Macrolide therapy is associated with lower mortality in community-acquired bacteraemic pneumonia

Challenges for a broad international implementation of the current severe community-acquired pneumonia guidelines

Severe community-acquired pneumonia (sCAP) remains one of the leading causes of admission to the intensive care unit, thus consuming a large share of resources and is associated with high mortality rates worldwide. The evidence generated by clinical studies in the last decade was translated into recommendations according to the first published guidelines focusing on severe community-acquired pneumonia. Despite the advances proposed by the present guidelines, several challenges preclude the prompt implementation of these diagnostic and therapeutic measures. The present article discusses the challenges for the broad implementation of the sCAP guidelines and proposes solutions when applicable.

Macrolides for better resolution of community-acquired pneumonia: A global meta-analysis of clinical outcomes with focus on microbial aetiology

OBJECTIVES

This meta-analysis examined the effect of macrolides on resolution of community-acquired pneumonia (CAP) and interpretation of clinical benefit according to microbiology; emphasis is given to data under-reported countries (URCs).

METHODS

This meta-analysis included 47 publications published between 1994 and 2022. Publications were analysed for 30-d mortality (58 759 patients) and resolution of CAP (6465 patients). A separate meta-analysis was done for the prevalence of respiratory pathogens in URCs.

RESULTS

Mortality after 30 d was reduced by the addition of macrolides (odds ratio [OR] 0.65, 95% confidence interval [CI] 0.51-0.82). The OR for CAP resolution when macrolides were added to the treatment regimen was 1.23 (95% CI 1.00-1.52). In the CAP resolution analysis, the most prevalent pathogen was Streptococcus pneumoniae (12.68%; 95% CI 9.36-16.95%). Analysis of the pathogen epidemiology from the URCs included 12 publications. The most prevalent pathogens were S. pneumoniae (24.91%) and Klebsiella pneumoniae (12.90%).

CONCLUSION

The addition of macrolides to the treatment regimen led to 35% relative decrease of 30-d mortality and to 23% relative increase in resolution of CAP.

The Role of Macrolides for the Management of Community-Acquired Pneumonia and Pneumonia by the Novel Coronavirus SARS-CoV-2 (COVID-19): A Position Paper by Four Medical Societies from Greece

In light of the accumulating evidence for survival benefit coming from the use of macrolides for community-acquired pneumonia (CAP), a group of experts from the field of internal medicine and infectious diseases frame a position statement on the use of macrolides for the management of bacterial CAP and for infection by the novel coronavirus (COVID-19). The statement is framed taking into consideration existing publications and own research experience. The main content of this statement is that the combination of one β-lactam and a macrolide should be the first treatment of choice for patients with severe bacterial CAP. Severity is assessed as scoring 2 or more points on the CURB65 scoring system of severity or as pneumonia severity index III to V or C-reactive protein more than 150 mg/l; the suggested macrolide is either azithromycin or clarithromycin. The experts also suggest that in COVID-19 pneumonia, the combination of one β-lactam and a macrolide should be reserved only when there is strong suspicion of bacterial co-infection.

Pneumococal community-acquired pneumonia in the intensive care unit: Azithromycin remains protective despite macrolide resistance

BACKGROUND

Streptococcus pneumoniae (SP) remains the leading pathogen in community-acquired pneumonia (CAP). Despite the increasing prevalence of macrolide resistance in SP, guidelines recommend the use of macrolides as part of a combination regiment for intensive care unit (ICU) patients with CAP. We sought to describe if macrolide resistance effects outcomes in SP CAP in the ICU and if macrolides remain associated with a mortality advantage in an era of greater resistance.

METHODS

We identified all patients with SP CAP admitted to the ICU between January 2012 and December 2016, and hospital mortality represented the primary endpoint. We recorded markers of acute and chronic disease severity (eg, Charlson score, need for mechanical ventilation and/or vasopressors) along with infection-related variables including the presence of macrolide resistance. We compared subjects treated with azithromycin to those not given this agent.

RESULTS

The cohort included 140 subjects (89.2% on mechanical ventilation, 14.3% crude mortality). Macrolide resistance occurred often (60.8%) and, in univariate analyses, was associated with higher mortality while azithromycin use appeared linked to fewer death. In multivariate analysis controlling for multiple confounders including macrolide resistance and the timeliness and appropriateness of antibiotic therapy, treatment with azithromycin resulted in fewer death (Adjusted odds ratio 0.27, 95% confidence interval: 0.09-0.85, p = 0.024). Macrolide resistance, however, was not independently related to mortality.

CONCLUSIONS

Macrolide resistance appears frequently in SP ICU CAP. The addition of azithromycin to the antibiotic regimen in this scenario is significantly associated with a reduction in in-hospital mortality independent of multiple co-variates.

Characteristics and outcomes among a hospitalized patient cohort with Streptococcus pneumoniae infection

Infection due to Streptococcus pneumoniae (SP) requiring hospitalization is common. However, recent clinical studies describing patient characteristics and outcomes for SP infection in adults requiring hospitalization are lacking. Our goal was to evaluate patient characteristics, contemporary antibiotic resistance, and clinical outcomes among hospitalized adults with SP infections.A retrospective cohort study was conducted at Barnes-Jewish Hospital (1350 beds) in St. Louis, Missouri, USA for years 2012 through 2016. During the study period, 358 hospitalized adults, excluding those with meningitis, were identified with SP infection. Forty-four patients (12.3%) died within 30 days of the identification of their infection. Among these infections, 99 (27.7%) were assessed to be hospital-acquired and 259 (72.3%) were community-onset infections. The majority of infections involved the respiratory tract (88.5%). Azithromycin resistance was the most common antibiotic resistance at 51.4%, followed by enteral penicillin resistance (45.3%), trimethoprim-sulfamethoxazole (34.1%), second-generation cephalosporin (cefuroxime) (30.7%), and meropenem (22.6%). There were 70 isolates (19.6%) classified as multidrug resistant. Independent predictors of hospital mortality included increasing weight in 1-kilogram increments (adjusted odds ratio [AOR], 1.02; 95% CI, 1.01 - 1.02; P = .048), increasing Charlson Comorbidity Index scores (AOR, 1.31; 95% CI, 1.21 - 1.42; P = .001), and the presence of septic shock (AOR, 3.89; 95% CI, 2.31 - 6.57; P = .009). The median [interquartile range] hospital length of stay was 8.1 days [4.5 days, 16.8 days].Hospitalized patients with infection attributed to SP have significant 30-day mortality and use of hospital resources. Antibiotic resistance is common among isolates associated with infection. Determinants of mortality are primarily severity of illness, underlying comorbidities and increasing patient weight. Efforts to improve the treatment and prevention of SP infections are needed.

Antibiotic Use and Respiratory Pathogens in Adults With Sickle Cell Disease and Acute Chest Syndrome

Background: Acute chest syndrome (ACS) is an acute complication of sickle cell disease (SCD). Historically, the most common pathogens were Chlamydophila pneumoniae, Mycoplasma pneumoniae, and respiratory syncytial virus. Pediatric patients receiving guideline-adherent therapy experienced fewer ACS-related and all-cause 30-day readmissions compared with those receiving nonadherent therapy. This has not been evaluated in adults. Objectives: The primary objectives were to characterize antibiotic use and pathogens. The secondary objective was to assess the occurrence of readmissions associated with guideline-adherent and clinically appropriate treatment compared with regimens that did not meet those criteria. Methods: A retrospective cohort analysis was conducted for adults with SCD hospitalized between August 1, 2014, and July 31, 2017, with pneumonia (PNA) or ACS. The study was approved by the institutional review board. Results: A total of 139 patients with 255 hospitalizations were reviewed. Among 41 respiratory cultures, 3 organisms were isolated: Cryptococcus neoformans, Pseudomonas aeruginosa, and budding yeast. Respiratory panels were collected on 121 admissions, with 17 positive for 1 virus; all were negative for Chlamydophila pneumoniae and M pneumoniae. There were significantly more ACS-/PNA-related 7-day readmissions from patients on guideline-adherent regimens compared with nonadherent regimens (3.7% vs 0%; P = 0.04). Conclusion and Relevance: These findings challenge existing knowledge regarding the most common pathogens in adults with SCD with ACS or PNA. Routine inclusion of a macrolide may not be necessary. Future studies focused on pathogen characterization with standardized assessment are necessary to determine appropriate empirical therapy in this population.

Effect of Combined β-Lactam/Macrolide Therapy on Mortality According to the Microbial Etiology and Inflammatory Status of Patients With Community-Acquired Pneumonia

BACKGROUND

Antibiotic combinations that include macrolides have shown lower mortality rates than β-lactams in monotherapy or combined with fluoroquinolones in patients with community-acquired pneumonia (CAP). However, this effect has not been studied according to the levels of C-reactive protein in CAP with identified microbial cause. In patients with CAP and known microbial cause we aimed to evaluate 30-day mortality of a β-lactam plus macrolide (BL + M) compared with a fluoroquinolone alone or with a β-lactam (FQ ± BL).

METHODS

We analyzed a prospective observational cohort of patients with CAP admitted to the Hospital Clinic of Barcelona between 1996 and 2016. We included only patients with known microbial cause.

RESULTS

Of 1,715 patients (29%) with known etiology, a total of 932 patients (54%) received BL + M. Despite lower crude mortality in the BL + M group in the overall population (BL + M, 5% vs FQ ± BL, 8%; P = .015), after adjustment by a propensity score and baseline characteristics, the combination of BL + M had a protective effect on mortality only in patients with high inflammatory response (C-reactive protein, > 15 mg/dL) and pneumococcal CAP (adjusted OR, 0.28; 95% CI, 0.09-0.93). No benefits on mortality were observed for the population without high inflammatory response and pneumococcal CAP or with other etiologies.

CONCLUSIONS

The combination of a β-lactam with a macrolide was associated with decreased mortality in patients with pneumococcal CAP and in patients with high systemic inflammatory response. When both factors occurred together, BL + M was protective for mortality in the multivariate analysis.

Moving Past the Routine Use of Macrolides-Reviewing the Role of Combination Therapy in Community-Acquired Pneumonia

PURPOSE OF REVIEW

Despite advances in diagnostic microbiology and sepsis management, community-acquired pneumonia (CAP) remains a significant cause of morbidity and mortality. Current recommendations regarding the use of beta-lactams in combination with macrolides published in clinical practice guidelines are variable and based on low-quality evidence that is frequently retrospective, observational, and heterogeneous in nature. While population-based studies have historically suggested improved clinical outcomes with the routine use of macrolide combination therapy in hospitalized patients with CAP, emerging evidence from recent randomized controlled trials has challenged this practice. In this article, we discuss the historical rationale and current evidence for combination macrolide therapy in the management of CAP.

RECENT FINDINGS

Recent randomized controlled trials have assessed the non-inferiority of beta-lactam monotherapy compared to beta-lactam/macrolide combination therapy in adult patients hospitalized with CAP. Beta-lactam monotherapy was associated with equivalent clinical outcomes in patients with mild to moderate CAP. Patients with severe CAP managed with beta-lactam monotherapy have demonstrated worse clinical outcomes when compared to patients treated with combination therapy. In addition, previous beta-lactam exposure prior to hospitalization has not been shown to negatively impact outcomes in patients managed with beta-lactam monotherapy in the hospital. Current evidence supports the use of beta-lactam monotherapy in adult patients hospitalized with mild to moderate CAP. While existing evidence supports the use of combination therapy in patients with severe pneumonia, further large-scale randomized controlled trials are urgently needed to clarify the role of combination therapy in this population.