[Antibiotic treatment of community-acquired and hospital-acquired pneumonia]

Community-acquired and nosocomial bacterial pneumonia are among the most common infectious diseases in Germany. Knowledge of possible pathogens and therapeutic implications thereof are essential to be able to provide adequate, differentiated antimicrobial therapy with the appropriate drugs, form of application, dose, and duration. New diagnostics that include multiplex polymerase chain reaction, correct interpretation of the biomarker procalcitonin, and treatment of multidrug-resistant bacteria are becoming increasingly import.

Intracellular pyruvate levels positively correlate with cytokine production capacity in tolerant monocytes from patients with pneumonia

BACKGROUND

Community-acquired pneumonia (CAP) is responsible for a high morbidity and mortality worldwide. Monocytes are essential for pathogen recognition and the initiation of an innate immune response. Immune cells induce intracellular glycolysis upon activation to support several functions.

OBJECTIVE

To obtain insight in the metabolic profile of blood monocytes during CAP, with a focus on glycolysis and branching metabolic pathways, and to determine a possible association between intracellular metabolite levels and monocyte function.

METHODS

Monocytes were isolated from blood of patients with CAP within 24 h of hospital admission and from control subjects matched for age, sex and chronic comorbidities. Changes in glycolysis, oxidative phosphorylation (OXPHOS), tricarboxylic acid (TCA) cycle and the pentose phosphate pathway were investigated through RNA sequencing and metabolomics measurements. Monocytes were stimulated ex vivo with lipopolysaccharide (LPS) to determine their capacity to produce tumor necrosis factor (TNF), interleukin (IL)-1β and IL-10.

RESULTS

50 patients with CAP and 25 non-infectious control subjects were studied. When compared with control monocytes, monocytes from patients showed upregulation of many genes involved in glycolysis, including PKM, the gene encoding pyruvate kinase, the rate limiting enzyme for pyruvate production. Gene set enrichment analysis of OXPHOS, the TCA cycle and the pentose phosphate pathway did not reveal differences between monocytes from patients and controls. Patients' monocytes had elevated intracellular levels of pyruvate and the TCA cycle intermediate α-ketoglutarate. Monocytes from patients were less capable of producing cytokines upon LPS stimulation. Intracellular pyruvate (but not α-ketoglutarate) concentrations positively correlated with IL-1β and IL-10 levels released by patients' (but not control) monocytes upon exposure to LPS.

CONCLUSION

These results suggest that elevated intracellular pyruvate levels may partially maintain cytokine production capacity of hyporesponsive monocytes from patients with CAP.

Pulmonary Infections, Including Ventilator-Associated Pneumonia

Pneumonia is a leading cause of morbidity and mortality and a primary cause of hospitalizations. Guidelines have been established through the American Thoracic Society and Infectious Diseases Society of America in 2016 focusing on the causative pathogen for antibiotic selection. In 2017 an International European task force provided guidelines of specific antibiotic selections based on drug resistance and mortality risk. Improving patient outcomes is based not only on the appropriate treatment, which should not be delayed, but also on implementation and adherence to evidence-based strategies to reduce the increased risk of mortality.

Community-acquired pneumonia: Trends in and research on drug resistance and advances in new antibiotics

Community-acquired pneumonia (CAP) refers to infectious inflammation of the lung parenchyma developing outside of a hospital. CAP has quite a high mortality and morbidity rate worldwide, and especially among elderly patients. The increasing burden of CAP is due to antibiotic resistance, the growth of the elderly population, and underlying comorbidities. Streptococcus pneumoniae remains the most common bacterial pathogen causing CAP, but multi-drug resistance bacteria and potential pathogens have increased the difficulty and challenges of managing CAP. Although preventive measures, diagnostic techniques, and treatment strategies are constantly advancing and improving, the susceptibility of multi-drug resistant pathogens, such as including Methicillin-Resistant Staphylococcus aureus (MRSA), Klebsiella pneumoniae, and Pseudomonas aeruginosa, has not improved significantly in recent decades, thus highlighting the importance and necessity of developing new antibiotics for the treatment of CAP. New antimicrobials have been approved over the past few years that will expand treatment options for CAP, and especially for patients with potential comorbidities. This situation also offers the chance to reduce the abuse of antibiotics, their toxicities, and their adverse reactions and to provide effective personalized antibiotic treatment.

Automatically discriminating and localizing COVID-19 from community-acquired pneumonia on chest X-rays

The COVID-19 outbreak continues to threaten the health and life of people worldwide. It is an immediate priority to develop and test a computer-aided detection (CAD) scheme based on deep learning (DL) to automatically localize and differentiate COVID-19 from community-acquired pneumonia (CAP) on chest X-rays. Therefore, this study aims to develop and test an efficient and accurate deep learning scheme that assists radiologists in automatically recognizing and localizing COVID-19. A retrospective chest X-ray image dataset was collected from open image data and the Xiangya Hospital, which was divided into a training group and a testing group. The proposed CAD framework is composed of two steps with DLs: the Discrimination-DL and the Localization-DL. The first DL was developed to extract lung features from chest X-ray radiographs for COVID-19 discrimination and trained using 3548 chest X-ray radiographs. The second DL was trained with 406-pixel patches and applied to the recognized X-ray radiographs to localize and assign them into the left lung, right lung or bipulmonary. X-ray radiographs of CAP and healthy controls were enrolled to evaluate the robustness of the model. Compared to the radiologists' discrimination and localization results, the accuracy of COVID-19 discrimination using the Discrimination-DL yielded 98.71%, while the accuracy of localization using the Localization-DL was 93.03%. This work represents the feasibility of using a novel deep learning-based CAD scheme to efficiently and accurately distinguish COVID-19 from CAP and detect localization with high accuracy and agreement with radiologists.

Community-Acquired Pneumonia: A Focused Review

Community-acquired pneumonia (CAP) is a common cause for admission to the hospital and contributes significantly to patient morbidity and healthcare cost. We present a review of the epidemiology, pathophysiology, risk factors, symptoms, diagnosis, presentations, risk-stratification, markers, and management of CAP in the United States (US). The overall incidence of CAP is 16 to 23 cases per 1000 persons per year, and the rate increases with age. Some of the risk factors for CAP include comorbidities such as, chronic obstructive pulmonary disease (COPD), asthma, and heart failure. CAP symptoms vary, and typically include productive cough, dyspnea, pleuritic pain, abnormal vital signs (e.g., fever, tachycardia), and abnormal lung examination findings. A diagnosis can be made by radiography, which has the additional benefit of helping to identify patterns associated with typical and atypical CAP. There are risk-stratification calculators that can be used routinely by physicians to triage patients, and to determine adequate management. The Infectious Diseases Society of America (IDSA) and the American Thoracic Society (ATS) developed the Pneumonia Severity Index (PSI) which incorporates 20 risk factors to place patients into 5 classes correlated with mortality risk. In addition, the British Thoracic Society (BTS) established the original severity score CURB (confusion, uremia, respiratory rate, low blood pressure) to identify patients with CAP who may be candidates for outpatient vs. inpatient treatment. Inflammatory markers, such as procalcitonin (PCT), can be used to guide management throughout hospital stay. Antibiotic coverage will vary depending on whether outpatient vs. inpatient management is required.

Risk prediction of in-hospital mortality among patients with type 2 diabetes mellitus and concomitant community-acquired pneumonia

BACKGROUND

The aim of the present study was to investigate the risk factors for in-hospital mortality among patients with type 2 diabetes mellitus (T2DM) and concomitant community-acquired pneumonia (CAP) and establish a risk prediction score.

METHODS

Data from 1,360 adult patients with T2DM and concomitant CAP hospitalized in two grade 3A hospitals between 2009 and 2019 were collected through electronic medical records. Data obtained included the status of diabetes mellitus, comorbidities, laboratory and imaging findings, and treatment outcomes. Statistical analysis was conducted to investigate the risk factors affecting prognosis, and a clinical risk prediction score was designed.

RESULTS

Based on the patients' treatment outcomes (deceased, improved and cured), the cohort was divided into two groups: deceased and improved; 16 parameters were significant after segmentation. However, the following nine parameters were independent predictors of mortality: neutrophil-lymphocyte ratio (NLR) ≥4, pulse rate ≥125 bpm, change in state of consciousness, arterial blood pH ≤7.35, age ≥65 years, serum sodium ≤130 mmol/L, initial fasting blood glucose ≥9 mmol/L, multilobar involvement, and diabetic nephropathy. Based on these findings, a risk prediction score was established, and bootstrap validation was performed. The risk prediction score was significantly superior to CURB-65 [confusion, urea >7 mmol/L, respiratory rate >30/min, low blood pressure (systolic <90 mmHg or diastolic <60 mmHg), age >65 years] and slightly superior than the pneumonia severity index (PSI).

CONCLUSIONS

The influencing factors for in-hospital mortality among patients with T2DM and concomitant CAP included advanced age, change in state of consciousness, increased pulse rate, acidosis, high NLR, high platelet-lymphocyte ratio, hyponatremia, hyperglycemia, and diabetic nephropathy. These parameters should be recognized in clinical practice, with active interventions to improve the treatment success rate. The risk prediction score effectively differentiated the mortality risk of inpatients, thereby providing guidance on clinical decision-making.

Dynamic change of Mycoplasma pneumoniae pneumonia in hospitalized children in a general hospital: a 3-year retrospective analysis

BACKGROUND

The epidemiology and economic burden of hospitalized community-acquired pneumonia (CAP) children due to MP is still poorly understood. This study aimed to investigate the dynamic changes of Mycoplasma pneumoniae pneumonia (MPP) in children in a general hospital.

METHODS

A total of 2011 CAP children aged 1-16 years hospitalized at Peking University Third Hospital from 2017 to 2019 were enrolled by cross-sectional study for the retrospective analysis of the clinical data mainly including seasonal distribution of MPP, hospital stay, severity, complications, use of flexible bronchoscopy, and hospitalization costs. The dynamic changes of CAP and MPP children within 3 consecutive years and the differences between the MPP group and non-MPP groups were compared.

RESULTS

The proportion of CAP children among hospitalized children was 32.4%, 38.5%, and 39.5% in 2017, 2018, and 2019, respectively, showing an upward trend (P<0.05).The prevalence rate of MPP was highest in the third quarter (30.2%) and the fourth quarter (39.2%) and lowest in the second quarter (13.2%) (χ²=51.8, P<0.05). Compared with the non-MPP group, the MPP group had significantly higher incidence of severe pneumonia (19.4% vs. 12.0%, χ²=20.99), incidence of complications (16.1% vs. 6.5%, χ²=48.24), proportion of patients undergoing flexible bronchoscopy (38.4% vs. 9.0%, χ²=252.79), and hospitalization costs (all P<0.05), along with significantly longer hospital stay (6 vs. 4 days, z=-11.131). A dynamic comparison of the clinical characteristics of MPP in 3 years showed that the number of children with MPP increased significantly in preschoolers in 2018 (37.3%) and in school-aged or older children in 2019 (53%) (P<0.05). MPP peaks occurred in August 2018 and November 2019. The total hospitalization costs, examination fees, and non-medication treatment costs increased significantly (the z values were 35.24, 46.79, and 9.64, respectively; P<0.05) year by year among MPP children; there was no significant difference in the medication cost over these 3 years (z=4.81, P>0.05).

CONCLUSIONS

The proportions of severe pneumonia, complications, and use of flexible bronchoscopy as well as the hospitalization days and costs are higher in MPP children. General hospitals should develop integrated clinical quality control programs for MPP children, so as to optimize the allocation of medical resources.

Early diagnosis and appropriate respiratory support for Mycoplasma pneumoniae pneumonia associated acute respiratory distress syndrome in young and adult patients: a case series from two centers

BACKGROUND

Mycoplasma pneumoniae (M. pneumoniae) is one of the most common causes of community acquired pneumonia (CAP). Establishing an early diagnosis of M. pneumoniae pneumonia in patients with acute respiratory distress syndrome (ARDS) may have important therapeutic implications.

METHODS

We describe diagnosis and management of M. pneumoniae pneumonia induced ARDS in a case series of adults and youth hospitalized with radiographically confirmed CAP prospectively enrolled in an observational cohort study in two university teaching hospitals, from November 2017 to October 2019.

RESULTS

In all 10 patients, early and rapid diagnosis for severe M. pneumoniae pneumonia with ARDS was achieved with polymerase chain reaction (PCR) or metagenomic next-generation sequencing (mNGS) testing of samples from the lower respiratory tract or pleural effusion. The average PaO₂/FiO₂ of all patients was 180 mmHg. Of the 10 cases, 4 cases had moderate ARDS (100 mmHg ≤ PaO₂/FiO₂ < 200 mmHg) and 3 cases had severe ARDS (PaO₂/FiO₂ < 100 mmHg). High flow nasal cannula (HFNC) was applied in all patients, though only two patients were sufficiently supported with HFNC. Invasive mechanical ventilation (IMV) was required in 5 patients. High resistance (median 15 L/cmH₂O/s) and low compliance (median 38 ml/cmH₂O) was observed in 4 cases. In these 4 cases, recruitment maneuvers (RM) were applied, with 1 patient demonstrating no response to RM. Prone positioning were applied in 4 cases. Two cases needed ECMO support with median support duration of 5.5 days. No patient in our case series received corticosteroid therapy. All patients were survived and were discharged from hospital.

CONCLUSIONS

Early and rapid diagnosis of severe M. pneumoniae pneumonia with ARDS can be achieved with PCR/mNGS tests in samples from the lower respiratory tract or pleural effusion. In our case series, half of M. pneumoniae pneumonia induced ARDS cases were adequately supported with HFNC or NIV, while half of cases required intubation. RM and prone position were effective in 30% of intubated cases, and 20% needed ECMO support. When early anti-mycoplasmal antibiotics were given together with sufficient respiratory support, the survival rate was high with no need for corticosteroid use.

Initial diagnosis and management of adult community-acquired pneumonia: a 5-day prospective study in Shanghai

Background

Despite the release of a national guideline in 2016, the actual practices with respect to adult community-acquired pneumonia (CAP) remain unknown in China. We aimed to investigate CAP patient management practices in Shanghai to identify potential problems and provide evidence for policy making.

Methods

A short-period, 5-day prospective cross-sectional study was performed with sampled pulmonologists from 36 hospitals, encompassing all the administrative districts of Shanghai, during January 8–12, 2018. The medical information was recorded and analyzed for the patients with the diagnosis of CAP who were cared for by 46 pulmonologists during the study period.

Results

Overall, 435 patients were included in the final analysis, and 94.3% had a low risk of death in terms of CRB-65 criteria (C: disturbance of consciousness, R: respiratory rate, B: blood pressure, 65: age). When diagnosed with CAP, 70.1% of patients were not evaluated using the CURB-65 score (CRB-65 + U: urea nitrogen), but most patients (95.4%) were evaluated using CRB-65. Time to achieve clinical stability was longer in patients with hypoxemia than in those without hypoxemia (8.42±6.36 vs. 5.53±4.12 days, P=0.004). Overall, 84.4% of patients with a CRB-65 score of 0 were administered antibiotics intravenously, and 19.4% were still hospitalized after excluding hypoxemia and comorbidities. The average duration of antibiotic treatment was 10.4±4.9 days. Overall, 72.6% of patients received antibiotics covering atypical pathogens whose time to clinical stability was significantly shortened compared with those without coverage, but the antibiotic duration was similar and not correspondingly shortened.

Conclusions

CRB-65 seems to be more practical than CURB-65 for the initial evaluation of CAP in the context of local practice, and oxygenation assessment should be included in the evaluation of severity. Overtreatment may be relatively common in patients at low risk of death, including unreasonable hospitalization, intravenous administration, and antibiotic duration.

Rates of hospitalization for community-acquired pneumonia among US adults: A systematic review

BACKGROUND

Community-acquired pneumonia (CAP) is associated with significant disease burden in adults but has not been measured uniformly. Reconciling differences across studies is critical for understanding the true burden of CAP.

METHODS

We performed a systematic literature review of the incidence of hospitalized CAP among US adults and described the impact of key study characteristics on these estimates.

RESULTS

After review of 8361 articles as of January 31, 2019, we identified 28 studies with 41 unique estimates of hospitalized CAP incidence. Among adults ≥65 years of age, annual rates of hospitalized CAP ranged from 847 to 3500 per 100,000 persons with median = 1830. Rates were lower in studies that excluded patients with healthcare-associated (but community-onset) pneumonia (HCAP; median = 2003 vs 1286; P = 0.02) or immunocompromising conditions (median = 1895 vs 1409; P = 0.27) compared to those that did not. Rates of CAP were also lower in studies that used more restrictive criteria for diagnosing pneumonia (eg, pneumonia coded in any diagnosis position [median = 2270] vs pneumonia coded in the first position only [median = 1375] in studies of administrative claims; P = 0.02). For adults <65 years of age, rates of CAP were lower (range: 89 to 1138 per 100,000; median = 199).

CONCLUSIONS

CAP causes a significant disease burden among adults, particularly among those ≥65 years of age. Commonly-applied exclusion criteria (eg, persons with HCAP or immunocompromising conditions) or restrictive case definitions (eg, only including pneumonias coded in the primary diagnosis position) have led to systematic underestimation of CAP incidence in many previous studies. In studies that did not apply these restrictive criteria, the rate of hospitalization was approximately 2000 per 100,000 annually. Understanding the true burden of adult CAP is critical for highlighting the ongoing need for expanded prevention programs, including vaccination.

Lactate dehydrogenase as a prognostic marker of renal transplant recipients with severe community-acquired pneumonia: a 10-year retrospective study

BACKGROUND

Lactate dehydrogenase (LDH) is an easily accessible biological marker that has been associated with several pulmonary disorders. The aim of this study was to investigate the prognostic value of serum LDH in renal transplant recipients with severe community-acquired pneumonia (CAP).

METHODS

A total of 77 renal transplant recipients with severe CAP admitted to the intensive care unit (ICU) were screened for eligibility in this retrospective study. Patient characteristics and laboratory tests, such as LDH on day 1 (LDH_{day 1}) and day 3 (LDH_{day 3}) were recorded. Cox regression models were used to assess the performance of LDH to predict 90-day mortality.

RESULTS

Median LDH level was higher on day 1 in 90-day nonsurvivors (440 U/L, IQR, 362-1,055 U/L) than in survivors (334 U/L, IQR, 265-432 U/L; P<0.001); median LDH level on day 3 in nonsurvivors was 522.5 U/L (IQR, 457.5-1,058.5 U/L) and in survivors 290 U/L (IQR, 223-387.5 U/L; P<0.001). Analysis of LDH kinetics from day 1 to day 3 showed an increase in nonsurvivors and a decrease in survivors. Moreover, Multivariate Cox analysis showed that LDH_{day 1} (increase per 100 U/L), LDH_{day 3} (increase per 100 U/L) and LDH kinetics (increase per 10%) were independently associated with 90-day mortality.

CONCLUSIONS

Serum LDH levels and LDH kinetics early were independently associated with 90-day mortality in renal transplant recipients with severe CAP. In future, the prognostic role of LDH needs to be warranted.

Streptococcus pneumoniae serotype 3 is masking PCV13-mediated herd immunity in Canadian adults hospitalized with community acquired pneumonia: A study from the Serious Outcomes Surveillance (SOS) Network of the Canadian immunization research Network (CIRN)

BACKGROUND

The 13-valent pneumococcal conjugate vaccine (PCV13) was recently shown to be effective against PCV13-type invasive pneumococcal disease (IPD) and pneumococcal community acquired pneumonia (CAP_Spn) in healthy adults aged ≥65 years, prompting many countries to re-assess adult immunization. In Canada, the potential benefits of adult PCV13 immunization were unclear given anticipated herd immunity from PCV13 childhood immunization introduced since 2010. This study describes the serotype distribution and clinical outcomes of Canadian adults aged ≥16 years, who were hospitalized with CAP_Spn and IPD from 2010 to 2015.

METHODS

Active surveillance for CAP and IPD was performed in adult hospitals across five Canadian provinces. IPD was identified when Streptococcus pneumoniae was isolated from sterile sites. Bacteremic and non-bacteremic CAP_Spn were identified using blood culture, and sputum culture or PCV13-specific urine antigen detection (UAD_PCV13), respectively. Serotype was assigned using Quellung reaction, PCR, or UAD_PCV13.

RESULTS

Of 6687 CAP cases where a test was performed, S. pneumoniae positivity decreased from 15.9% in 2011 to 8.8% in 2014, but increased to 12.9% in 2015. CAP_Spn attributed to PCV13 serotypes followed a similar trend, dropping from 8.3% in 2010 to 4.6% in 2014, but increasing to 6.3% in 2015. The decline was primarily attributed to serotypes 7F and 19A, and the proportional increase to serotype 3. Similar trends were noted for bacteremic and non-bacteremic CAP_Spn. Serious outcomes such as 30-day mortality, intensive care unit admission, and requirement for mechanical ventilation were prominent in CAP_Spn and IPD cases, but remained unchanged over the study years.

CONCLUSION

Herd immunity afforded primarily by serotypes 7F and 19A appears to be partly masked by a concomitant proportional increase of serotype 3. Despite evidence of herd immunity, these PCV13 serotypes remain persistent in Canadian adults hospitalized with CAP_Spn, and represent between 5 and 10% of all CAP in this patient population.

Relationship between pneumonia and cardiovascular diseases: A retrospective cohort study of the general population

AIMS

To evaluate the relationship between cardiovascular diseases (CVDs) and pneumonia in the general population.

METHODS

This retrospective observational study included two cohorts, namely CVD (n = 28,363) and non-CVD (n = 28,363) cohorts, which were matched by propensity score and examined for cases of pneumonia. Data were obtained from 2000 to 2011. In both cohorts, pneumonia risk was measured using multivariable Cox proportional hazard models.

RESULTS

With the non-CVD cohort as reference, the corresponding adjusted hazard ratios (aHRs) [95% confidence intervals (CIs)] of pneumonia were 2.03 [1.77-2.31] for coronary artery disease, 4.11 [3.15-5.36] for heart failure, 3.21 [2.70-3.81] for cerebrovascular disease, 1.46 [1.07-1.98] for peripheral vascular disease, and 2.27 [2.01-2.56] for the CVD cohort. The cohort with comorbidities had a higher risk (all p < .05) of pneumonia compared with that without comorbidities, except for patients with the comorbidities of hypertension, hyperlipidemia, obesity, and liver disease. The aHR (95% CI) of pneumonia for antibiotic use was 1.26 (1.09-1.47). The aHRs of community-acquired pneumonia (CAP) and hospital-acquired pneumonia (HAP) were 3.25 (95% CI = 1.04-10.1) and 2.95 (95% CI = 2.25-3.88), respectively. The aHRs (95% CI) were 1.78 (1.05-3.03) for intensive care unit (ICU) risk and 0.98 (0.96-0.99) for length of admission.

CONCLUSION

Pneumonia risk was associated with CVDs, especially heart failure, regardless of age, gender, comorbidities, and antibiotic use, particularly in elderly male patients. In addition, Patients with CVDs had a higher risk of CAP and HAP. The CVD cohort had a higher frequency of ICU admissions, but shorter admission lengths.

Distribution of the atypical pathogens of community-acquired pneumonia to disease severity

Background

To investigate the epidemiological characteristics of 11 atypical pathogens of community-acquired pneumonia (CAP) among Chinese, and to determine whether or not there is an association between these pathogens and the severity of illness.

Methods

We conducted a surveillance study for CAP in 30 hospitals of Beijing. Epidemiological data and clinical specimens were systematically collected from enrolled CAP patients. The detection for 11 atypical pathogens [9 respiratory viruses, Mycoplasma pneumoniae (MP) and Chlamydophila pneumoniae (CP)] was performed. Risk factors of severe CAP and death in Hospital were evaluated.

Results

A total of 6,008 CAP patients [including 1,071 severe CAP (SCAP)] were enrolled. The overall detection rate of the 11 atypical pathogens was 42.4% among 1,925 child CAP (39.9% among 274 child SCAP), and 25.8% among 4,083 adult CAP (22.8% among 797 adult SCAP). The most frequent atypical pathogen among child SCAP was parainfluenza virus (10.2%) followed by respiratory syncytial virus (RSV) (8.4%). However, the most frequent atypical pathogen among adult SCAP was influenza virus (8.9%) followed by parainfluenza virus (3.8%). Multivariate analyses showed that the important predictors for SCAP were an age ≤9 years, an age ≥65 years and co-existing diseases. These factors, except an age ≤9 years, were also predictors of death in Hospital. None of these 11 atypical pathogens was included as the risk factors of SCAP or death in Hospital.

Conclusions

Although these 11 atypical pathogens were the common causes of CAP (including SCAP) among Chinese, they were not observed to increase risks for SCAP or death in Hospital.

The Use of Statins and Risk of Community-Acquired Pneumonia

PURPOSE OF THE REVIEW

Community-acquired pneumonia (CAP) is still associated with a large burden and causes significant morbidity and mortality. Besides universal vaccination and antibiotic treatment, statins as adjunctive therapy may also have a beneficial role in the prevention and treatment of CAP. Our goal from this review is to discuss the epidemiology of CAP, and role of statins as adjunctive therapy in the development of CAP.

RECENT FINDINGS

Statins are lipid-lowering medications characterized by their ability to control hypercholesterolemia in addition to other pleiotropic effects that could explain their role in the pathogenesis of CAP. While most observational studies have shown that statins reduce risk of pneumonia in the general population, patients with diabetes, and recently in patients with myocardial infarction, no randomized controlled trial (RCT) to date has been conducted to assess the efficacy of statins to prevent development of CAP. Given the paucity of robust randomized evidence to assess statin use and the development of CAP, and considering conflicting results of the observational studies, we are not in favor of initiation of statins for either the prevention or treatment of CAP.

Discordance of physician clinical judgment vs. pneumonia severity index (PSI) score to admit patients with low risk community-acquired pneumonia: a prospective multicenter study

BACKGROUND

The relationship between clinical judgment and the pneumonia severity index (PSI) score in deciding the site of care for patients with community-acquired pneumonia (CAP) has not been well investigated. The objective of the study was to determine the clinical factors that influence decision-making to hospitalize low-risk patients (PSI ≤2) with CAP.

METHODS

An observational, prospective, multicenter study of consecutive CAP patients was performed at five hospitals in Spain. Patients admitted with CAP and a PSI ≤2 were identified. Admitting physicians completed a patient-specific survey to identify the clinical factors influencing the decision to admit a patient. The reason for admission was categorized into 1 of 6 categories. We also assessed whether the reason for admission was associated with poorer clinical outcomes [intensive care unit (ICU) admission, 30-day mortality or readmission].

RESULTS

One hundred and fifty-five hospitalized patients were enrolled. Two or more reasons for admission were seen in 94 patients (60.6%), including abnormal clinical test results (60%), signs of clinical deterioration (43.2%), comorbid conditions (28.4%), psychosocial factors (28.4%), suspected H1N1 pneumonia (20.6%), and recent visit to the emergency department (ED) in the past 2 weeks (7.7%). Signs of clinical deterioration and abnormal clinical test results were associated with poorer clinical outcomes (P<0.005).

CONCLUSIONS

Low-risk patients with CAP and a PSI ≤2 are admitted to the hospital for multiple reasons. Abnormal clinical test results and signs of clinical deterioration are two specific reasons for admission that are associated with poorer clinical outcomes in low risk CAP patients.

Admission levels of asymmetric and symmetric dimethylarginine predict long-term outcome in patients with community-acquired pneumonia

BACKGROUND

During infection, there is an activation of the L-arginine-nitric-oxide pathway, with a shift from nitric oxide synthesis to a degradation of L-arginine to its metabolites, asymmetric and symmetric dimethylarginine (ADMA and SDMA). However, the prognostic implications for short-term or long-term survival remains unclear. We investigated the association of L-arginine, ADMA, and SDMA with adverse clinical outcomes in a well-defined cohort of patients with community-acquired pneumonia (CAP).

METHODS

We measured L-arginine, ADMA, and SDMA in 268 CAP patients from a Swiss multicenter trial by mass spectrometry and used Cox regression models to investigate associations between blood marker levels and disease severity as well as mortality over a period of 6 years.

RESULTS

Six-year mortality was 44.8%. Admission levels of ADMA and SDMA (μmol/L) were correlated with CAP severity as assessed by the pneumonia severity index (r = 0.32, p < 0.001 and r = 0.56, p < 0.001 for ADMA and SDMA, respectively) and higher in 6-year non-survivors versus survivors (median 0.62 vs. 0.48; p < 0.001 and 1.01 vs. 0.85; p < 0.001 for ADMA and SDMA, respectively). Both ADMA and SDMA were significantly associated with long-term mortality (hazard ratios [HR] 4.44 [95% confidence intervals (CI) 1.84 to 10.74] and 2.81 [95% CI 1.45 to 5.48], respectively). The effects were no longer significant after multivariate adjustment for age and comorbidities. No association of L-arginine with severity and outcome was found.

CONCLUSIONS

Both ADMA and SDMA show a severity-dependent increase in patients with CAP and are strongly associated with mortality. This association is mainly explained by age and comorbidities.

TRIAL REGISTRATION

ISRCTN95122877 . Registered 31 July 2006.

Atypical Pneumonia: Updates on Legionella, Chlamydophila, and Mycoplasma Pneumonia

Community-acquired pneumonia (CAP) has multiple causes and is associated with illness that requires admission to the hospital and mortality. The causes of atypical CAP include Legionella species, Chlamydophila, and Mycoplasma. Atypical CAP remains a diagnostic challenge and, therefore, likely is undertreated. This article reviews the advancements in the evaluation and treatment of patients and discusses current conflicts and controversies of atypical CAP.

Lung Ultrasound Will Soon Replace Chest Radiography in the Diagnosis of Acute Community-Acquired Pneumonia

Acute community-acquired pneumonia should be diagnosed early to avoid most complications. The common diagnostic tools were represented by blood tests and chest X-ray with CT scan coming as a second-line exploration. The presence of air in the pulmonary parenchyma has long been thought of as not explorable by ultrasound. However, since the 1990s, several teams have described a semiology of ultrasonography of pulmonary diseases. Moreover, the safety of the technique and the development of mobile and ultra-portable devices have offered it as a first-line examination by a non-radiologist physician. The authors describe in this article ultrasonography as a way of learning the technique, and the main results observed in the literature. In conclusion, they propose it as the first-line examination instead of chest X-ray, and to reserve chest CT scan for complicated cases.

Prognostic value of on admission arterial PCO2 in hospitalized patients with community-acquired pneumonia

BACKGROUND

There is little data about the correlation between the outcome of community acquired pneumonia (CAP) and the hypercapnic type respiratory failure. In this study we prospectively investigated the prognostic significance of first arterial CO₂ tension in patients hospitalized with CAP.

METHODS

In this prospective study patients with CAP, admitted to a general hospital were included. PaCO₂ was measured for each subject in an arterial blood sample drawn in the first 2 hours and its correlations with three major outcomes were evaluated: intensive care unit (ICU) admission, duration of admission and mortality in 30 days.

RESULTS

A total of 114 patients (mean age: 60.9±18.3; male: 51.8%) diagnosed with CAP were included. Significant relationship was not found between PaCO₂ and mortality (P=0.544) or ICU admission (P=0.863). However advanced age, associated CHF, high BUN levels, high CURB-65 scores, associated pleural effusion in chest X-ray and being admitted to the ICU (P=0.012, 0.004, 0.003, <0.001, 0.045 and <0.001 respectively) were all significant prognostic factors of higher mortality risks. Prognostic factors for ICU admission were a history of malignancy (P=0.004), higher CURB-65 (P<0.001) scores and concomitant pleural effusion (P=0.028) in chest X-ray. Hypercapnic patients hospitalized for longer duration compared with normocapnic subjects. Furthermore, patients with lower pH (P=0.041) and pleural effusions (P=0.002) were hospitalized longer than the others.

CONCLUSIONS

There was less prominent prognostic value regarding on-admission PaCO₂ in comparison to other factors such as CURB-65. Considering the inconsistent results of surveys conducted on prognostic value of PaCO₂ for CAP outcomes, further investigations are required to reach a consensus on this matter.

A randomized, open, multicenter clinical study on the short course of intravenous infusion of 750 mg of levofloxacin and the sequential standard course of intravenous infusion/oral administration of 500 mg of levofloxacin for treatment of community-acquired pneumonia

BACKGROUND

To compare 5-day regimen of levofloxacin 750 mg IV daily with 7-14-day conventional regimen of levofloxacin 500 mg intravenous to oral (IV/PO) daily for treatment of community-acquired pneumonia (CAP) in Chinese population.

METHODS

This was a non-inferiority study to assess the difference of clinical efficacy at the end of treatment (EOT) between two regimens. Adult CAP patients with CURB-65 score 0-2 were enrolled from 17 hospitals in China from November 2012 to July 2014. The subjects were randomized into levofloxacin 750 or 500 mg group and the clinical data were collected. Sputum and blood specimens were sent for bacterial culture. The urinary antigen of Streptococcus pneumoniae (S. pneumoniae) was detected as well. At EOT, the clinical efficacy (primary endpoint), microbiological efficacy and safety were evaluated.

RESULTS

A total of 457 patients were enrolled. Intent-to-treat (ITT) for primary endpoint analysis and per-protocol set (PPS) populations were 448 and 427 patients respectively. The therapeutic durations were 4.86 and 10.35 days and the mean drug exposure was 3,641.4 and 5,169.6 mg in 750 and 500 mg groups respectively. The clinical efficacy rate was 91.40% (202/221) in 750 mg group and 94.27% (214/227) in 500 mg group (ITT, P=0.2449). The difference in clinical efficacy rate was -2.87 (95% CI: -7.64, 1.90) between the two groups. The non-inferiority hypothesis of two groups was tenable (Δ=10%). The bacterial eradication rate was 100.00% in both groups. The most common drug-related clinical adverse events were injection site and gastrointestinal reactions. The most common drug-related laboratory abnormalities were WBC decrease and ALT/AST elevation. No statistical difference was found between two groups (P>0.05).

CONCLUSIONS

The 5-day regimen of levofloxacin 750 mg daily is non-inferior to 7-14-day conventional regimen of 500 mg daily in clinical efficacy for treatment of mild to moderate Chinese CAP population. The short course regimen allows the reduction of antimicrobial drug exposure and is well tolerated.

Relevant Cytokines in the Management of Community-Acquired Pneumonia

Community-acquired pneumonia (CAP) is the leading cause of infectious death in the world. Immune dysregulation during acute lung infection plays a role in lung injury and the systemic inflammatory response. Cytokines seem to be major players in severe lung infection cases. Here, we present a review of published papers in the last 3 years regarding this topic. The cytokine response during pneumonia is different in bacterial vs viral infections; some of these cytokines correlate with clinical severity scales such as CURB65 or SOFA. Treatment focused in the cytokine environment is an interesting area that could impact the prognosis of CAP. Some of the agents that have been studied as co-adjuvant therapy are corticosteroids, macrolides, and linezolid, but anyone of those have shown a clear or proven efficacy or have been recommended as a part of the standard of care for CAP. More studies designed to define the role of immunomodulatory agents, such as co-adjuvant therapy in pneumonia, are needed.

[Respiratory infections in Emergencies]

Respiratory infections account for 63.8% of infections met. Of which a quarter are lower respiratory tract: acute bronchitis, exacerbation of COPD or bronchiectasis and pneumonia. Acute bronchitis usually of viral etiology and in immunocompetent patients without comorbidity treatment is symptomatic with analgesics and anti-inflammatories. The main cause of exacerbation of COPD is the respiratory infection. The indication of empirical antibiotic choice and it is based on clinical criteria, the severity of the underlying disease, the severity of the exacerbation and the presence of risk factors for infection with Pseudomonas aeruginosa. The community-acquired pneumonia (CAP) is the leading cause of death by infection. The use of prognostic severity scales (PSI or CURB-65) is recommended for deciding where treatment is started, the tests to be performed for the etiological diagnosis and the recommended empirical antibiotic therapy. Patients with Healthcare Associated Pneumonia (HCAP) and nosocomial pneumonia (NP) have a higher risk of infection by multiresistant microorganisms (MMR) and increased morbidity and mortality. It requires specific empirical treatment depending on the severity of disease and risk factors for infection MMR.

Serial quantification of procalcitonin (PCT) predicts clinical outcome and prognosis in patients with community-acquired pneumonia (CAP)

Procalcitonin (PCT), a calcitonin precursor, is commonly measured in the setting of community-acquired pneumonia (CAP). However, the clinical significance of serial PCT changes has not been established. We conducted a prospective observational study of 122 patients with CAP. Thirty-day mortality was the primary endpoint. Secondary endpoints included: (1) initial treatment failure, (2) 30-day mortality and/or initial treatment failure, and (3) intensive care unit (ICU) admission. In subgroup analysis, we classified patients into pneumococcal pneumonia and non-pneumococcal pneumonia groups. The baseline frequency of 30-day mortality was 10.7%. Increases in serum PCT levels from admission to Day 3 were observed with statistically higher frequency in patients with 30-day mortality (P = 0.002). For secondary endpoints, only the 30-day mortality and/or initial treatment failure group was statistically significant (P = 0.007). Subgroup analysis revealed statistically significant changes in the non-pneumococcal pneumonia group (N = 85) across several endpoints, including 30-day mortality (P = 0.001), initial treatment failure (P = 0.013), and 30-day mortality and/or initial treatment failure (P < 0.001). No significant changes in endpoint measurements were found in the pneumococcal pneumonia group (N = 28). Interestingly, serum PCT levels at the time of diagnosis were higher in patients with pneumococcal pneumonia than those with non-pneumococcal pneumonia (P = 0.006), and this positively correlated with disease severity scores for all patients (PCT vs. PSI: R = 0.380, P < 0.001; PCT vs.

A-DROP

R = 0.422, P < 0.001) and for non-pneumococcal pneumonia (PCT vs. PSI: R = 0.468, P < 0.001; PCT vs.

A-DROP

R = 0.448, P < 0.001), but not for pneumococcal pneumonia. In conclusion, serial quantification of PCT can predict clinical outcomes for patients with CAP.

Pneumococcal disease in the Arabian Gulf: recognizing the challenge and moving toward a solution

Pneumococcal disease has substantial incidence, morbidity and mortality in older adults. Decreased birth rates and longer lifespans indicate that the global population is aging, although rates of aging differ between countries [1]. In 2010, the proportion of the population aged >60 years in the general Arab Region was 7%, and this proportion is expected to rise to 19% by 2050 for the region as a whole [2]; the United Nations estimates for the individual countries of the Arabian Gulf by 2050 are 25.7%, 24.9%, 20.7%, 26.7% and 10.5% in the Kuwait, Bahrain, Qatar, United Arab Emirates (UAE) and Oman, respectively, which are comparable to the 26.9% predicted for the USA and lower than that predicted in European countries, in which the 2050 estimates are 32.7%, 34.0% and 38.1% for France, the UK and Germany, respectively [1]. Globally and in the Gulf Region, pneumococcal disease is an increasingly important public health burden in the elderly. The burden of pneumococcal disease can be reduced by effective vaccination programs, but the recommendations on pneumococcal vaccination in adults vary widely. The major barriers to vaccine implementation among healthcare professionals are an incomplete awareness of pneumococcal disease and the vaccination options in adults. The Gulf Advocate Group calls for healthcare providers in the countries of the Arabian Gulf (Kuwait, Bahrain, Qatar, United Arab Emirates and Oman) to support awareness and education programs about adult pneumococcal disease, particularly in high-risk groups such as those >65 years of age, those with type 2 diabetes mellitus, hematological malignancy, organ and bone marrow transplantation or chronic kidney or lung diseases and pilgrims undertaking the Hajj to improve pneumococcal disease surveillance and optimize and disseminate recommendations for adult vaccination. The Gulf Advocate Group recommends following the U.S. Centers for Disease Control and Prevention (CDC) guidelines for pneumococcal vaccination [3,4].