Use of Pulmonary Computed Tomography for Evaluating Suspected Stroke-Associated Pneumonia.

OBJECTIVES: Accurate and timely diagnosis of pneumonia complicating stroke remains challenging and the diagnostic accuracy of chest X-ray (CXR) in the setting of stroke-associated pneumonia (SAP) is uncertain. The overall objective of this study was to evaluate the use of pulmonary computed tomography (CT) in diagnosis of suspected SAP. MATERIALS AND METHODS: Patients with acute ischemic stroke (IS) or intracerebral hemorrhage (ICH) were recruited within 24h of clinically suspected SAP and underwent non-contrast pulmonary CT within 48h of antibiotic initiation. CXR and pulmonary CT were reported by two radiologists. Pulmonary CT was used as the reference standard for final diagnosis of SAP. Sensitivity, specificity, positive and negative predictive values (PPV and NPV), and diagnostic odds ratio (OR) for CXR were calculated. RESULTS: 40 patients (36 IS, 4 ICH) with a median age of 78y (range 44y-90y) and a median National Institute of Health Stroke Scale score of 13 (range 3-31) were included. All patients had at least one CXR and 35/40 patients (88%) underwent pulmonary CT. Changes consistent with pneumonia were present in 15/40 CXRs (38%) and 12/35 pulmonary CTs (34%). 9/35 pulmonary CTs (26%) were reported normal. CXR had a sensitivity of 58.3%, specificity of 73.9%, PPV of 53.8 %, NPV of 77.2 %, diagnostic OR of 3.7 (95% CI 0.7 - 22) and an accuracy of 68.5% (95% CI 50.7% -83.1%). DISCUSSION: CXR has limited diagnostic accuracy in SAP. The majority of patients started on antibiotics had no evidence of pneumonia on pulmonary CT with potential implications for antibiotic stewardship. CONCLUSIONS: Pulmonary CT could be applied as a reference standard for evaluation of clinical and biomarker diagnostic SAP algorithms in multi-center studies.

Antibiotic Class and Outcome in Post-stroke Infections: An Individual Participant Data Pooled Analysis of VISTA-Acute.

Introduction: Antibiotics used to treat post-stroke infections have differing antimicrobial and anti-inflammatory effects. Our aim was to investigate whether antibiotic class was associated with outcome after post-stroke infection. Methods: We analyzed pooled individual participant data from the Virtual International Stroke Trials Archive (VISTA)-Acute. Patients with ischemic stroke and with an infection treated with systemic antibiotic therapy during the first 2 weeks after stroke onset were eligible. Antibiotics were grouped into eight classes, according to antimicrobial mechanism and prevalence. The primary analysis investigated whether antibiotic class for any infection, or for pneumonia, was independently associated with a shift in 90 day modified Rankin Scale (mRS) using ordinal logistic regression. Results: 2,708 patients were eligible (median age [IQR] = 74 [65 to 80] y; 51% female; median [IQR] NIHSS score = 15 [11 to 19]). Pneumonia occurred in 35%. Treatment with macrolides (5% of any infections; 9% of pneumonias) was independently associated with more favorable mRS distribution for any infection [OR (95% CI) = 0.59 (0.42 to 0.83), p = 0.004] and for pneumonia [OR (95% CI) = 0.46 (0.29 to 0.73), p = 0.001]. Unfavorable mRS distribution was independently associated with treatment of any infection either with carbapenems, cephalosporins or monobactams [OR (95% CI) = 1.62 (1.33 to 1.97), p < 0.001], penicillin plus ß-lactamase inhibitors [OR (95% CI) = 1.26 (1.03 to 1.54), p = 0.025] or with aminoglycosides [OR (95% CI) = 1.73 (1.22 to 2.46), p = 0.002]. Conclusion: This retrospective study has several limitations including effect modification and confounding by indication. Macrolides may have favorable immune-modulatory effects in stroke-associated infections. Prospective evaluation of the impact of antibiotic class on treatment of post-stroke infections is warranted.

A Haemophilus sp. dominates the microbiota of sputum from UK adults with non-severe community acquired pneumonia and chronic lung disease.

The demographics and comorbidities of patients with community acquired pneumonia (CAP) vary enormously but stratified treatment is difficult because aetiological studies have failed to comprehensively identify the pathogens. Our aim was to describe the bacterial microbiota of CAP and relate these to clinical characteristics in order to inform future trials of treatment stratified by co-morbidity. CAP patients were prospectively recruited at two UK hospitals. We used 16S rRNA gene sequencing to identify the dominant bacteria in sputum and compositional data analysis to determine associations with patient characteristics. We analysed sputum samples from 77 patients and found a Streptococcus sp. and a Haemophilus sp. were the most relatively abundant pathogens. The Haemophilus sp. was more likely to be dominant in patients with pre-existing lung disease, and its relative abundance was associated with qPCR levels of Haemophilus influenzae. The most abundant Streptococcus sp. was associated with qPCR levels of Streptococcus pneumoniae but dominance could not be predicted from clinical characteristics. These data suggest chronic lung disease influences the microbiota of sputum in patients with CAP. This finding could inform a trial of stratifying empirical CAP antibiotics to target Haemophilus spp. in addition to Streptococcus spp. in those with chronic lung disease.

Antibiotic treatment for pneumonia complicating stroke: Recommendations from the pneumonia in stroke consensus (PISCES) group.

PURPOSE: The microbiological aetiology of pneumonia complicating stroke is poorly characterised. In this second Pneumonia in Stroke ConsEnsuS statement, we propose a standardised approach to empirical antibiotic therapy in pneumonia complicating stroke, based on likely microbiological aetiology, to improve antibiotic stewardship. METHODS: Systematic literature searches of multiple databases were undertaken. An evidence review and a round of consensus consultation were completed prior to a final multi-disciplinary consensus meeting in September 2017, held in Barcelona, Spain. Consensus was approached using a modified Delphi technique and defined a priori as 75% agreement between the consensus group members.Findings: No randomised trials to guide antibiotic treatment of pneumonia complicating stroke were identified. Consensus was reached for the following: (1) Stroke-associated pneumonia may be caused by organisms associated with either community-acquired or hospital-acquired pneumonia; (2) Treatment for early stroke-associated pneumonia (<72 h of stroke onset) should cover community-acquired pneumonia organisms; (3) Treatment for late stroke-associated pneumonia (≥72 h and within seven days of stroke onset) should cover community-acquired pneumonia organisms plus coliforms +/- Pseudomonas spp. if risk factors; (4) No additional antimicrobial cover is required for patients with dysphagia or aspiration; (5) Pneumonia occurring after seven days from stroke onset should be treated as for hospital-acquired pneumonia; (6) Treatment should continue for at least seven days for each of these scenarios. DISCUSSION: Consensus recommendations for antibiotic treatment of the spectrum of pneumonia complicating stroke are proposed. However, there was limited evidence available to formulate consensus on choice of specific antibiotic class for pneumonia complicating stroke. CONCLUSION: Further studies are required to inform evidence-based treatment of stroke-associated pneumonia including randomised trials of antibiotics and validation of candidate biomarkers.

ERS syllabus for postgraduate training in respiratory infections: a guide for comprehensive training.

ERS has developed a syllabus for postgraduate training in respiratory infections to guide programme designers http://ow.ly/xJ0R30m8CYB.

Microbiological Etiologies of Pneumonia Complicating Stroke: A Systematic Review.

BACKGROUND AND PURPOSE: Identifying the causal pathogens of pneumonia complicating stroke is challenging, and antibiotics used are often broad spectrum, without recourse to the microbiological cause. We aimed to review existing literature to identify organisms responsible for pneumonia complicating stroke, before developing a consensus-based approach to antibiotic treatment. METHODS: A systematic literature review of multiple electronic databases using predefined search criteria was undertaken, in accordance with Cochrane and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidance. Published studies of hospitalized adults with ischemic stroke, intracerebral hemorrhage, or both, which identified microbiological etiologies for pneumonia complicating stroke up to January 1, 2017, were considered. Analysis included summary statistics and random-effects meta-analysis where appropriate. RESULTS: Fifteen studies (40% ischemic stroke, 60% ischemic stroke and intracerebral hemorrhage) involving 7968 patients were included. Reported occurrence of pneumonia varied considerably between studies (2%-63%) with a pooled frequency of 23% (95% confidence interval, 14%-34%; I2=99%). Where reported (60%), the majority of pneumonia occurred within 1 week of stroke (78%). Reported frequency of positive culture data (15%-88%) varied widely. When isolated, aerobic Gram-negative bacilli (38%) and Gram-positive cocci (16%) were most frequently cultured; commonly isolated organisms included Enterobacteriaceae (21.8%: Klebsiella pneumoniae, 12.8% and Escherichia coli, 9%), Staphylococcus aureus (10.1%), Pseudomonas aeruginosa (6%), Acinetobacter baumanii (4.6%), and Streptococcus pneumoniae (3.5%). Sputum was most commonly used to identify pathogens, in isolation (40%) or in conjunction with tracheal aspirate (15%) or blood culture (20%). CONCLUSIONS: Although the analysis was limited by small and heterogeneous study populations, limiting determination of microbiological causality, this review suggests aerobic Gram-negative bacilli and Gram-positive cocci are frequently associated with pneumonia complicating stroke. This supports the need for appropriately designed studies to determine microbial cause and a consensus-based approach in antibiotic usage and further targeted antibiotic treatment trials for enhanced antibiotic stewardship.

The association between pre-hospital antibiotic therapy and subsequent in-hospital mortality in adults presenting with community-acquired pneumonia: an observational study.

BACKGROUND: The majority of patients with community acquired-pneumonia (CAP) are treated in primary care and the mortality in this group is very low. However, a small but significant proportion of patients who begin treatment in the community subsequently require admission due to symptomatic deterioration. This study compared patients who received community antibiotics prior to admission to those who had not, and looked for associations with clinical outcomes. METHODS: This study analysed the Advancing Quality (AQ) Pneumonia database of patients admitted with CAP to 9 acute hospitals in the northwest of England over a 12-month period. RESULTS: There were 6348 subjects (mean age 72 [SD 16] years; gender ratio 1:1) admitted with CAP, of whom 17% had been pre-treated with antibiotics. The in-hospital mortality was 18.6% for the pre-treatment group compared to 13.2% in the "antibiotic naïve" group (p < 0.001). On multivariate analysis, age, male gender and antibiotic pre-treatment were predictors of in-hospital mortality along with a history of cerebrovascular accident, congestive cardiac failure, dementia, renal disease and cancer. After adjustment for CURB-65 score, age, co-morbidities and pre-treatment with antibiotics remained as independent risk factors for in-hospital mortality (OR 1.43, 95% CI 1.19-1.71). CONCLUSION: CAP patients admitted to hospital were more likely to die during admission if they had received antibiotics for the same illness pre-admission. Future studies should endeavor to determine the mechanisms underlying this association, such as microbiological factors and the role of comorbidities. Patients hospitalized with CAP despite prior antibiotic treatment in the community require close monitoring.

Quantifying the need for enhanced case management for TB patients as part of TB cohort audit in the North West of England: a descriptive study.

BACKGROUND: Patients with TB have diverse and often challenging clinical and social needs that may hamper successful treatment outcomes. Understanding the need for additional support during treatment (enhanced case management, or ECM) is important for workforce capacity planning. North West England TB Cohort Audit (TBCA) has introduced a 4-level ECM classification system (ECM 0-3) to quantify the need for ECM in the region. This study describes the data from the first 2 years of ECM classification. METHODS: Data collected between April 2013 and July 2015 were used to analyse the proportions of patients allocated to each ECM level and the prevalence of social and clinical factors indicating need for ECM. Single variable and multivariable logistic regression models were constructed to examine the association between ECM level and treatment outcome. RESULTS: Of 1714 notified cases 99.8% were assigned an ECM level: 31% ECM1, 19% ECM2 and 14% ECM3. The most common factors indicating need for ECM were language barriers (20.3%) and clinical complexity (16.9%). 1342/1493 (89.9%) of drug-sensitive, non-CNS cases completed treatment within 12 months. Patients in ECM2 and 3 were less likely to complete treatment at 12 months than patients in ECM0 (adjusted OR 0.47 [95% CI 0.27-0.84] and 0.23 [0.13-0.41] respectively). CONCLUSIONS: Use of TBCA to quantify different levels of need for ECM is feasible and has demonstrated that social and clinical complexity is common in the region. Results will inform regional workforce planning and assist development of innovative methods to improve treatment outcomes in these vulnerable groups.

A longitudinal modelling study estimates acute symptoms of community acquired pneumonia recover to baseline by 10†days.

Our aims were to address three fundamental questions relating to the symptoms of community-acquired pneumonia (CAP): Do patients completely recover from pneumonia symptoms? How long does this recovery take? Which factors influence symptomatic recovery?We prospectively recruited patients at two hospitals in Liverpool, UK, into a longitudinal, observational cohort study and modelled symptom recovery from CAP. We excluded patients with cancer, immunosuppression or advanced dementia, and those who were intubated or palliated from admission. We derived a statistical model to describe symptom patterns.We recruited 169 (52% male) adults. Multivariable analysis demonstrated that the time taken to recover to baseline was determined by the initial severity of symptoms. Severity of symptoms was associated with comorbidity and was inversely related to age. The pattern of symptom recovery was exponential and most patients' symptoms returned to baseline by 10 days.These results will inform the advice given to patients regarding the resolution of their symptoms. The recovery model described here will facilitate the use of symptom recovery as an outcome measure in future clinical trials.

The interaction between bronchoconstriction and cough in asthma.

Variable airflow obstruction is a pathophysiological hallmark of asthma; however, the interactions between acute bronchoconstriction and the cough reflex are poorly understood. We performed a randomised, single-blind, placebo-controlled, crossover study to investigate the interaction between bronchoconstriction and cough in asthma. Capsaicin was administered to evoke coughs and methacholine to induce bronchoconstriction. We demonstrated that acute bronchoconstriction increased capsaicin-evoked coughs, which improved as airway calibre spontaneously resolved. However, capsaicin-evoked coughing had no impact on methacholine-induced bronchoconstriction. This study provides evidence that bronchoconstriction increases the activation of capsaicin-responsive airway nerves, but the precise mechanisms and mediators involved require further evaluation. TRIAL REGISTRATION NUMBER: ISRCTN14900082.

Capsaicin-evoked cough responses in asthmatic patients: Evidence for airway neuronal dysfunction.

BACKGROUND: Cough in asthmatic patients is a common and troublesome symptom. It is generally assumed coughing occurs as a consequence of bronchial hyperresponsiveness and inflammation, but the possibility that airway nerves are dysfunctional has not been fully explored. OBJECTIVES: We sought to investigate capsaicin-evoked cough responses in a group of patients with well-characterized mild-to-moderate asthma compared with healthy volunteers and assess the influences of sex, atopy, lung physiology, inflammation, and asthma control on these responses. METHODS: Capsaicin inhalational challenge was performed, and cough responses were analyzed by using nonlinear mixed-effects modeling to estimate the maximum cough response evoked by any concentration of capsaicin (Emax) and the capsaicin dose inducing half-maximal response (ED50). RESULTS: Ninety-seven patients with stable asthma (median age, 23 years [interquartile range, 21-27 years]; 60% female) and 47 healthy volunteers (median age, 38 years [interquartile range, 29-47 years]; 64% female) were recruited. Asthmatic patients had higher Emax and lower ED50 values than healthy volunteers. Emax values were 27% higher in female subjects (P = .006) and 46% higher in patients with nonatopic asthma (P = .003) compared with healthy volunteers. Also, patients with atopic asthma had a 21% lower Emax value than nonatopic asthmatic patients (P = .04). The ED50 value was 65% lower in female patients (P = .0001) and 71% lower in all asthmatic patients (P = .0008). ED50 values were also influenced by asthma control and serum IgE levels, whereas Emax values were related to 24-hour cough frequency. Age, body mass index, FEV1, PC20, fraction of exhaled nitric oxide, blood eosinophil counts, and inhaled steroid treatment did not influence cough parameters. CONCLUSION: Patients with stable asthma exhibited exaggerated capsaicin-evoked cough responses consistent with neuronal dysfunction. Nonatopic asthmatic patients had the highest cough responses, suggesting this mechanism might be most important in type 2-low asthma phenotypes.

Mortality reduction in adult community-acquired pneumonia in the UK (2009-2014): results from the British Thoracic Society audit programme.

Community-acquired pneumonia (CAP) is a leading cause of death in the UK. In this analysis of 23 315 cases from the British Thoracic Society national CAP audit, an overall reduction in 30-day inpatient mortality over 6 years was observed-2014 compared with 2009 adjusted OR 0.86 (95% CI 0.68 to 1.08, p for trend 0.004). Significant increases in the proportions of patients who had (a) a chest X-ray and (b) the first antibiotic dose within 4 hours of admission were also observed (3.7% and 11.5% increases respectively). Further reductions in mortality may follow the 2016 National Institute for Health and Care Excellence Pneumonia Quality Standard.

Recovery from pneumonia requires efferocytosis which is impaired in smokers and those with low body mass index and enhanced by statins.

BACKGROUND: Efferocytosis (the phagocytosis of apoptotic self cells) is a key mechanism in the resolution of inflammatory processes such as community-acquired pneumonia (CAP). Efferocytosis therefore represents a modifiable target for therapy aimed at enhancing intrinsic recovery mechanisms. It is currently not known which patients recovering from CAP would mostly benefit from a strategy aimed at enhancing efferocytosis. METHODS: We recruited a cohort of patients with CAP admitted to a hospital in Liverpool. One month into recovery, subjects were invited for research bronchoscopy and bronchoalveolar lavage. An ex vivo efferocytosis assay was performed by challenging alveolar macrophages with autologous, apoptotic neutrophils. The percentage of alveolar macrophages that had undergone efferocytosis was determined by flow cytometry. We conducted a multivariable regression using a linear mixed effects model to determine which clinical parameters were most closely associated with efferocytosis. RESULTS: We observed high rates of comorbidity among this CAP cohort. Efferocytosis was measured in 22 subjects. We assessed multiple combinations of clinical parameters for association with efferocytosis and found the best-fitting model included an interaction between smoking status and prior statin use-smoking being associated with decreased efferocytosis and statin use with increased efferocytosis. These effects were modified by an association between efferocytosis and body mass index (BMI), such that as BMI increased so did efferocytosis. CONCLUSIONS: This is the first study to measure efferocytosis in patients recovering from CAP. The results suggest that smokers with low BMI have impaired efferocytosis and may benefit from a statin to boost recovery.

A systematic review of the burden of vaccine preventable pneumococcal disease in UK adults.

BACKGROUND: Invasive pneumococcal disease (IPD) and pneumococcal pneumonia are common and carry a significant morbidity and mortality. Current strategies to prevent pneumococcal disease are under review in the United Kingdom (UK). We conducted a systematic review to evaluate the burden of vaccine type adult pneumococcal disease specifically in the UK. METHODS: A systematic review conducted and reported according to MOOSE guidelines. Relevant studies from 1990 to 2015 were included. The primary outcome was the incidence of vaccine type pneumococcal disease, focussing on the pneumococcal polysaccharide vaccine (PPSV), the 13-valent conjugate vaccine (PCV13) and the 7-valent conjugate vaccine (PCV7). RESULTS: Data from surveillance in England and Wales from 2013/14 shows an incidence of 6.85 per 100,000 population across all adult age groups for IPD, and an incidence of 20.58 per 100,000 population in those aged >65 years. The corresponding incidences for PCV13 serotype IPD were 1.4 per 100,000 and 3.72 per 100,000. The most recent available data for community-acquired pneumonia (CAP) including non-invasive disease showed an incidence of 20.6 per 100,000 for adult pneumococcal CAP and 8.6 per 100,000 population for PCV13 serotype CAP. Both IPD and CAP data sources in the UK suggest an ongoing herd protection effect from childhood PCV13 vaccination causing a reduction in the proportion of cases caused by PCV13 serotypes in adults. Despite this, applying the incidence rates to UK population estimates suggests more than 4000 patients annually will be hospitalised with PCV13 serotype CAP and more than 900 will be affected by IPD, although with a trend for these numbers to decrease over time. There was limited recent data on serotype distribution in high risk groups such as those with chronic respiratory or cardiac disease and no data available for vaccine type (VT) CAP managed in the community where there is likely to be a considerable unmeasured burden. CONCLUSION: The most recent available data suggests that VT pneumococcal disease continues to have a high burden in UK adults despite the impact of childhood PCV13 vaccination. IPD estimates represent only a fraction of the total burden of pneumococcal disease. STUDY REGISTRATION: PROSPERO CRD42015025043.

Health professionals' experiences of tuberculosis cohort audit in the North West of England: a qualitative study.

OBJECTIVES: Tuberculosis cohort audit (TBCA) was introduced across the North West (NW) of England in 2012 as an ongoing, multidisciplinary, systematic case review process, designed to improve clinical and public health practice. TBCA has not previously been introduced across such a large and socioeconomically diverse area in England, nor has it undergone formal, qualitative evaluation. This study explored health professionals' experiences of the process after 1515 cases had been reviewed. DESIGN: Qualitative study using semistructured interviews. Respondents were purposively sampled from 3 groups involved in the NW TBCA: (1) TB nurse specialists, (2) consultant physicians and (3) public health practitioners. Data from the 26 respondents were triangulated with further interviews with key informants from the TBCA Steering Group and through observation of TBCA meetings. ANALYSIS: Interview transcripts were analysed thematically using the framework approach. RESULTS: Participants described the evolution of a valuable 'community of practice' where interprofessional exchange of experience and ideas has led to enhanced mutual respect between different roles and a shared sense of purpose. This multidisciplinary, regional approach to TB cohort audit has promoted local and regional team working, exchange of good practices and local initiatives to improve care. There is strong ownership of the process from public health professionals, nurses and clinicians; all groups want it to continue. TBCA is regarded as a tool for quality improvement that improves patient safety. CONCLUSIONS: TBCA provides peer support and learning for management of a relatively rare, but important infectious disease through discussion in a no-blame atmosphere. It is seen as an effective quality improvement strategy which enhances TB care, control and patient safety. Continuing success will require increased engagement of consultant physicians and public health practitioners, a secure and ongoing funding stream and establishment of clear reporting mechanisms within the public health system.

Time to first antibiotic and mortality in adults hospitalised with community-acquired pneumonia: a matched-propensity analysis.

A matched-propensity analysis of national data from the British Thoracic Society community-acquired pneumonia audit was conducted (n=13 725). Overall, time to first antibiotic (TFA) was ≤4 h in 63%. Adjusted 30-day inpatient (IP) mortality was lower for adults with TFA ≤4 h compared with TFA >4 h (adjusted OR 0.84, 95% CI 0.74 to 0.94; p=0.003). Increasing TFA was associated with greater OR of 30-day IP mortality (p value for trend=0.001), but no TFA threshold was evident. Although we found an association between TFA and mortality, we cannot say whether this is causal or whether TFA might just be a quality measure for overall or other processes of care.

Clinical risk scores for predicting stroke-associated pneumonia: A systematic review.

PURPOSE: Several risk stratification scores for predicting stroke-associated pneumonia have been derived. We aimed to evaluate the performance and clinical usefulness of such scores for predicting stroke-associated pneumonia. METHOD: A systematic literature review was undertaken in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement, with application of the Quality Assessment of Diagnostic Accuracy-2 tool. Published studies of hospitalised adults with ischaemic stroke, intracerebral haemorrhage, or both, which derived and validated an integer-based clinical risk score, or externally validated an existing score to predict occurrence of stroke-associated pneumonia, were considered and independently screened for inclusion by two reviewers. FINDINGS: We identified nine scores, from eight derivation cohorts. Age was a component of all scores, and the NIHSS score in all except one. Six scores were internally validated and five scores were externally validated. The A2DS2 score (Age, Atrial fibrillation, Dysphagia, Severity [NIHSS], Sex) was the most externally validated in 8 independent cohorts. Performance measures were reported for eight scores. Discrimination tended to be more variable in the external validation cohorts (C statistic 0.67-0.83) than the derivation cohorts (C statistic 0.74-0.85). DISCUSSION: Overall, discrimination and calibration were similar between the different scores. No study evaluated influence on clinical decision making or prognosis. CONCLUSION: The clinical prediction scores varied in their simplicity of use and were comparable in performance. Utility of such scores for preventive intervention trials and in clinical practice remains uncertain and requires further study.

Diagnosis of Stroke-Associated Pneumonia: Recommendations From the Pneumonia in Stroke Consensus Group.

BACKGROUND AND PURPOSE: Lower respiratory tract infections frequently complicate stroke and adversely affect outcome. There is currently no agreed terminology or gold-standard diagnostic criteria for the spectrum of lower respiratory tract infections complicating stroke, which has implications for clinical practice and research. The aim of this consensus was to propose standardized terminology and operational diagnostic criteria for lower respiratory tract infections complicating acute stroke. METHODS: Systematic literature searches of multiple electronic databases were undertaken. An evidence review and 2 rounds of consensus consultation were completed before a final consensus meeting in September 2014, held in Manchester, United Kingdom. Consensus was defined a priori as ≥75% agreement between the consensus group members. RESULTS: Consensus was reached for the following: (1) stroke-associated pneumonia (SAP) is the recommended terminology for the spectrum of lower respiratory tract infections within the first 7 days after stroke onset; (2) modified Centers for Disease Control and Prevention (CDC) criteria are proposed for SAP as follows-probable SAP: CDC criteria met, but typical chest x-ray changes absent even after repeat or serial chest x-ray; definite SAP: CDC criteria met, including typical chest x-ray changes; (3) there is limited evidence for a diagnostic role of white blood cell count or C-reactive protein in SAP; and (4) there is insufficient evidence for the use of other biomarkers (eg, procalcitonin). CONCLUSIONS: Consensus operational criteria for the terminology and diagnosis of SAP are proposed based on the CDC criteria. These require prospective evaluation in patients with stroke to determine their reliability, validity, impact on clinician behaviors (including antibiotic prescribing), and clinical outcomes.

How is pneumonia diagnosed in clinical stroke research? A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Diagnosis of pneumonia complicating stroke is challenging, and there are currently no consensus diagnostic criteria. As a first step in developing such consensus-based diagnostic criteria, we undertook a systematic review to identify the existing diagnostic approaches to pneumonia in recent clinical stroke research to establish the variation in diagnosis and terminology. METHODS: Studies of ischemic stroke, intracerebral hemorrhage, or both, which reported occurrence of pneumonia from January 2009 to March 2014, were considered and independently screened for inclusion by 2 reviewers after multiple searches using electronic databases. The primary analysis was to identify existing diagnostic approaches for pneumonia. Secondary analyses explored potential reasons for any heterogeneity where standard criteria for pneumonia had been applied. RESULTS: Sixty-four studies (56% ischemic stroke, 6% intracerebral hemorrhage, 38% both) of 639 953 patients were included. Six studies (9%) reported no information on the diagnostic approach, whereas 12 (19%) used unspecified clinician-reported diagnosis or initiation of antibiotics. The majority used objective diagnostic criteria: 20 studies (31%) used respiratory or other published standard criteria; 26 studies (41%) used previously unpublished ad hoc criteria. The overall occurrence of pneumonia was 14.3% (95% confidence interval 13.2%-15.4%; I(2)=98.9%). Occurrence was highest in studies applying standard criteria (19.1%; 95% confidence interval 15.1%-23.4%; I(2)=98.5%). The substantial heterogeneity observed was not explained by stratifying for other potential confounders. CONCLUSIONS: We found considerable variation in terminology and the diagnostic approach to pneumonia. Our review supports the need for consensus development of operational diagnostic criteria for pneumonia complicating stroke.