Pathogens In Community-acquired Pneumonia Research Articles

Results of Detecting SARS-CoV-2 and Other Pathogens of Community-Acquired Pneumonia by PCR in the Tyumen Region

The aim of this work was to identify the causative agent of community-acquired pneumonia and coinfection using PCR study of biomaterial from patients.Materials and methods. PCR testing of 268 samples from 258 patients was carried out to identify RNA/DNA of viral and bacterial pathogens of respiratory infections.Results and discussion. In 43.3 % of samples SARS-CoV-2 RNA was detected, in 4.5 % – RNA/DNA of acute respiratory viral infections pathogens, in one sample – DNA of Mycoplasma pneumoniae. Co-infection was detected only in patients of the anti-tuberculosis dispensary (SARS-CoV-2 and Mycobacterium tuberculosis). In the examined patients with pneumonia, SARS-CoV-2 RNA was significantly more often detected in biomaterial from the lower respiratory tract (52 %) than in respiratory smears (8.5 %). In the first week from the onset of the disease, 19.2 % of positive samples were found, in the second – 56.5 %.

Characteristics of Bacterial Microflora Isolated from Sputum of Patients with Pneumonia Registered in Khabarovsk City and Khabarovsk Territory in the Initial Period of COVID-19 Pandemic in May–June, 2020

Objective: to study the bacterial microflora in the sputum of patients with pneumonia caused by SARSCoV-2 or other pathogens.Materials and methods. The bacterial microflora of sputum of 173 patients with pneumonia admitted to hospitals in Khabarovsk and the Khabarovsk Territory in May – June 2020 was examined. Detection of RNA of the SARS-CoV-2 virus was carried out by PCR with the Vector-PCRRV-2019-nCoV-RG test system (manufactured by the State Scientific Center of VB “Vector”, Koltsovo). Determination of the DNA of mycoplasmosis agents and chlamydia was carried out with the test system “AmpliSens® Mycoplasma pneumoniae/Chlamydophila pneumonia” (manufactured by CRIE). Statistical data processing was performed using the Excel program. Results and discussion. Both groups of patients (Covid-19+ and Covid-19–) had high levels of bacterial flora isolation (81.4 and 74.7 %) including common pathogens for community-acquired pneumonia as well as notable detection frequency of Candida spp. and microbial associations. The group of Covid-19+ patients demonstrated a wider range of detected pathogens, was positive for poly-resistant gram-negative Enterobacteriaceae, non-fermenting gram-negative poly-resistant bacteria, with more expressed manifestation of microbial associations. In the group of Covid-19– participants drug-resistant microflora was presented only by MRSA and MRSE staphylococci.

Enhanced Detection of Community-Acquired Pneumonia Pathogens With the BioFire® Pneumonia FilmArray® Panel

BackgroundAlthough most observational studies identify viral or bacterial pathogens in 50% or less of patients hospitalized with community-acquired pneumonia (CAP), we previously demonstrated that a multi-test bundle (MTB) detected a potential pathogen in 73% of patients. This study compares detection rates for potential pathogens with the MTB versus the Biofire® Pneumonia FilmArray® panel (BPFA) multiplex PCR platform and presents an approach for integrating BPFA results as a foundation for subsequent antibiotic stewardship (AS) activities.MethodsBetween January 2017 to March 2018, all patients admitted for CAP were enrolled. Patients were considered evaluable if all elements of the MTB and the BPFA were completed, and they met other a priori inclusion criteria. The primary endpoint was the percentage of potential pathogens detected using the MTB (8 viral and 6 bacterial targets) versus the BPFA (8 viral and 18 bacterial targets). Blood and sputum cultures were performed on all patients. Two or more procalcitonin (PCT) levels assisted clinical assessments as to whether detected bacteria were invading or colonizing.ResultsOf 585 enrolled patients, 274 were evaluable. A potential viral pathogen was detected in 40.5% with MTB versus 60.9% of patients with BPFA with an odds ratio (95% CI) of 9.00 (4.12 to 23.30) p<0.01. A potential bacterial pathogen was identified in 66.4% with the MTB vs 75.5% with the BPFA odds ratio (95% CI) of 2.09 (1.24 to 3.59), p 0.003). Low PCT levels helped identify detected bacteria as colonizers.

Community-Acquired Bacterial Pneumonia-Changing Epidemiology, Resistance Patterns, and Newer Antibiotics: Spotlight on Delafloxacin.

Community-acquired pneumonia (CAP) is a major cause of morbidity and mortality both in the USA and globally. As the burden of CAP continues to increase due to several factors, the advances in its diagnosis, prevention, and treatment have taken on even greater interest and importance. The majority of CAP patients are treated empirically, and selection of appropriate antibiotic treatment is increasingly difficult because the epidemiology of CAP is changing, in part due to antimicrobial resistance, and the causative CAP pathogens differ between countries and regions. There is also an increasing prevalence of chronic co-morbid diseases among CAP patients. Treatment of CAP has become challenging because of these factors along with the varying safety profiles and efficacy of well-established antibiotics, as well as limited new therapeutic options. Recently, however, new antibiotics have been approved, which will expand the treatment options for CAP, particularly in those patients with underlying complications. Recently approved delafloxacin, an anionic fluoroquinolone, has a unique structure and distinct chemical characteristics; it demonstrated non-inferiority to moxifloxacin in a phase III clinical trial, but was shown to be superior to moxifloxacin at early clinical response in CAP patients who also have chronic obstructive pulmonary disease (COPD) or asthma as a co-morbidity, and in CAP patients who may have severe illness. Delafloxacin could offer an additional therapy against resistant isolates and among these difficult-to-treat patients. This review summarizes the development, latest research, and safety profile of the new antibiotic delafloxacin, and its potential future role in the treatment of CAP.

An analysis of 20 clinical cases of refractory mycoplasma pneumonia in children.

Refractory mycoplasma pneumonia (RMPP) is one of the important pathogens of community-acquired pneumonia (CAP) in children. Its treatment is difficult. The aims of this study were to analyze the clinical manifestations, diagnosis, and treatment of 20 cases of RMPP in children in order to provide a reference for the diagnosis and treatment of RMPP. The clinical data of 20 patients with RMPP admitted to the Pediatrics Department of the First Affiliated Hospital of Guangzhou Medical University in the recent three years were retrospectively analyzed. The clinical data of 36 patients with common mycoplasma pneumonia in the same period were compared. The clinical manifestations, laboratory examinations, and imaging characteristics of RMPP were discussed. Intrapulmonary and extrapulmonary complications and treatment were also analyzed in order to provide assistance in the diagnosis and treatment of RMPP. There were significant differences between the refractory group and the general group in terms of heat duration, hospitalization time, hypoxemia, lung rales, CRP, ESR, PCT, LDH, ALT, PLT, WBC, D dimer and other laboratory examinations, intrapulmonary and extrapulmonary complications, and treatment (all P<0.05). There was no significant difference in the age, sex, and wheezing between the two groups (P>0.05). Long duration of fever, tachycardia, and lung rale protrusion may be the clinical characteristics of RMPP. Unilateral pulmonary shadow and atelectasis should be paid more attention, which may be a high-risk factor for the development of RMPP. The inflammation index of RMPP cases increased and there were many complications inside and outside the patients' lungs. It was necessary to give enough macrolides to fight the infection by using Glucocorticoid and Intravenous immunoglobulin reasonably while liver, heart, and fiberoptic bronchoscopy was completed to improve the effectiveness of the diagnosis and treatment.

Investigation of the clinical significance of detecting PTX3 for community-acquired pneumonia.

To evaluate the value of PTX3 in the diagnosis of community-acquired pneumonia (CAP). We included 170 inpatients diagnosed with CAP from January 2016 to December 2018. The patients were divided into the severe pneumonia group and the mild pneumonia group according to their condition. According to the results of pathogen detection, they were divided into the bacterial infection group, the virus infection group, the mixed infection group, and the other pathogen infection group. Clinical data including C-reactive protein (CRP), procalcitonin (PCT), white blood cell count (WBC), and neutrophil-lymphocyte ratio (NLR) were collected. Blood was collected within 24 hours, 3 days, and 7 days after admission, and the serum PTX3 level was dynamically monitored. The correlation between different groups was compared, and expression differences and dynamic changes of PTX3 were analyzed. PTX3, PCT, and CRP in the CAP group were higher than those in the healthy control group, and the difference was statistically significant (p<0.05). Compared with the mild group, the increase of PTX3, PCT, and CRP was also different in the severe group (p<0.05). The area under the ROC curve of PTX3 was 0.726 (sensitivity 76.08%, specificity 76.92%) when the threshold value was 32.26 ng/ml. Dynamic monitoring of PTX3 showed that the PTX3 level in severe CAP patients was significantly higher than that in mild patients (p<0.05), and the PTX3 level in both groups gradually decreased with treatment time, but the level in severe CAP patients remained at a high level on the 7th day. The main pathogens in CAP were bacteria (77 cases, 45.7%), and there was no significant difference in the PTX3 level among the patients infected with different pathogenic bacteria (p=0.311). The serum PTX3 level, especially the dynamic monitoring results, can be used as a biomarker to reflect community acquired pneumonia, which can provide effective auxiliary diagnosis and efficacy in monitoring for clinical practice.

Factors associated with pneumococcal vaccine uptake in elderly subjects referred to the respiratory department.

ABSTRACT Streptococcus pneumoniae is the most common pathogen for community-acquired pneumonia and is also common in nursing and healthcare-associated pneumonia. Pneumococcal vaccine shows clinical benefit and 23-valent pneumococcal polysaccharide vaccine (PPSV23) has been introduced in a routine immunization program in Japan. However, uptake of PPSV23 remains low, at 40%. One opportunity for capturing unvaccinated subjects is hospital referrals. Identifying factors associated with pneumococcal vaccination among referred subjects is thus important so that pulmonologists can maximize the capture of unvaccinated subjects. We retrospectively reviewed the records of subjects with a first referral to the Department of Respiratory Medicine at Hiratsuka City Hospital from September 2017 to March 2018. Subjects who were ≥65 years old and lived in Hiratsuka were included in this study. We compared the backgrounds of subjects and investigated factors associated with pneumococcal vaccination. A total of 142 individuals were included in this study and the pneumococcal vaccination rate was 44.4% (95% confidence interval (CI), 36.0–52.9%). Of these, 127 subjects regularly visited clinics and/or hospitals for any diseases and their pneumococcal vaccine rate was 44.1% (95%CI, 35.3–53.2%). In multivariate analysis, chronic respiratory diseases (odds ratio 5.7; 95%CI, 2.2–14.9, P<0.001) and receipt of PPSV23 notification (odds ratio 8.5; 95%CI, 2.5–29.0, P<0.001) were positively associated with pneumococcal vaccination. In conclusion, chronic respiratory diseases and receipt of PPSV23 notification were positively associated with pneumococcal vaccination. However, pneumococcal vaccination rates remain relatively low, even in subjects regularly visiting clinics and/or hospitals.

Where is Chlamydophila pneumoniae pneumonia?

Molecular diagnostic methods have recently gained widespread use, and consequently, the importance of viral pathogens in community-acquired pneumonia (CAP) has undergone re-evaluation. Under these circumstances, the role of Chlamydophila pneumoniae as a pathogen that causes CAP also needs to be reviewed. We reviewed articles that contained data on the frequency of identification of C. pneumoniae pneumonia as a causative pathogen for CAP. The articles were identified by performing a search in PubMed with the keywords "community-acquired pneumonia" and "pathogen". Sixty-three articles were identified. The reviewed articles demonstrated that the rates of identification of C. pneumoniae as the causative pathogen for CAP were significantly lower in assessments based on polymerase chain reaction (PCR) methods than in those based on serological methods. In some studies, it was possible to compare both serological and PCR methods directly using the same set of samples. The use of PCR methods, including multiplex PCR assays, has revealed that C. pneumoniae may play a limited role as a pathogen for CAP.

Characteristics and etiology of hospitalized pediatric community-acquired pneumonia in Taiwan

Background/purposeThe purpose of this study was to determine the pathogens and to estimate the incidence of pediatric community-acquired pneumonia (CAP) in Taiwan.MethodsThis prospective study was conducted at eight medical centers from November 2010 to September 2013. Children aged 6 weeks to 18 years who met the radiologic criteria for pneumonia were enrolled. To detect classical and atypical bacteria and viruses, blood and pleural fluids were cultured, and respiratory specimens were examined by multiple conventional and molecular methods.ResultsAt least one potential pathogen was identified in 705 (68.3%) cases of 1032 children enrolled, including bacteria in 420 (40.7%) cases, virus in 180 (17.4%) cases, and mixed viral-bacterial infection in 105 (10.2%) cases. Streptococcus pneumoniae (31.6%) was the most common pathogen, followed by Mycoplasma pneumoniae (22.6%). Adenovirus (5.9%) was the most common virus. RSV was significantly associated with children aged under 2 years, S. pneumoniae in children aged between 2 and 5 years, and M. pneumoniae in children aged >5 years. The annual incidence rate of hospitalization for CAP was highest in children aged 2–5 years (229.7 per 100,000). From 2011 to 2012, significant reduction in hospitalization rates pertained in children under 5 years of age, in pneumonia caused by pneumococcus, adenovirus or co-infections and complicated pneumonia.ConclusionCAP related pathogens have changed after increased conjugated pneumococcal vaccination rates. This study described the latest incidences and trends of CAP pathogens, which are crucial for prompt delivery of appropriate therapy.

Other Respiratory Viruses as a Cause of Community-Acquired Pneumonia.

Community-acquired pneumonia (CAP) is a major cause of morbidity and mortality worldwide. There is growing appreciation of the burden of noninfluenza viral pathogens in CAP. Due to multiple factors including pneumococcal vaccination programs, declining rates of cigarette smoking, an aging population, and increasingly sensitive diagnostic tests, respiratory viruses are now the most common pathogens detected in CAP, outpacing Streptococcus pneumoniae. Noninfluenza respiratory pathogens are widely accepted as causal pathogens in CAP including in immunocompetent patients. This review provides an overview of five noninfluenza respiratory viral pathogens commonly implicated in CAP pathogenesis: rhinovirus, human metapneumovirus, respiratory syncytial virus, human parainfluenza virus, and human adenoviruses. Nucleic acid amplification testing platforms and their impact on antimicrobial stewardship efforts are also considered.

Emerging Resistance of Gram Negative Pathogens in Community-Acquired Pneumonia.

In recent decades, there has been a growing interest about the role of gram negative bacteria in community-acquired pneumonia (CAP), especially Pseudomonas aeruginosa, Enterobacteriaceae, and Acinetobacter baumannii. The prevalence of these pathogens differs largely according to the local ecology and the geographical location. Identifying gram negative bacteria, and in particular resistant gram negative bacteria, is of paramount importance in patients with CAP because these pathogens are associated with higher clinical severity and unfavorable outcomes. The use of individualized risk factors to predict each pathogen is a helpful strategy that needs to be locally validated. However, it should be taken into account that most of the risk factors identified in the literature are heterogeneously defined or lack consistency. New diagnostic techniques, such as molecular testing, are promising methods for early detection of these gram negative pathogens. The increasing mechanisms of resistance to antibiotics of these pathogens have limited our therapeutic approach. This narrative review focuses on the epidemiology, risk factors, diagnosis, and therapeutic options for the most relevant gram negative bacteria that cause CAP.

Human adenovirus Coinfection aggravates the severity of Mycoplasma pneumoniae pneumonia in children

BackgroundMycoplasma pneumoniae (M. pneumoniae) is an important pathogen of community-acquired pneumonia (CAP) in children. The coinfection rate of M. pneumoniae pneumonia (MPP) can reach 52% in some areas, but the effects of coinfection with different pathogens have not been clearly recognized.MethodsThe cases of MPP hospitalized in Beijing Children’s Hospital from 1/1/2014 to 12/31/2016 were screened. MPP patients coinfected with Human adenovirus (HAdV) were categorized into the research group. Patients with single M. pneumoniae infection were categorized into the control group, matching the research group by age and admission time with a ratio of 1:3. Clinical manifestations, laboratory examinations, and disease severity were compared between these two groups.ResultsA total of 2540 hospitalized MPP cases were screened in Beijing Children’s Hospital, among which thirty cases were enrolled in the research group and ninety cases were enrolled in the control group. The results indicated that patients in the research group had longer hospital stays, longer fever durations and a higher rate of dyspnea, as well as a larger proportion applications of oxygen therapy and noninvasive continuous positive airway pressure (NCPAP). No obvious differences were found in lab examinations within the two groups. Regarding disease severity, the proportions of extremely severe pneumonia and severe disease defined by the clinical score system were higher in the research group than in the control group.ConclusionCompared with single M. pneumoniae infection, MPP coinfected with HAdV in children was relatively more serious.

Use of a rapid recombinase-aided amplification assay for Mycoplasma pneumoniae detection

BackgroundMycoplasma pneumoniae is one of the most common causative pathogens of community-acquired pneumonia (CAP), accounting for as many as 30–50% of CAP during peak years. An early and rapid diagnostic method is key for guiding clinicians in their choice of antibiotics.MethodsThe recombinase-aided amplification (RAA) assay is a recently developed, rapid detection method that has been used for the detection of several pathogens. The assays were performed in a one-step single tube reaction at 39° Celsius within 15–30 min. In this study, we established an RAA assay for M. pneumoniae using clinical specimens for validation and commercial real-time PCR as the reference method.ResultsThe analytical sensitivity of the RAA assay was 2.23 copies per reaction, and no cross-reactions with any of the other 15 related respiratory bacterial pathogens were observed. Compared with the commercial real-time PCR assay used when testing 311 respiratory specimens, the RAA assay obtained 100% sensitivity and 100% specificity with a kappa value of 1.ConclusionsThese results demonstrate that the proposed RAA assay will be of benefit as a faster, sensitive, and specific alternative tool for the detection of M. pneumoniae.

Antimicrobial resistance in bacteria associated with childhood pneumonia in Malawi

Community acquired pneumonia (CAP) is a disease caused by an infection (by bacteria, viruses or fungi) that in cases of chronic infection lead to high mortality rates particularly in children. Pneumonia is the leading cause of death in children under the age of five worldwide with over 2 million deaths reported in 2016 by the World Health Organisation. Developing countries in sub Saharan Africa such as Malawi see some of the highest rates of the disease. CAP infections are responsible for 20% of deaths of new-borns in Malawi. Antibiotic resistance in disease causing organisms is of growing concern in countries like Malawi. We obtained bacterial isolates from blood samples taken from Malawian children, aged 18 -60 months, diagnosed with CAP. Streptococcus pneumonia is the primary pathogen in CAP but associated ESKAPE pathogens like Pseudomonas and Staphylococci spp. and Escherichia coli are of growing importance. These were the most common bacteria purified, isolated and characterised from these samples resulting in a unique culture collection. These pathogens have been screened for antimicrobial resistance with a variety of antibiotics to generate a resistance profile based on the minimal inhibitory concentrations of selected isolates using antibiotic susceptibility disks and by broth dilution method. Initial assessment shows current front-line therapies used by the Malawian ministry of health are ineffective in treating CAP. Our research aims to fully characterise these strains at the genetic level to better understand the mechanisms behind how antibiotic resistance develops to aid in combating this growing issue in countries like Malawi.

Community-acquired pneumonia. Diagnosis, treatment approaches

The article presents current data on the prevalence and etiology of community-acquired pneumonia, shows the contribution of each of the possible pathogens to the structure of the disease. The diagnostic criteria for pneumonia are given. The main algorithms for assessing the severity of pneumonia and the prognosis of the disease using different scales: CURB-65 / CRB-65, PORT (PSI), are described. The purpose of the test is to determine the place of treatment: outpatient or in the in-patient department, in the general department or in the intensive care unit. The criteria for IDSA / ATS (American Thoracic Society / American Society of Infectious Diseases), as well as the SMART-COP / SMRCO scale to determine the need for hospitalized patients in the intensive care unit, are reviewed. The Aliberti and PES scales are given, assessing the risk of the presence of resistant pathogens in community-acquired pneumonia. Modern recommendations on the empirical choice of antibacterial drugs depending on individual patient factors are presented: anamnestic indications for treatment with antimicrobials during the preceding three months, hospitalization within six months before the onset of pneumonia, the presence of comorbidities, the severity of the disease, the risk of resistant pathogens. The average therapeutic doses of antibacterial drugs for the treatment of community-acquired pneumonia in patients with normal renal function are indicated. The questions of the optimal duration of treatment of pneumonia depending on the etiology are considered, the criteria of sufficiency of antibacterial therapy are presented. The reasons for the possible ineffectiveness of the empirical antibiotic therapy of community-acquired pneumonia are described. The importance of identifying a particular form of community-acquired pneumonia – severe community-acquired pneumonia is emphasized. Described drugs for the treatment of severe community-acquired pneumonia. The issues of prevention of pneumonia were discussed, its importance in the strategy of reducing mortality according to the World Health Organization was emphasized.

Etiology of community-acquired pneumonia in patients with chronic heart failure

Chronic heart failure (CHF) is one of the most common comorbidities in elderly patients with community-acquired pneumonia (CAP).The aim of this study was to investigate etiology of CAP in patients with concomitant CHF.Methods. This prospective observational study involved adult hospitalized patients with CAP and concomitant CHF. CAP was confirmed by chest X-ray. Sputum samples or oropharyngeal swabs, blood and urine samples were collected in all eligible patients before starting the therapy with systemic antibiotics. Sputum was cultured for «typical» bacterial pathogens, such as Streptococcus pneumoniae, Staphylococcus aureus, Enterobacterales, etc., in accordance with standard methods and procedures. Mycoplasma pneumoniae, Chlamydophila pneumoniae and respiratory viruses in sputum or oropharyngeal swabs were identified using the real-time polymerase chain reaction (PCR). Urine samples were used to determine serogroup 1 Legionella pneumophila and S. pneumoniae soluble antigens using bedside immunochromatography.Results. Fifty patients were enrolled in the study. The mean age was 72.2 ± 9.5 years, 27 (54%) were females. The etiology of CAP was identified in 23 cases (46%). S. pneumoniae was the most common pathogen (16/23; 69.7%) followed by respiratory viruses (3/23; 13.1%), such as type 3 parainfluenza virus, coronavirus, human metapneumovirus; Haemophilus influenzae (1/23; 4.3%), S. aureus (1/23; 4.3%), and Klebsiella pneumoniae (1/23; 4.3%). S. pneumoniae and parainfluenza virus co-infection was diagnosed in one of 23 patients (4.3%).Conclusion. S. pneumoniae and respiratory viruses were predominant causative pathogens of CAP in hospitalized adults with concomitant CHF. Therefore, bedside tests for urine pneumococcal antigens should be used more widely considering difficult sputum expectoration in elderly. Atypical bacterial pathogens (M. pneumoniae, C. pneumoniae, L. pneumophila) were not identified in this study, so the routine PCR-test and urine tests for L. pneumophila antigens are thought to be not useful.

Yap/Taz regulate alveolar regeneration and resolution of lung inflammation.

Alveolar epithelium plays a pivotal role in protecting the lungs from inhaled infectious agents. Therefore, the regenerative capacity of the alveolar epithelium is critical for recovery from these insults in order to rebuild the epithelial barrier and restore pulmonary functions. Here, we show that sublethal infection of mice with Streptococcus pneumoniae, the most common pathogen of community-acquired pneumonia, led to exclusive damage in lung alveoli, followed by alveolar epithelial regeneration and resolution of lung inflammation. We show that surfactant protein C-expressing (SPC-expressing) alveolar epithelial type II cells (AECIIs) underwent proliferation and differentiation after infection, which contributed to the newly formed alveolar epithelium. This increase in AECII activities was correlated with increased nuclear expression of Yap and Taz, the mediators of the Hippo pathway. Mice that lacked Yap/Taz in AECIIs exhibited prolonged inflammatory responses in the lung and were delayed in alveolar epithelial regeneration during bacterial pneumonia. This impaired alveolar epithelial regeneration was paralleled by a failure to upregulate IκBa, the molecule that terminates NF-κB-mediated inflammatory responses. These results demonstrate that signals governing resolution of lung inflammation were altered in Yap/Taz mutant mice, which prevented the development of a proper regenerative niche, delaying repair and regeneration of alveolar epithelium during bacterial pneumonia.

PES Pathogens in Severe Community-Acquired Pneumonia.

Worldwide, there is growing concern about the burden of pneumonia. Severe community-acquired pneumonia (CAP) is frequently complicated by pulmonary and extra-pulmonary complications, including sepsis, septic shock, acute respiratory distress syndrome, and acute cardiac events, resulting in significantly increased intensive care admission rates and mortality rates. Streptococcus pneumoniae (Pneumococcus) remains the most common causative pathogen in CAP. However, several bacteria and respiratory viruses are responsible, and approximately 6% of cases are due to the so-called PES (Pseudomonas aeruginosa, extended-spectrum β-lactamase Enterobacteriaceae, and methicillin-resistant Staphylococcus aureus) pathogens. Of these, P. aeruginosa and methicillin-resistant Staphylococcus aureus are the most frequently reported and require different antibiotic therapy to that for typical CAP. It is therefore important to recognize the risk factors for these pathogens to improve the outcomes in patients with CAP.

A case report of community-acquired Pseudomonas aeruginosa pneumonia complicated with MODS in a previously healthy patient and related literature review

BackgroundPseudomonas aeruginosa is an unusual pathogen in community-acquired pneumonia, especially in previously healthy adults, but often indicates poor prognosis.Case presentationWe report a previously healthy patient who developed severe community-acquired pneumonia (CAP) caused by P. aeruginosa. He deteriorated to septic shock and multiple organ dysfunction syndrome (MODS) quickly, complicated by secondary hematogenous central nervous system (CNS) infection. After 1 month of organ support and antipseudomonal therapy, he had significant symptomatic improvement and was discharged from hospital. During treatment, the pathogen developed resistance to carbapenems quickly and the antibiotic regimen was adjusted accordingly.ConclusionsAccording to our case and related literature review, we conclude that more attention should be paid to community-acquired Pseudomonas aeruginosa pneumonia, because of its rapid progression and poor prognosis.

Multicenter study of human adenovirus infection in pediatric community-acquired pneumonia in China

Objective: To investigate the predominant genotypes and epidemiological characteristics of human adenovirus (HAdV) in pediatric community-acquired pneumonia (CAP) in China. Methods: This was a repeated cross sectional study. Between November 2014 and November 2016, nasopharyngeal aspirates (NPAs) or throat swabs from each hospitalized pediatric patients diagnosed as CAP in 12 hospitals in Northern and Southern China were collected. Respiratory specimens were screened for 18 respiratory viruses including HAdV by using Luminex xTAG RVP Fast V2 multiplex Assay. Typing of HAdV and analysis for the epidemiological characteristic of HAdV were performed. Results: (1) A total of 2 723 hospitalized pediatric patients with CAP were enrolled in this study and 156 (5.7%, 156/2 723) respiratory specimens were positive for HAdV, and 74 (6.6%, 74/1 128) and 82 (5.1%, 82/1 595) were in Northern and Southern China, respectively. There was no significant difference in the positive detection rate between the Northern and Southern China. (2) In Northern China, the HAdV positive rate of children at the age of <6 months, 6 months-<1 years, 1-<3 years, 3-<5 years and ≥5 years was 5.9%(6/101), 6.7%(7/104), 10.3%(34/331), 4.1%(11/266) and 4.9%(16/326), respectively, and the incidence of HAdV infection peaked in children aged 1-3 years (χ(2)=11.511, P=0.021). While in Southern China the HAdV positive rate of children at the age of <6 months, 6 months-<1 years, 1-<3 years, 3-<5 years and ≥5 years was 2.2% (7/312), 4.6% (12/259), 6.3% (31/494), 7.3% (18/245) and 4.9%(14/285), respectively. There was no significant difference in the positive detection rate among age groups. (3) In 2015, the highest detection rate of HAdV in northern China was 12.5% (25/200) in winter, and in Southern China was 6.7% (35/525) in spring and 5.3% (19/357) in summer. (4) In 108 cases of HAdV positive specimens typing was done and 80 in cases classification was successfully performed.Totally 7 genotypes of HAdV, including HAdV-3 (n=32), HAdV-7 (n=9), HAdV-1 (n=12), HAdV-2 (n=15), HAdV-5 (n=10), HAdV-6 (n=1) and HAdV-4 (n=1), were detected. The predominant HAdV genotypes were HAdV-3 (30.8%, 8/26) and HAdV-7 (26.9%, 7/26) in Northern China, while HAdV-3 (44.4%, 24/54) and HAdV-2 (22.2%, 12/54) were the most prevalent genotypes in Southern China. Conclusions: HAdV is an important viral pathogen in pediatric CAP. The predominant HAdV genotypes and peak seasons of HAdV infections were different between Northern and Southern China. The predominant HAdV genotypes were HAdV-3 and HAdV-7 in Northern China, while HAdV-3 and HAdV-2 in Southern China. The peak season of HAdV infections was winter in Northern China. However, HAdV infections are more common in spring and summer in Southern China.