Severe community-acquired pneumonia and positive urinary antigen test for S. pneumoniae: amoxicillin is associated with a favourable outcome

Pneumococcal urinary antigen testing for antimicrobial guidance in community-acquired pneumonia: a register-based cohort study

OBJECTIVES

To evaluate the effect of pneumococcal urinary antigen test (UAT) usage on broad-spectrum antibiotic treatment in community-acquired pneumonia (CAP).

METHODS

Patients admitted to 32 Swedish hospitals between 2011-2014 were retrospectively included from the Swedish National Quality Register of CAP. Using propensity score matched data, stratified by CRB-65 score, we studied the effect of performing UAT and of positive test results on treatment with broad-spectrum β-lactam monotherapy (BSBM) and antibiotics with coverage for atypical bacteria compared to narrow-spectrum β-lactam monotherapy (NSBM).

RESULTS

UAT was performed for 4,995/14,590 (34.2%) patients, 603/4,995 (12.1%) of whom had positive test results. At day three, performing UAT was not associated with decreased use of BSBM (OR 1.07, 95% CI 0.94-1.23) but was associated with increased atypical coverage among patients with CRB-65 score 2 (OR 1.47, 95% CI 1.06-2.02). A positive UAT was associated with decreased BSBM use (OR 0.39, 95% CI 0.25-0.60) and decreased atypical coverage (OR 0.25, 95% CI 0.16-0.37), predominantly in non-severe CAP. At day one, performing UAT was associated with atypical coverage among patients with CRB-65 scores 2 (OR 2.60, 95% CI 1.69-3.98) and 3-4 (OR 3.69, 95% CI 1.55-8.79), and a positive test reduced the odds of BSBM treatment among CRB-65 score 3-4 patients (OR 3.49, 95% CI 1.02-12.0).

CONCLUSIONS

Performing UAT had no overall effect on decreasing the use of BSBM treatment by day three of hospitalization, yet non-severely ill patients with positive UAT results were less likely to be treated with BSBM and antibiotics with atypical coverage.

Usefulness of β-lactam and macrolide combination therapy for treating community-acquired pneumonia patients hospitalized in the intensive care unit: Propensity score analysis of a prospective cohort study

INTRODUCTION

Whether β-lactam and macrolide combination therapy reduces mortality in severe community-acquired pneumonia (SCAP) patients hospitalized in the intensive care unit (ICU) is controversial. The aim of the present study was to evaluate the usefulness of β-lactam and macrolide combination therapy for SCAP patients hospitalized in the ICU.

METHODS

A prospective, observational, cohort study of hospitalized pneumonia patients was performed. Hospitalized SCAP patients admitted to the ICU within 24 h between October 2010 and October 2017 were included for analysis. The primary outcome was 30-day mortality, and secondary outcomes were 14-day mortality and ICU mortality. Inverse probability of treatment weighting (IPTW) analysis as a propensity score analysis was used to reduce biases, including six covariates: age, sex, C-reactive protein, albumin, Pneumonia Severity Index score, and APACHE II score.

RESULTS

A total of 78 patients were included, with 48 patients in the non-macrolide-containing β-lactam therapy group and 30 patients in the macrolide combination therapy group. β-lactam and macrolide combination therapy significantly decreased 30-day mortality (16.7% vs. 43.8%; P = 0.015) and 14-day mortality (6.7% vs. 31.3%; P = 0.020), but not ICU mortality (10% vs 27.1%, P = 0.08) compared with non-macrolide-containing β-lactam therapy. After adjusting by IPTW, macrolide combination therapy also decreased 30-day mortality (odds ratio, 0.29; 95%CI, 0.09-0.96; P = 0.04) and 14-day mortality (odds ratio, 0.19; 95%CI, 0.04-0.92; P = 0.04), but not ICU mortality (odds ratio, 0.34; 95%CI, 0.08-1.36; P = 0.13).

CONCLUSIONS

Combination therapy with β-lactam and macrolides significantly improved the prognosis of SCAP patients hospitalized in the ICU compared with a non-macrolide-containing β-lactam regimen.

Risk Factors for Unnecessary Antibiotic Therapy: A Major Role for Clinical Management

BACKGROUND

Assessment of antimicrobial use places an emphasis on therapeutic aspects of infected patients. Our aim was to determine the risk factors for unnecessary antibiotic therapy (UAT).

METHODS

This was a prospective, multicenter study evaluating all curative antibiotic therapies prescribed over 2 consecutive days through the same electronic medical records. Each item that could participate in these prescriptions was collected from the computerized file (reason for hospitalization, comorbid conditions, suspected or definitive diagnosis of infection, microbial analyses). UAT was defined as the recognition of noninfectious sydromes (NIS), nonbacterial infections, use of redundant antimicrobials, and continuation of empirical broad-spectrum antimicrobials.

RESULTS

Four hundred fifty-three antibiotic therapies were analyzed at 17 institutions. An infectious disease was the reason for hospitalization in 201 cases (44%). An unspecified diagnosis of infection was observed in 104 cases (23%). Microbial samples were taken in 296 cases (65%), allowing isolation of a pathogen in 156 cases (53%). Unspecified diagnosis was associated with the absence of a microbial sample compared to patients with a diagnosis: (56/104 [54%] vs 240/349 [69%]; P = .005). A total of 158 NIS were observed (35%). UAT was observed in 169 cases (37%), due to NIS in 106 cases. In multivariate analysis, the modifiable risk factors for UAT were unspecified diagnosis (adjusted odds ratio [AOR], 1.83; 95% confidence interval [CI], 1.04-3.20) and absence of a blood culture (AOR, 5.26; 95% CI, 2.56-10.00).

CONCLUSIONS

UAT is associated with an unspecified diagnosis and the absence of microbial testing. Antimicrobial stewardship programs should focus on diagnostic difficulties and microbial testing, the latter facilitating antibiotic reassessment and therapeutic interruption.

Antibiotic guidelines coupled with selective reporting of antibiograms

OBJECTIVES

We reported the impact of internal guidelines coupled with selective reporting of antibiotic susceptibility tests (srAST) on antibiotic adequacy in healthcare facilities.

METHODS

This prospective study involved clinicians from three clinics with medical and surgical activities employing a full-time infectious disease (ID) specialist. Internal guidelines were updated in 2016. The clinics were working with the same laboratory, which delivered the srAST introduced in March 2017. Two weeks per month over a 6-month period, all isolated bacterial specimens, empirical antibiotic therapies (EAT) and the documented ones were analyzed. An EAT listed in the guidelines and a documented therapy mentioned in the srAST defined their adequacy.

RESULTS

A total of 257 positive bacterial samples were analyzed in 199 patients, for which 106 infections were studied. Of these, 32% were urinary tract infections, 15% were primary bloodstream infections, 11% were bone infections, and 42% were other types of infection. The three main bacteria were Escherichia coli (27%), Staphylococcus aureus (24%), and Enterococcus faecalis (14%). The total number of antibiotic prescriptions was 168, with 75 (45%) EATs and 93 (55%) documented therapies. There were 35/75 (47%) adequate EATs and 86/93 (92%) adequate documented therapies. The ID specialist was not involved in 90/168 (53.5%) prescriptions, of which 43/90 (48%) were adequate, with 21/35 (60%) EATs and 22/86 (25%) documented therapies. There was a statistical correlation between compliance of the EATs with guidelines and of the documented therapy with srAST (p=0.02).

CONCLUSION

Combining internal guidelines and srAST led to a high rate of antibiotic adequacy.

Urinary antigen testing in community-acquired pneumonia in adults: an update

INTRODUCTION

Community-acquired pneumonia (CAP) continues to be a leading cause of hospitalization and mortality worldwide. Streptococcus pneumoniae and Legionella pneumophila remain the major etiological agents and are responsible for a significant proportion of CAP mortality. Among diagnostic tests for CAP, urine antigen detection of S. pneumoniae and L. pneumophila is widely accepted due to the simplicity of collection and the rapidity of the test results. Areas covered: This comprehensive review outlines the urinary antigen tests available, discusses their sensitivity and specificity, and assesses the usefulness of their results as the basis for targeted therapy. Expert commentary: There have been advances in urine antigen detection tests for patients with CAP. New methodologies show greater sensitivity, detect S. pneumoniae and L. pneumophila in a single test, and also detect pneumococcal serotypes. In addition, urine antigen detection tests have shown a high specificity, which means that a positive result practically indicates the causative pathogen of CAP. Therefore, a positive result can lead to a targeted therapy that is likely to improve patient outcomes and reduce the risk of resistance and adverse events. However, well-designed studies are needed to evaluate the usefulness of urine antigen detection tests with regard to clinical outcomes.

Community-acquired pneumonia requiring hospitalization: rational decision making and interpretation of guidelines

PURPOSE OF REVIEW

This review focuses on the evidence base for guideline recommendations on the diagnosis, the optimal choice, timing and duration of empirical antibiotic therapy, and the use of microbiological tests for patients hospitalized with community-acquired pneumonia (CAP): issues for which guidelines are frequently used as a quick reference. Furthermore, we will discuss possibilities for future research in these topics.

RECENT FINDINGS

Many national and international guideline recommendations, even on critical elements of CAP management, are based on low-to-moderate quality evidence.

SUMMARY

The diagnosis and management of CAP has hardly changed for decades. The recommendation to cover atypical pathogens in all hospitalized CAP patients is based on observational studies only and is challenged by two recent trials. The following years, improved diagnostic testing, radiologically by low-dose Computed Tomography or ultrasound and/or microbiologically by point-of-care multiplex PCR, has the potential to largely influence the choice and start of antibiotic therapy in hospitalized CAP patients. Rapid microbiological testing will hopefully improve antibiotic de-escalation or early pathogen-directed therapy, both potent ways of reducing broad-spectrum antibiotic use. Current guideline recommendations on the timing and duration of antibiotic therapy are based on limited evidence, but will be hard to improve.

Cost effectiveness of pneumococcal urinary antigen in Emergency Department: a pragmatic real-life study

Community-acquired pneumonia (CAP) is frequent and can be life-threatening. Streptococcus pneumoniae is the main bacteria involved, and is susceptible to penicillin A. Rapid microbiological diagnosis could then help reduce the antimicrobial spectrum. The pneumococcal urinary antigen (PUA) test is fast and easy to perform, but its impact on antimicrobial prescription and cost-effectiveness in emergency departments (ED) is not well known. We performed a pragmatic real life retrospective study in an adult ED to assess its usefulness: proportion of positive results, impact on antimicrobial prescriptions and cost-effectiveness. Over 3 years (from January 1st 2012 to December 31st 2014), 979 PUA tests were reutilized in our ED among 1224 patients who consulted for CAP; 51 (5.2%) were positive. Among them, 10 led to a modification of the antimicrobial treatment, but only 7 (14.3%) were in accordance with the results. The total cost of a PUA test is 27€. As only 7 PUA tests led to appropriate antimicrobial modification, we deemed that 972 had no impact, and the potential cost savings, if the test had not been used, would have been 26,244 € (972 × 27) during 3 years, that is 8748 € per year. Thus, it seems that the PUA test should not be generally used in the ED considering its low rate of positivity and the difficulties for physicians to adapt antibiotic treatment accordingly. This attitude change in utilization would lead to substantial cost savings.

Cold Chain-Free Storable Hydrogel for Infant-Friendly Oral Delivery of Amoxicillin for the Treatment of Pneumococcal Pneumonia

Pneumonia is the major cause of death in children under five, particularly in developing countries. Antibiotics such as amoxicillin greatly help in mitigating this problem. However, there is a lack of an infant/toddler-friendly formulation for countries with limited clean water orr electricity. Here, we report the development of a shear-thinning hydrogel system for the oral delivery of amoxicillin to infant/toddler patients, without the need of clean water and refrigeration. The hydrogel formulation consists of metolose (hydroxypropyl methylcellulose) and amoxicillin. It preserves the structural integrity of antibiotics and their antibacterial activity over 12 weeks at room temperature. Pharmacokinetic profiling of mice reveals that the hydrogel formulation increases the bioavailability of drugs by ∼18% compared to that with aqueous amoxicillin formulation. More importantly, oral gavage of this formulation in a mouse model of secondary pneumococcal pneumonia significantly ameliorates inflammatory infiltration and tissue damage in lungs, with a 10-fold reduction in bacterial counts compared to those in untreated ones. Given the remarkable antibacterial efficacy as well as the use of FDA-regulated ingredients (metolose and amoxicillin), the hydrogel formulation holds great promise for rapid clinical translation.

Medical table: A major tool for antimicrobial stewardship policy

Infectious diseases are unpredictable, with heterogeneous clinical presentations, diverse pathogens, and various susceptibility rates to anti-infective agents. These features lead to a wide variety of clinical practices, which in turn strongly limits their evaluation. We have been using a medical table since 2005 to monitor the medical activity in our department. The observation of heterogeneous therapeutic practices led to drafting up our own antibiotic guidelines and to implementing a continuous evaluation of their observance and impact on morbidity and mortality associated with infectious diseases, including adverse effects of antibiotics, duration of hospital stay, use of intensive care, and deaths. The 10-year analysis of medical practices using the medical table is based on more than 10,000 hospitalizations. It shows simplified antibiotic therapies and a reduction in infection-related morbidity and mortality. The medical table is a major tool for antimicrobial stewardship, leading to constant benefits for patients.