Diagnosis of ambulatory community-acquired pneumonia. Comparison of clinical assessment versus chest X-ray

Community-acquired pneumonia - use of chest x-rays for diagnosis in family practice

Background

According to guidelines, the diagnosis of pneumonia should be confirmed by chest x-ray, ensuring appropriate management and wise use of antibiotics. Our study aimed to describe use of x-rays by family doctors and patients following diagnosis of pneumonia in primary care practices in the north of Israel.

Methods

This was a retrospective database study including adults diagnosed with pneumonia, assessing rates of referral and actual use of chest x-rays. We examined rates of referral for chest x-rays and rates of adherence to the referral, according to age, gender, smoking status, comorbidities and distance of residence from the radiology facility.

Results

During one year there were 4,230 diagnosed cases of pneumonia in the practice, of which 2,503 were referred for chest x-rays, and 1,920 adhered to the referral (45% of those diagnosed with pneumonia). The rate of referral was higher when the radiology facility was located in the same city as the family doctor compared to outside the city (69.7% and 53.2%, p < 0.001). Patients aged 40–64 were referred more than patients aged 18–39 or 65+ (61.5% vs. 56.5% and 58.3%, p = 0.03). Actual use of chest x-rays (considering both referral and adherence) was more likely when the radiology facility was in the same health centre or city than when it was outside the city [OR = 2.4; 95% CI: 2.1–2.8]; patients aged 65 + or 40–64 were more likely to adhere to the referral for x-ray than those aged 18–39 [OR = 1.3; 95% CI: 1.1–1.6, OR = 1.2; 95% CI: 1.0–1.4, respectively].

Conclusion

Accessibility of radiology facilities seems to be an important factor associated with both doctors’ decisions and patients’ adherence to the referral for chest x-rays.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-022-01872-y.

Applying machine learning algorithms to electronic health records predicted pneumonia after respiratory tract infection

OBJECTIVES

To predict community acquired pneumonia (CAP) after respiratory tract infection (RTI) consultations in primary care by applying machine learning to electronic health records (EHRs).

STUDY DESIGN AND SETTING

A population-based cohort study was conducted using primary care electronic health records between 2002 to 2017. 16,289 patients who consulted with RTIs then subsequently diagnosed with pneumonia within 30 days were compared with a random sample of eligible RTI patients. Variable selection compared logistic regression, random forest and penalized regression models. Prediction models were developed using classification and regression trees (CART) and logistic regression. Model performance was assessed through internal and temporal validations.

RESULTS

Older age, comorbidity and initial presentation with lower respiratory tract infection (LRTIs) were identified as the main predictors of pneumonia diagnosis. Developed models achieved good discrimination accuracy with AUROC for the logistic regression model being 0.81 (0.80, 0.84) and 0.70 (0.69, 0.71) for CART during internal validation, and 0.80 (0.79, 0.81) vs 0.68 (0.67, 0.69) for temporal validation.

CONCLUSION

From a large number of candidate variables, a small number of predictors of pneumonia were consistently identified through machine learning variable selection procedures. Logistic regression generally provided better model performance than CART models.

[Management of Adult Community-Acquired Pneumonia and Prevention - Update 2021 - Guideline of the German Respiratory Society (DGP), the Paul-Ehrlich-Society for Chemotherapy (PEG), the German Society for Infectious Diseases (DGI), the German Society of Medical Intensive Care and Emergency Medicine (DGIIN), the German Viological Society (DGV), the Competence Network CAPNETZ, the German College of General Practitioneers and Family Physicians (DEGAM), the German Society for Geriatric Medicine (DGG), the German Palliative Society (DGP), the Austrian Society of Pneumology Society (ÖGP), the Austrian Society for Infectious and Tropical Diseases (ÖGIT), the Swiss Respiratory Society (SGP) and the Swiss Society for Infectious Diseases Society (SSI)]

The present guideline provides a new and updated concept of the management of adult patients with community-acquired pneumonia. It replaces the previous guideline dating from 2016.The guideline was worked out and agreed on following the standards of methodology of a S3-guideline. This includes a systematic literature search and grading, a structured discussion of recommendations supported by the literature as well as the declaration and assessment of potential conflicts of interests.The guideline has a focus on specific clinical circumstances, an update on severity assessment, and includes recommendations for an individualized selection of antimicrobial treatment.The recommendations aim at the same time at a structured assessment of risk for adverse outcome as well as an early determination of treatment goals in order to reduce mortality in patients with curative treatment goal and to provide palliation for patients with treatment restrictions.

Systematic review of the impact of appropriate versus inappropriate initial antibiotic therapy on outcomes of patients with severe bacterial infections

We investigated the impact of appropriate versus inappropriate initial antimicrobial therapy on the clinical outcomes of patients with severe bacterial infections as part of a systematic review and meta-analyses assessing the impact of delay in appropriate antimicrobial therapy. Literature searches of MEDLINE and Embase, conducted on 24 July 2018, identified studies published after 2007 reporting the impact of delay in appropriate antibiotic therapy for hospitalised adult patients with bacterial infections. Results were statistically pooled for outcomes including mortality, hospital length of stay (LOS) and treatment failure. Subgroup analyses were explored by site of infection where data permitted. Inclusion criteria were met by 145 studies, of which 114 reported data on the impact of appropriate versus inappropriate initial therapy. In the pooled analysis, rates of mortality were significantly in favour of appropriate therapy [odds ratio (OR) = 0.44, 95% CI 0.38-0.50]. Across eight studies, LOS was shorter with appropriate therapy compared with inappropriate therapy [mean difference (MD) -2.54 days (95% CI -5.30 to 0.23)], but not significantly so. The incidence of treatment failure was significantly lower in patients who received appropriate therapy compared with patients who received inappropriate therapy (six studies: OR = 0.33, 95% CI 0.16-0.66) as was mean hospital costs (four studies: MD -7.38 thousand US$ or Euros, 95% CI -14.14 to -0.62). Initiation of appropriate versus inappropriate antibiotics can reduce mortality, reduce treatment failure and decrease LOS, highlighting the importance of broad‑spectrum empirical therapy and rapid diagnostics for early identification of the causative pathogen. [Study registration: PROSPERO: CRD42018104669].

Use of chest X-ray in the assessment of community acquired pneumonia in primary care - an intervention study

OBJECTIVES

The aim of this study was to explore if consequent use of chest X-ray (CXR), when the physician is not sure of the diagnosis of pneumonia after clinical examination and CRP-testing, favors a more restrictive prescribing of antibiotics.

DESIGN

This was an intervention study conducted between September 2015 and December 2017.

SETTING

Two intervention primary health care centers (PHCCs) and three control PHCCs in the southeast of Sweden.

INTERVENTION

All patients were referred for CXR when the physician´s suspicion of pneumonia was 'unsure', or 'quite sure' after CRP-testing. Control units managed patients according to their usual routine after clinical examination and CRP-testing.

SUBJECTS

A total of 104 patients were included in the intervention group and 81 patients in the control group. The inclusion criteria of the study were clinically suspected pneumonia in patients ≥18 years, with respiratory symptoms for more than 24 h. Main outcome measure: Antibiotic prescribing rate.

RESULTS

In the intervention group, 85% were referred for CXR and 69% were prescribed antibiotics, as compared to 26% and 77% in the control group. The difference in antibiotic prescribing rate was not statistically significant, unadjusted OR 0.68 [0.35-1.3] and adjusted OR 1.1 [CI 0.43-3.0]. A total of 24% of patients with negative CXR were prescribed antibiotics.

CONCLUSION

This study could not prove that use of CXR when the physician was not sure of the diagnosis of pneumonia results in lowered antibiotic prescribing rate in primary care. In cases of negative findings on CXR the physicians do not seem to rely on the outcome when it comes to antibiotic prescribing. Key Points Routine use of chest X-ray when the clinical diagnosis of pneumonia is uncertain has not been proven to result in lowered antibiotic prescribing rate. Physicians do not fully rely on chest X-ray outcome and to some extent prescribe antibiotics even if negative, when community-acquired pneumonia is suspected. Chest X-ray is already used in one out of four cases in routine primary care of pneumonia patients in Sweden.

Accuracy of Signs and Symptoms for the Diagnosis of Community-acquired Pneumonia: A Meta-analysis

BACKGROUND

Community-acquired pneumonia (CAP) is an important source of morbidity and mortality. However, overtreatment of acute cough illness with antibiotics is an important problem, so improved diagnosis of CAP could help reduce inappropriate antibiotic use.

METHODS

This was a meta-analysis of prospective cohort studies of patients with clinically suspected pneumonia or acute cough that used imaging as the reference standard. All studies were reviewed in parallel by two researchers and quality was assessed using the QUADAS-2 criteria. Summary measures of accuracy included sensitivity, specificity, likelihood ratios, the diagnostic odds ratio, and the area under the receiver operating characteristic curve (AUROCC) and were calculated using bivariate meta-analysis.

RESULTS

We identified 17 studies, of which 12 were judged to be at low risk of bias and the remainder at moderate risk of bias. The prevalence of CAP was 10% in nine primary care studies and was 20% in seven emergency department studies. The probability of CAP is increased most by an abnormal overall clinical impression suggesting CAP (positive likelihood ratio [LR+] = 6.32, 95% CI = 3.58 to 10.5), egophony (LR+ = 6.17, 95% CI = 1.34 to 18.0), dullness to percussion (LR+ = 2.62, 95% CI = 1.14 to 5.30), and measured temperature (LR+ = 2.52, 95% CI = 2.02 to 3.20), while it is decreased most by the absence of abnormal vital signs (LR- = 0.25, 95% CI = 0.11 to 0.48). The overall clinical impression also had the highest AUROCC at 0.741.

CONCLUSIONS

While most individual signs and symptoms were unhelpful, selected signs and symptoms are of value for diagnosing CAP. Teaching and performing these high value elements of the physical examination should be prioritized, with the goal of better targeting chest radiographs and ultimately antibiotics.

A Systematic Review of the Effect of Delayed Appropriate Antibiotic Treatment on the Outcomes of Patients With Severe Bacterial Infections

BACKGROUND

Patients with severe bacterial infections often experience delay in receiving appropriate treatment. Consolidated evidence of the impact of delayed appropriate treatment is needed to guide treatment and improve outcomes.

RESEARCH QUESTION

What is the impact of delayed appropriate antibacterial therapy on clinical outcomes in patients with severe bacterial infections?

STUDY DESIGN AND METHODS

Literature searches of MEDLINE and Embase, conducted on July 24, 2018, identified studies published after 2007 reporting the impact of delayed appropriate therapy on clinical outcomes for hospitalized adult patients with bacterial infections. Where appropriate, results were pooled and analyzed with delayed therapy modeled three ways: delay vs no delay in receiving appropriate therapy; duration of delay; and inappropriate vs appropriate initial therapy. This article reports meta-analyses on the effect of delay and duration of delay.

RESULTS

The eligibility criteria were met by 145 studies, of which 37 contributed data to analyses of effect of delay. Mortality was significantly lower in patients receiving appropriate therapy without delay compared with those experiencing delay (OR, 0.57; 95% CI, 0.45-0.72). Mortality was also lower in the no-delay group compared with the delay group in subgroups of studies reporting mortality at 20 to 30 days, during ICU stay, or in patients with bacteremia (OR, 0.57 [95% CI, 0.43-0.76]; OR, 0.47 [95% CI, 0.27-0.80]; and OR, 0.54 [95% CI, 0.40-0.75], respectively). No difference was found in time to appropriate therapy between those who died and those who survived (P = .09), but heterogeneity between studies was high.

INTERPRETATION

Avoiding delayed appropriate therapy is essential to reduce mortality in patients with severe bacterial infections.

CLINICAL TRIAL REGISTRATION

PROSPERO; No.: CRD42018104669; URL: www.crd.york.ac.uk/prospero/.

Change in the use of diagnostic tests in the management of lower respiratory tract infections: a register-based study in primary care

Background

Differentiating between pneumonia and acute bronchitis is often difficult in primary care. There is no consensus regarding clinical decision rules for pneumonia, and guidelines differ between countries. Use of diagnostic tests and change of management over time is not known.

Aim

To calculate the proportion of diagnostic tests in the management of lower respiratory tract infections (LRTIs) in a low antibiotic prescribing country, and to evaluate if the use and prescription pattern has changed over time.

Design & setting

A register-based study on data from electronic health records from January 2006 to December 2014 in the Kronoberg county of south east Sweden.

Method

Data regarding use of C-reactive protein (CRP), chest x-rays (CXRs), microbiological tests, and antibiotic prescriptions were assessed for patients aged 18–79 years, with the diagnosis pneumonia, acute bronchitis, or cough.

Results

A total of 54 229 sickness episodes were analysed. Use of CRP increased during the study period from 61.3% to 77.5% for patients with pneumonia (P<0.001), and from 53.4% to 65.7% for patients with acute bronchitis (P<0.001). Use of CXR increased for patients with acute bronchitis from 3.1% to 5.1% (P<0.001). Use of microbiological tests increased for patients with pneumonia, from 1.8% to 5.1% (P<0.001). The antibiotic prescription rate decreased from 18.6 to 8.2 per 1000 inhabitants per year for patients with acute bronchitis, but did not change for patients with pneumonia.

Conclusion

Use of CRP and microbiological tests in the diagnostics of LRTIs increased despite the fact that the incidence of pneumonia and acute bronchitis was stable.

Association Between Sub-types of Sibling Bullying and Mental Health Distress Among Chinese Children and Adolescents

Sibling bullying is a common phenomenon in childhood and adolescence worldwide and has a significant association with mental health distress. However, there have been few studies that have examined the associations between any specific sub-type of sibling bullying and depression as well as anxiety. Besides, the association between sibling bullying and psychological well-being was never explored among the Chinese population. The purpose of this cross-sectional study was to examine the associations between the number of sub-types of sibling bullying involvement and depression as well as anxiety among Chinese children and adolescents. Multi-stage stratified cluster sampling was used to recruit 5,926 participants aged 10 to 18 who had at least one sibling living in the household. Different sub-types of sibling bullying involvement were determined by using Olweus Bully/Victim Questionnaire (OBVQ). The nine-item Patient Health Questionnaire (PHQ-9) and the seven-item Generalized Anxiety Disorder Scale (GAD-7) were used to screen clinical ranges of major depression and generalized anxiety disorder, respectively. Of the participants, 1,235 (20.8%) were bullied by siblings, and 1,230 (20.8%) perpetrated bullying behavior against siblings over the past 6 months. After controlling potential confounders, adjusted model of logistic regression analyses indicated that all three sub-types of sibling victimization and perpetration were significantly associated with both depression and anxiety. There were linear associations between the number of sub-types of sibling bullying victimization and depression (adjusted OR = 1.49, 95% CI 1.32 to 1.68) as well as anxiety (adjusted OR = 1.68, 95% CI 1.48 to 1.90). Besides, linear trends were found between the number of sub-types of sibling bullying perpetration and depression (adjusted OR = 1.44, 95% CI 1.26 to 1.64) as well as anxiety (adjusted OR = 1.63, 95% CI 1.42 to 1.87). The findings underline dose-response relationships between the number of sub-types of sibling bullying involvement and mental health distress. Intervention programs should be conducted to focus on developing mental health status of those children and adolescents who are involved in multiple sub-types of sibling victimization or perpetration.

Validity of the diagnosis of pneumonia in hospitalised patients with COPD

Rationale

Exacerbations of chronic obstructive pulmonary disease (COPD) and pneumonia are two of the most common reasons for acute hospital admissions. Acute exacerbations and pneumonia present with similar symptoms in COPD patients, representing a diagnostic challenge with a significant impact on patient outcomes. The objectives of this study were to compare the prevalence of radiographic consolidation with the discharge diagnoses of hospitalised COPD patients.

Methods

COPD patients admitted to three UK hospitals over a 3-year period were identified. Participants were included if they were admitted with an acute respiratory illness, COPD was confirmed by spirometry and a chest radiograph was performed within 24 h of admission. Pneumonia was defined as consolidation on chest radiograph reviewed by two independent observers

Results

There were 941 admissions in 621 patients included in the final analysis. In 235 admissions, consolidation was present on chest radiography and there were 706 admissions without consolidation. Of the 235 admissions with consolidation, only 42.9% had a discharge diagnosis of pneumonia; 90.7% of patients without consolidation had a discharge diagnosis of COPD exacerbation. The presence of consolidation was associated with increased rate of high-dependency care admission, increased mortality and prolonged length of stay. Inhaled corticosteroid use was associated with recurrent pneumonia.

Conclusions

Pneumonia is underdiagnosed in patients with COPD. Radiographic consolidation is associated with worse outcomes and prolonged length of stay. Incorrect diagnosis could result in inappropriate use of inhaled corticosteroids. Future guidelines should specifically address the diagnosis and management of pneumonia in COPD.

Pneumonia is common in hospitalised COPD patients but is frequently not recognised and underdiagnosed. This has implications for the correct risk stratification and treatment of COPD patients.http://bit.ly/2HTfIKo

Clinical gestalt to diagnose pneumonia, sinusitis, and pharyngitis: a meta-analysis

BACKGROUND

The overall clinical impression ('clinical gestalt') is widely used for diagnosis but its accuracy has not been systematically studied.

AIM

To determine the accuracy of clinical gestalt for the diagnosis of community-acquired pneumonia (CAP), acute rhinosinusitis (ARS), acute bacterial rhinosinusitis (ABRS), and streptococcal pharyngitis, and to contrast it with the accuracy of clinical decision rules (CDRs).

DESIGN AND SETTING

Systematic review and meta-analysis of outpatient diagnostic accuracy studies in ambulatory care.

METHOD

PubMed and Google were searched for studies in outpatients that reported sufficient data to calculate accuracy of the overall clinical impression and that used the same reference standard. Study quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2), and measures of accuracy calculated using bivariate meta-analysis.

RESULTS

The authors identified 16 studies that met the inclusion criteria. The summary estimates for the positive (LR+) and negative likelihood ratios (LR-) were LR+ 7.7, 95% confidence interval (CI) = 4.8 to 11.5, and LR- 0.54, 95% CI = 0.42 to 0.65 for CAP in adults, LR+ 2.7, 95% CI = 1.1 to 4.3 and LR- 0.63, 95% CI = 0.20 to 0.98 for CAP in children, LR+ 3.0, 95% CI = 2.1 to 4.4 and LR- 0.37, 95% CI = 0.29 to 0.46 for ARS in adults, LR+ 3.9, 95% CI = 2.4 to 5.9 and LR- 0.33, 95% CI = 0.20 to 0.50 for ABRS in adults, and LR+ 2.1, 95% CI = 1.6 to 2.8 and LR- 0.47, 95% CI = 0.36 to 0.60 for streptococcal pharyngitis in adults and children. The diagnostic odds ratios were highest for CAP in adults (14.2, 95% CI = 9.0 to 21.0), ARS in adults (8.3, 95% CI = 4.9 to 13.1), and ABRS in adults (13.0, 95% CI = 5.0 to 27.0), as were the C-statistics (0.80, 0.77, and 0.84 respectively).

CONCLUSION

The accuracy of the overall clinical impression compares favourably with the accuracy of CDRs. Studies of diagnostic accuracy should routinely include the overall clinical impression in addition to individual signs and symptoms, and research is needed to optimise its teaching.

[Twenty-five myths in infectious diseases in primary care associated with overdiagnosis and overtreatment]

Overdiagnosis and overprescribing is common in current clinical practice of infectious diseases in primary care. On the basis of studies published in the medical literature we identify my means of a non-systematic review a total of 25 myths associated with the diagnosis and treatment and present the literature pertaining to each myth. These myths result in extraneous testing (overdiagnosis) and excessive antimicrobial treatment (overtreatment). Most of these myths are ingrained among general practitioners in our country. Not only should these myths be debunked from our clinical practice, but they should also be reversed, and we encourage our readers to critically appraise their practice when it comes down to the misconceptions treated in this manuscript. We attempt to give guidance to clinicians facing these frequent clinical scenarios.

Pneumonia and inflammation in acute decompensated heart failure: a registry-based analysis of 1939 patients

Background:

The prognostic impact of pneumonia and signs of systemic inflammation in patients with acute decompensated heart failure (ADHF) has not been fully elucidated yet. The aim of the present study was thus to investigate the association of pneumonia and the inflammation surrogate C-reactive protein with all-cause mortality in patients admitted for ADHF.

Methods:

We analysed data of 1939 patients admitted for ADHF. Patients were dichotomised according to the presence or absence of pneumonia. The primary endpoint of all-cause mortality was determined by death registry linkage.

Results:

In total, 412 (21.2%) patients had concomitant pneumonia. Median C-reactive protein levels were higher in patients with compared to patients without pneumonia (24.9 versus 9.8 mg/l, respectively; P<0.001). All-cause mortality was significantly higher in patients with pneumonia ( P<0.001). In adjusted Cox regression models, pneumonia as well as C-reactive protein were independently associated with in-hospital mortality. Only C-reactive protein remained as independent predictor for long-term mortality.

Conclusion:

Pneumonia is relatively common in ADHF and a predictor for in-hospital mortality. However, inflammation in general seems to be more important than pneumonia itself for long-term prognosis. Compared to community-acquired pneumonia studies, C-reactive protein levels were rather low and therefore pneumonia might be over-diagnosed in ADHF patients.

Community-acquired pneumonia in primary care: clinical assessment and the usability of chest radiography

OBJECTIVES

To investigate the diagnostic value of different clinical and laboratory findings in pneumonia and to explore the association between the doctor's degree of suspicion and chest X-ray (CXR) result and to evaluate whether or not CXR should be used routinely in primary care, when available.

DESIGN

A three-year prospective study was conducted between September 2011 and December 2014.

SETTING

Two primary care settings in Linköping, Sweden.

SUBJECTS

A total of 103 adult patients with suspected pneumonia in primary care.

MAIN OUTCOME MEASURES

The physicians recorded results of a standardized medical physical examination, including laboratory results, and rated their suspicion into three degrees. The outcome of the diagnostic variables and the degree of suspicion was compared with the result of CXR.

RESULTS

Radiographic pneumonia was reported in 45% of patients. When the physicians were sure of the diagnosis radiographic pneumonia was found in 88% of cases (p < 0.001), when quite sure the frequency of positive CXR was 45%, and when not sure 28%. Elevated levels of C-reactive protein (CRP) ≥ 50mg/L were associated with the presence of radiographic pneumonia when the diagnosis was suspected (p < 0.001).

CONCLUSION

This study indicates that CXR can be useful if the physician is not sure of the diagnosis, but when sure one can rely on one's judgement without ordering CXR.

KEY POINTS

There are different guidelines but no consensus on how to manage community-acquired pneumonia in primary care. When the physician is sure of the diagnosis the judgement is reliable without chest X-ray and antibiotics can be safely prescribed. Chest X-ray can be useful in the assessment of pneumonia in primary care, when the physician is not sure of the diagnosis.

Clinical and Laboratory Findings in Patients With Acute Respiratory Symptoms That Suggest the Necessity of Chest X-ray for Community-Acquired Pneumonia

Background:

Pneumonia is a common illness in all parts of the world and is considered as a major cause of death among all age groups. Nevertheless, only about 5% of patients referring to their primary care physicians with acute respiratory symptoms will develop pneumonia.

Objectives:

This study was performed to derive practical criteria for performing chest radiographs for the evaluation of community-acquired pneumonia (CAP).

Patients and Methods:

A total of 420 patients with acute respiratory symptoms and positive findings on chest radiograph were evaluated from December 2008 to December 2009. The subjects were referred to outpatient clinics or emergency departments of Birjand's medical university hospitals, Iran, and were enrolled as positive cases. A checklist was completed for each patient including their demographic information, clinical signs and symptoms (cough, sputum production, dyspnea, chest pain, fever, tachycardia, and tachypnea), abnormal findings in pulmonary auscultation and laboratory findings (erythrocyte sedimentation rate, C-reactive protein levels, and white blood cell count). An equal number of age-matched individuals with acute respiratory symptoms, but insignificant findings on chest radiography, were included as the control group. Finally, the diagnostic values of different findings were compared.

Results:

The data showed that vital signs and physical examination findings are useful screening parameters for predicting chest radiograph findings in outpatient settings. Therefore, by implementing a prediction rule, we would be able to determine which patients would benefit from a chest X-Ray (sensitivity, 94% and specificity, 57%).

Conclusions:

This study's findings suggest that requesting chest radiographs might not be necessary in patients with acute respiratory symptoms unless the vital signs and/or physical examination findings are abnormal. Considering the 94% sensitivity of this rule for predicting CAP, a chest radiograph is required for patients with unreliable follow-ups or moderate to high likelihood of morbidity if CAP is not initially detected.

Imaging of Pulmonary Infections

Pulmonary infection is one of the most frequent causes of morbidity and mortality throughout the world. Many infections occur in individuals with concomitant intrapulmonary or extrathoracic diseases; however, they commonly develop in otherwise healthy people. In the non-immunocompromised population, pneumonia is the most prevalent community-acquired infection and the second most common nosocomial infectious disorder. In immunocompromised patients, in children, and in the elderly, pneumonia, as well as other pulmonary infections, may develop into a life-threatening condition.

Inhaled corticosteroids and pneumonia in chronic obstructive pulmonary disease

Inhaled corticosteroids are widely used in chronic obstructive pulmonary disease (COPD) and, in combination with long-acting β2 agonists, reduce exacerbations and improve lung function and quality of life. However, inhaled corticosteroids have been linked with an increased risk of pneumonia in individuals with COPD, but the magnitude of this risk, the effects of different preparations and doses, and the mechanisms of this effect remain unclear. Therefore, making informed clinical decisions--balancing the beneficial and adverse effects of inhaled corticosteroids in individuals with COPD--is difficult. Understanding of the mechanisms of increased pneumonia risk with inhaled corticosteroids is urgently needed to clarify their role in the management of COPD and to aid the development of new, safer therapies.

The diagnosis of pneumonia requires a chest radiograph (x-ray)-yes, no or sometimes?

Community-acquired pneumonia (CAP) remains a common condition associated with considerable morbidity and mortality. Outcome is improved by early recognition and rapid institution of empirical antibiotic therapy. A number of international guidelines recommend a chest radiograph (x-ray) is obtained when pneumonia is suspected; the argument forwarded is that chest radiographs are relatively inexpensive and enable pneumonia (lung consolidation) to be confirmed or excluded. But, radiographs are not available in the community setting and introduce a delay in diagnosis and treatment. For these reasons, in mild CAP treated by primary care, guidelines suggest criteria for clinical diagnosis. However, there is debate as to whether clinical features alone are sufficiently reliable to support a diagnosis of CAP with some suggesting diagnostic precision is improved by chest radiographs. Conversely, several studies have demonstrated a lack of agreement in the interpretation of chest radiographs bringing their role as the ultimate arbiter of diagnosis into question. Below we debate the diagnostic role of the humble chest radiograph in the context of suspected CAP.

Pneumonia in hemodialysis patients: a challenging diagnosis in the emergency room

BACKGROUND

Diagnosing pneumonia in hemodialysis patients is challenging. We hypothesized that pulmonary edema, which occurs commonly in hemodialysis patients, may frequently be misdiagnosed as pneumonia.

METHODS

We retrospectively reviewed the records of 105 hemodialysis patients admitted with the diagnosis of pneumonia. Two experienced radiologists masked to the clinical course and subsequent imaging, independently interpreted the admission chest radiographs. In 68 of the patients, 2 internists independently reviewed the hospitalization records to diagnose pneumonia and pulmonary edema. The level of agreement among the radiologists was assessed using the kappa test. Using the clinical diagnoses, chest radiograph attributes were calculated. Logistic regression was performed to identify clinical and laboratory markers associated with pneumonia and pulmonary edema.

RESULTS

The radiologist showed slight agreement on pneumonia (κ = 0.32) and pulmonary edema (κ = 0.28). Using clinical consensus, pneumonia was diagnosed in only 21% (14/68) of patients. Chest radiograph attributes for diagnosing pneumonia included: sensitivity 50%, specificity 58%, positive predictive value 25% and negative predictive value 81%. Pneumonia was associated with presenting temperature (odds ratio [OR] = 
2.01; 95% CI, 1.03-3.93). Pulmonary edema was associated with shortness of breath (SOB) at admission 
(OR = 4.83; 95% CI, 1.25-18.6), presenting temperature (OR = 0.44; 95% CI, 0.21-0.92) and volume removed during hemodialysis (OR = 1.96; 95% CI, 1.16-3.31).

CONCLUSIONS

The admission chest radiograph has significant limitations when used to diagnose pneumonia in hemodialysis patients. A high presenting temperature supports the diagnosis of pneumonia, while a low presenting temperature, SOB and large volume ultrafiltration favor the diagnosis of pulmonary edema.

Diagnosis and management of pneumonia and bronchitis in outpatient primary care practices

AIMS

To understand which clinical criteria physicians use to diagnose pneumonia compared to bronchitis and upper respiratory tract infection (URTI).

METHODS

Retrospective chart review of adults diagnosed with pneumonia, bronchitis, or URTI.

RESULTS

Logistic regression analysis identified rales, a temperature > 100 degrees F (37.8 degrees C), chest pain, dyspnoea, rhonchi, heart rate, respiratory rate, and rhinorrhoea, as the best explanation for the variation in diagnosis of pneumonia compared to either of the alternative diagnoses (R2 = 59.3), with rales and a temperature > 100 degrees F explaining 30% of the variation. Rales, chest pain, and a temperature > 100 degrees F best predicted the ordering of a chest x-ray (R2 = 20.0). However, 35% (59/175) of patients diagnosed with pneumonia had a negative chest x-ray. Abnormal breath sounds were the best predictors for prescribing antibiotics (R2 = 38%). A significant number of patients with acute bronchitis (93% excluding sinusitis) and URTI (42%) were given antibiotics.

CONCLUSIONS

The presence of abnormal breath sounds and a temperature > 100 degrees F were the best predictors of a diagnosis of pneumonia.

Microfluidic platform versus conventional real-time polymerase chain reaction for the detection of Mycoplasma pneumoniae in respiratory specimens

Rapid, accurate diagnosis of community-acquired pneumonia (CAP) due to Mycoplasma pneumoniae is compromised by low sensitivity of culture and serology. Polymerase chain reaction (PCR) has emerged as a sensitive method to detect M. pneumoniae DNA in clinical specimens. However, conventional real-time PCR is not cost-effective for routine or outpatient implementation. Here, we evaluate a novel microfluidic real-time PCR platform (Advanced Liquid Logic, Research Triangle Park, NC) that is rapid, portable, and fully automated. We enrolled patients with CAP and extracted DNA from nasopharyngeal wash (NPW) specimens using a biotinylated capture probe and streptavidin-coupled magnetic beads. Each extract was tested for M. pneumoniae-specific DNA by real-time PCR on both conventional and microfluidic platforms using Taqman probe and primers. Three of 59 (5.0%) NPWs were positive, and agreement between the methods was 98%. The microfluidic platform was equally sensitive but 3 times faster and offers an inexpensive and convenient diagnostic test for microbial DNA.

[Critical evaluation and predictive value of clinical presentation in out-patients with acute community-acquired pneumonia]

Diagnostic probability of community-acquired pneumonia (CAP) depends on data related to age and clinical and radiological findings. The critical evaluation of data in the literature leads to the following conclusions: 1) the prevalence of CAP in a given population with acute respiratory disease is 5% in outpatients and 10% in an emergency care unit. This could be as low as 2% in young people and even higher than 40% in hospitalized elderly patients; 2) the collection of clinical data is linked to the way the patient is examined and to the expertise of the clinician. The absolute lack of "vital signs" has a good negative predictive value in CAP; presence of unilateral crackles has a good positive predictive value; 3) there is a wide range of X-ray abnormalities: localized alveolar opacities; interstitial opacities, limited of diffused. The greatest radiological difficulties are encountered in old people with disorders including chronic respiratory or cardiac opacities and as a consequence of the high prevalence of bronchopneumonia episodes at this age; 4) among patients with lower respiratory tract (LRT) infections, the blood levels of leukocytes, CRP and procalcitonine are higher in CAP patients, mainly when their disease has a bacterial origin. Since you have not a threshold value reliably demonstrated in large populations with LRT infections or acute respiratory disease, presence or absence of these parameters could only be taken as a slight hint for a CAP diagnosis.

Epidemiological survey on incidence and treatment of community acquired pneumonia in Italy

STUDY OBJECTIVES

To estimate annual incidence of community acquired pneumonia (CAP) in an Italian general population sample.

DESIGN AND PARTICIPANTS

Two hundred and eighty-seven family practitioners (64.6% of those selected) recorded suspected or ascertained CAP cases for 1 year. Information on smoking habit, respiratory symptoms and signs, co-morbidity, antibiotic and corticosteroid therapy, hospitalization, mortality and recovery were obtained.

RESULTS

Six hundred and ninety-nine case forms were collected (53.1% females, mean age 59.6+/-19.5, 20.6% smokers). CAP incidence rates per 1000 population were: 1.69 in men vs. 1.71 in women; 2.33 in the North vs. 1.29 in the Centre-South of Italy; between 0.73 in 14-, and 3.34 in 64+year-old subjects. Main symptoms and signs were cough (73.3%), crackles (72.8%), dullness (57.3%), asthenia (53.4%). 59.5% of subjects had concurrent diseases, mostly cardiac and respiratory. 77.2% of cases had chest X-ray (with parenchymal density in 90.6%). Phlegm microbiological examination was performed in 12.8% of cases. First choice antibiotics were cephalosporins (45.8%), macrolides (20.2%), other beta-lactams (18.6%), and fluoroquinolones (12.2%). Rates of hospitalization and of mortality were 31.8% and 6.0%, respectively.

CONCLUSION

This study confirmed that the annual CAP incidence rate in the general population of South Europe is about 2 per 1000 population and showed a wide choice of antibiotic treatment.

Reliability of radiographic findings and the relation to etiologic agents in community-acquired pneumonia

In a clinical setting the chest radiograph is the reference standard in establishing the diagnosis of community-acquired pneumonia (CAP). This study aimed to assess interobserver reliability (IR) of radiographic findings and the relationship to different causative pathogens in CAP. Chest radiographs of 192 patients with pneumonia, obtained from a database, were reviewed by 2 radiologists and 1 respiratory physician without specific clinical information. Main pattern of infiltrate, extent of pneumonia, presence of pleural fluid, thickened bronchial walls, lymphadenopathy and air bronchogram were scored. Also, the involved lobes were identified. Sputum cultures, blood cultures and serological tests were performed to identify the causative pathogen. IR was poor (kappa <0.4) for determining the main pattern of infiltrate and presence of air bronchogram, lymphadenopathy and thickening of bronchial walls. IR was fair to good (kappa 0.4-0.7) or even excellent (kappa>0.7) for determining the presence of pleural effusion, the extent of pneumonia and for identifying the lobes involved. Mycoplasma pneumoniae was associated more often with patchy alveolar opacities than Streptococcus pneumoniae (P=0.05). Chlamydia spp. were associated with unilobar involvement (86%), especially when compared to M. Pneumoniae (P=0.03) and S. pneumoniae (P=0.004). In conclusion, simple features such as presence of pleural fluid, the extent of pneumonia and identifying the involved lobes show fair to excellent IR. Other features such as main pattern of infiltrate are difficult to assess and show poor IR. Hardly any relation between different pathogens and radiological features was found. Therefore, chest radiographs are of limited value in predicting the causative pathogen, but are of good use to determine the extent of pneumonia and to detect complications such as parapneumonic effusion.