonia in mechanically ventilated patients in the intensive care unit. However, this beta-lactam antibiotic backbone is increasingly under pressure from emerging resistance across all geographical regions, and health-care professionals in many countries are rapidly running out of effective treatment options. Even in regions that currently have only low levels of resistance, the effects of globalization are likely to increase local pressures on the beta-lactam antibiotic backbone in the near future. Therefore, clinicians are increasingly faced with a difficult balancing act: the need to prescribe adequate and appropriate antibiotic therapy while reducing the emergence of resistance and the overuse of antibiotics. In this review, we explore the burden of Gram-negative pneumonia in the critical care setting and the pressure that antibiotic resistance places on current empiric therapy regimens (and the beta-lactam antibiotic backbone) in this patient population. New treatment approaches, such as systemic and inhaled antibiotic alternatives, are on the horizon and are likely to help tackle the rising levels of beta-lactam antibiotic resistance. In the meantime, it is imperative that the beta-lactam antibiotic backbone of currently available antibiotics be supported through stringent antibiotic stewardship programs.

Does High-Dose Antimicrobial Chemotherapy Prevent the Evolution of Resistance?

High-dose chemotherapy has long been advocated as a means of controlling drug resistance in infectious diseases but recent empirical studies have begun to challenge this view. We develop a very general framework for modeling and understanding resistance emergence based on principles from evolutionary biology. We use this framework to show how high-dose chemotherapy engenders opposing evolutionary processes involving the mutational input of resistant strains and their release from ecological competition. Whether such therapy provides the best approach for controlling resistance therefore depends on the relative strengths of these processes. These opposing processes typically lead to a unimodal relationship between drug pressure and resistance emergence. As a result, the optimal drug dose lies at either end of the therapeutic window of clinically acceptable concentrations. We illustrate our findings with a simple model that shows how a seemingly minor change in parameter values can alter the outcome from one where high-dose chemotherapy is optimal to one where using the smallest clinically effective dose is best. A review of the available empirical evidence provides broad support for these general conclusions. Our analysis opens up treatment options not currently considered as resistance management strategies, and it also simplifies the experiments required to determine the drug doses which best retard resistance emergence in patients.

The evolution of antimicrobial resistant pathogens threatens much of modern medicine. For over one hundred years, the advice has been to ‘hit hard’, in the belief that high doses of antimicrobials best contain resistance evolution. We argue that nothing in evolutionary theory supports this as a good rule of thumb in the situations that challenge medicine. We show instead that the only generality is to either use the highest tolerable drug dose or the lowest clinically effective dose; that is, one of the two edges of the therapeutic window. This approach suggests treatment options not currently considered, and simplifies the experiments required to identify the dose that best retards resistance evolution.