Improving outcomes in community-acquired pneumonia

Retrospective cohort analysis of outpatient antibiotic prescribing for community-acquired pneumonia in Canadian older adults

BACKGROUND

This retrospective cohort study is the first in North America to examine population-level appropriate antibiotic use for community-acquired pneumonia (CAP) in older adults, by agent, dose and duration. With the highest rates of CAP reported in the elderly populations, appropriate antibiotic use is essential to improve clinical outcomes. Given the ongoing crisis of antimicrobial resistance, understanding inappropriate antibiotic prescribing is integral to direct community stewardship efforts.

METHODS

All outpatient primary care visits for CAP (aged ≥65 years) were identified using physician billing codes between January 1 2014 to December 31 2018 in British Columbia (BC) and Ontario (ON). Categories of prescribing were derived from existing literature, and constructed for clinical relevance using Canadian and international guidelines available during the study period. Categories were mutually exclusive and included: guideline adherent (first-line agent, adherent dose/duration), clinically appropriate (non-first line agent, presence of comorbidities), effective but unnecessary (first-line agent, excess dose/duration), undertreatment (first-line agent, subtherapeutic dose/duration), and not recommended (non-first line agent, absence of comorbidities). Proportions of prescribing were examined by category. Temporal trends in prescribing were examined using Poisson regression.

RESULTS

A total of 436,441 episodes of CAP were identified, with 46% prescribed an antibiotic in BC, and 52% in Ontario. Guideline adherent prescribing was minimal for both provinces (BC: 2%; ON: 1%) however the largest magnitude of increase was reported in this category by the final study year (BC-Rate Ratio [RR]: 3.4, 95% Confidence Interval [CI]: 2.7-4.3; ON-RR: 4.62, 95% CI: 3.4-6.5). Clinically appropriate prescribing accounted for the most antibiotics issued, across all study years (BC: 61%; ON: 74%) (BC-RR: 0.8, 95% CI: 0.8-0.8; ON-RR: 0.9, 95% CI: 0.8-0.9). Excess duration of therapy was the hallmark characteristic for effective but unnecessary prescribing (BC: 92%; ON: 99%). The most common duration prescribed was 7 days, followed by 10. Not recommended prescribing was minimal in both provinces (BC: 4%; ON: 7%) and remained stable by the final study year (BC-RR: 1.1, 95% CI: 0.9-1.2; ON-RR: 0.9, 95% CI: 0.9-1.1).

CONCLUSION

Three quarters of antibiotic prescribing for CAP was appropriate in Ontario, but only two thirds in BC. Shortening durations-in line with evidence for 3 to 5-day treatment presents a focused target for stewardship efforts.

Risk of aortic dissection, congestive heart failure, pneumonia and acute respiratory distress syndrome in patients with clinical vertebral fracture: a nationwide population-based cohort study in Taiwan

OBJECTIVE

Studies on the association between clinical vertebral fractures (CVFs) and the subsequent risk of cardiopulmonary diseases, including aortic dissection (AD), congestive heart failure (CHF), pneumonia and acute respiratory distress syndrome (ARDS) are scarce. Therefore, we used the National Health Insurance Research Database to investigate whether patients with CVF have a heightened risk of subsequent AD, CHF, pneumonia and ARDS.

DESIGN

The National Health Insurance Research Database was used to investigate whether patients with CVFs have an increased risk of subsequent AD, CHF, pneumonia and ARDS.

PARTICIPANTS

This cohort study comprised patients aged ≥18 years with a diagnosis of CVF and were hospitalised at any point during 2000-2010 (n=1 08 935). Each CVF patient was frequency-matched to a no-CVF hospitalised patients based on age, sex, index year and comorbidities (n=1 08 935). The Cox proportional hazard regressions model was used to estimate the adjusted effect of CVF on AD, CHF, pneumonia and ARDS risk.

RESULTS

The overall incidence of AD, CHF, pneumonia and ARDS was higher in the CVF group than in the no-CVF group (4.85 vs 3.99, 119.1 vs 89.6, 283.3 vs 183.5 and 9.18 vs 4.18/10 000 person-years, respectively). After adjustment for age, sex, comorbidities and Charlson comorbidity index score, patients with CVF had a 1.23-fold higher risk of AD (95% CI=1.03-1.45), 1.35-fold higher risk of CHF (95% CI=1.30-1.40), 1.57-fold higher risk of pneumonia (95% CI=1.54-1.61) and 2.21-fold higher risk of ARDS (95% CI=1.91-2.57) than did those without CVF. Patients with cervical CVF and SCI were more likely to develop pneumonia and ARDS.

CONCLUSIONS

Our study demonstrates that CVFs are associated with an increased risk of subsequent cardiopulmonary diseases. Future investigations are encouraged to delineate the mechanisms underlying this association.

Management Of Community-Acquired Pneumonia: An Observational Study In UK Primary Care

Purpose

In primary care, initial diagnosis of community-acquired pneumonia (CAP) is made on clinical judgment without radiological confirmation or knowledge of the causative organism. Use of CRB65 score has been recommended for assessing the severity of CAP and thereby determining clinical management, but it is not known how frequently these scores are used in primary care.

Patients and methods

Primary care consultations in adults with a diagnostic code for CAP between 1 January 2009 and 31 December 2016 were extracted from the Optimum Patient Care Research Database, which at the time of data extraction had over 3.4 million patients in the UK. Episodes without antibiotic prescription on day of diagnosis were excluded, as were records describing past events. Patients admitted to hospital on day of diagnosis were excluded, but were included in exploratory analysis of CRB65 recording.

Results

In total, 4734 episodes of CAP in adults managed in primary care between 1 January 2009 and 31 December 2016 were included. A range of investigations/observations were recorded, including pulse rate (10.7%), chest examinations (9.1%) and blood tests (5.4%). CRB65 scores were recorded in 19 (0.4%) episodes of CAP, 17 of which were after the publication of the NICE guidelines in December 2014. CRB65 recording was no more frequent in 3819 episodes referred to hospital (12, 0.3%; p=0.63), but where recorded, CRB65 scores were higher (Median: 1.0 [interquartile range: 0.5–1.0] vs 2.0 [interquartile range: 1.0–2.0], p=0.04). The most commonly prescribed antibiotic was amoxicillin (40.3%), and 85.9% of episodes had a prescription length of seven days.

Conclusion

CRB65 scores are seldom recorded in UK primary care. Given that these scores are embedded in UK guidelines, further work is required to assess feasibility and barriers to use of CRB65 scores in primary care.

Bactericidal activity of ceftobiprole combined with different antibiotics against selected Gram-positive isolates

This study investigated the in vitro susceptibility of ceftobiprole and its potential synergistic activity in combination with other antimicrobials against 46 selected Gram-positive pathogens displaying resistance or decrease susceptibility to several drugs. The gradient-cross method was used to assess synergism between ceftobiprole and daptomycin, levofloxacin, linezolid, rifampicin and piperacillin/tazobactam. Time-kill curves were performed for seven representative isolates. Ceftobiprole MICs ranged from 0.25-6 mg/L for staphylococci; 4-≥32 mg/L for Enterococcus faecalis, and 0.38-≥32 mg/L for E. faecium. Ceftobiprole plus daptomycin was synergistic against all isolates. Ceftobiprole plus linezolid was synergistic against 4 isolates belonging to different species. Ceftobiprole plus levofloxacin was synergistic only against enterococci. In conclusion, ceftobiprole exhibited a potent in vitro antibacterial activity and exhibited synergy with daptomycin against all Gram-positive isolates, despite their antibiotic resistance phenotypes. The use of ceftobiprole in combination may provide a promising alternative therapy for the treatment of resistant Gram-positive infections.

Changes in pulmonary artery systolic pressure correlate with radiographic severity and peripheral oxygenation in adults with community-acquired pneumonia

PURPOSE

The aim of this prospective observational study was to evaluate the relationship between changes in pulmonary artery systolic pressure (ΔPASP) and both severity of community-acquired pneumonia (CAP) and changes in peripheral blood oxygen partial pressure (PaO₂ ).

MATERIALS AND METHODS

Seventy-five consecutive adult patients hospitalized for treatment of CAP were recruited in this single-center cohort study. Doppler echocardiographic measurement of PASP was performed by 2 staff cardiologists. Follow-up assessment was performed within 2 to 4 weeks of ending antibiotic treatment at radiographic resolution of CAP. Fifteen patients were excluded during follow-up due to confirmation of chronic obstructive pulmonary disease.

RESULTS

Pneumonia was unilateral in 40 (66.7%) and bilateral in 20 (33.3%) patients. Radiographic extent of pneumonia involved 2 pulmonary segments in 31 patients (51.7%), 3 to 5 pulmonary segments in 25 (41.7%), and 6 pulmonary segments in 4 patients (6.6%). ΔPASP between hospital admission and follow-up correlated with the number of pulmonary segments involved (Rho = 0.953; P < .001) and PaO₂ (Rho = -0.667; P < .001). The maximum PASP was greater during pneumonia than after resolution (34.82 ± 3.96 vs. 22.67 ± 4.04, P < .001).

CONCLUSIONS

Changes in PASP strongly correlated with radiological severity of CAP and PaO₂ . During pneumonia, PASP appeared increased without significant change in left ventricular filling pressures. This suggests that disease-related changes in lung tissue caused by pneumonia may easily and reproducibly be assessed using conventional noninvasive bedside diagnostics such as echocardiography and arterial blood gas analysis.

Pneumolysin as a potential therapeutic target in severe pneumococcal disease

Acute pulmonary and cardiac injury remain significant causes of morbidity and mortality in those afflicted with severe pneumococcal disease, with the risk for early mortality often persisting several years beyond clinical recovery. Although remaining to be firmly established in the clinical setting, a considerable body of evidence, mostly derived from murine models of experimental infection, has implicated the pneumococcal, cholesterol-binding, pore-forming toxin, pneumolysin (Ply), in the pathogenesis of lung and myocardial dysfunction. Topics covered in this review include the burden of pneumococcal disease, risk factors, virulence determinants of the pneumococcus, complications of severe disease, antibiotic and adjuvant therapies, as well as the structure of Ply and the role of the toxin in disease pathogenesis. Given the increasing recognition of the clinical potential of Ply-neutralisation strategies, the remaining sections of the review are focused on updates of the types, benefits and limitations of currently available therapies which may attenuate, directly and/or indirectly, the injurious actions of Ply. These include recently described experimental therapies such as various phytochemicals and lipids, and a second group of more conventional agents the members of which remain the subject of ongoing clinical evaluation. This latter group, which is covered more extensively, encompasses macrolides, statins, corticosteroids, and platelet-targeted therapies, particularly aspirin.

Sensitivity and Specificity of Soluble Triggering Receptor Expressed on Myeloid Cells-1, Midregional Proatrial Natriuretic Peptide and Midregional Proadrenomedullin for Distinguishing Etiology and to Assess Severity in Community-Acquired Pneumonia

Study Design

This study aimed to evaluate the diagnostic accuracy of soluble triggering receptor expressed on myeloid cells-1 (sTREM-1), midregional proatrial natriuretic peptide (MR-proANP) and midregional proadrenomedullin (MR-proADM) to distinguish bacterial from viral community-acquired pneumonia (CAP) and to identify severe cases in children hospitalized for radiologically confirmed CAP. Index test results were compared with those derived from routine diagnostic tests, i.e., white blood cell (WBC) counts, neutrophil percentages, and serum C-reactive protein (CRP) and procalcitonin (PCT) levels.

Methods

This prospective, multicenter study was carried out in the most important children’s hospitals (n = 11) in Italy and 433 otherwise healthy children hospitalized for radiologically confirmed CAP were enrolled. Among cases for whom etiology could be determined, CAP was ascribed to bacteria in 235 (54.3%) children and to one or more viruses in 111 (25.6%) children. A total of 312 (72.2%) children had severe disease.

Results

CRP and PCT had the best performances for both bacterial and viral CAP identification. The cut-off values with the highest combined sensitivity and specificity for the identification of bacterial and viral infections using CRP were ≥7.98 mg/L and ≤7.5 mg/L, respectively. When PCT was considered, the cut-off values with the highest combined sensitivity and specificity were ≥0.188 ng/mL for bacterial CAP and ≤0.07 ng/mL for viral CAP. For the identification of severe cases, the best results were obtained with evaluations of PCT and MR-proANP. However, in both cases, the biomarker cut-off with the highest combined sensitivity and specificity (≥0.093 ng/mL for PCT and ≥33.8 pmol/L for proANP) had a relatively good sensitivity (higher than 70%) but a limited specificity (of approximately 55%).

Conclusions

This study indicates that in children with CAP, sTREM-1, MR-proANP, and MR-proADM blood levels have poor abilities to differentiate bacterial from viral diseases or to identify severe cases, highlighting that PCT maintains the main role at this regard.

Measurement of lipocalin-2 and syndecan-4 levels to differentiate bacterial from viral infection in children with community-acquired pneumonia

Background

In this study, we evaluated the lipocalin-2 (LIP2) and syndecan-4 (SYN4) levels in children who were hospitalized for radiologically confirmed CAP in order to differentiate bacterial from viral infection. The results regarding the LIP2 and SYN4 diagnostic outcomes were compared with the white blood cell (WBC) count and C reactive protein (CRP) levels.

Methods

A total of 110 children <14 years old who were hospitalized for radiologically confirmed CAP were enrolled. Serum samples were obtained upon admission and on day 5 to measure the levels of LIP2, SYN4, and CRP as well as the WBC. Polymerase chain reaction of the respiratory secretions and tests on blood samples were performed to detect respiratory viruses, Streptococcus pneumoniae, and Mycoplasma pneumoniae.

Results

CAP was considered to be due to a probable bacterial infection in 74 children (67.3 %) and due to a probable viral infection in 16 children (14.5 %). Overall, 84 children (76.4 %) were diagnosed with severe CAP. The mean values of the WBC count and the LIP2 and SYN4 levels did not differ among the probable bacterial, probable viral, and undetermined cases. However, the CRP serum concentrations were significantly higher in children with probable bacterial CAP than in those with probable viral disease (32.2 ± 55.5 mg/L vs 9.4 ± 17.0 mg/L, p < 0.05). The WBC count was the best predictor of severe CAP, but the differences among the studied variables were marginal. The WBC count was significantly lower on day 5 in children with probable bacterial CAP (p < 0.01) and in those with an undetermined etiology (p < 0.01). The CRP and LIP2 levels were significantly lower 5 days after enrollment in all of the studied groups, independent of the supposed etiology of CAP (p < 0.01 for all comparisons). No statistically significant variation was observed for SYN4.

Conclusions

Measuring the LIP2 and SYN4 levels does not appear to solve the problem of the poor reliability of routine laboratory tests in defining the etiology and severity of pediatric CAP. Currently, the CRP levels and WBC, when combined with evaluation of clinical data, can be used to limit the overuse of antibiotics as much as possible and to provide the best treatment to the patient.